Stable structural color patterns displayed on transparent insect wings.
Shevtsova, Ekaterina; Hansson, Christer; Janzen, Daniel H; Kjærandsen, Jostein
2011-01-11
Color patterns play central roles in the behavior of insects, and are important traits for taxonomic studies. Here we report striking and stable structural color patterns--wing interference patterns (WIPs)--in the transparent wings of small Hymenoptera and Diptera, patterns that have been largely overlooked by biologists. These extremely thin wings reflect vivid color patterns caused by thin film interference. The visibility of these patterns is affected by the way the insects display their wings against various backgrounds with different light properties. The specific color sequence displayed lacks pure red and matches the color vision of most insects, strongly suggesting that the biological significance of WIPs lies in visual signaling. Taxon-specific color patterns are formed by uneven membrane thickness, pigmentation, venation, and hair placement. The optically refracted pattern is also stabilized by microstructures of the wing such as membrane corrugations and spherical cell structures that reinforce the pattern and make it essentially noniridescent over a large range of light incidences. WIPs can be applied to map the micromorphology of wings through direct observation and are useful in several fields of biology. We demonstrate their usefulness as identification patterns to solve cases of cryptic species complexes in tiny parasitic wasps, and indicate their potentials for research on the genetic control of wing development through direct links between the transregulatory wing landscape and interference patterns we observe in Drosophila model species. Some species display sexually dimorphic WIPs, suggesting sexual selection as one of the driving forces for their evolution.
Stable structural color patterns displayed on transparent insect wings
Shevtsova, Ekaterina; Hansson, Christer; Janzen, Daniel H.; Kjærandsen, Jostein
2011-01-01
Color patterns play central roles in the behavior of insects, and are important traits for taxonomic studies. Here we report striking and stable structural color patterns—wing interference patterns (WIPs)—in the transparent wings of small Hymenoptera and Diptera, patterns that have been largely overlooked by biologists. These extremely thin wings reflect vivid color patterns caused by thin film interference. The visibility of these patterns is affected by the way the insects display their wings against various backgrounds with different light properties. The specific color sequence displayed lacks pure red and matches the color vision of most insects, strongly suggesting that the biological significance of WIPs lies in visual signaling. Taxon-specific color patterns are formed by uneven membrane thickness, pigmentation, venation, and hair placement. The optically refracted pattern is also stabilized by microstructures of the wing such as membrane corrugations and spherical cell structures that reinforce the pattern and make it essentially noniridescent over a large range of light incidences. WIPs can be applied to map the micromorphology of wings through direct observation and are useful in several fields of biology. We demonstrate their usefulness as identification patterns to solve cases of cryptic species complexes in tiny parasitic wasps, and indicate their potentials for research on the genetic control of wing development through direct links between the transregulatory wing landscape and interference patterns we observe in Drosophila model species. Some species display sexually dimorphic WIPs, suggesting sexual selection as one of the driving forces for their evolution. PMID:21199954
Genetic Basis of Melanin Pigmentation in Butterfly Wings
Zhang, Linlin; Martin, Arnaud; Perry, Michael W.; van der Burg, Karin R. L.; Matsuoka, Yuji; Monteiro, Antónia; Reed, Robert D.
2017-01-01
Despite the variety, prominence, and adaptive significance of butterfly wing patterns, surprisingly little is known about the genetic basis of wing color diversity. Even though there is intense interest in wing pattern evolution and development, the technical challenge of genetically manipulating butterflies has slowed efforts to functionally characterize color pattern development genes. To identify candidate wing pigmentation genes, we used RNA sequencing to characterize transcription across multiple stages of butterfly wing development, and between different color pattern elements, in the painted lady butterfly Vanessa cardui. This allowed us to pinpoint genes specifically associated with red and black pigment patterns. To test the functions of a subset of genes associated with presumptive melanin pigmentation, we used clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing in four different butterfly genera. pale, Ddc, and yellow knockouts displayed reduction of melanin pigmentation, consistent with previous findings in other insects. Interestingly, however, yellow-d, ebony, and black knockouts revealed that these genes have localized effects on tuning the color of red, brown, and ochre pattern elements. These results point to previously undescribed mechanisms for modulating the color of specific wing pattern elements in butterflies, and provide an expanded portrait of the insect melanin pathway. PMID:28193726
Distal-less induces elemental color patterns in Junonia butterfly wings.
Dhungel, Bidur; Ohno, Yoshikazu; Matayoshi, Rie; Iwasaki, Mayo; Taira, Wataru; Adhikari, Kiran; Gurung, Raj; Otaki, Joji M
2016-01-01
The border ocellus, or eyespot, is a conspicuous color pattern element in butterfly wings. For two decades, it has been hypothesized that transcription factors such as Distal-less (Dll) are responsible for eyespot pattern development in butterfly wings, based on their expression in the prospective eyespots. In particular, it has been suggested that Dll is a determinant for eyespot size. However, functional evidence for this hypothesis has remained incomplete, due to technical difficulties. Here, we show that ectopically expressed Dll induces ectopic elemental color patterns in the adult wings of the blue pansy butterfly, Junonia orithya (Lepidoptera, Nymphalidae). Using baculovirus-mediated gene transfer, we misexpressed Dll protein fused with green fluorescent protein (GFP) in pupal wings, resulting in ectopic color patterns, but not the formation of intact eyespots. Induced changes included clusters of black and orange scales (a basic feature of eyespot patterns), black and gray scales, and inhibition of cover scale development. In contrast, ectopic expression of GFP alone did not induce any color pattern changes using the same baculovirus-mediated gene transfer system. These results suggest that Dll plays an instructive role in the development of color pattern elements in butterfly wings, although Dll alone may not be sufficient to induce a complete eyespot. This study thus experimentally supports the hypothesis of Dll function in eyespot development.
Genetic Basis of Melanin Pigmentation in Butterfly Wings.
Zhang, Linlin; Martin, Arnaud; Perry, Michael W; van der Burg, Karin R L; Matsuoka, Yuji; Monteiro, Antónia; Reed, Robert D
2017-04-01
Despite the variety, prominence, and adaptive significance of butterfly wing patterns, surprisingly little is known about the genetic basis of wing color diversity. Even though there is intense interest in wing pattern evolution and development, the technical challenge of genetically manipulating butterflies has slowed efforts to functionally characterize color pattern development genes. To identify candidate wing pigmentation genes, we used RNA sequencing to characterize transcription across multiple stages of butterfly wing development, and between different color pattern elements, in the painted lady butterfly Vanessa cardui This allowed us to pinpoint genes specifically associated with red and black pigment patterns. To test the functions of a subset of genes associated with presumptive melanin pigmentation, we used clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing in four different butterfly genera. pale , Ddc , and yellow knockouts displayed reduction of melanin pigmentation, consistent with previous findings in other insects. Interestingly, however, yellow-d , ebony , and black knockouts revealed that these genes have localized effects on tuning the color of red, brown, and ochre pattern elements. These results point to previously undescribed mechanisms for modulating the color of specific wing pattern elements in butterflies, and provide an expanded portrait of the insect melanin pathway. Copyright © 2017 by the Genetics Society of America.
2014-01-01
Background The colorful wing patterns of butterflies, a prime example of biodiversity, can change dramatically within closely related species. Wing pattern diversity is specifically present among papilionid butterflies. Whether a correlation between color and the evolution of these butterflies exists so far remained unsolved. Results We here investigate the Cattlehearts, Parides, a small Neotropical genus of papilionid butterflies with 36 members, the wings of which are marked by distinctly colored patches. By applying various physical techniques, we investigate the coloration toolkit of the wing scales. The wing scales contain two different, wavelength-selective absorbing pigments, causing pigmentary colorations. Scale ridges with multilayered lamellae, lumen multilayers or gyroid photonic crystals in the scale lumen create structural colors that are variously combined with these pigmentary colors. Conclusions The pigmentary and structural traits strongly correlate with the taxonomical distribution of Parides species. The experimental findings add crucial insight into the evolution of butterfly wing scales and show the importance of morphological parameter mapping for butterfly phylogenetics. PMID:25064167
Sánchez Herrera, Melissa; Kuhn, William R; Lorenzo-Carballa, Maria Olalla; Harding, Kathleen M; Ankrom, Nikole; Sherratt, Thomas N; Hoffmann, Joachim; Van Gossum, Hans; Ware, Jessica L; Cordero-Rivera, Adolfo; Beatty, Christopher D
2015-01-01
The study of color polymorphisms (CP) has provided profound insights into the maintenance of genetic variation in natural populations. We here offer the first evidence for an elaborate wing polymorphism in the Neotropical damselfly genus Polythore, which consists of 21 described species, distributed along the eastern slopes of the Andes in South America. These damselflies display highly complex wing colors and patterning, incorporating black, white, yellow, and orange in multiple wing bands. Wing colors, along with some components of the male genitalia, have been the primary characters used in species description; few other morphological traits vary within the group, and so there are few useful diagnostic characters. Previous research has indicated the possibility of a cryptic species existing in P. procera in Colombia, despite there being no significant differences in wing color and pattern between the populations of the two putative species. Here we analyze the complexity and diversity of wing color patterns of individuals from five described Polythore species in the Central Amazon Basin of Peru using a novel suite of morphological analyses to quantify wing color and pattern: geometric morphometrics, chromaticity analysis, and Gabor wavelet transformation. We then test whether these color patterns are good predictors of species by recovering the phylogenetic relationships among the 5 species using the barcode gene (COI). Our results suggest that, while highly distinct and discrete wing patterns exist in Polythore, these "wingforms" do not represent monophyletic clades in the recovered topology. The wingforms identified as P. victoria and P. ornata are both involved in a polymorphism with P. neopicta; also, cryptic speciation may have taking place among individuals with the P. victoria wingform. Only P. aurora and P. spateri represent monophyletic species with a single wingform in our molecular phylogeny. We discuss the implications of this polymorphism, and the potential evolutionary mechanisms that could maintain it.
Harding, Kathleen M.; Ankrom, Nikole; Sherratt, Thomas N.; Hoffmann, Joachim; Van Gossum, Hans; Ware, Jessica L.; Cordero-Rivera, Adolfo
2015-01-01
The study of color polymorphisms (CP) has provided profound insights into the maintenance of genetic variation in natural populations. We here offer the first evidence for an elaborate wing polymorphism in the Neotropical damselfly genus Polythore, which consists of 21 described species, distributed along the eastern slopes of the Andes in South America. These damselflies display highly complex wing colors and patterning, incorporating black, white, yellow, and orange in multiple wing bands. Wing colors, along with some components of the male genitalia, have been the primary characters used in species description; few other morphological traits vary within the group, and so there are few useful diagnostic characters. Previous research has indicated the possibility of a cryptic species existing in P. procera in Colombia, despite there being no significant differences in wing color and pattern between the populations of the two putative species. Here we analyze the complexity and diversity of wing color patterns of individuals from five described Polythore species in the Central Amazon Basin of Peru using a novel suite of morphological analyses to quantify wing color and pattern: geometric morphometrics, chromaticity analysis, and Gabor wavelet transformation. We then test whether these color patterns are good predictors of species by recovering the phylogenetic relationships among the 5 species using the barcode gene (COI). Our results suggest that, while highly distinct and discrete wing patterns exist in Polythore, these “wingforms” do not represent monophyletic clades in the recovered topology. The wingforms identified as P. victoria and P. ornata are both involved in a polymorphism with P. neopicta; also, cryptic speciation may have taking place among individuals with the P. victoria wingform. Only P. aurora and P. spateri represent monophyletic species with a single wingform in our molecular phylogeny. We discuss the implications of this polymorphism, and the potential evolutionary mechanisms that could maintain it. PMID:25923455
Iwata, Masaki; Otaki, Joji M
2016-02-01
Complex butterfly wing color patterns are coordinated throughout a wing by unknown mechanisms that provide undifferentiated immature scale cells with positional information for scale color. Because there is a reasonable level of correspondence between the color pattern element and scale size at least in Junonia orithya and Junonia oenone, a single morphogenic signal may contain positional information for both color and size. However, this color-size relationship has not been demonstrated in other species of the family Nymphalidae. Here, we investigated the distribution patterns of scale size in relation to color pattern elements on the hindwings of the peacock pansy butterfly Junonia almana, together with other nymphalid butterflies, Vanessa indica and Danaus chrysippus. In these species, we observed a general decrease in scale size from the basal to the distal areas, although the size gradient was small in D. chrysippus. Scales of dark color in color pattern elements, including eyespot black rings, parafocal elements, and submarginal bands, were larger than those of their surroundings. Within an eyespot, the largest scales were found at the focal white area, although there were exceptional cases. Similarly, ectopic eyespots that were induced by physical damage on the J. almana background area had larger scales than in the surrounding area. These results are consistent with the previous finding that scale color and size coordinate to form color pattern elements. We propose a ploidy hypothesis to explain the color-size relationship in which the putative morphogenic signal induces the polyploidization (genome amplification) of immature scale cells and that the degrees of ploidy (gene dosage) determine scale color and scale size simultaneously in butterfly wings. Copyright © 2015 Elsevier Ltd. All rights reserved.
Color pattern evolution in Vanessa butterflies (Nymphalidae: Nymphalini): non-eyespot characters.
Abbasi, Roohollah; Marcus, Jeffrey M
2015-01-01
A phylogenetic approach was used to study color pattern evolution in Vanessa butterflies. Twenty-four color pattern elements from the Nymphalid ground plan were identified on the dorsal and ventral surfaces of the fore- and hind wings. Eyespot characters were excluded and will be examined elsewhere. The evolution of each character was traced over a Bayesian phylogeny of Vanessa reconstructed from 7750 DNA base pairs from 10 genes. Generally, the correspondence between character states on the same surface of the two wings is stronger on the ventral side compared to the dorsal side. The evolution of character states on both sides of a wing correspond with each other in most extant species, but the correspondence between dorsal and ventral character states is much stronger in the forewing than in the hindwing. The dorsal hindwing of many species of Vanessa is covered with an extended Basal Symmetry System and the Discalis I pattern element is highly variable between species, making this wing surface dissimilar to the other wing surfaces. The Basal Symmetry System and Discalis I may contribute to behavioral thermoregulation in Vanessa. Overall, interspecific directional character state evolution of non-eyespot color patterns is relatively rare in Vanessa, with a majority of color pattern elements showing non-variable, non-directional, or ambiguous character state evolution. The ease with which the development of color patterns can be modified, including character state reversals, has likely made important contributions to the production of color pattern diversity in Vanessa and other butterfly groups. © 2014 Wiley Periodicals, Inc.
Dhungel, Bidur; Otaki, Joji M
2009-11-01
Butterfly wing color patterns can be changed by the application of a temperature shock or pharmacological agents such as tungstate, producing a distinctive type of elemental modification called the TS (temperature shock) type. Heterochronic uncoupling between the signaling and reception steps during the color-pattern determination process has been proposed as a mechanism for TS-type changes. As an extension of this hypothesis, both the parafocal element (PFE) and the eyespot in the same wing compartment are considered to be determined by morphogenic signal(s) emitted from the same eyespot focus. However, these models need to be examined with additional experimental data. Furthermore, there is controversy as to whether the action of tungstate on wing color patterns is direct or Indirect. Using a species of nymphalid butterfly (Junonia orithya), we have devised a simple method for the local application of pharmacological agents directly on developing wings of pupae. Local tungstate application resulted in reduced eyespots and circular dislocated PFEs in the eyespot-less compartments only on the treated wing, demonstrating that tungstate directly induces color-pattern changes on wings. We further examined the eyespot-PFE relationship in normal and cold-shocked Individuals, showing that an eyespot can be superimposed on a PFE and vice versa, probably depending on the timing of their fate determination. Taken together, we propose a two-morphogen model for the normal color-pattern determination, in which the morphogenic signals for the eyespot and PFE are different from each other despite their Identical origin. This two-morphogen model is compatible with the heterochronic uncoupling model for TS-type changes.
Zhang, Linlin
2017-01-01
The optix gene has been implicated in butterfly wing pattern adaptation by genetic association, mapping, and expression studies. The actual developmental function of this gene has remained unclear, however. Here we used CRISPR/Cas9 genome editing to show that optix plays a fundamental role in nymphalid butterfly wing pattern development, where it is required for determination of all chromatic coloration. optix knockouts in four species show complete replacement of color pigments with melanins, with corresponding changes in pigment-related gene expression, resulting in black and gray butterflies. We also show that optix simultaneously acts as a switch gene for blue structural iridescence in some butterflies, demonstrating simple regulatory coordination of structural and pigmentary coloration. Remarkably, these optix knockouts phenocopy the recurring “black and blue” wing pattern archetype that has arisen on many independent occasions in butterflies. Here we demonstrate a simple genetic basis for structural coloration, and show that optix plays a deeply conserved role in butterfly wing pattern development. PMID:28923944
Zhang, Linlin; Mazo-Vargas, Anyi; Reed, Robert D
2017-10-03
The optix gene has been implicated in butterfly wing pattern adaptation by genetic association, mapping, and expression studies. The actual developmental function of this gene has remained unclear, however. Here we used CRISPR/Cas9 genome editing to show that optix plays a fundamental role in nymphalid butterfly wing pattern development, where it is required for determination of all chromatic coloration. optix knockouts in four species show complete replacement of color pigments with melanins, with corresponding changes in pigment-related gene expression, resulting in black and gray butterflies. We also show that optix simultaneously acts as a switch gene for blue structural iridescence in some butterflies, demonstrating simple regulatory coordination of structural and pigmentary coloration. Remarkably, these optix knockouts phenocopy the recurring "black and blue" wing pattern archetype that has arisen on many independent occasions in butterflies. Here we demonstrate a simple genetic basis for structural coloration, and show that optix plays a deeply conserved role in butterfly wing pattern development.
Otaki, Joji M
2008-07-01
A mechanistic understanding of the butterfly wing color-pattern determination can be facilitated by experimental pattern changes. Here I review physiologically induced color-pattern changes in nymphalid butterflies and their mechanistic and evolutionary implications. A type of color-pattern change can be elicited by elemental changes in size and position throughout the wing, as suggested by the nymphalid groundplan. These changes of pattern elements are bi-directional and bi-sided dislocation toward or away from eyespot foci and in both proximal and distal sides of the foci. The peripheral elements are dislocated even in the eyespot-less compartments. Anterior spots are more severely modified, suggesting the existence of an anterior-posterior gradient. In one species, eyespots are transformed into white spots with remnant-like orange scales, and such patterns emerge even at the eyespot-less "imaginary" foci. A series of these color-pattern modifications probably reveal "snap-shots" of a dynamic morphogenic signal due to heterochronic uncoupling between the signaling and reception steps. The conventional gradient model can be revised to account for these observed color-pattern changes.
Connahs, Heidi; Rhen, Turk; Simmons, Rebecca B
2016-03-31
Butterfly wing color patterns are an important model system for understanding the evolution and development of morphological diversity and animal pigmentation. Wing color patterns develop from a complex network composed of highly conserved patterning genes and pigmentation pathways. Patterning genes are involved in regulating pigment synthesis however the temporal expression dynamics of these interacting networks is poorly understood. Here, we employ next generation sequencing to examine expression patterns of the gene network underlying wing development in the nymphalid butterfly, Vanessa cardui. We identified 9, 376 differentially expressed transcripts during wing color pattern development, including genes involved in patterning, pigmentation and gene regulation. Differential expression of these genes was highest at the pre-ommochrome stage compared to early pupal and late melanin stages. Overall, an increasing number of genes were down-regulated during the progression of wing development. We observed dynamic expression patterns of a large number of pigment genes from the ommochrome, melanin and also pteridine pathways, including contrasting patterns of expression for paralogs of the yellow gene family. Surprisingly, many patterning genes previously associated with butterfly pattern elements were not significantly up-regulated at any time during pupation, although many other transcription factors were differentially expressed. Several genes involved in Notch signaling were significantly up-regulated during the pre-ommochrome stage including slow border cells, bunched and pebbles; the function of these genes in the development of butterfly wings is currently unknown. Many genes involved in ecdysone signaling were also significantly up-regulated during early pupal and late melanin stages and exhibited opposing patterns of expression relative to the ecdysone receptor. Finally, a comparison across four butterfly transcriptomes revealed 28 transcripts common to all four species that have no known homologs in other metazoans. This study provides a comprehensive list of differentially expressed transcripts during wing development, revealing potential candidate genes that may be involved in regulating butterfly wing patterns. Some differentially expressed genes have no known homologs possibly representing genes unique to butterflies. Results from this study also indicate that development of nymphalid wing patterns may arise not only from melanin and ommochrome pigments but also the pteridine pigment pathway.
Kusaba, Kiseki; Otaki, Joji M
2009-02-01
Butterfly wing color-patterns are a phenotypically coordinated array of scales whose color is determined as cellular interpretation outputs for morphogenic signals. Here we investigated distribution patterns of scale shape and size in relation to position and coloration on the hindwings of a nymphalid butterfly Junonia orithya. Most scales had a smooth edge but scales at and near the natural and ectopic eyespot foci and in the postbasal area were jagged. Scale size decreased regularly from the postbasal to distal areas, and eyespots occasionally had larger scales than the background. Reasonable correlations were obtained between the eyespot size and focal scale size in females. Histological and real-time individual observations of the color-pattern developmental sequence showed that the background brown and blue colors expanded from the postbasal to distal areas independently from the color-pattern elements such as eyespots. These data suggest that morphogenic signals for coloration directly or indirectly influence the scale shape and size and that the blue "background" is organized by a long-range signal from an unidentified organizing center in J. orithya.
Color pattern analysis of nymphalid butterfly wings: revision of the nymphalid groundplan.
Otaki, Joji M
2012-09-01
To better understand the developmental mechanisms of color pattern variation in butterfly wings, it is important to construct an accurate representation of pattern elements, known as the "nymphalid groundplan". However, some aspects of the current groundplan remain elusive. Here, I examined wing-wide elemental patterns of various nymphalid butterflies and confirmed that wing-wide color patterns are composed of the border, central, and basal symmetry systems. The central and basal symmetry systems can express circular patterns resembling eyespots, indicating that these systems have developmental mechanisms similar to those of the border symmetry system. The wing root band commonly occurs as a distinct symmetry system independent from the basal symmetry system. In addition, the marginal and submarginal bands are likely generated as a single system, referred to as the "marginal band system". Background spaces between two symmetry systems are sometimes light in coloration and can produce white bands, contributing significantly to color pattern diversity. When an element is enlarged with a pale central area, a visually similar (yet developmentally distinct) white band is produced. Based on the symmetric relationships of elements, I propose that both the central and border symmetry systems are comprised of "core elements" (the discal spot and the border ocelli, respectively) and a pair of "paracore elements" (the distal and proximal bands and the parafocal elements, respectively). Both core and paracore elements can be doubled, or outlined. Developmentally, this system configuration is consistent with the induction model, but not with the concentration gradient model for positional information.
Spontaneous long-range calcium waves in developing butterfly wings.
Ohno, Yoshikazu; Otaki, Joji M
2015-03-25
Butterfly wing color patterns emerge as the result of a regular arrangement of scales produced by epithelial scale cells at the pupal stage. These color patterns and scale arrangements are coordinated throughout the wing. However, the mechanism by which the development of scale cells is controlled across the entire wing remains elusive. In the present study, we used pupal wings of the blue pansy butterfly, Junonia orithya, which has distinct eyespots, to examine the possible involvement of Ca(2+) waves in wing development. Here, we demonstrate that the developing pupal wing tissue of the blue pansy butterfly displayed spontaneous low-frequency Ca(2+) waves in vivo that propagated slowly over long distances. Some waves appeared to be released from the immediate peripheries of the prospective eyespot and discal spot, though it was often difficult to identify the specific origins of these waves. Physical damage, which is known to induce ectopic eyespots, led to the radiation of Ca(2+) waves from the immediate periphery of the damaged site. Thapsigargin, which is a specific inhibitor of Ca(2+)-ATPases in the endoplasmic reticulum, induced an acute increase in cytoplasmic Ca(2+) levels and halted the spontaneous Ca(2+) waves. Additionally, thapsigargin-treated wings showed incomplete scale development as well as other scale and color pattern abnormalities. We identified a novel form of Ca(2+) waves, spontaneous low-frequency slow waves, which travel over exceptionally long distances. Our results suggest that spontaneous Ca(2+) waves play a critical role in the coordinated development of scale arrangements and possibly in color pattern formation in butterflies.
Molecular basis of wing coloration in a Batesian mimic butterfly, Papilio polytes
Nishikawa, Hideki; Iga, Masatoshi; Yamaguchi, Junichi; Saito, Kazuki; Kataoka, Hiroshi; Suzuki, Yutaka; Sugano, Sumio; Fujiwara, Haruhiko
2013-01-01
Batesian mimicry protects animals from predators through resemblance with distasteful models in shape, color pattern, or behavior. To elucidate the wing coloration mechanisms involved in the mimicry, we investigated chemical composition and gene expression of the pale yellow and red pigments of a swallowtail butterfly, Papilio polytes, whose females mimic the unpalatable butterfly Pachliopta aristolochiae. Using LC/MS, we showed that the pale yellow wing regions in non-mimetic females consist of kynurenine and N-β-alanyldopamine (NBAD). Moreover, qRT-PCR showed that kynurenine/NBAD biosynthetic genes were upregulated in these regions in non-mimetic females. However, these pigments were absent in mimetic females. RNA-sequencing showed that kynurenine/NBAD synthesis and Toll signaling genes were upregulated in the red spots specific to mimetic female wings. These results demonstrated that drastic changes in gene networks in the red and pale yellow regions can switch wing color patterns between non-mimetic and mimetic females of P. polytes. PMID:24212474
Molecular basis of wing coloration in a Batesian mimic butterfly, Papilio polytes.
Nishikawa, Hideki; Iga, Masatoshi; Yamaguchi, Junichi; Saito, Kazuki; Kataoka, Hiroshi; Suzuki, Yutaka; Sugano, Sumio; Fujiwara, Haruhiko
2013-11-11
Batesian mimicry protects animals from predators through resemblance with distasteful models in shape, color pattern, or behavior. To elucidate the wing coloration mechanisms involved in the mimicry, we investigated chemical composition and gene expression of the pale yellow and red pigments of a swallowtail butterfly, Papilio polytes, whose females mimic the unpalatable butterfly Pachliopta aristolochiae. Using LC/MS, we showed that the pale yellow wing regions in non-mimetic females consist of kynurenine and N-β-alanyldopamine (NBAD). Moreover, qRT-PCR showed that kynurenine/NBAD biosynthetic genes were upregulated in these regions in non-mimetic females. However, these pigments were absent in mimetic females. RNA-sequencing showed that kynurenine/NBAD synthesis and Toll signaling genes were upregulated in the red spots specific to mimetic female wings. These results demonstrated that drastic changes in gene networks in the red and pale yellow regions can switch wing color patterns between non-mimetic and mimetic females of P. polytes.
Character displacement in the fighting colours of Hetaerina damselflies.
Anderson, Christopher N; Grether, Gregory F
2010-12-07
Aggression between species is a seldom-considered but potentially widespread mechanism of character displacement in secondary sexual characters. Based on previous research showing that similarity in wing coloration directly influences interspecific territorial aggression in Hetaerina damselflies, we predicted that wing coloration would show a pattern of character displacement (divergence in sympatry). A geographical survey of four Hetaerina damselfly species in Mexico and Texas showed evidence for character displacement in both species pairs that regularly occurs sympatrically. Hetaerina titia, a species that typically has large black wing spots and small red wing spots, shifted to having even larger black spots and smaller red wing spots at sites where a congener with large red wing spots is numerically dominant (Hetaerina americana or Hetaerina occisa). Hetaerina americana showed the reverse pattern, shifting towards larger red wing spots where H. titia is numerically dominant. This pattern is consistent with the process of agonistic character displacement, but the ontogenetic basis of the shift remains to be demonstrated.
The marginal band system in nymphalid butterfly wings.
Taira, Wataru; Kinjo, Seira; Otaki, Joji M
2015-01-01
Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.
Otaki, Joji M; Ogasawara, Tsuyoshi; Yamamoto, Haruhiko
2005-06-01
Systemic injections of sodium tungstate, a protein-tyrosine phosphatase (PTPase) inhibitor, to pupae immediately after pupation have been shown to efficiently produce characteristic color-pattern modifications on the wings of many species of butterflies. Here we demonstrated that the tungstate-induced modification pattern was entirely different from other chemically-induced ones in a species of nymphalid butterfly Junonia (Precis) orithya. In this species, the systemic injections of tungstate produced characteristic expansion of black area and shrinkage of white area together with the move of parafocal elements toward the wing base. Overall, pattern boundaries became obscure. In contrast, an entirely different modification pattern, overall darkening of wings, was observed by the injections of stress-inducing chemicals, thapsigargin, ionomycin, or geldanamycin, to pupae under the rearing conditions for the adult summer form. On the ventral wings, this darkening was due to an increase of the proportion of peppered dark scales, which was reminiscent of the natural fall form of this species. Under the same rearing conditions, the injections of ecdysteroid, which is a well-known hormone being responsible for the seasonal polyphenism of nymphalid butterflies, yielded overall expansion of orange area especially around eyespots. Taken together, we conclude that the tungstate-induced modifications are clearly distinguishable from those of stress response and ecdysteroid effect. This conclusion then suggests that the putative PTPase signaling pathway that is sensitive to tungstate uniquely contributes to the wing-wide color-pattern development in butterflies.
The generation and diversification of butterfly eyespot color patterns.
Brunetti, C R; Selegue, J E; Monteiro, A; French, V; Brakefield, P M; Carroll, S B
2001-10-16
A fundamental challenge of evolutionary and developmental biology is understanding how new characters arise and change. The recently derived eyespots on butterfly wings vary extensively in number and pattern between species and play important roles in predator avoidance. Eyespots form through the activity of inductive organizers (foci) at the center of developing eyespot fields. Foci are the proposed source of a morphogen, the levels of which determine the color of surrounding wing scale cells. However, it is unknown how reception of the focal signal translates into rings of different-colored scales, nor how different color schemes arise in different species. We have identified several transcription factors, including butterfly homologs of the Drosophila Engrailed/Invected and Spalt proteins, that are deployed in concentric territories corresponding to the future rings of pigmented scales that compose the adult eyespot. We have isolated a new Bicyclus anynana wing pattern mutant, Goldeneye, in which the scales of one inner color ring become the color of a different ring. These changes correlate with shifts in transcription factor expression, suggesting that Goldeneye affects an early regulatory step in eyespot color patterning. In different butterfly species, the same transcription factors are expressed in eyespot fields, but in different relative spatial domains that correlate with divergent eyespot color schemes. Our results suggest that signaling from the focus induces nested rings of regulatory gene expression that subsequently control the final color pattern. Furthermore, the remarkably plastic regulatory interactions downstream of focal signaling have facilitated the evolution of eyespot diversity.
Convergent evolution in the genetic basis of Müllerian mimicry in heliconius butterflies.
Baxter, Simon W; Papa, Riccardo; Chamberlain, Nicola; Humphray, Sean J; Joron, Mathieu; Morrison, Clay; ffrench-Constant, Richard H; McMillan, W Owen; Jiggins, Chris D
2008-11-01
The neotropical butterflies Heliconius melpomene and H. erato are Müllerian mimics that display the same warningly colored wing patterns in local populations, yet pattern diversity between geographic regions. Linkage mapping has previously shown convergent red wing phenotypes in these species are controlled by loci on homologous chromosomes. Here, AFLP bulk segregant analysis using H. melpomene crosses identified genetic markers tightly linked to two red wing-patterning loci. These markers were used to screen a H. melpomene BAC library and a tile path was assembled spanning one locus completely and part of the second. Concurrently, a similar strategy was used to identify a BAC clone tightly linked to the locus controlling the mimetic red wing phenotypes in H. erato. A methionine rich storage protein (MRSP) gene was identified within this BAC clone, and comparative genetic mapping shows red wing color loci are in homologous regions of the genome of H. erato and H. melpomene. Subtle differences in these convergent phenotypes imply they evolved independently using somewhat different developmental routes, but are nonetheless regulated by the same switch locus. Genetic mapping of MRSP in a third related species, the "tiger" patterned H. numata, has no association with wing patterning and shows no evidence for genomic translocation of wing-patterning loci.
Sawada, H; Nakagoshi, M; Reinhardt, R K; Ziegler, I; Koch, P B
2002-06-01
Color patterns of butterfly wings are composed of single color points represented by each scale. In the case of Precis coenia, at the end of pupal development, different types of pigments are synthesized sequentially in the differently colored scales beginning with white (pterins) followed by red (ommatins) and then black (melanin). In order to explain how formation of these different colors is regulated, we examined the expression of an mRNA-encoding guanosine triphosphate-cyclohydrolase I (GTP-CH I; EC 3.5.4.16), the first key enzyme in the biosynthesis of pteridines, during pigment formation in the wings of P. coenia. The strongest positive signal was recognized around pigment formation one day before butterfly emergence. This GTP-CH I gene expression is paralleled by GTP-CH I enzyme activity measured in wing extracts. We also investigated the effect of 20-hydroxyecdysone on the expression of GTP-CH I mRNA and the enzyme activity during color formation. The results strongly suggest that the onset and duration of the expression of a GTP-CH I mRNA is triggered by a declining ecdysteroid hormone titer during late pupal development.
Neighboring genes shaping a single adaptive mimetic trait.
Pardo-Diaz, Carolina; Jiggins, Chris D
2014-01-01
The colorful wing patterns of Heliconius butterflies represent an excellent system in which to study the genetic and developmental control of adaptation and convergence. Using qRT-PCR and in situ hybridization on developing wings of the co-mimic species Heliconius melpomene and Heliconius erato, we have profiled the expression of three candidate genes located in the genomic locus controlling red color pattern variation. We found convergent domains of gene expression in H. melpomene and H. erato associated with red wing elements in the two genes optix and kinesin. During early pupal development of both species, the expression of optix perfectly associated with all red pattern elements whereas that of kinesin was specifically correlated with the presence of the red forewing band. These results provide evidence for the use of these two tightly linked patterning genes, acting together to create convergent wing phenotypes in Heliconius and constituting a hotspot of adaptation. © 2013 Wiley Periodicals, Inc.
Unique wing scale photonics of male Rajah Brooke's birdwing butterflies.
Wilts, Bodo D; Giraldo, Marco A; Stavenga, Doekele G
2016-01-01
Ultrastructures in butterfly wing scales can take many shapes, resulting in the often striking coloration of many butterflies due to interference of light. The plethora of coloration mechanisms is dazzling, but often only single mechanisms are described for specific animals. We have here investigated the male Rajah Brooke's birdwing, Trogonoptera brookiana, a large butterfly from Malaysia, which is marked by striking, colorful wing patterns. The dorsal side is decorated with large, iridescent green patterning, while the ventral side of the wings is primarily brown-black with small white, blue and green patches on the hindwings. Dense arrays of red hairs, creating a distinct collar as well as contrasting areas ventrally around the thorax, enhance the butterfly's beauty. The remarkable coloration is realized by a diverse number of intricate and complicated nanostructures in the hairs as well as the wing scales. The red collar hairs contain a broad-band absorbing pigment as well as UV-reflecting multilayers resembling the photonic structures of Morpho butterflies; the white wing patches consist of scales with prominent thin film reflectors; the blue patches have scales with ridge multilayers and these scales also have centrally concentrated melanin. The green wing areas consist of strongly curved scales, which possess a uniquely arranged photonic structure consisting of multilayers and melanin baffles that produces highly directional reflections. Rajah Brooke's birdwing employs a variety of structural and pigmentary coloration mechanisms to achieve its stunning optical appearance. The intriguing usage of order and disorder in related photonic structures in the butterfly wing scales may inspire novel optical materials as well as investigations into the development of these nanostructures in vivo.
Spectrally tuned structural and pigmentary coloration of birdwing butterfly wing scales.
Wilts, Bodo D; Matsushita, Atsuko; Arikawa, Kentaro; Stavenga, Doekele G
2015-10-06
The colourful wing patterns of butterflies play an important role for enhancing fitness; for instance, by providing camouflage, for interspecific mate recognition, or for aposematic display. Closely related butterfly species can have dramatically different wing patterns. The phenomenon is assumed to be caused by ecological processes with changing conditions, e.g. in the environment, and also by sexual selection. Here, we investigate the birdwing butterflies, Ornithoptera, the largest butterflies of the world, together forming a small genus in the butterfly family Papilionidae. The wings of these butterflies are marked by strongly coloured patches. The colours are caused by specially structured wing scales, which act as a chirped multilayer reflector, but the scales also contain papiliochrome pigments, which act as a spectral filter. The combined structural and pigmentary effects tune the coloration of the wing scales. The tuned colours are presumably important for mate recognition and signalling. By applying electron microscopy, (micro-)spectrophotometry and scatterometry we found that the various mechanisms of scale coloration of the different birdwing species strongly correlate with the taxonomical distribution of Ornithoptera species. © 2015 The Author(s).
Spectrally tuned structural and pigmentary coloration of birdwing butterfly wing scales
Wilts, Bodo D.; Matsushita, Atsuko; Arikawa, Kentaro; Stavenga, Doekele G.
2015-01-01
The colourful wing patterns of butterflies play an important role for enhancing fitness; for instance, by providing camouflage, for interspecific mate recognition, or for aposematic display. Closely related butterfly species can have dramatically different wing patterns. The phenomenon is assumed to be caused by ecological processes with changing conditions, e.g. in the environment, and also by sexual selection. Here, we investigate the birdwing butterflies, Ornithoptera, the largest butterflies of the world, together forming a small genus in the butterfly family Papilionidae. The wings of these butterflies are marked by strongly coloured patches. The colours are caused by specially structured wing scales, which act as a chirped multilayer reflector, but the scales also contain papiliochrome pigments, which act as a spectral filter. The combined structural and pigmentary effects tune the coloration of the wing scales. The tuned colours are presumably important for mate recognition and signalling. By applying electron microscopy, (micro-)spectrophotometry and scatterometry we found that the various mechanisms of scale coloration of the different birdwing species strongly correlate with the taxonomical distribution of Ornithoptera species. PMID:26446560
Wnt signaling underlies evolution and development of the butterfly wing pattern symmetry systems.
Martin, Arnaud; Reed, Robert D
2014-11-15
Most butterfly wing patterns are proposed to be derived from a set of conserved pattern elements known as symmetry systems. Symmetry systems are so-named because they are often associated with parallel color stripes mirrored around linear organizing centers that run between the anterior and posterior wing margins. Even though the symmetry systems are the most prominent and diverse wing pattern elements, their study has been confounded by a lack of knowledge regarding the molecular basis of their development, as well as the difficulty of drawing pattern homologies across species with highly derived wing patterns. Here we present the first molecular characterization of symmetry system development by showing that WntA expression is consistently associated with the major basal, discal, central, and external symmetry system patterns of nymphalid butterflies. Pharmacological manipulations of signaling gradients using heparin and dextran sulfate showed that pattern organizing centers correspond precisely with WntA, wingless, Wnt6, and Wnt10 expression patterns, thus suggesting a role for Wnt signaling in color pattern induction. Importantly, this model is supported by recent genetic and population genomic work identifying WntA as the causative locus underlying wing pattern variation within several butterfly species. By comparing the expression of WntA between nymphalid butterflies representing a range of prototypical symmetry systems, slightly deviated symmetry systems, and highly derived wing patterns, we were able to infer symmetry system homologies in several challenging cases. Our work illustrates how highly divergent morphologies can be derived from modifications to a common ground plan across both micro- and macro-evolutionary time scales. Copyright © 2014 Elsevier Inc. All rights reserved.
Wilts, Bodo D; Vey, Aidan J M; Briscoe, Adriana D; Stavenga, Doekele G
2017-11-21
Longwing butterflies, Heliconius sp., also called heliconians, are striking examples of diversity and mimicry in butterflies. Heliconians feature strongly colored patterns on their wings, arising from wing scales colored by pigments and/or nanostructures, which serve as an aposematic signal. Here, we investigate the coloration mechanisms among several species of Heliconius by applying scanning electron microscopy, (micro)spectrophotometry, and imaging scatterometry. We identify seven kinds of colored scales within Heliconius whose coloration is derived from pigments, nanostructures or both. In yellow-, orange- and red-colored wing patches, both cover and ground scales contain wavelength-selective absorbing pigments, 3-OH-kynurenine, xanthommatin and/or dihydroxanthommatin. In blue wing patches, the cover scales are blue either due to interference of light in the thin-film lower lamina (e.g., H. doris) or in the multilayered lamellae in the scale ridges (so-called ridge reflectors, e.g., H. sara and H. erato); the underlying ground scales are black. In the white wing patches, both cover and ground scales are blue due to their thin-film lower lamina, but because they are stacked upon each other and at the wing substrate, a faint bluish to white color results. Lastly, green wing patches (H. doris) have cover scales with blue-reflecting thin films and short-wavelength absorbing 3-OH-kynurenine, together causing a green color. The pigmentary and structural traits are discussed in relation to their phylogenetic distribution and the evolution of vision in this highly interesting clade of butterflies.
Wing shape allometry and aerodynamics in calopterygid damselflies: a comparative approach.
Outomuro, David; Adams, Dean C; Johansson, Frank
2013-06-07
Wing size and shape have important aerodynamic implications on flight performance. We explored how wing size was related to wing shape in territorial males of 37 taxa of the damselfly family Calopterygidae. Wing coloration was also included in the analyses because it is sexually and naturally selected and has been shown to be related to wing shape. We studied wing shape using both the non-dimensional radius of the second moment of wing area (RSM) and geometric morphometrics. Lower values of the RSM result in less energetically demanding flight and wider ranges of flight speed. We also re-analyzed previously published data on other damselflies and dragonflies. The RSM showed a hump-shaped relationship with wing size. However, after correcting for phylogeny using independent contrast, this pattern changed to a negative linear relationship. The basal genus of the study family, Hetaerina, was mainly driving that change. The obtained patterns were specific for the study family and differed from other damselflies and dragonflies. The relationship between the RSM and wing shape measured by geometric morphometrics was linear, but relatively small changes along the RSM axis can result in large changes in wing shape. Our results also showed that wing coloration may have some effect on RSM. We found that RSM showed a complex relationship with size in calopterygid damselflies, probably as a result of other selection pressures besides wing size per se. Wing coloration and specific behavior (e.g. courtship) are potential candidates for explaining the complexity. Univariate measures of wing shape such as RSM are more intuitive but lack the high resolution of other multivariate techniques such as geometric morphometrics. We suggest that the relationship between wing shape and size are taxa-specific and differ among closely-related insect groups.
Fukutomi, Yuichi; Matsumoto, Keiji; Agata, Kiyokazu; Funayama, Noriko; Koshikawa, Shigeyuki
2017-06-01
Various organisms have color patterns on their body surfaces, and these color patterns are thought to contribute to physiological regulation, communication with conspecifics, and signaling with the environment. An adult fly of Drosophila guttifera (Insecta: Diptera: Drosophilidae) has melanin pigmentation patterns on its body and wings. Though D. guttifera has been used for research into color pattern formation, how its pupal development proceeds and when the pigmentation starts have not been well studied. In this study, we defined the pupal stages of D. guttifera and measured the pigment content of wing spots from the pupal period to the period after eclosion. Using a transgenic line which carries eGFP connected with an enhancer of yellow, a gene necessary for melanin synthesis, we analyzed the timing at which the yellow enhancer starts to drive eGFP. We also analyzed the distribution of Yellow-producing cells, as indicated by the expression of eGFP during pupal and young adult periods. The results suggested that Yellow-producing cells were removed from wings within 3 h after eclosion, and wing pigmentation continued without epithelial cells. Furthermore, the results of vein cutting experiments showed that the transport of melanin precursors through veins was necessary for wing pigmentation. These results showed the importance of melanin precursors transported through veins and of extracellular factors which were secreted from epithelial cells and left in the cuticle.
Dhungel, Bidur; Ohno, Yoshikazu; Matayoshi, Rie; Otaki, Joji M
2013-03-25
Candidate genes for color pattern formation in butterfly wings have been known based on gene expression patterns since the 1990s, but their functions remain elusive due to a lack of a functional assay. Several methods of transferring and expressing a foreign gene in butterfly wings have been reported, but they have suffered from low success rates or low expression levels. Here, we developed a simple, practical method to efficiently deliver and express a foreign gene using baculovirus-mediated gene transfer in butterfly wings in vivo. A recombinant baculovirus containing a gene for green fluorescent protein (GFP) was injected into pupae of the blue pansy butterfly Junonia orithya (Nymphalidae). GFP fluorescence was detected in the pupal wings and other body parts of the injected individuals three to five days post-injection at various degrees of fluorescence. We obtained a high GFP expression rate at relatively high virus titers, but it was associated with pupal death before color pattern formation in wings. To reduce the high mortality rate caused by the baculovirus treatment, we administered an anti-gp64 antibody, which was raised against baculovirus coat protein gp64, to infected pupae after the baculovirus injection. This treatment greatly reduced the mortality rate of the infected pupae. GFP fluorescence was observed in pupal and adult wings and other body parts of the antibody-treated individuals at various degrees of fluorescence. Importantly, we obtained completely developed wings with a normal color pattern, in which fluorescent signals originated directly from scales or the basal membrane after the removal of scales. GFP fluorescence in wing tissues spatially coincided with anti-GFP antibody staining, confirming that the fluorescent signals originated from the expressed GFP molecules. Our baculovirus-mediated gene transfer system with an anti-gp64 antibody is reasonably efficient, and it can be an invaluable tool to transfer, express, and functionally examine foreign genes in butterfly wings and also in other non-model insect systems.
Wing shape variation associated with mimicry in butterflies.
Jones, Robert T; Le Poul, Yann; Whibley, Annabel C; Mérot, Claire; ffrench-Constant, Richard H; Joron, Mathieu
2013-08-01
Mimetic resemblance in unpalatable butterflies has been studied by evolutionary biologists for over a century, but has largely focused on the convergence in wing color patterns. In Heliconius numata, discrete color-pattern morphs closely resemble comimics in the distantly related genus Melinaea. We examine the possibility that the shape of the butterfly wing also shows adaptive convergence. First, simple measures of forewing dimensions were taken of individuals in a cross between H. numata morphs, and showed quantitative differences between two of the segregating morphs, f. elegans and f. silvana. Second, landmark-based geometric morphometric and elliptical Fourier outline analyses were used to more fully characterize these shape differences. Extension of these techniques to specimens from natural populations suggested that, although many of the coexisting morphs could not be discriminated by shape, the differences we identified between f. elegans and f. silvana hold in the wild. Interestingly, despite extensive overlap, the shape variation between these two morphs is paralleled in their respective Melinaea comimics. Our study therefore suggests that wing-shape variation is associated with mimetic resemblance, and raises the intriguing possibility that the supergene responsible for controlling the major switch in color pattern between morphs also contributes to wing shape differences in H. numata. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
Wing patterning gene redefines the mimetic history of Heliconius butterflies.
Hines, Heather M; Counterman, Brian A; Papa, Riccardo; Albuquerque de Moura, Priscila; Cardoso, Marcio Z; Linares, Mauricio; Mallet, James; Reed, Robert D; Jiggins, Chris D; Kronforst, Marcus R; McMillan, W Owen
2011-12-06
The mimetic butterflies Heliconius erato and Heliconius melpomene have undergone parallel radiations to form a near-identical patchwork of over 20 different wing-pattern races across the Neotropics. Previous molecular phylogenetic work on these radiations has suggested that similar but geographically disjunct color patterns arose multiple times independently in each species. The neutral markers used in these studies, however, can move freely across color pattern boundaries, and therefore might not represent the history of the adaptive traits as accurately as markers linked to color pattern genes. To assess the evolutionary histories across different loci, we compared relationships among races within H. erato and within H. melpomene using a series of unlinked genes, genes linked to color pattern loci, and optix, a gene recently shown to control red color-pattern variation. We found that although unlinked genes partition populations by geographic region, optix had a different history, structuring lineages by red color patterns and supporting a single origin of red-rayed patterns within each species. Genes closely linked (80-250 kb) to optix exhibited only weak associations with color pattern. This study empirically demonstrates the necessity of examining phenotype-determining genomic regions to understand the history of adaptive change in rapidly radiating lineages. With these refined relationships, we resolve a long-standing debate about the origins of the races within each species, supporting the hypothesis that the red-rayed Amazonian pattern evolved recently and expanded, causing disjunctions of more ancestral patterns.
Live Cell Imaging of Butterfly Pupal and Larval Wings In Vivo
Ohno, Yoshikazu; Otaki, Joji M.
2015-01-01
Butterfly wing color patterns are determined during the late larval and early pupal stages. Characterization of wing epithelial cells at these stages is thus critical to understand how wing structures, including color patterns, are determined. Previously, we successfully recorded real-time in vivo images of developing butterfly wings over time at the tissue level. In this study, we employed similar in vivo fluorescent imaging techniques to visualize developing wing epithelial cells in the late larval and early pupal stages 1 hour post-pupation. Both larval and pupal epithelial cells were rich in mitochondria and intracellular networks of endoplasmic reticulum, suggesting high metabolic activities, likely in preparation for cellular division, polyploidization, and differentiation. Larval epithelial cells in the wing imaginal disk were relatively large horizontally and tightly packed, whereas pupal epithelial cells were smaller and relatively loosely packed. Furthermore, larval cells were flat, whereas pupal cells were vertically elongated as deep as 130 μm. In pupal cells, many endosome-like or autophagosome-like structures were present in the cellular periphery down to approximately 10 μm in depth, and extensive epidermal feet or filopodia-like processes were observed a few micrometers deep from the cellular surface. Cells were clustered or bundled from approximately 50 μm in depth to deeper levels. From 60 μm to 80 μm in depth, horizontal connections between these clusters were observed. The prospective eyespot and marginal focus areas were resistant to fluorescent dyes, likely because of their non-flat cone-like structures with a relatively thick cuticle. These in vivo images provide important information with which to understand processes of epithelial cell differentiation and color pattern determination in butterfly wings. PMID:26107809
Live Cell Imaging of Butterfly Pupal and Larval Wings In Vivo.
Ohno, Yoshikazu; Otaki, Joji M
2015-01-01
Butterfly wing color patterns are determined during the late larval and early pupal stages. Characterization of wing epithelial cells at these stages is thus critical to understand how wing structures, including color patterns, are determined. Previously, we successfully recorded real-time in vivo images of developing butterfly wings over time at the tissue level. In this study, we employed similar in vivo fluorescent imaging techniques to visualize developing wing epithelial cells in the late larval and early pupal stages 1 hour post-pupation. Both larval and pupal epithelial cells were rich in mitochondria and intracellular networks of endoplasmic reticulum, suggesting high metabolic activities, likely in preparation for cellular division, polyploidization, and differentiation. Larval epithelial cells in the wing imaginal disk were relatively large horizontally and tightly packed, whereas pupal epithelial cells were smaller and relatively loosely packed. Furthermore, larval cells were flat, whereas pupal cells were vertically elongated as deep as 130 μm. In pupal cells, many endosome-like or autophagosome-like structures were present in the cellular periphery down to approximately 10 μm in depth, and extensive epidermal feet or filopodia-like processes were observed a few micrometers deep from the cellular surface. Cells were clustered or bundled from approximately 50 μm in depth to deeper levels. From 60 μm to 80 μm in depth, horizontal connections between these clusters were observed. The prospective eyespot and marginal focus areas were resistant to fluorescent dyes, likely because of their non-flat cone-like structures with a relatively thick cuticle. These in vivo images provide important information with which to understand processes of epithelial cell differentiation and color pattern determination in butterfly wings.
2013-01-01
Background Candidate genes for color pattern formation in butterfly wings have been known based on gene expression patterns since the 1990s, but their functions remain elusive due to a lack of a functional assay. Several methods of transferring and expressing a foreign gene in butterfly wings have been reported, but they have suffered from low success rates or low expression levels. Here, we developed a simple, practical method to efficiently deliver and express a foreign gene using baculovirus-mediated gene transfer in butterfly wings in vivo. Results A recombinant baculovirus containing a gene for green fluorescent protein (GFP) was injected into pupae of the blue pansy butterfly Junonia orithya (Nymphalidae). GFP fluorescence was detected in the pupal wings and other body parts of the injected individuals three to five days post-injection at various degrees of fluorescence. We obtained a high GFP expression rate at relatively high virus titers, but it was associated with pupal death before color pattern formation in wings. To reduce the high mortality rate caused by the baculovirus treatment, we administered an anti-gp64 antibody, which was raised against baculovirus coat protein gp64, to infected pupae after the baculovirus injection. This treatment greatly reduced the mortality rate of the infected pupae. GFP fluorescence was observed in pupal and adult wings and other body parts of the antibody-treated individuals at various degrees of fluorescence. Importantly, we obtained completely developed wings with a normal color pattern, in which fluorescent signals originated directly from scales or the basal membrane after the removal of scales. GFP fluorescence in wing tissues spatially coincided with anti-GFP antibody staining, confirming that the fluorescent signals originated from the expressed GFP molecules. Conclusions Our baculovirus-mediated gene transfer system with an anti-gp64 antibody is reasonably efficient, and it can be an invaluable tool to transfer, express, and functionally examine foreign genes in butterfly wings and also in other non-model insect systems. PMID:23522444
Genomic architecture of adaptive color pattern divergence and convergence in Heliconius butterflies
Supple, Megan A.; Hines, Heather M.; Dasmahapatra, Kanchon K.; Lewis, James J.; Nielsen, Dahlia M.; Lavoie, Christine; Ray, David A.; Salazar, Camilo; McMillan, W. Owen; Counterman, Brian A.
2013-01-01
Identifying the genetic changes driving adaptive variation in natural populations is key to understanding the origins of biodiversity. The mosaic of mimetic wing patterns in Heliconius butterflies makes an excellent system for exploring adaptive variation using next-generation sequencing. In this study, we use a combination of techniques to annotate the genomic interval modulating red color pattern variation, identify a narrow region responsible for adaptive divergence and convergence in Heliconius wing color patterns, and explore the evolutionary history of these adaptive alleles. We use whole genome resequencing from four hybrid zones between divergent color pattern races of Heliconius erato and two hybrid zones of the co-mimic Heliconius melpomene to examine genetic variation across 2.2 Mb of a partial reference sequence. In the intergenic region near optix, the gene previously shown to be responsible for the complex red pattern variation in Heliconius, population genetic analyses identify a shared 65-kb region of divergence that includes several sites perfectly associated with phenotype within each species. This region likely contains multiple cis-regulatory elements that control discrete expression domains of optix. The parallel signatures of genetic differentiation in H. erato and H. melpomene support a shared genetic architecture between the two distantly related co-mimics; however, phylogenetic analysis suggests mimetic patterns in each species evolved independently. Using a combination of next-generation sequencing analyses, we have refined our understanding of the genetic architecture of wing pattern variation in Heliconius and gained important insights into the evolution of novel adaptive phenotypes in natural populations. PMID:23674305
Adhikari, Kiran; Otaki, Joji M
2016-02-01
It is often desirable but difficult to retrieve information on the mature phenotype of an immature tissue sample that has been subjected to gene expression analysis. This problem cannot be ignored when individual variation within a species is large. To circumvent this problem in the butterfly wing system, we developed a new surgical method for removing a single forewing from a pupa using Junonia orithya; the operated pupa was left to develop to an adult without eclosion. The removed right forewing was subjected to gene expression analysis, whereas the non-removed left forewing was examined for color patterns. As a test case, we focused on Distal-less (Dll), which likely plays an active role in inducing elemental patterns, including eyespots. The Dll expression level in forewings was paired with eyespot size data from the same individual. One third of the operated pupae survived and developed wing color patterns. Dll expression levels were significantly higher in males than in females, although male eyespots were smaller in size than female eyespots. Eyespot size data showed weak but significant correlations with the Dll expression level in females. These results demonstrate that a single-wing removal method was successfully applied to the butterfly wing system and suggest the weak and non-exclusive contribution of Dll to eyespot size determination in this butterfly. Our novel methodology for establishing correspondence between gene expression and phenotype can be applied to other candidate genes for color pattern development in butterflies. Conceptually similar methods may also be applicable in other developmental systems.
Keeping the band together: evidence for false boundary disruptive coloration in a butterfly.
Seymoure, B M; Aiello, A
2015-09-01
There is a recent surge of evidence supporting disruptive coloration, in which patterns break up the animal's outline through false edges or boundaries, increasing survival in animals by reducing predator detection and/or preventing recognition. Although research has demonstrated that false edges are successful for reducing predation of prey, research into the role of internal false boundaries (i.e. stripes and bands) in reducing predation remains warranted. Many animals have stripes and bands that may function disruptively. Here, we test the possible disruptive function of wing band patterning in a butterfly, Anartia fatima, using artificial paper and plasticine models in Panama. We manipulated the band so that one model type had the band shifted to the wing margin (nondisruptive treatment) and another model had a discontinuous band located on the wing margin (discontinuous edge treatment). We kept the natural wing pattern to represent the false boundary treatment. Across all treatment groups, we standardized the area of colour and used avian visual models to confirm a match between manipulated and natural wing colours. False boundary models had higher survival than either the discontinuous edge model or the nondisruptive model. There was no survival difference between the discontinuous edge model and the nondisruptive model. Our results demonstrate the importance of wing bands in reducing predation on butterflies and show that markings set in from the wing margin can reduce predation more effectively than marginal bands and discontinuous marginal patterns. This study demonstrates an adaptive benefit of having stripes and bands. © 2015 European Society For Evolutionary Biology.
Optical diffraction by the microstructure of the wing of a moth
NASA Astrophysics Data System (ADS)
Brink, D. J.; Smit, J. E.; Lee, M. E.; Möller, A.
1995-09-01
On the wing of the moth Trichoplusia orichalcea a prominent, apparently highly reflective, golden spot can be seen. Scales from this area of the wing exhibit a regular microstructure resembling a submicrometer herringbone pattern. We show that a diffraction process from this structure is responsible for the observed optical properties, such as directionality, brightness variations, polarization, and color.
Chazot, Nicolas; Panara, Stephen; Zilbermann, Nicolas; Blandin, Patrick; Le Poul, Yann; Cornette, Raphaël; Elias, Marianne; Debat, Vincent
2016-01-01
Butterfly wings harbor highly diverse phenotypes and are involved in many functions. Wing size and shape result from interactions between adaptive processes, phylogenetic history, and developmental constraints, which are complex to disentangle. Here, we focus on the genus Morpho (Nymphalidae: Satyrinae, 30 species), which presents a high diversity of sizes, shapes, and color patterns. First, we generate a comprehensive molecular phylogeny of these 30 species. Next, using 911 collection specimens, we quantify the variation of wing size and shape across species, to assess the importance of shared ancestry, microhabitat use, and sexual selection in the evolution of the wings. While accounting for phylogenetic and allometric effects, we detect a significant difference in wing shape but not size among microhabitats. Fore and hindwings covary at the individual and species levels, and the covariation differs among microhabitats. However, the microhabitat structure in covariation disappears when phylogenetic relationships are taken into account. Our results demonstrate that microhabitat has driven wing shape evolution, although it has not strongly affected forewing and hindwing integration. We also found that sexual dimorphism of forewing shape and color pattern are coupled, suggesting a common selective force. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
An introgressed wing pattern acts as a mating cue.
Sánchez, Angela P; Pardo-Diaz, Carolina; Enciso-Romero, Juan; Muñoz, Astrid; Jiggins, Chris D; Salazar, Camilo; Linares, Mauricio
2015-06-01
Heliconius butterflies provide good examples of both homoploid hybrid speciation and ecological speciation. In particular, examples of adaptive introgression have been detected among the subspecies of Heliconius timareta, which acquired red color pattern elements from H. melpomene. We tested whether the introgression of red wing pattern elements into H. timareta florencia might also be associated with incipient reproductive isolation (RI) from its close relative, H. timareta subsp. nov., found in the eastern Andes. No choice experiments show a 50% reduction in mating between females of H. t. subsp. nov. and males of H .t. florencia, but not in the reciprocal direction. In choice experiments using wing models, males of H. timareta subsp. nov. approach and court red phenotypes less than their own, whereas males of H. t. florencia prefer models with a red phenotype. Intrinsic postzygotic isolation was not detected in crosses between these H. timareta races. These results suggest that a color pattern trait gained by introgression is triggering RI between H. timareta subsp. nov. and H. t. florencia. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Iwata, Masaki; Ohno, Yoshikazu; Otaki, Joji M.
2014-01-01
Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the cellular dynamics of living wing tissues in butterflies. PMID:24586829
Iwata, Masaki; Ohno, Yoshikazu; Otaki, Joji M
2014-01-01
Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the cellular dynamics of living wing tissues in butterflies.
Taira, Wataru; Otaki, Joji M
2016-01-01
Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.
Taira, Wataru; Otaki, Joji M.
2016-01-01
Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns. PMID:26731532
Wingless is a positive regulator of eyespot color patterns in Bicyclus anynana butterflies.
Özsu, Nesibe; Chan, Qian Yi; Chen, Bin; Gupta, Mainak Das; Monteiro, Antónia
2017-09-01
Eyespot patterns of nymphalid butterflies are an example of a novel trait yet, the developmental origin of eyespots is still not well understood. Several genes have been associated with eyespot development but few have been tested for function. One of these genes is the signaling ligand, wingless, which is expressed in the eyespot centers during early pupation and may function in eyespot signaling and color ring differentiation. Here we tested the function of wingless in wing and eyespot development by down-regulating it in transgenic Bicyclus anynana butterflies via RNAi driven by an inducible heat-shock promoter. Heat-shocks applied during larval and early pupal development led to significant decreases in wingless mRNA levels and to decreases in eyespot size and wing size in adult butterflies. We conclude that wingless is a positive regulator of eyespot and wing development in B. anynana butterflies. Copyright © 2017 Elsevier Inc. All rights reserved.
Su, Shiyu; Lim, Matthew; Kunte, Krushnamegh
2015-11-01
Predation exerts strong selection on mimetic butterfly wing color patterns, which also serve other functions such as sexual selection. Therefore, specific selection pressures may affect the sexes and signal components differentially. We tested three predictions about the evolution of mimetic resemblance by comparing wing coloration of aposematic butterflies and their Batesian mimics: (a) females gain greater mimetic advantage than males and therefore are better mimics, (b) due to intersexual genetic correlations, sexually monomorphic mimics are better mimics than female-limited mimics, and (c) mimetic resemblance is better on the dorsal wing surface that is visible to predators in flight. Using a physiological model of avian color vision, we quantified mimetic resemblance from predators' perspective, which showed that female butterflies were better mimics than males. Mimetic resemblance in female-limited mimics was comparable to that in sexually monomorphic mimics, suggesting that intersexual genetic correlations did not constrain adaptive response to selection for female-limited mimicry. Mimetic resemblance on the ventral wing surface was better than that on the dorsal wing surface, implying stronger natural and sexual selection on ventral and dorsal surfaces, respectively. These results suggest that mimetic resemblance in butterfly mimicry rings has evolved under various selective pressures acting in a sex- and wing surface-specific manner. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Hoyal Cuthill, Jennifer F; Charleston, Michael
2015-12-01
Examples of long-term coevolution are rare among free-living organisms. Müllerian mimicry in Heliconius butterflies had been suggested as a key example of coevolution by early genetic studies. However, research over the last two decades has been dominated by the idea that the best-studied comimics, H. erato and H. melpomene, did not coevolve at all. Recently sequenced genes associated with wing color pattern phenotype offer a new opportunity to resolve this controversy. Here, we test the hypothesis of coevolution between H. erato and H. melpomene using Bayesian multilocus analysis of five color pattern genes and five neutral genetic markers. We first explore the extent of phylogenetic agreement versus conflict between the different genes. Coevolution is then tested against three aspects of the mimicry diversifications: phylogenetic branching patterns, divergence times, and, for the first time, phylogeographic histories. We show that all three lines of evidence are compatible with strict coevolution of the diverse mimicry wing patterns, contrary to some recent suggestions. Instead, these findings tally with a coevolutionary diversification driven primarily by the ecological force of Müllerian mimicry. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Dynamics of F-actin prefigure the structure of butterfly wing scales.
Dinwiddie, April; Null, Ryan; Pizzano, Maria; Chuong, Lisa; Leigh Krup, Alexis; Ee Tan, Hwei; Patel, Nipam H
2014-08-15
The wings of butterflies and moths consist of dorsal and ventral epidermal surfaces that give rise to overlapping layers of scales and hairs (Lepidoptera, "scale wing"). Wing scales (average length ~200 µm) are homologous to insect bristles (macrochaetes), and their colors create the patterns that characterize lepidopteran wings. The topology and surface sculpture of wing scales vary widely, and this architectural complexity arises from variations in the developmental program of the individual scale cells of the wing epithelium. One of the more striking features of lepidopteran wing scales are the longitudinal ridges that run the length of the mature (dead) cell, gathering the cuticularized scale cell surface into pleats on the sides of each scale. While also present around the periphery of other insect bristles and hairs, longitudinal ridges in lepidopteran wing scales gain new significance for their creation of iridescent color through microribs and lamellae. Here we show the dynamics of the highly organized F-actin filaments during scale cell development, and present experimental manipulations of actin polymerization that reveal the essential role of this cytoskeletal component in wing scale elongation and the positioning of longitudinal ribs. Copyright © 2014 Elsevier Inc. All rights reserved.
Johnson, Haley; Solensky, Michelle J.; Satterfield, Dara A.; Davis, Andrew K.
2014-01-01
In animals with complex life cycles, all resources needed to form adult tissues are procured at the larval stage. For butterflies, the proper development of wings involves synthesizing tissue during metamorphosis based on the raw materials obtained by larvae. Similarly, manufacture of pigment for wing scales also requires resources acquired by larvae. We conducted an experiment to test the effects of food deprivation in the larval stage on multiple measures of adult wing morphology and coloration of monarch butterflies (Danaus plexippus), a species in which long-distance migration makes flight efficiency critical. In a captive setting, we restricted food (milkweed) from late-stage larvae for either 24 hrs or 48 hrs, then after metamorphosis we used image analysis methods to measure forewing surface area and elongation (length/width), which are both important for migration. We also measured the brightness of orange pigment and the intensity of black on the wing. There were correlations between several wing features, including an unexpected association between wing elongation and melanism, which will require further study to fully understand. The clearest effect of food restriction was a reduction in adult wing size in the high stress group (by approximately 2%). Patterns observed for other wing traits were ambiguous: monarchs in the low stress group (but not the high) had less elongated and paler orange pigmentation. There was no effect on wing melanism. Although some patterns obtained in this study were unclear, our results concerning wing size have direct bearing on the monarch migration. We show that if milkweed is limited for monarch larvae, their wings become stunted, which could ultimately result in lower migration success. PMID:24695643
Johnson, Haley; Solensky, Michelle J; Satterfield, Dara A; Davis, Andrew K
2014-01-01
In animals with complex life cycles, all resources needed to form adult tissues are procured at the larval stage. For butterflies, the proper development of wings involves synthesizing tissue during metamorphosis based on the raw materials obtained by larvae. Similarly, manufacture of pigment for wing scales also requires resources acquired by larvae. We conducted an experiment to test the effects of food deprivation in the larval stage on multiple measures of adult wing morphology and coloration of monarch butterflies (Danaus plexippus), a species in which long-distance migration makes flight efficiency critical. In a captive setting, we restricted food (milkweed) from late-stage larvae for either 24 hrs or 48 hrs, then after metamorphosis we used image analysis methods to measure forewing surface area and elongation (length/width), which are both important for migration. We also measured the brightness of orange pigment and the intensity of black on the wing. There were correlations between several wing features, including an unexpected association between wing elongation and melanism, which will require further study to fully understand. The clearest effect of food restriction was a reduction in adult wing size in the high stress group (by approximately 2%). Patterns observed for other wing traits were ambiguous: monarchs in the low stress group (but not the high) had less elongated and paler orange pigmentation. There was no effect on wing melanism. Although some patterns obtained in this study were unclear, our results concerning wing size have direct bearing on the monarch migration. We show that if milkweed is limited for monarch larvae, their wings become stunted, which could ultimately result in lower migration success.
Rhen, Turk; Simmons, Rebecca B.
2016-01-01
Butterfly eyespots are complex morphological traits that can vary in size, shape and color composition even on the same wing surface. Homology among eyespots suggests they share a common developmental basis and function as an integrated unit in response to selection. Despite strong evidence of genetic integration, eyespots can also exhibit modularity or plasticity, indicating an underlying flexibility in pattern development. The extent to which particular eyespots or eyespot color elements exhibit modularity or integration is poorly understood, particularly following exposure to novel conditions. We used perturbation experiments to explore phenotypic correlations among different eyespots and their color elements on the ventral hindwing of V. cardui. Specifically, we identified which eyespots and eyespot features are most sensitive to perturbation by heat shock and injection of heparin—a cold shock mimic. For both treatments, the two central eyespots (3 + 4) were most affected by the experimental perturbations, whereas the outer eyespot border was more resistant to modification than the interior color elements. Overall, the individual color elements displayed a similar response to heat shock across all eyespots, but varied in their response to each other. Graphical modeling also revealed that although eyespots differ morphologically, regulation of eyespot size and colored elements appear to be largely integrated across the wing. Patterns of integration, however, were disrupted following heat shock, revealing that the strength of integration varies across the wing and is strongest between the two central eyespots. These findings support previous observations that document coupling between eyespots 3 + 4 in other nymphalid butterflies. PMID:27560365
Connahs, Heidi; Rhen, Turk; Simmons, Rebecca B
2016-01-01
Butterfly eyespots are complex morphological traits that can vary in size, shape and color composition even on the same wing surface. Homology among eyespots suggests they share a common developmental basis and function as an integrated unit in response to selection. Despite strong evidence of genetic integration, eyespots can also exhibit modularity or plasticity, indicating an underlying flexibility in pattern development. The extent to which particular eyespots or eyespot color elements exhibit modularity or integration is poorly understood, particularly following exposure to novel conditions. We used perturbation experiments to explore phenotypic correlations among different eyespots and their color elements on the ventral hindwing of V. cardui. Specifically, we identified which eyespots and eyespot features are most sensitive to perturbation by heat shock and injection of heparin-a cold shock mimic. For both treatments, the two central eyespots (3 + 4) were most affected by the experimental perturbations, whereas the outer eyespot border was more resistant to modification than the interior color elements. Overall, the individual color elements displayed a similar response to heat shock across all eyespots, but varied in their response to each other. Graphical modeling also revealed that although eyespots differ morphologically, regulation of eyespot size and colored elements appear to be largely integrated across the wing. Patterns of integration, however, were disrupted following heat shock, revealing that the strength of integration varies across the wing and is strongest between the two central eyespots. These findings support previous observations that document coupling between eyespots 3 + 4 in other nymphalid butterflies.
Otaki, Joji M
2011-06-01
Butterfly wing color patterns consist of many color-pattern elements such as eyespots. It is believed that eyespot patterns are determined by a concentration gradient of a single morphogen species released by diffusion from the prospective eyespot focus in conjunction with multiple thresholds in signal-receiving cells. As alternatives to this single-morphogen model, more flexible multiple-morphogen model and induction model can be proposed. However, the relevance of these conceptual models to actual eyespots has not been examined systematically. Here, representative eyespots from nymphalid butterflies were analyzed morphologically to determine if they are consistent with these models. Measurement of ring widths of serial eyespots from a single wing surface showed that the proportion of each ring in an eyespot is quite different among homologous rings of serial eyespots of different sizes. In asymmetric eyespots, each ring is distorted to varying degrees. In extreme cases, only a portion of rings is expressed remotely from the focus. Similarly, there are many eyespots where only certain rings are deleted, added, or expanded. In an unusual case, the central area of an eyespot is composed of multiple "miniature eyespots," but the overall macroscopic eyespot structure is maintained. These results indicate that each eyespot ring has independence and flexibility to a certain degree, which is less consistent with the single-morphogen model. Considering a "periodic eyespot", which has repeats of a set of rings, damage-induced eyespots in mutants, and a scale-size distribution pattern in an eyespot, the induction model is the least incompatible with the actual eyespot diversity.
Koch, P Bernhardt; Nijhout, H Frederik
1990-05-01
A set of stage specific proteins of approximally 86 to 90 kDal are synthesized by isolated wings ofPrecis coenia on day 5 of the pupal stage. They are named "B proteins". They are synthesized in presumptive black wing areas in higher amounts than in presumptive white wing areas and are the major proteins synthesized on day 5. Wings from 5 days old pupae, which were incubated with 35 S-methionine for 2 or 4 hours, incorporate radiolabel into presumptive black pattern elements. This is probably due to the localized synthesis of the above mentioned proteins. Injection of 35 S-methionine into whole pupae on day 5 resulted in the labelling of the mature black and grey scales but not white scales. This radiolabel incorporation pattern corresponds exactly to the incorporation of the melanin precursor 14 C-tyrosine into the scales. The results indicate that the "B proteins" are specifically related to the formation of black and grey portions of thePrecis wing pattern. Injection of 35 S-methionine into whole pupae on day 6 resulted in the labelling of the mature red scales probably due to labelling of "R proteins", which may be involved in the formation of red pattern elements.
Reflection characterization of nano-sized dielectric structure in Morpho butterfly wings
NASA Astrophysics Data System (ADS)
Zhu, Dong
2017-10-01
Morpho butterflies living in Central and South America are well-known for their structural-colored blue wings. The blue coloring originates from the interaction of light with nano-sized dielectric structures that are equipped on the external surface of scales covering over their wings. The high-accuracy nonstandard finite-difference time domain (NS-FDTD) method is used to investigate the reflection characterization from the nanostructures. In the NS-FDTD calculation, a computational model is built to mimic the actual tree-like multilayered structures wherever possible using the hyperbolic tangent functions. It is generally known that both multilayer interference and diffraction grating phenomena can occur when light enters the nano-sized multilayered structure. To answer the question that which phenomenon is mainly responsible for the blue coloring, the NS-FDTD calculation is performed under various incidence angles at wavelengths from 360 to 500 nm. The calculated results at one incident wavelength under different incidence angles are visualized in a two-dimensional mapping image, where horizontal and vertical axes are incidence and reflection angles, respectively. The images demonstrate a remarkable transition from a ring-like pattern at shorter wavelengths to a retro-reflection pattern at longer wavelengths. To clarify the origin of the pattern transition, the model is separated into several simpler parts and compared their mapping images with the theoretical diffraction calculations. It can be concluded that the blue coloring at longer wavelengths is mainly caused by the cooperation of multilayer interference and retro-reflection while the effect of diffraction grating is predominant at shorter wavelengths.
2012-01-01
16.64 Figure 3. Venation map of Manduca sexta forewing [11]. 2.4. Venation Insect wings are formed from a complex makeup of polymer based chains, Chitin ...for coloration, but may subtly influence flow patterns and boundary layer structure over wings [4, 24]. There is significant understanding of chitin ...biological specimen to vary the bonding chains, assemblage of nanofibers and crystalline structure, the material properties of chitin can vary over a
Selective chromatid segregation mechanism for Bruchus wings piebald color.
Klar, Amar J S
2015-01-01
The mechanisms of asymmetric organ development have been under intensive investigation for years, yet the proposed mechanisms remain controversial (1-3). The female Bruchus quadrimaculatus beetle insect develops two black-colored spots bilaterally located on each upper elytra wing by an unknown mechanism. Fifty percent of the P (for piebald, two colors) gene homozygous mutant insects, described in 1925, had a normal left elytrum (with two black spots) and an abnormal right elytrum (with two red spots) and the balance supported the converse lateralized pigment arrangement (4). Rather than supporting the conventional morphogen model for the wings pigmentation development, their biological origin is explained here with the somatic strand-specific epigenetic imprinting and selective sister chromatid segregation (SSIS) mechanism (5). We propose that the P gene product performs the selective sister chromatid segregation function to produce symmetric cell division of a specific cell during embryogenesis to result in the bilateral symmetric development of elytra black color spots and that the altered chromatid segregation pattern of the mutant causes asymmetric cell division to confer the piebald phenotype.
Drury, J. P.; Grether, G. F.
2014-01-01
Traits that mediate intraspecific social interactions may overlap in closely related sympatric species, resulting in costly between-species interactions. Such interactions have principally interested investigators studying the evolution of reproductive isolation via reproductive character displacement (RCD) or reinforcement, yet in addition to reproductive interference, interspecific trait overlap can lead to costly between-species aggression. Previous research on rubyspot damselflies (Hetaerina spp.) demonstrated that sympatric shifts in male wing colour patterns and competitor recognition reduce interspecific aggression, supporting the hypothesis that agonistic character displacement (ACD) drove trait shifts. However, a recent theoretical model shows that RCD overshadows ACD if the same male trait is used for both female mate recognition and male competitor recognition. To determine whether female mate recognition is based on male wing coloration in Hetaerina, we conducted a phenotype manipulation experiment. Compared to control males, male H. americana with wings manipulated to resemble a sympatric congener (H. titia) suffered no reduction in mating success. Thus, female mate recognition is not based on species differences in male wing coloration. Experimental males did, however, experience higher interspecific fighting rates and reduced survival compared to controls. These results greatly strengthen the case for ACD and highlight the mechanistic distinction between ACD and RCD. PMID:25339724
Alightment of Spotted Wing Drosophila (Diptera: Drosophilidae) on Odorless Disks Varying in Color.
Kirkpatrick, D M; McGhee, P S; Hermann, S L; Gut, L J; Miller, J R
2016-02-01
Methods for trapping spotted wing drosophila, Drosophila suzukii (Matsmura) (Diptera: Drosophilidae), have not yet been optimized for detecting this devastating pest of soft-skinned fruits. Here, we report outcomes of choice and no-choice laboratory bioassays quantifying the rates of spotted wing drosophila alightment on 5-cm-diameter sticky disks of various colors, but no fruit odors. Red, purple, and black disks captured the most spotted wing drosophila when presented against a white background. Male and female spotted wing drosophila responded identically in these tests. Significantly more D. suzukii were captured on the red and yellow disks than those presenting the corresponding grayscale for that color, proving that D. suzukii perceives colors and not just the level of target brightness. Fluorescent red is the best candidate for trap color, while clear and white are the least desirable. However, when the background was switched to black, all nonfluorescent colors were equally acceptable to spotted wing drosophila, suggesting that background must be specified when reporting spotted wing drosophila color preference. Additional spotted wing drosophila research is justified on the effects of target color against natural backgrounds. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America.
Preserving and vouchering butterflies and moths for large-scale museum-based molecular research
Epstein, Samantha W.; Mitter, Kim; Hamilton, Chris A.; Plotkin, David; Mitter, Charles
2016-01-01
Butterflies and moths (Lepidoptera) comprise significant portions of the world’s natural history collections, but a standardized tissue preservation protocol for molecular research is largely lacking. Lepidoptera have traditionally been spread on mounting boards to display wing patterns and colors, which are often important for species identification. Many molecular phylogenetic studies have used legs from pinned specimens as the primary source for DNA in order to preserve a morphological voucher, but the amount of available tissue is often limited. Preserving an entire specimen in a cryogenic freezer is ideal for DNA preservation, but without an easily accessible voucher it can make specimen identification, verification, and morphological work difficult. Here we present a procedure that creates accessible and easily visualized “wing vouchers” of individual Lepidoptera specimens, and preserves the remainder of the insect in a cryogenic freezer for molecular research. Wings are preserved in protective holders so that both dorsal and ventral patterns and colors can be easily viewed without further damage. Our wing vouchering system has been implemented at the University of Maryland (AToL Lep Collection) and the University of Florida (Florida Museum of Natural History, McGuire Center of Lepidoptera and Biodiversity), which are among two of the largest Lepidoptera molecular collections in the world. PMID:27366654
Allen, Cerisse E; Beldade, Patrícia; Zwaan, Bas J; Brakefield, Paul M
2008-03-26
There is spectacular morphological diversity in nature but lineages typically display a limited range of phenotypes. Because developmental processes generate the phenotypic variation that fuels natural selection, they are a likely source of evolutionary biases, facilitating some changes and limiting others. Although shifts in developmental regulation are associated with morphological differences between taxa, it is unclear how underlying mechanisms affect the rate and direction of evolutionary change within populations under selection. Here we focus on two ecologically relevant features of butterfly wing color patterns, eyespot size and color composition, which are similarly and strongly correlated across the serially repeated eyespots. Though these two characters show similar patterns of standing variation and covariation within a population, they differ in key features of their underlying development. We targeted pairs of eyespots with artificial selection for coordinated (concerted selection) versus independent (antagonistic selection) change in their color composition and size and compared evolutionary responses of the two color pattern characters. The two characters respond to selection in strikingly different ways despite initially similar patterns of variation in all directions present in the starting population. Size (determined by local properties of a diffusing inductive signal) evolves flexibly in all selected directions. However, color composition (determined by a tissue-level response to the signal concentration gradient) evolves only in the direction of coordinated change. There was no independent evolutionary change in the color composition of two eyespots in response to antagonistic selection. Moreover, these differences in the directions of short-term evolutionary change in eyespot size and color composition within a single species are consistent with the observed wing pattern diversity in the genus. Both characters respond rapidly to selection for coordinated change, but there are striking differences in their response to selection for antagonistic, independent change across eyespots. While many additional factors may contribute to both short- and long-term evolutionary response, we argue that the compartmentalization of developmental processes can influence the diversification of serial repeats such as butterfly eyespots, even under strong selection.
Iwata, Masaki; Otaki, Joji M
2016-01-01
Developmental studies on butterfly wing color patterns often focus on eyespots. A typical eyespot (such as that of Bicyclus anynana) has a few concentric rings of dark and light colors and a white spot (called a focus) at the center. The prospective eyespot center during the early pupal stage is known to act as an organizing center. It has often been assumed, according to gradient models for positional information, that a white spot in adult wings corresponds to an organizing center and that the size of the white spot indicates how active that organizing center was. However, there is no supporting evidence for these assumptions. To evaluate the feasibility of these assumptions in nymphalid butterflies, we studied the unique color patterns of Calisto tasajera (Nymphalidae, Satyrinae), which have not been analyzed before in the literature. In the anterior forewing, one white spot was located at the center of an eyespot, but another white spot associated with either no or only a small eyespot was present in the adjacent compartment. The anterior hindwing contained two adjacent white spots not associated with eyespots, one of which showed a sparse pattern. The posterior hindwing contained two adjacent pear-shaped eyespots, and the white spots were located at the proximal side or even outside the eyespot bodies. The successive white spots within a single compartment along the midline in the posterior hindwing showed a possible trajectory of a positional determination process for the white spots. Several cases of focus-less eyespots in other nymphalid butterflies were also presented. These results argue for the uncoupling of white spots from eyespot bodies, suggesting that an eyespot organizing center does not necessarily differentiate into a white spot and that a prospective white spot does not necessarily signify organizing activity for an eyespot. Incorporation of these results in future models for butterfly wing color pattern formation is encouraged.
Comparative population genetics of a mimicry locus among hybridizing Heliconius butterfly species.
Chamberlain, N L; Hill, R I; Baxter, S W; Jiggins, C D; Kronforst, M R
2011-09-01
The comimetic Heliconius butterfly species pair, H. erato and H. melpomene, appear to use a conserved Mendelian switch locus to generate their matching red wing patterns. Here we investigate whether H. cydno and H. pachinus, species closely related to H. melpomene, use this same switch locus to generate their highly divergent red and brown color pattern elements. Using an F2 intercross between H. cydno and H. pachinus, we first map the genomic positions of two novel red/brown wing pattern elements; the G locus, which controls the presence of red vs brown at the base of the ventral wings, and the Br locus, which controls the presence vs absence of a brown oval pattern on the ventral hind wing. The results reveal that the G locus is tightly linked to markers in the genomic interval that controls red wing pattern elements of H. erato and H. melpomene. Br is on the same linkage group but approximately 26 cM away. Next, we analyze fine-scale patterns of genetic differentiation and linkage disequilibrium throughout the G locus candidate interval in H. cydno, H. pachinus and H. melpomene, and find evidence for elevated differentiation between H. cydno and H. pachinus, but no localized signature of association. Overall, these results indicate that the G locus maps to the same interval as the locus controlling red patterning in H. melpomene and H. erato. This, in turn, suggests that the genes controlling red pattern elements may be homologous across Heliconius, supporting the hypothesis that Heliconius butterflies use a limited suite of conserved genetic switch loci to generate both convergent and divergent wing patterns.
Zhang, Sichao; Chen, Yifang
2015-01-01
The bright and iridescent blue color from Morpho butterfly wings has attracted worldwide attentions to explore its mysterious nature for long time. Although the physics of structural color by the nanophotonic structures built on the wing scales has been well established, replications of the wing structure by standard top-down lithography still remains a challenge. This paper reports a technical breakthrough to mimic the blue color of Morpho butterfly wings, by developing a novel nanofabrication process, based on electron beam lithography combined with alternate PMMA/LOR development/dissolution, for photonic structures with aligned lamellae multilayers in colorless polymers. The relationship between the coloration and geometric dimensions as well as shapes is systematically analyzed by solving Maxwell’s Equations with a finite domain time difference simulator. Careful characterization of the mimicked blue by spectral measurements under both normal and oblique angles are carried out. Structural color in blue reflected by the fabricated wing scales, is demonstrated and further extended to green as an application exercise of the new technique. The effects of the regularity in the replicas on coloration are analyzed. In principle, this approach establishes a starting point for mimicking structural colors beyond the blue in Morpho butterfly wings. PMID:26577813
Zhang, Sichao; Chen, Yifang
2015-11-18
The bright and iridescent blue color from Morpho butterfly wings has attracted worldwide attentions to explore its mysterious nature for long time. Although the physics of structural color by the nanophotonic structures built on the wing scales has been well established, replications of the wing structure by standard top-down lithography still remains a challenge. This paper reports a technical breakthrough to mimic the blue color of Morpho butterfly wings, by developing a novel nanofabrication process, based on electron beam lithography combined with alternate PMMA/LOR development/dissolution, for photonic structures with aligned lamellae multilayers in colorless polymers. The relationship between the coloration and geometric dimensions as well as shapes is systematically analyzed by solving Maxwell's Equations with a finite domain time difference simulator. Careful characterization of the mimicked blue by spectral measurements under both normal and oblique angles are carried out. Structural color in blue reflected by the fabricated wing scales, is demonstrated and further extended to green as an application exercise of the new technique. The effects of the regularity in the replicas on coloration are analyzed. In principle, this approach establishes a starting point for mimicking structural colors beyond the blue in Morpho butterfly wings.
NASA Astrophysics Data System (ADS)
Zhang, Sichao; Chen, Yifang
2015-11-01
The bright and iridescent blue color from Morpho butterfly wings has attracted worldwide attentions to explore its mysterious nature for long time. Although the physics of structural color by the nanophotonic structures built on the wing scales has been well established, replications of the wing structure by standard top-down lithography still remains a challenge. This paper reports a technical breakthrough to mimic the blue color of Morpho butterfly wings, by developing a novel nanofabrication process, based on electron beam lithography combined with alternate PMMA/LOR development/dissolution, for photonic structures with aligned lamellae multilayers in colorless polymers. The relationship between the coloration and geometric dimensions as well as shapes is systematically analyzed by solving Maxwell’s Equations with a finite domain time difference simulator. Careful characterization of the mimicked blue by spectral measurements under both normal and oblique angles are carried out. Structural color in blue reflected by the fabricated wing scales, is demonstrated and further extended to green as an application exercise of the new technique. The effects of the regularity in the replicas on coloration are analyzed. In principle, this approach establishes a starting point for mimicking structural colors beyond the blue in Morpho butterfly wings.
Iwata, Masaki; Taira, Wataru; Hiyama, Atsuki; Otaki, Joji M
2015-06-01
The nymphalid groundplan has been proposed to explain diverse butterfly wing color patterns. In this model, each symmetry system is composed of a core element and a pair of paracore elements. The development of this elemental configuration has been explained by the induction model for positional information. However, the diversity of color patterns in other butterfly families in relation to the nymphalid groundplan has not been thoroughly examined. Here, we examined aberrant color pattern phenotypes of a lycaenid butterfly, Zizeeria maha, from mutagenesis and plasticity studies as well as from field surveys. In several mutants, the third and fourth spot arrays were coordinately positioned much closer to the discal spot in comparison to the normal phenotype. In temperature-shock types, the third and fourth array spots were elongated inwardly or outwardly from their normal positions. In field-caught spontaneous mutants, small black spots were located adjacent to normal black spots. Analysis of these aberrant phenotypes indicated that the spots belonging to the third and fourth arrays are synchronously changeable in position and shape around the discal spot. Thus, these arrays constitute paracore elements of the central symmetry system of the lycaenid butterflies, and the discal spot comprises the core element. These aberrant phenotypes can be explained by the black-inducing signals that propagate from the prospective discal spot, as predicted by the induction model. These results suggest the existence of long-range developmental signals that cover a large area of a wing not only in nymphalid butterflies, but also in lycaenid butterflies.
Hassanalian, M; Abdelmoula, H; Ben Ayed, S; Abdelkefi, A
2017-05-01
The thermal impact of the birds' color on their flight performance are investigated. In most of the large migrating birds, the top of their wings is black. Considering this natural phenomenon in the migrating birds, such as albatross, a thermal analysis of the boundary layer of their wings is performed during the year depending on the solar insulation. It is shown that the temperature difference between the bright and dark colored top wing surface is around 10°C. The dark color on the top of the wing increases the temperature of the boundary layer over the wing which consequently reduces the skin drag force over the wing. This reduction in the drag force can be considered as one of the effective factors for long endurance of these migrating birds. This research should lead to improved designs of the drones by applying the inspired colors which can help drones increase their endurance. Copyright © 2017 Elsevier Ltd. All rights reserved.
Study of nano-architecture of the wings of Paris Peacock butterfly
NASA Astrophysics Data System (ADS)
Ghate, Ekata; Bhoraskar, S. V.; Kulkarni, G. R.
Butterflies are one of the most colorful creatures in animal Kingdom. Wings of the male butterfly are brilliantly colored to attract females. Color of the wings plays an important role in camouflage. Study of structural colors in case of insects and butterflies are important for their biomimic and biophotonic applications. Structural color is the color which is produced by physical structures and their interaction with light. Paris Peacock or Papilio paris butterfly belongs to the family Papilionidae. The basis of structural color of this butterfly is investigated in the present study. The upper surface of the wings in this butterfly is covered with blue, green and brown colored scales. Nano-architecture of these scales was investigated with scanning electron microscope (SEM) and environmental scanning electron microscope (ESEM). Photomicrographs were analyzed using image analysis software. Goniometric color or iridescence in blue and green colored scales of this butterfly was observed and studied with the help of gonio spectrophotometer in the visible range. No iridescence was observed in brown colored scales of the butterfly. Hues of the blue and green color were measured with spectrophotometer and were correlated with nano-architecture of the wing. Results of electron microscopy and reflection spectroscopy are used to explain the iridescent nature of blue and green scales. Sinusoidal grating like structures of these scales were prominently seen in the blue scales. It is possible that the structure of these wings can act as a template for the fabrication of sinusoidal gratings using nano-imprint technology.
An experimental study of separated flow on a finite wing
NASA Technical Reports Server (NTRS)
Winkelmann, A. E.
1981-01-01
The flow field associated with the formation of a mushroom shaped trailing edge stall cell on a low-aspect-ratio (AR = 4.0) wing was investigated in a series of low speed wind tunnel tests (Reynolds number based on 15.2 cm chord = 480,000). Flow field surveys of the separation bubble and wake of a partially stalled and fully stalled wing were completed using a hot-wire probe, a split-film probe, and a directional sensitive pressure probe. A new color video display technique was developed to display the flow field survey data. Photographs were obtained of surface oil flow patterns and smoke flow visualization
The Functional Basis of Wing Patterning in Heliconius Butterflies: The Molecules Behind Mimicry
Kronforst, Marcus R.; Papa, Riccardo
2015-01-01
Wing-pattern mimicry in butterflies has provided an important example of adaptation since Charles Darwin and Alfred Russell Wallace proposed evolution by natural selection >150 years ago. The neotropical butterfly genus Heliconius played a central role in the development of mimicry theory and has since been studied extensively in the context of ecology and population biology, behavior, and mimicry genetics. Heliconius species are notable for their diverse color patterns, and previous crossing experiments revealed that much of this variation is controlled by a small number of large-effect, Mendelian switch loci. Recent comparative analyses have shown that the same switch loci control wing-pattern diversity throughout the genus, and a number of these have now been positionally cloned. Using a combination of comparative genetic mapping, association tests, and gene expression analyses, variation in red wing patterning throughout Heliconius has been traced back to the action of the transcription factor optix. Similarly, the signaling ligand WntA has been shown to control variation in melanin patterning across Heliconius and other butterflies. Our understanding of the molecular basis of Heliconius mimicry is now providing important insights into a variety of additional evolutionary phenomena, including the origin of supergenes, the interplay between constraint and evolvability, the genetic basis of convergence, the potential for introgression to facilitate adaptation, the mechanisms of hybrid speciation in animals, and the process of ecological speciation. PMID:25953905
Ge, Dengteng; Wu, Gaoxiang; Yang, Lili; Kim, Hye-Na; Hallwachs, Winnie; Burns, John M; Janzen, Daniel H; Yang, Shu
2017-07-11
Whiteness, although frequently apparent on the wings, legs, antennae, or bodies of many species of moths and butterflies, along with other colors and shades, has often escaped our attention. Here, we investigate the nanostructure and microstructure of white spots on the wings of Carystoides escalantei , a dusk-active and shade-inhabiting Costa Rican rain forest butterfly (Hesperiidae). On both males and females, two types of whiteness occur: angle dependent (dull or bright) and angle independent, which differ in the microstructure, orientation, and associated properties of their scales. Some spots on the male wings are absent from the female wings. Whether the angle-dependent whiteness is bright or dull depends on the observation directions. The angle-dependent scales also show enhanced retro-reflection. We speculate that the biological functions and evolution of Carystoides spot patterns, scale structures, and their varying whiteness are adaptations to butterfly's low light habitat and to airflow experienced on the wing base vs. wing tip.
Stavenga, Doekele G; Leertouwer, Hein L; Wilts, Bodo D
2014-06-15
The coloration of the common butterflies Aglais urticae (small tortoiseshell), Aglais io (peacock) and Vanessa atalanta (red admiral), belonging to the butterfly subfamily Nymphalinae, is due to the species-specific patterning of differently coloured scales on their wings. We investigated the scales' structural and pigmentary properties by applying scanning electron microscopy, (micro)spectrophotometry and imaging scatterometry. The anatomy of the wing scales appears to be basically identical, with an approximately flat lower lamina connected by trabeculae to a highly structured upper lamina, which consists of an array of longitudinal, parallel ridges and transversal crossribs. Isolated scales observed at the abwing (upper) side are blue, yellow, orange, red, brown or black, depending on their pigmentation. The yellow, orange and red scales contain various amounts of 3-OH-kynurenine and ommochrome pigment, black scales contain a high density of melanin, and blue scales have a minor amount of melanin pigment. Observing the scales from their adwing (lower) side always revealed a structural colour, which is blue in the case of blue, red and black scales, but orange for orange scales. The structural colours are created by the lower lamina, which acts as an optical thin film. Its reflectance spectrum, crucially determined by the lamina thickness, appears to be well tuned to the scales' pigmentary spectrum. The colours observed locally on the wing are also due to the degree of scale stacking. Thin films, tuned pigments and combinations of stacked scales together determine the wing coloration of nymphaline butterflies. © 2014. Published by The Company of Biologists Ltd.
Detailed electromagnetic simulation for the structural color of butterfly wings.
Lee, R Todd; Smith, Glenn S
2009-07-20
Many species of butterflies exhibit interesting optical phenomena due to structural color. The physical reason for this color is subwavelength features on the surface of a single scale. The exposed surface of a scale is covered with a ridge structure. The fully three-dimensional, periodic, finite-difference time-domain method is used to create a detailed electromagnetic model of a generic ridge. A novel method for presenting the three-dimensional observed color pattern is developed. Using these tools, the change in color that is a result of varying individual features of the scale is explored. Computational models are developed that are similar to three butterflies: Morpho rhetenor, Troides magellanus, and Ancyluris meliboeus.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghate, Ekata; Kulkarni, G. R.; Bhoraskar, S. V.
2011-10-20
Study of structural colors in case of insects and butterflies is important for their biomimic and biophotonics applications. Structural color is the color which is produced by physical structures and their interaction with light while pigmentary color is produced by absorption of light by pigments. Common Emigrant butterfly is widely distributed in India. It is of moderate size with wing span of about 60-80 mm. The wings are broadly white with yellow or sulphur yellow coloration at places as well as few dark black patches. It belongs to family Pieridae. A study of structural color in case of Common Emigrantmore » butterfly has been carried out in the present work. The characterization of wing color was performed using absorption spectroscopy. Scanning electron microscopic study of the wings of Common Emigrant butterfly showed that three different types of scales are present on the wing surface dorsally. Diffracting structures are present in certain parts of the surfaces of the various scales. Bead like structures are embedded in the intricate structures of the scales. Absorption spectra revealed that a strong absorption peak is seen in the UV-range. Crystalline structure of beads was confirmed by the X-ray diffraction analysis.« less
Chouteau, Mathieu; Whibley, Annabel; Joron, Mathieu; Llaurens, Violaine
2016-01-01
Identifying the genetic basis of adaptive variation is challenging in non-model organisms and quantitative real time PCR. is a useful tool for validating predictions regarding the expression of candidate genes. However, comparing expression levels in different conditions requires rigorous experimental design and statistical analyses. Here, we focused on the neotropical passion-vine butterflies Heliconius, non-model species studied in evolutionary biology for their adaptive variation in wing color patterns involved in mimicry and in the signaling of their toxicity to predators. We aimed at selecting stable reference genes to be used for normalization of gene expression data in RT-qPCR analyses from developing wing discs according to the minimal guidelines described in Minimum Information for publication of Quantitative Real-Time PCR Experiments (MIQE). To design internal RT-qPCR controls, we studied the stability of expression of nine candidate reference genes (actin, annexin, eF1α, FK506BP, PolyABP, PolyUBQ, RpL3, RPS3A, and tubulin) at two developmental stages (prepupal and pupal) using three widely used programs (GeNorm, NormFinder and BestKeeper). Results showed that, despite differences in statistical methods, genes RpL3, eF1α, polyABP, and annexin were stably expressed in wing discs in late larval and pupal stages of Heliconius numata. This combination of genes may be used as a reference for a reliable study of differential expression in wings for instance for genes involved in important phenotypic variation, such as wing color pattern variation. Through this example, we provide general useful technical recommendations as well as relevant statistical strategies for evolutionary biologists aiming to identify candidate-genes involved adaptive variation in non-model organisms. PMID:27271971
Butterfly wing coloration studied with a novel imaging scatterometer
NASA Astrophysics Data System (ADS)
Stavenga, Doekele
2010-03-01
Animal coloration functions for display or camouflage. Notably insects provide numerous examples of a rich variety of the applied optical mechanisms. For instance, many butterflies feature a distinct dichromatism, that is, the wing coloration of the male and the female differ substantially. The male Brimstone, Gonepteryx rhamni, has yellow wings that are strongly UV iridescent, but the female has white wings with low reflectance in the UV and a high reflectance in the visible wavelength range. In the Small White cabbage butterfly, Pieris rapae crucivora, the wing reflectance of the male is low in the UV and high at visible wavelengths, whereas the wing reflectance of the female is higher in the UV and lower in the visible. Pierid butterflies apply nanosized, strongly scattering beads to achieve their bright coloration. The male Pipevine Swallowtail butterfly, Battus philenor, has dorsal wings with scales functioning as thin film gratings that exhibit polarized iridescence; the dorsal wings of the female are matte black. The polarized iridescence probably functions in intraspecific, sexual signaling, as has been demonstrated in Heliconius butterflies. An example of camouflage is the Green Hairstreak butterfly, Callophrys rubi, where photonic crystal domains exist in the ventral wing scales, resulting in a matte green color that well matches the color of plant leaves. The spectral reflection and polarization characteristics of biological tissues can be rapidly and with unprecedented detail assessed with a novel imaging scatterometer-spectrophotometer, built around an elliptical mirror [1]. Examples of butterfly and damselfly wings, bird feathers, and beetle cuticle will be presented. [4pt] [1] D.G. Stavenga, H.L. Leertouwer, P. Pirih, M.F. Wehling, Optics Express 17, 193-202 (2009)
The redder the better: wing color predicts flight performance in monarch butterflies.
Davis, Andrew K; Chi, Jean; Bradley, Catherine; Altizer, Sonia
2012-01-01
The distinctive orange and black wings of monarchs (Danaus plexippus) have long been known to advertise their bitter taste and toxicity to potential predators. Recent work also showed that both the orange and black coloration of this species can vary in response to individual-level and environmental factors. Here we examine the relationship between wing color and flight performance in captive-reared monarchs using a tethered flight mill apparatus to quantify butterfly flight speed, duration and distance. In three different experiments (totaling 121 individuals) we used image analysis to measure body size and four wing traits among newly-emerged butterflies prior to flight trials: wing area, aspect ratio (length/width), melanism, and orange hue. Results showed that monarchs with darker orange (approaching red) wings flew longer distances than those with lighter orange wings in analyses that controlled for sex and other morphometric traits. This finding is consistent with past work showing that among wild monarchs, those sampled during the fall migration are darker in hue (redder) than non-migratory monarchs. Together, these results suggest that pigment deposition onto wing scales during metamorphosis could be linked with traits that influence flight, such as thorax muscle size, energy storage or metabolism. Our results reinforce an association between wing color and flight performance in insects that is suggested by past studies of wing melansim and seasonal polyphenism, and provide an important starting point for work focused on mechanistic links between insect movement and color.
The Redder the Better: Wing Color Predicts Flight Performance in Monarch Butterflies
Davis, Andrew K.; Chi, Jean; Bradley, Catherine; Altizer, Sonia
2012-01-01
The distinctive orange and black wings of monarchs (Danaus plexippus) have long been known to advertise their bitter taste and toxicity to potential predators. Recent work also showed that both the orange and black coloration of this species can vary in response to individual-level and environmental factors. Here we examine the relationship between wing color and flight performance in captive-reared monarchs using a tethered flight mill apparatus to quantify butterfly flight speed, duration and distance. In three different experiments (totaling 121 individuals) we used image analysis to measure body size and four wing traits among newly-emerged butterflies prior to flight trials: wing area, aspect ratio (length/width), melanism, and orange hue. Results showed that monarchs with darker orange (approaching red) wings flew longer distances than those with lighter orange wings in analyses that controlled for sex and other morphometric traits. This finding is consistent with past work showing that among wild monarchs, those sampled during the fall migration are darker in hue (redder) than non-migratory monarchs. Together, these results suggest that pigment deposition onto wing scales during metamorphosis could be linked with traits that influence flight, such as thorax muscle size, energy storage or metabolism. Our results reinforce an association between wing color and flight performance in insects that is suggested by past studies of wing melansim and seasonal polyphenism, and provide an important starting point for work focused on mechanistic links between insect movement and color. PMID:22848463
Water Tunnel Flow Visualization Study Through Poststall of 12 Novel Planform Shapes
NASA Technical Reports Server (NTRS)
Gatlin, Gregory M.; Neuhart, Dan H.
1996-01-01
To determine the flow field characteristics of 12 planform geometries, a flow visualization investigation was conducted in the Langley 16- by 24-Inch Water Tunnel. Concepts studied included flat plate representations of diamond wings, twin bodies, double wings, cutout wing configurations, and serrated forebodies. The off-surface flow patterns were identified by injecting colored dyes from the model surface into the free-stream flow. These dyes generally were injected so that the localized vortical flow patterns were visualized. Photographs were obtained for angles of attack ranging from 10' to 50', and all investigations were conducted at a test section speed of 0.25 ft per sec. Results from the investigation indicate that the formation of strong vortices on highly swept forebodies can improve poststall lift characteristics; however, the asymmetric bursting of these vortices could produce substantial control problems. A wing cutout was found to significantly alter the position of the forebody vortex on the wing by shifting the vortex inboard. Serrated forebodies were found to effectively generate multiple vortices over the configuration. Vortices from 65' swept forebody serrations tended to roll together, while vortices from 40' swept serrations were more effective in generating additional lift caused by their more independent nature.
Kang, Chang-ku; Moon, Jong-yeol; Lee, Sang-im; Jablonski, Piotr G.
2013-01-01
Many moths have wing patterns that resemble bark of trees on which they rest. The wing patterns help moths to become camouflaged and to avoid predation because the moths are able to assume specific body orientations that produce a very good match between the pattern on the bark and the pattern on the wings. Furthermore, after landing on a bark moths are able to perceive stimuli that correlate with their crypticity and are able to re-position their bodies to new more cryptic locations and body orientations. However, the proximate mechanisms, i.e. how a moth finds an appropriate resting position and orientation, are poorly studied. Here, we used a geometrid moth Jankowskia fuscaria to examine i) whether a choice of resting orientation by moths depends on the properties of natural background, and ii) what sensory cues moths use. We studied moths’ behavior on natural (a tree log) and artificial backgrounds, each of which was designed to mimic one of the hypothetical cues that moths may perceive on a tree trunk (visual pattern, directional furrow structure, and curvature). We found that moths mainly used structural cues from the background when choosing their resting position and orientation. Our findings highlight the possibility that moths use information from one type of sensory modality (structure of furrows is probably detected through tactile channel) to achieve crypticity in another sensory modality (visual). This study extends our knowledge of how behavior, sensory systems and morphology of animals interact to produce crypsis. PMID:24205118
Kang, Chang-Ku; Moon, Jong-Yeol; Lee, Sang-Im; Jablonski, Piotr G
2013-01-01
Many moths have wing patterns that resemble bark of trees on which they rest. The wing patterns help moths to become camouflaged and to avoid predation because the moths are able to assume specific body orientations that produce a very good match between the pattern on the bark and the pattern on the wings. Furthermore, after landing on a bark moths are able to perceive stimuli that correlate with their crypticity and are able to re-position their bodies to new more cryptic locations and body orientations. However, the proximate mechanisms, i.e. how a moth finds an appropriate resting position and orientation, are poorly studied. Here, we used a geometrid moth Jankowskia fuscaria to examine i) whether a choice of resting orientation by moths depends on the properties of natural background, and ii) what sensory cues moths use. We studied moths' behavior on natural (a tree log) and artificial backgrounds, each of which was designed to mimic one of the hypothetical cues that moths may perceive on a tree trunk (visual pattern, directional furrow structure, and curvature). We found that moths mainly used structural cues from the background when choosing their resting position and orientation. Our findings highlight the possibility that moths use information from one type of sensory modality (structure of furrows is probably detected through tactile channel) to achieve crypticity in another sensory modality (visual). This study extends our knowledge of how behavior, sensory systems and morphology of animals interact to produce crypsis.
FijiWingsPolarity: An open source toolkit for semi-automated detection of cell polarity.
Dobens, Leonard L; Shipman, Anna; Axelrod, Jeffrey D
2018-01-02
Epithelial cells are defined by apical-basal and planar cell polarity (PCP) signaling, the latter of which establishes an orthogonal plane of polarity in the epithelial sheet. PCP signaling is required for normal cell migration, differentiation, stem cell generation and tissue repair, and defects in PCP have been associated with developmental abnormalities, neuropathologies and cancers. While the molecular mechanism of PCP is incompletely understood, the deepest insights have come from Drosophila, where PCP is manifest in hairs and bristles across the adult cuticle and organization of the ommatidia in the eye. Fly wing cells are marked by actin-rich trichome structures produced at the distal edge of each cell in the developing wing epithelium and in a mature wing the trichomes orient collectively in the distal direction. Genetic screens have identified key PCP signaling pathway components that disrupt trichome orientation, which has been measured manually in a tedious and error prone process. Here we describe a set of image processing and pattern-recognition macros that can quantify trichome arrangements in micrographs and mark these directly by color, arrow or colored arrow to indicate trichome location, length and orientation. Nearest neighbor calculations are made to exploit local differences in orientation to better and more reliably detect and highlight local defects in trichome polarity. We demonstrate the use of these tools on trichomes in adult wing preps and on actin-rich developing trichomes in pupal wing epithelia stained with phalloidin. FijiWingsPolarity is freely available and will be of interest to a broad community of fly geneticists studying the effect of gene function on PCP.
Marcus, Jeffrey M.; Evans, Travis M.
2008-01-01
The color patterns on the wings of butterflies have been an important model system in evolutionary developmental biology. A recent computational model tested genetic regulatory hierarchies hypothesized to underlie the formation of butterfly eyespot foci (Evans and Marcus, 2006). The computational model demonstrated that one proposed hierarchy was incapable of reproducing the known patterns of gene expression associated with eyespot focus determination in wild-type butterflies, but that two slightly modified alternative hierarchies were capable of reproducing all of the known gene expressions patterns. Here we extend the computational models previously implemented in Delphi 2.0 to two mutants derived from the squinting bush brown butterfly (Bicyclus anynana). These two mutants, comet and Cyclops, have aberrantly shaped eyespot foci that are produced by different mechanisms. The comet mutation appears to produce a modified interaction between the wing margin and the eyespot focus that results in a series of comet-shaped eyespot foci. The Cyclops mutation causes the failure of wing vein formation between two adjacent wing-cells and the fusion of two adjacent eyespot foci to form a single large elongated focus in their place. The computational approach to modeling pattern formation in these mutants allows us to make predictions about patterns of gene expression, which are largely unstudied in butterfly mutants. It also suggests a critical experiment that will allow us to distinguish between two hypothesized genetic regulatory hierarchies that may underlie all butterfly eyespot foci. PMID:18586070
AFM imaging of natural optical structures
NASA Astrophysics Data System (ADS)
Dallaeva, Dinara; Tománek, Pavel; Prokopyeva, Elena; Kaspar, Pavel; Grmela, Lubomír.; Škarvada, Pavel
2015-01-01
The colors of some living organisms assosiated with the surface structure. Irridesence butterfly wings is an example of such coloration. Optical effects such as interference, diffraction, polarization are responsible for physical colors appearance. Alongside with amazing beauty this structure represent interest for design of optical devices. Here we report the results of morphology investigation by atomic force microscopy. The difference in surface structure of black and blue wings areas is clearly observed. It explains the angle dependence of the wing blue color, since these micrometer and sub-micrometer quasiperiodical structures could control the light propagation, absorption and reflection.
USDA-ARS?s Scientific Manuscript database
The lady beetle Coleomegilla maculata is a common New World insect that is naturally colored pink to red or orange with black spots on the forewings of the adult stage. Previous laboratory inbreeding resulted in selection for a strain lacking red pigment in the cuticle and eyes. An additional strain...
Marcus, Jeffrey M; Evans, Travis M
2008-09-01
The color patterns on the wings of butterflies have been an important model system in evolutionary developmental biology. A recent computational model tested genetic regulatory hierarchies hypothesized to underlie the formation of butterfly eyespot foci [Evans, T.M., Marcus, J.M., 2006. A simulation study of the genetic regulatory hierarchy for butterfly eyespot focus determination. Evol. Dev. 8, 273-283]. The computational model demonstrated that one proposed hierarchy was incapable of reproducing the known patterns of gene expression associated with eyespot focus determination in wild-type butterflies, but that two slightly modified alternative hierarchies were capable of reproducing all of the known gene expressions patterns. Here we extend the computational models previously implemented in Delphi 2.0 to two mutants derived from the squinting bush brown butterfly (Bicyclus anynana). These two mutants, comet and Cyclops, have aberrantly shaped eyespot foci that are produced by different mechanisms. The comet mutation appears to produce a modified interaction between the wing margin and the eyespot focus that results in a series of comet-shaped eyespot foci. The Cyclops mutation causes the failure of wing vein formation between two adjacent wing-cells and the fusion of two adjacent eyespot foci to form a single large elongated focus in their place. The computational approach to modeling pattern formation in these mutants allows us to make predictions about patterns of gene expression, which are largely unstudied in butterfly mutants. It also suggests a critical experiment that will allow us to distinguish between two hypothesized genetic regulatory hierarchies that may underlie all butterfly eyespot foci.
Biotemplated Morpho Butterfly Wings for Tunable Structurally Colored Photocatalysts.
Rodríguez, Robin E; Agarwal, Sneha P; An, Shun; Kazyak, Eric; Das, Debashree; Shang, Wen; Skye, Rachael; Deng, Tao; Dasgupta, Neil P
2018-02-07
Morpho sulkowskyi butterfly wings contain naturally occurring hierarchical nanostructures that produce structural coloration. The high aspect ratio and surface area of these wings make them attractive nanostructured templates for applications in solar energy and photocatalysis. However, biomimetic approaches to replicate their complex structural features and integrate functional materials into their three-dimensional framework are highly limited in precision and scalability. Herein, a biotemplating approach is presented that precisely replicates Morpho nanostructures by depositing nanocrystalline ZnO coatings onto wings via low-temperature atomic layer deposition (ALD). This study demonstrates the ability to precisely tune the natural structural coloration while also integrating multifunctionality by imparting photocatalytic activity onto fully intact Morpho wings. Optical spectroscopy and finite-difference time-domain numerical modeling demonstrate that ALD ZnO coatings can rationally tune the structural coloration across the visible spectrum. These structurally colored photocatalysts exhibit an optimal coating thickness to maximize photocatalytic activity, which is attributed to trade-offs between light absorption and catalytic quantum yield with increasing coating thickness. These multifunctional photocatalysts present a new approach to integrating solar energy harvesting into visually attractive surfaces that can be integrated into building facades or other macroscopic structures to impart aesthetic appeal.
Hassanalian, M; Ayed, S Ben; Ali, M; Houde, P; Hocut, C; Abdelkefi, A
2018-02-01
The thermal effects of wing color in flight is investigated in four species of birds with respect to their flight routes, migration time, and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these flight routes, a thermal analysis of the birds' wings is performed during their migration. The surrounding fluxes including the ocean flux and the solar irradiance are considered in an energy balance in order to determine the skin temperature of both sides of the wing. Applying the Blasius solution for heated boundary layers, it is shown that the color configuration of these migrating birds, namely black on the top side of the wings and white on the bottom side of the wings ("countershading"), results in a skin drag reduction, if compared to some other configurations, when both day and night are taken into consideration. This drag reduction can be considered as one of the effective factors for long endurance of these migrating birds. This research can provide the evolutionary perspective behind the colorization of these migrating birds. Copyright © 2018 Elsevier Ltd. All rights reserved.
USDA-ARS?s Scientific Manuscript database
A laboratory colony of Coleomegilla maculata (DeGeer), ye, selected for a pigmentation deficiency, was restored to near wild type cuticle coloration by adding crushed heads and wings of the red colored parental strain to the diet. While the wings and other colored portions of the cuticle regained th...
Hyperspectral optical imaging of two different species of lepidoptera
2011-01-01
In this article, we report a hyperspectral optical imaging application for measurement of the reflectance spectra of photonic structures that produce structural colors with high spatial resolution. The measurement of the spectral reflectance function is exemplified in the butterfly wings of two different species of Lepidoptera: the blue iridescence reflected by the nymphalid Morpho didius and the green iridescence of the papilionid Papilio palinurus. Color coordinates from reflectance spectra were calculated taking into account human spectral sensitivity. For each butterfly wing, the observed color is described by a characteristic color map in the chromaticity diagram and spreads over a limited volume in the color space. The results suggest that variability in the reflectance spectra is correlated with different random arrangements in the spatial distribution of the scales that cover the wing membranes. Hyperspectral optical imaging opens new ways for the non-invasive study and classification of different forms of irregularity in structural colors. PMID:21711872
Giraldo, M A; Stavenga, D G
2016-05-01
Butterflies belonging to the nymphalid subfamily, Morphinae, are famous for their brilliant blue wing coloration and iridescence. These striking optical phenomena are commonly explained as to originate from multilayer reflections by the ridges of the wing scales. Because the lower lamina of the scales of related nymphalid butterflies, the Nymphalinae, plays a dominant role in the wing coloration, by acting as a thin film reflector, we investigated single blue scales of three characteristic Morpho species: M. epistrophus, M. helenor and M. cypris. The experimental data obtained by spectrophotometry, scatterometry and scanning electron microscopy demonstrated that also in the Morpho genus the lower lamina of both the cover and ground scales acts as an optical thin film reflector, contributing importantly to the blue structural coloration of the wings. Melanin pigment has a contrast-enhancing function in a sub-class of ground scales.
Bybee, Seth M; Yuan, Furong; Ramstetter, Monica D; Llorente-Bousquets, Jorge; Reed, Robert D; Osorio, Daniel; Briscoe, Adriana D
2012-01-01
Mimetic wing coloration evolves in butterflies in the context of predator confusion. Unless butterfly eyes have adaptations for discriminating mimetic color variation, mimicry also carries a risk of confusion for the butterflies themselves. Heliconius butterfly eyes, which express recently duplicated ultraviolet (UV) opsins, have such an adaptation. To examine bird and butterfly color vision as sources of selection on butterfly coloration, we studied yellow wing pigmentation in the tribe Heliconiini. We confirmed, using reflectance and mass spectrometry, that only Heliconius use 3-hydroxy-DL-kynurenine (3-OHK), which looks yellow to humans but reflects both UV- and long-wavelength light, whereas butterflies in related genera have chemically unknown yellow pigments mostly lacking UV reflectance. Modeling of these color signals reveals that the two UV photoreceptors of Heliconius are better suited to separating 3-OHK from non-3-OHK spectra compared with the photoreceptors of related genera or birds. The co-occurrence of potentially enhanced UV vision and a UV-reflecting yellow wing pigment could allow unpalatable Heliconius private intraspecific communication in the presence of mimics. Our results are the best available evidence for the correlated evolution of a color signal and color vision. They also suggest that predator visual systems are error prone in the context of mimicry. © 2011 by The University of Chicago.
AY 2002-2003 Industry Study: Final Report Strategic Materials
2003-01-01
Morphing Wing Project;[38] 2) an environmentally friendly, allergy-free fiber for vehicle seats patterned after the light reflection capability of the...Amazon butterfly ;[39] and 3) a camouflage net that changes color in response to its environment inspired by observations of the cuttlefish.[40] These...Biotechnology. The application of molecular level nanocircuits and nanomaterials has great potential in many areas. However, it will be
Industrial melanism in British peppered moths has a singular and recent mutational origin.
van't Hof, Arjen E; Edmonds, Nicola; Dalíková, Martina; Marec, Frantisek; Saccheri, Ilik J
2011-05-20
The rapid spread of a novel black form (known as carbonaria) of the peppered moth Biston betularia in 19th-century Britain is a textbook example of how an altered environment may produce morphological adaptation through genetic change. However, the underlying genetic basis of the difference between the wild-type (light-colored) and carbonaria forms has remained unknown. We have genetically mapped the carbonaria morph to a 200-kilobase region orthologous to a segment of silkworm chromosome 17 and show that there is only one core sequence variant associated with the carbonaria morph, carrying a signature of recent strong selection. The carbonaria region coincides with major wing-patterning loci in other lepidopteran systems, suggesting the existence of basal color-patterning regulators in this region.
Habitat variation and wing coloration affect wing shape evolution in dragonflies.
Outomuro, D; Dijkstra, K-D B; Johansson, F
2013-09-01
Habitats are spatially and temporally variable, and organisms must be able to track these changes. One potential mechanism for this is dispersal by flight. Therefore, we would expect flying animals to show adaptations in wing shape related to habitat variation. In this work, we explored variation in wing shape in relation to preferred water body (flowing water or standing water with tolerance for temporary conditions) and landscape (forested to open) using 32 species of dragonflies of the genus Trithemis (80% of the known species). We included a potential source of variation linked to sexual selection: the extent of wing coloration on hindwings. We used geometric morphometric methods for studying wing shape. We also explored the phenotypic correlation of wing shape between the sexes. We found that wing shape showed a phylogenetic structure and therefore also ran phylogenetic independent contrasts. After correcting for the phylogenetic effects, we found (i) no significant effect of water body on wing shape; (ii) male forewings and female hindwings differed with regard to landscape, being progressively broader from forested to open habitats; (iii) hindwings showed a wider base in wings with more coloration, especially in males; and (iv) evidence for phenotypic correlation of wing shape between the sexes across species. Hence, our results suggest that natural and sexual selection are acting partially independently on fore- and hindwings and with differences between the sexes, despite evidence for phenotypic correlation of wing shape between males and females. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.
McCulloch, Kyle J; Yuan, Furong; Zhen, Ying; Aardema, Matthew L; Smith, Gilbert; Llorente-Bousquets, Jorge; Andolfatto, Peter; Briscoe, Adriana D
2017-09-01
Numerous animal lineages have expanded and diversified the opsin-based photoreceptors in their eyes underlying color vision behavior. However, the selective pressures giving rise to new photoreceptors and their spectral tuning remain mostly obscure. Previously, we identified a violet receptor (UV2) that is the result of a UV opsin gene duplication specific to Heliconius butterflies. At the same time the violet receptor evolved, Heliconius evolved UV-yellow coloration on their wings, due to the pigment 3-hydroxykynurenine (3-OHK) and the nanostructure architecture of the scale cells. In order to better understand the selective pressures giving rise to the violet receptor, we characterized opsin expression patterns using immunostaining (14 species) and RNA-Seq (18 species), and reconstructed evolutionary histories of visual traits in five major lineages within Heliconius and one species from the genus Eueides. Opsin expression patterns are hyperdiverse within Heliconius. We identified six unique retinal mosaics and three distinct forms of sexual dimorphism based on ommatidial types within the genus Heliconius. Additionally, phylogenetic analysis revealed independent losses of opsin expression, pseudogenization events, and relaxation of selection on UVRh2 in one lineage. Despite this diversity, the newly evolved violet receptor is retained across most species and sexes surveyed. Discriminability modeling of behaviorally preferred 3-OHK yellow wing coloration suggests that the violet receptor may facilitate Heliconius color vision in the context of conspecific recognition. Our observations give insights into the selective pressures underlying the origins of new visual receptors. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Butterfly wing color: A photonic crystal demonstration
NASA Astrophysics Data System (ADS)
Proietti Zaccaria, Remo
2016-01-01
We have theoretically modeled the optical behavior of a natural occurring photonic crystal, as defined by the geometrical characteristics of the Teinopalpus Imperialis butterfly. In particular, following a genetic algorithm approach, we demonstrate how its wings follow a triclinic crystal geometry with a tetrahedron unit base. By performing both photonic band analysis and transmission/reflection simulations, we are able to explain the characteristic colors emerging by the butterfly wings, thus confirming their crystal form.
Lithographically-generated 3D lamella layers and their structural color
NASA Astrophysics Data System (ADS)
Zhang, Sichao; Chen, Yifang; Lu, Bingrui; Liu, Jianpeng; Shao, Jinhai; Xu, Chen
2016-04-01
Inspired by the structural color from the multilayer nanophotonic structures in Morpho butterfly wing scales, 3D lamellae layers in dielectric polymers (polymethyl methacrylate, PMMA) with n ~ 1.5 were designed and fabricated by standard top-down electron beam lithography with one-step exposure followed by an alternating development/dissolution process of PMMA/LOR (lift-off resist) multilayers. This work offers direct proof of the structural blue/green color via lithographically-replicated PMMA/air multilayers, analogous to those in real Morpho butterfly wings. The success of nanolithography in this work for the 3D lamellae structures in dielectric polymers not only enables us to gain deeper insight into the mysterious blue color of the Morpho butterfly wings, but also breaks through the bottleneck in technical development toward broad applications in gas/liquid sensors, 3D meta-materials, coloring media, and infrared imaging devices, etc.
Butterfly effects: novel functional materials inspired from the wings scales.
Zhang, Wang; Gu, Jiajun; Liu, Qinglei; Su, Huilan; Fan, Tongxiang; Zhang, Di
2014-10-07
Through millions of years of evolutionary selection, nature has created biological materials with various functional properties for survival. Many complex natural architectures, such as shells, bones, and honeycombs, have been studied and imitated in the design and fabrication of materials with enhanced hardness and stiffness. Recently, more and more researchers have started to research the wings of butterflies, mostly because of their dazzling colors. It was found that most of these iridescent colors are caused by periodic photonic structures on the scales that make up the surfaces of these wings. These materials have recently become a focus of multidiscipline research because of their promising applications in the display of structural colors, and in advanced sensors, photonic crystals, and solar cells. This paper review aims to provide a perspective overview of the research inspired by these wing structures in recent years.
USDA-ARS?s Scientific Manuscript database
Studies of foraging ecology and plant-pollinator interactions benefit from a number of bee (Hymenoptera: Apoidea) characteristics including morphometric measurements, natural history and age. Historically, bee age has been estimated using measurements of wing wear and integument color change. Wing w...
2017-01-01
The evolution of wing pattern in Lepidoptera is a popular area of inquiry but few studies have examined microlepidoptera, with fewer still focusing on intraspecific variation. The tineid genus Moerarchis Durrant, 1914 includes two species with high intraspecific variation of wing pattern. A subset of the specimens examined here provide, to my knowledge, the first examples of wing patterns that follow both the ‘alternating wing-margin’ and ‘uniform wing-margin’ models in different regions along the costa. These models can also be evaluated along the dorsum of Moerarchis, where a similar transition between the two models can be seen. Fusion of veins is shown not to effect wing pattern, in agreement with previous inferences that the plesiomorphic location of wing veins constrains the development of colour pattern. The significant correlation between wing length and number of wing pattern elements in Moerarchis australasiella shows that wing size can act as a major determinant of wing pattern complexity. Lastly, some M. australasiella specimens have wing patterns that conform entirely to the ‘uniform wing-margin’ model and contain more than six bands, providing new empirical insight into the century-old question of how wing venation constrains wing patterns with seven or more bands. PMID:28405390
Biomimicry of optical microstructures of Papilio palinurus
NASA Astrophysics Data System (ADS)
Crne, Matija; Sharma, Vivek; Blair, John; Park, Jung Ok; Summers, Christopher J.; Srinivasarao, Mohan
2011-01-01
The brilliant coloration of animals in nature is sometimes based on their structure rather than on pigments. The green colour on the wings of a butterfly Papilio palinurus originates from the hierarchical microstructure of individual wing scales that are tiled on the wing. The hierarchical structure gives rise to two coloured reflections of visible light, blue and yellow which when additively mixed, produce the perception of green colour on the wing scales. We used breath figure templated assembly as the starting point for the structure and, combining it with atomic layer deposition for the multilayers necessary for the production of interference colors, we have faithfully mimicked the structure and the optical effects found on the wing scale of the butterfly Papilio palinurus.
NASA Astrophysics Data System (ADS)
Vigneron, Jean Pol; Simonis, Priscilla; Aiello, Annette; Bay, Annick; Windsor, Donald M.; Colomer, Jean-François; Rassart, Marie
2010-08-01
The butterfly Pierella luna (Nymphalidae) shows an intriguing rainbow iridescence effect: the forewings of the male, when illuminated along the axis from the body to the wing tip, decompose a white light beam as a diffraction grating would do. Violet light, however, emerges along a grazing angle, near the wing surface, while the other colors, from blue to red, exit respectively at angles progressively closer to the direction perpendicular to the wing plane. This sequence is the reverse of the usual decomposition of light by a grating with a periodicity parallel to the wing surface. It is shown that this effect is produced by a macroscopic deformation of the entire scale, which curls in such a way that it forms a “vertical” grating, perpendicular to the wing surface, and functions in transmission instead of reflection.
Coincident disruptive coloration
Cuthill, Innes C.; Székely, Aron
2008-01-01
Even if an animal matches its surroundings perfectly in colour and texture, any mismatch between the spatial phase of its pattern and that of the background, or shadow created by its three-dimensional relief, is potentially revealing. Nevertheless, for camouflage to be fully broken, the shape must be recognizable. Disruptive coloration acts against object recognition by the use of high-contrast internal colour boundaries to break up shape and form. As well as the general outline, characteristic features such as eyes and limbs must also be concealed; this can be achieved by having the colour patterns on different, but adjacent, body parts aligned to match each other (i.e. in phase). Such ‘coincident disruptive coloration’ ensures that there is no phase disjunction where body parts meet, and causes different sections of the body to blend perceptually. We tested this theory using field experiments with predation by wild birds on artificial moth-like targets, whose wings and (edible pastry) bodies had colour patterns that were variously coincident or not. We also carried out an experiment with humans searching for analogous targets on a computer screen. Both experiments show that coincident disruptive coloration is an effective mechanism for concealing an otherwise revealing body form. PMID:18990668
Divergence with gene flow across a speciation continuum of Heliconius butterflies.
Supple, Megan A; Papa, Riccardo; Hines, Heather M; McMillan, W Owen; Counterman, Brian A
2015-09-24
A key to understanding the origins of species is determining the evolutionary processes that drive the patterns of genomic divergence during speciation. New genomic technologies enable the study of high-resolution genomic patterns of divergence across natural speciation continua, where taxa pairs with different levels of reproductive isolation can be used as proxies for different stages of speciation. Empirical studies of these speciation continua can provide valuable insights into how genomes diverge during speciation. We examine variation across a handful of genomic regions in parapatric and allopatric populations of Heliconius butterflies with varying levels of reproductive isolation. Genome sequences were mapped to 2.2-Mb of the H. erato genome, including 1-Mb across the red color pattern locus and multiple regions unlinked to color pattern variation. Phylogenetic analyses reveal a speciation continuum of pairs of hybridizing races and incipient species in the Heliconius erato clade. Comparisons of hybridizing pairs of divergently colored races and incipient species reveal that genomic divergence increases with ecological and reproductive isolation, not only across the locus responsible for adaptive variation in red wing coloration, but also at genomic regions unlinked to color pattern. We observe high levels of divergence between the incipient species H. erato and H. himera, suggesting that divergence may accumulate early in the speciation process. Comparisons of genomic divergence between the incipient species and allopatric races suggest that limited gene flow cannot account for the observed high levels of divergence between the incipient species. Our results provide a reconstruction of the speciation continuum across the H. erato clade and provide insights into the processes that drive genomic divergence during speciation, establishing the H. erato clade as a powerful framework for the study of speciation.
Butterflies regulate wing temperatures using radiative cooling
NASA Astrophysics Data System (ADS)
Tsai, Cheng-Chia; Shi, Norman Nan; Ren, Crystal; Pelaez, Julianne; Bernard, Gary D.; Yu, Nanfang; Pierce, Naomi
2017-09-01
Butterfly wings are live organs embedded with multiple sensory neurons and, in some species, with pheromoneproducing cells. The proper function of butterfly wings demands a suitable temperature range, but the wings can overheat quickly in the sun due to their small thermal capacity. We developed an infrared technique to map butterfly wing temperatures and discovered that despite the wings' diverse visible colors, regions of wings that contain live cells are the coolest, resulting from the thickness of the wings and scale nanostructures. We also demonstrated that butterflies use behavioral traits to prevent overheating of their wings.
Briolat, Emmanuelle Sophie; Zagrobelny, Mika; Olsen, Carl Erik; Blount, Jonathan D; Stevens, Martin
2018-05-16
The distinctive black and red wing pattern of six-spot burnet moths (Zygaena filipendulae, L.) is a classic example of aposematism, advertising their potent cyanide-based defences. While such warning signals provide a qualitatively honest signal of unprofitability, the evidence for quantitative honesty, whereby variation in visual traits could provide accurate estimates of individual toxicity, is more equivocal. Combining measures of cyanogenic glucoside content and wing colour from the perspective of avian predators, we investigate the relationship between coloration and defences in Z. filipendulae, to test signal honesty both within and across populations. There were no significant relationships between mean cyanogenic glucoside concentration and metrics of wing coloration across populations in males, yet in females higher cyanogenic glucoside levels were associated with smaller and lighter red forewing markings. Trends within populations were similarly inconsistent with quantitative honesty, and persistent differences between the sexes were apparent: larger females, carrying a greater total cyanogenic glucoside load, displayed larger but less conspicuous markings than smaller males, according to several colour metrics. The overall high aversiveness of cyanogenic glucosides and fluctuations in colour and toxin levels during an individual's lifetime may contribute to these results, highlighting generally important reasons why signal honesty should not always be expected in aposematic species. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Giraldo, C E; Uribe, S I
2012-12-01
Species identification in the butterfly genus Mechanitis (F.) (Lepidoptera: Nymphalidae) becomes difficult when it is based only on wing color patterns, a common practice in butterfly taxonomy. Difficulties in Mechanitis taxonomy are related to the widespread mimicry and polymorphism among species belonging to this genus. Species recognition and inventories of Mechanitis genus in geographic areas as the Andean region of Colombia are of particular interest and the use of more than one character for taxonomic identification is desirable. In this study, we included morphological, ecological, and mitochondrial DNA data to identify the occurring species in this region. Species of Mechanitis were studied from ecological, morphological, and molecular perspectives considering host plant identification, oviposition behavior, and life cycles under laboratory conditions. Immature morphology, patterns of wing color, and genital structures of adults were also studied. The genetic barcoding region of the cytochrome oxidase I mitochondrial gene was sequenced and used to verify the limits between species previously defined by the other characters and to validate its usefulness for species delimitation in this particular genus. The integrative approach combining independent datasets successfully allowed species identification as compared to the approach based on a single dataset. Three well-differentiated species were found in the studied region, Mechanitis menapis (Hewitson), Mechanitis polymnia (Linnaeus), and Mechanitis lysimnia (Fabricius). New valuable characters that could improve taxonomic identification in this genus are considered.
Results of woodcock wing collections, 1959 to 1962
Martin, F.W.; Geis, A.D.; Stickel, W.H.
1965-01-01
During hunting seasons from 1959 to 1962, age and sex determined from 45,444 wings were used to measure annual productivity of woodcocks (Philohela minor). Age of birds was determined by pattern and color of secondaries and by wear on primaries. Sex was determined by width and length of primaries. Overall age ratios, weighted by kill estimates, were the same each year and indicated no change in annual productivity. Immature sex ratios in the combined kill were nearly even each year, but kill of adult females was much larger than kill of adult males. The difference in sex ratios between immatures and adults thus suggests higher mortality of males than females after the first hunting season. Since woodcocks are promiscuous, an unbalanced adult sex ratio in favor of females probably does not reduce productivity. There are, however, factors affecting reliability of information deduced from wing collections, and further research is necessary to answer questions on differential vulnerability and mortality rates.
Beyond magic traits: Multimodal mating cues in Heliconius butterflies.
Mérot, Claire; Frérot, Brigitte; Leppik, Ene; Joron, Mathieu
2015-11-01
Species coexistence involves the evolution of reproductive barriers opposing gene flow. Heliconius butterflies display colorful patterns affecting mate choice and survival through warning signaling and mimicry. These patterns are called "magic traits" for speciation because divergent natural selection may promote mimicry shifts in pattern whose role as mating cue facilitates reproductive isolation. By contrast, between comimetic species, natural selection promotes pattern convergence. We addressed whether visual convergence interferes with reproductive isolation by testing for sexual isolation between two closely related species with similar patterns, H. timareta thelxinoe and H. melpomene amaryllis. Experiments with models confirmed visual attraction based on wing phenotype, leading to indiscriminate approach. Nevertheless, mate choice experiments showed assortative mating. Monitoring male behavior toward live females revealed asymmetry in male preference, H. melpomene males courting both species equally while H. timareta males strongly preferred conspecifics. Experiments with hybrid males suggested an important genetic component for such asymmetry. Behavioral observations support a key role for short-distance cues in determining male choice in H. timareta. Scents extracts from wings and genitalia revealed interspecific divergence in chemical signatures, and hybrid female scent composition was significantly associated with courtship intensity by H. timareta males, providing candidate chemical mating cues involved in sexual isolation. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Anderson, Christopher N; Grether, Gregory F
2010-02-22
In zones of sympatry between closely related species, species recognition errors in a competitive context can cause character displacement in agonistic signals and competitor recognition functions, just as species recognition errors in a mating context can cause character displacement in mating signals and mate recognition. These two processes are difficult to distinguish because the same traits can serve as both agonistic and mating signals. One solution is to test for sympatric shifts in recognition functions. We studied competitor recognition in Hetaerina damselflies by challenging territory holders with live tethered conspecific and heterospecific intruders. Heterospecific intruders elicited less aggression than conspecific intruders in species pairs with dissimilar wing coloration (H. occisa/H. titia, H. americana/H. titia) but not in species pairs with similar wing coloration (H. occisa/H. cruentata, H. americana/H. cruentata). Natural variation in the area of black wing pigmentation on H. titia intruders correlated negatively with heterospecific aggression. To directly examine the role of wing coloration, we blackened the wings of H. occisa or H. americana intruders and measured responses of conspecific territory holders. This treatment reduced territorial aggression at multiple sites where H. titia is present, but not at allopatric sites. These results provide strong evidence for agonistic character displacement.
Carr, David M; Ellsworth, Ashley A; Fisher, Gregory L; Valeriano, Wescley W; Vasco, Juan P; Guimarães, Paulo S S; de Andrade, Rodrigo R; da Silva, Elizabeth R; Rodrigues, Wagner N
2018-02-05
The iridescent wings of the Chalcopterix rutilans damselfly (Rambur) (Odonata, Polythoridae) are investigated with focused ion beam/scanning electron microscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry. The electron microscopy images reveal a natural photonic crystal as the source of the varying colors. The photonic crystal has a consistent number and thickness (∼195 nm) of the repeat units on the ventral side of the wing, which is consistent with the red color visible from the bottom side of the wing in all regions. The dorsal side of the wing shows strong color variations ranging from red to blue depending on the region. In the electron microscopy images, the dorsal side of the wing exhibits varied number and thicknesses of the repeat units. The repeat unit spacings for the red, yellow/green, and blue regions are approximately 195, 180, and 145 nm, respectively. Three-dimensional analysis of the natural photonic crystals by time-of-flight secondary ion mass spectrometry reveals that changes in the relative levels of Na, K, and eumelanin are responsible for the varying dielectric constant needed to generate the photonic crystal. The photonic crystal also appears to be assembled with a chemical tricomponent layer structure due to the enhancement of the CH 6 N 3 + species at every other interface between the high/low dielectric constant layers.
Fan, J R; Wu, W G; Chen, Z J; Zhu, J; Li, J
2017-03-09
As plasmonic antennas for surface-plasmon-assisted control of optical fields at specific frequencies, metallic nanostructures have recently emerged as crucial optical components for fascinating plasmonic color engineering. Particularly, plasmonic resonant nanocavities can concentrate lightwave energy to strongly enhance light-matter interactions, making them ideal candidates as optical elements for fine-tuning color displays. Inspired by the color mixing effect found on butterfly wings, a new type of plasmonic, multiresonant, narrow-band (the minimum is about 45 nm), high-reflectance (the maximum is about 95%), and dynamic color-tuning reflector is developed. This is achieved from periodic patterns of plasmonic resonant nanocavities in free-standing capped-pillar nanostructure arrays. Such cavity-coupling structures exhibit multiple narrow-band selective and continuously tunable reflections via plasmon standing-wave resonances. Consequently, they can produce a variety of dark-field vibrant reflective colors with good quality, strong color signal and fine tonal variation at the optical diffraction limit. This proposed multicolor scheme provides an elegant strategy for realizing personalized and customized applications in ultracompact photonic data storage and steganography, colorimetric sensing, 3D holograms and other plasmon-assisted photonic devices.
Briscoe, Adriana D.; Bybee, Seth M.; Bernard, Gary D.; Yuan, Furong; Sison-Mangus, Marilou P.; Reed, Robert D.; Warren, Andrew D.; Llorente-Bousquets, Jorge; Chiao, Chuan-Chin
2010-01-01
The butterfly Heliconius erato can see from the UV to the red part of the light spectrum with color vision proven from 440 to 640 nm. Its eye is known to contain three visual pigments, rhodopsins, produced by an 11-cis-3-hydroxyretinal chromophore together with long wavelength (LWRh), blue (BRh) and UV (UVRh1) opsins. We now find that H. erato has a second UV opsin mRNA (UVRh2)—a previously undescribed duplication of this gene among Lepidoptera. To investigate its evolutionary origin, we screened eye cDNAs from 14 butterfly species in the subfamily Heliconiinae and found both copies only among Heliconius. Phylogeny-based tests of selection indicate positive selection of UVRh2 following duplication, and some of the positively selected sites correspond to vertebrate visual pigment spectral tuning residues. Epi-microspectrophotometry reveals two UV-absorbing rhodopsins in the H. erato eye with λmax = 355 nm and 398 nm. Along with the additional UV opsin, Heliconius have also evolved 3-hydroxy-DL-kynurenine (3-OHK)-based yellow wing pigments not found in close relatives. Visual models of how butterflies perceive wing color variation indicate this has resulted in an expansion of the number of distinguishable yellow colors on Heliconius wings. Functional diversification of the UV-sensitive visual pigments may help explain why the yellow wing pigments of Heliconius are so colorful in the UV range compared to the yellow pigments of close relatives lacking the UV opsin duplicate. PMID:20133601
Briscoe, Adriana D; Bybee, Seth M; Bernard, Gary D; Yuan, Furong; Sison-Mangus, Marilou P; Reed, Robert D; Warren, Andrew D; Llorente-Bousquets, Jorge; Chiao, Chuan-Chin
2010-02-23
The butterfly Heliconius erato can see from the UV to the red part of the light spectrum with color vision proven from 440 to 640 nm. Its eye is known to contain three visual pigments, rhodopsins, produced by an 11-cis-3-hydroxyretinal chromophore together with long wavelength (LWRh), blue (BRh) and UV (UVRh1) opsins. We now find that H. erato has a second UV opsin mRNA (UVRh2)-a previously undescribed duplication of this gene among Lepidoptera. To investigate its evolutionary origin, we screened eye cDNAs from 14 butterfly species in the subfamily Heliconiinae and found both copies only among Heliconius. Phylogeny-based tests of selection indicate positive selection of UVRh2 following duplication, and some of the positively selected sites correspond to vertebrate visual pigment spectral tuning residues. Epi-microspectrophotometry reveals two UV-absorbing rhodopsins in the H. erato eye with lambda(max) = 355 nm and 398 nm. Along with the additional UV opsin, Heliconius have also evolved 3-hydroxy-DL-kynurenine (3-OHK)-based yellow wing pigments not found in close relatives. Visual models of how butterflies perceive wing color variation indicate this has resulted in an expansion of the number of distinguishable yellow colors on Heliconius wings. Functional diversification of the UV-sensitive visual pigments may help explain why the yellow wing pigments of Heliconius are so colorful in the UV range compared to the yellow pigments of close relatives lacking the UV opsin duplicate.
Özsu, Nesibe; Monteiro, Antónia
2017-10-16
One hypothesis surrounding the origin of novel traits is that they originate from the co-option of pre-existing genes or larger gene regulatory networks into novel developmental contexts. Insights into a trait's evolutionary origins can, thus, be gained via identification of the genes underlying trait development, and exploring whether those genes also function in other developmental contexts. Here we investigate the set of genes associated with the development of eyespot color patterns, a trait that originated once within the Nymphalid family of butterflies. Although several genes associated with eyespot development have been identified, the eyespot gene regulatory network remains largely unknown. In this study, next-generation sequencing and transcriptome analyses were used to identify a large set of genes associated with eyespot development of Bicyclus anynana butterflies, at 3-6 h after pupation, prior to the differentiation of the color rings. Eyespot-associated genes were identified by comparing the transcriptomes of homologous micro-dissected wing tissues that either develop or do not develop eyespots in wild-type and a mutant line of butterflies, Spotty, with extra eyespots. Overall, 186 genes were significantly up and down-regulated in wing tissues that develop eyespots compared to wing tissues that do not. Many of the differentially expressed genes have yet to be annotated. New signaling pathways, including the Toll, Fibroblast Growth Factor (FGF), extracellular signal-regulated kinase (ERK) and/or Jun N-terminal kinase (JNK) signaling pathways are associated for the first time with eyespot development. In addition, several genes involved in wound healing and calcium signaling were also found to be associated with eyespots. Overall, this study provides the identity of many new genes and signaling pathways associated with eyespots, and suggests that the ancient wound healing gene regulatory network may have been co-opted to cells at the center of the pattern to aid in eyespot origins. New transcription factors that may be providing different identities to distinct wing sectors, and genes with sexually dimorphic expression in the eyespots were also identified.
Bioinspired Omnidirectional Self-Stable Reflectors with Multiscale Hierarchical Structures.
Han, Zhiwu; Mu, Zhengzhi; Li, Bo; Feng, Xiaoming; Wang, Ze; Zhang, Junqiu; Niu, Shichao; Ren, Luquan
2017-08-30
Structured surfaces, demonstrating various wondrous physicochemical performances, are ubiquitous phenomena in nature. Butterfly wings with impressive structural colors are an interesting example for multiscale hierarchical structures (MHSs). However, most natural structural colors are relatively unstable and highly sensitive to incident angles, which limit their potential practical applications to a certain extent. Here, we reported a bioinspired color reflector with omnidirectional reflective self-stable (ORS) properties, which is inspired by the wing scales of Papilio palinurus butterfly. Through experimental exploration and theoretical analysis, it was found that the vivid colors of such butterfly wings are structure-based and possess novel ORS properties, which attributes to the multiple optical actions between light and the complex structures coupling the inverse opal-like structures (IOSs) and stacked lamellar ridges (SLRs). On the basis of this, we designed and successfully fabricated the SiO 2 -based bioinspired color reflectors (BCRs) through a facile and effective biotemplate method. It was confirmed that the MHSs in biotemplate are inherited by the obtained SiO 2 -based BCRs. More importantly, the SiO 2 -based BCRs also demonstrated the similar ORS properties in a wide wavelength range. We forcefully anticipate that the reported MHS-based ORS performance discovered in butterfly wing scales here could offer new thoughts for scientists to solve unstable reflection issues in particular optical field. The involved biotemplate fabrication method offers a facile and effective strategy for fabricating functional nanomaterials or bioinspired nanodevices with 3D complex nanostructures, such as structured optical devices, displays, and optoelectronic equipment.
Bae, Won-Gyu; Kim, Hong Nam; Kim, Doogon; Park, Suk-Hee; Jeong, Hoon Eui; Suh, Kahp-Yang
2014-02-01
Multiscale, hierarchically patterned surfaces, such as lotus leaves, butterfly wings, adhesion pads of gecko lizards are abundantly found in nature, where microstructures are usually used to strengthen the mechanical stability while nanostructures offer the main functionality, i.e., wettability, structural color, or dry adhesion. To emulate such hierarchical structures in nature, multiscale, multilevel patterning has been extensively utilized for the last few decades towards various applications ranging from wetting control, structural colors, to tissue scaffolds. In this review, we highlight recent advances in scalable multiscale patterning to bring about improved functions that can even surpass those found in nature, with particular focus on the analogy between natural and synthetic architectures in terms of the role of different length scales. This review is organized into four sections. First, the role and importance of multiscale, hierarchical structures is described with four representative examples. Second, recent achievements in multiscale patterning are introduced with their strengths and weaknesses. Third, four application areas of wetting control, dry adhesives, selectively filtrating membranes, and multiscale tissue scaffolds are overviewed by stressing out how and why multiscale structures need to be incorporated to carry out their performances. Finally, we present future directions and challenges for scalable, multiscale patterned surfaces. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Variation in wing pattern and palatability in a female-limited polymorphic mimicry system
Long, Elizabeth C; Hahn, Thomas P; Shapiro, Arthur M
2014-01-01
Checkerspot butterflies in the genera Euphydryas and Chlosyne exhibit phenotypic polymorphisms along a well-defined latitudinal and elevational gradient in California. The patterns of phenotypic variation in Euphydryas chalcedona, Chlosyne palla, and Chlosyne hoffmanni suggest a mimetic relationship; in addition, the specific patterns of variation in C. palla suggest a female-limited polymorphic mimicry system (FPM). However, the existence of polymorphic models runs counter to predictions of mimicry theory. Palatability trials were undertaken to assess whether or not the different color morphs of each species were distasteful or toxic to a generalized avian predator, the European starling (Sturnus vulgaris). Results indicate that the black morph of E. chalcedona is distasteful, but not toxic, to predators, while the red morph is palatable. C . hoffmanni and both color morphs of C. palla are palatable to predators. Predators that learn to reject black E. chalcedona also reject black C. palla, suggesting that the latter is a FPM of the former. C. hoffmanni does not appear to be involved in this mimetic relationship. PMID:25512850
Mysterious coloring: structural origin of color mixing for two breeds of Papilio butterflies.
Diao, Ying-Ying; Liu, Xiang-Yang
2011-05-09
The structural origin of the coloration mechanisms and related extraordinary optical properties of the wing scales of two breeds of Papilio butterflies, namely, Papilio ulysses and Papilio blumei, are explored. The precise ordered biophotonic nanostructures of the wing scales are characterized by scanning electron microscopy (SEM). Despite their structural similarities, the two breeds of Papilio butterflies do not exhibit any analogy in their optical performances. When illuminated with UV-Vis light, P. ulysses gives rise to two reflection peaks: one is from concavities, and the other is from ridges. These two spectral peaks shift their positions under different illumination angles (normal and 45° incident light). In contrast, the spectra for the green scales of P. blumei give one broad reflection peak, and the peak remains the same under normal and 45° incident light. The optical microscopy images indicate that the cap-shaped concavities on P. blumei's wing scales generate an abnormal bicolor reflection with a strong polarization effect. Both of these two breeds of butterflies take advantage of color mixing strategy: the blue color of P. ulysses is mixed by the colors reflected from concavities and ridges; the green color of P. blumei is produced by the biocolor reflection from concavities. The differences of their coloration mixing mechanisms and optical performances are due to the variations of their nanostructures. The investigation of the color mixing mechanisms of these biologically photonic nanostructures may offer a convenient way for fabricating optical devices based on biomimicry. © 2011 Optical Society of America
NASA Astrophysics Data System (ADS)
Seino, M.; Kakazu, Y.
The vein and cell patterns for the fore and hind wing of Lepidoptera, Hemiptera, Orthoptera and Odonata are analyzed and discussed. For vein patterns of them, the fractal properties are shown and the inequality between four orders is obtained. The nature of wings observed by mass distributions for fractal dimensions of the vein pattern is presented.
Gulmez, M; Oral, N; Vatansever, L
2006-08-01
In an attempt to improve the bacteriological quality and refrigerated shelf life of broiler meat, 10-min surface wash treatments with sterile distilled water (DW), 8% (wt/vol) water extract of sumac (Rhus coriaria L.) fruits (WES), and 2% (vol/vol) lactic acid (LA) were compared by using a broiler wing model. The aerobic plate counts (log10 cfu/g) of psychrotrophs, mesophilic aerobes, Enterobacteriaceae, coliforms and presumptive fecal coliforms on the samples were determined. Immediately after a 10-min decontaminaton, the mean count of all the bacterial groups was determined to be 3.9, 2.6, and 1.7 (log10 cfu/g) for DW, WES, and LA, respectively. Because the postdecontamination population level of psychrotrophs, mesophiles, and Enterobacteriaceae were low in the LA-treated group compared to the WES group, an equity between the 2 groups in the point of view of the 3 bacterial groups existed at d 10 of cold storage (3 +/- 1 degrees C). Shelf life was 7 and 14 d for wings treated with DW and WES, respectively, whereas the LA-treated wings did not spoil after 14 d of cold storage (3 +/- 1 degrees C). Nevertheless, an undesirable pale color and an acidulous odor occurred in the LA-treated wings. In contrast, a good color appeared on the WES-treated wings, which was also superior to the color of the DW-treated wings. Such advantages of WES may be important for poultry processors and for consumers. However, the immediate decontamination and refrigerated shelf life extension potential of WES should be intensively studied in antimicrobial interventions in poultry processing plants.
Distal-less regulates eyespot patterns and melanization in Bicyclus butterflies.
Monteiro, Antónia; Chen, Bin; Ramos, Diane M; Oliver, Jeffrey C; Tong, Xiaoling; Guo, Min; Wang, Wen-Kai; Fazzino, Lisa; Kamal, Firdous
2013-07-01
Butterfly eyespots represent novel complex traits that display substantial diversity in number and size within and across species. Correlative gene expression studies have implicated a large suite of transcription factors, including Distal-less (Dll), Engrailed (En), and Spalt (Sal), in eyespot development in butterflies, but direct evidence testing the function of any of these proteins is still missing. Here we show that the characteristic two-eyespot pattern of wildtype Bicyclus anynana forewings is correlated with dynamic progression of Dll, En, and Sal expression in larval wings from four spots to two spots, whereas no such decline in gene expression ensues in a four-eyespot mutant. We then conduct transgenic experiments testing whether over-expression of any of these genes in a wild-type genetic background is sufficient to induce eyespot differentiation in these pre-patterned wing compartments. We also produce a Dll-RNAi transgenic line to test how Dll down-regulation affects eyespot development. Finally we test how ectopic expression of these genes during the pupal stages of development alters adults color patters. We show that over-expressing Dll in larvae is sufficient to induce the differentiation of additional eyespots and increase the size of eyespots, whereas down-regulating Dll leads to a decrease in eyespot size. Furthermore, ectopic expression of Dll in the early pupal wing led to the appearance of ectopic patches of black scales. We conclude that Dll is a positive regulator of focal differentiation and eyespot signaling and that this gene is also a possible selector gene for scale melanization in butterflies. Copyright © 2013 Wiley Periodicals, Inc.
Coloration mechanisms and phylogeny of Morpho butterflies.
Giraldo, M A; Yoshioka, S; Liu, C; Stavenga, D G
2016-12-15
Morpho butterflies are universally admired for their iridescent blue coloration, which is due to nanostructured wing scales. We performed a comparative study on the coloration of 16 Morpho species, investigating the morphological, spectral and spatial scattering properties of the differently organized wing scales. In numerous previous studies, the bright blue Morpho coloration has been fully attributed to the multi-layered ridges of the cover scales' upper laminae, but we found that the lower laminae of the cover and ground scales play an important additional role, by acting as optical thin film reflectors. We conclude that Morpho coloration is a subtle combination of overlapping pigmented and/or unpigmented scales, multilayer systems, optical thin films and sometimes undulated scale surfaces. Based on the scales' architecture and their organization, five main groups can be distinguished within the genus Morpho, largely agreeing with the accepted phylogeny. © 2016. Published by The Company of Biologists Ltd.
Aymone, A C B; Valente, V L S; de Araújo, A M
2013-09-01
Usually the literature on Heliconius show three types of scales, classified based on the correlation between color and ultrastructure: type I - white and yellow, type II - black, and type III - orange and red. The ultrastructure of the scales located at the silvery/brownish surfaces of males/females is for the first time described in this paper. Besides, we describe the ontogeny of pigmentation, the scale morphogenesis and the maturation timing of scales fated to different colors in Heliconius erato phyllis. The silvery/brownish surfaces showed ultrastructurally similar scales to the type I, II and III. The ontogeny of pigmentation follows the sequence red, black, silvery/brownish and yellow. The maturation of yellow-fated scales, however, occurred simultaneously with the red-fated scales, before the pigmentation becomes visible. In spite of the scales at the silvery/brownish surfaces being ultrastructurally similar to the yellow, red and black scales, they mature after them; this suggests that the maturation timing does not show a relationship with the scale ultrastructure, with the deposition timing of the yellow pigment. The analysis of H. erato phyllis scale morphogenesis, as well as the scales ultrastructure and maturation timing, provided new findings into the developmental architecture of color pattern in Heliconius. Copyright © 2013 Elsevier Ltd. All rights reserved.
Genomic Sequence around Butterfly Wing Development Genes: Annotation and Comparative Analysis
Conceição, Inês C.; Long, Anthony D.; Gruber, Jonathan D.; Beldade, Patrícia
2011-01-01
Background Analysis of genomic sequence allows characterization of genome content and organization, and access beyond gene-coding regions for identification of functional elements. BAC libraries, where relatively large genomic regions are made readily available, are especially useful for species without a fully sequenced genome and can increase genomic coverage of phylogenetic and biological diversity. For example, no butterfly genome is yet available despite the unique genetic and biological properties of this group, such as diversified wing color patterns. The evolution and development of these patterns is being studied in a few target species, including Bicyclus anynana, where a whole-genome BAC library allows targeted access to large genomic regions. Methodology/Principal Findings We characterize ∼1.3 Mb of genomic sequence around 11 selected genes expressed in B. anynana developing wings. Extensive manual curation of in silico predictions, also making use of a large dataset of expressed genes for this species, identified repetitive elements and protein coding sequence, and highlighted an expansion of Alcohol dehydrogenase genes. Comparative analysis with orthologous regions of the lepidopteran reference genome allowed assessment of conservation of fine-scale synteny (with detection of new inversions and translocations) and of DNA sequence (with detection of high levels of conservation of non-coding regions around some, but not all, developmental genes). Conclusions The general properties and organization of the available B. anynana genomic sequence are similar to the lepidopteran reference, despite the more than 140 MY divergence. Our results lay the groundwork for further studies of new interesting findings in relation to both coding and non-coding sequence: 1) the Alcohol dehydrogenase expansion with higher similarity between the five tandemly-repeated B. anynana paralogs than with the corresponding B. mori orthologs, and 2) the high conservation of non-coding sequence around the genes wingless and Ecdysone receptor, both involved in multiple developmental processes including wing pattern formation. PMID:21909358
2014-06-01
B. Beetle wing colors Whereas most insect wings are rather thin and flexible chitinous structures, in beetles this holds for only one wing pair...symbols). The black line is the dispersion curve for insect chitin . D. Insect photoreceptors Insect vision starts with the absorption of light by the...BD (2012) Sexual dichromatism of the damselfly Calopteryx japonica caused by a melanin- chitin multilayer in the male wing veins. PLoS ONE 7: e49743
Rimini, Simone; Petracci, Massimiliano; Smith, Douglas P
2014-08-01
Poultry meat contains large quantities of polyunsaturated fatty acids, which lead to oxidative deterioration. Plant essential oils (EO) and natural compounds, with antioxidant properties, may be used to alleviate this problem. Two replications were conducted to evaluate the effects of a mixture (1:1) of thyme and orange oils (EO) on the quality characteristics and the oxidative stability of chicken meat (breast and wing). For each replication, 24 fresh breast fillets and 24 wings were procured from a local grocery store. The EO were added to marinade solution to achieve a final concentration of 0.55% sodium chloride, 0.28% polyphosphate, and 0.05% wt/vol of EO blend. Breasts and wings were split in 2 different groups with homogenous pH and lightness and vacuum tumbled in 2 treatments, a 0.5% EO and a control (CON, no EO). Each group was tested for pH, Commission Internationale d'Eclairage color (lightness, L*; redness, a*; yellowness, b*), moisture content, marinade uptake, purge loss, cook yield, and shear force. Susceptibility to lipid oxidation was determined on fresh and frozen meat by TBA reactive substance analysis (induced oxidation from 0 to 150 min at 37°C). The EO breasts had lower purge loss compared with CON meat. Breast did not show any color, pH, marinade uptake, cooking yield, shear force, or moisture differences due to treatment, although cooked EO breast was slightly less red than CON. The EO wings presented higher a* and b* values after marination and lower purge loss and shear force than CON. No differences were detected on wings for color, pH, marinade uptake, cooking yield, or moisture between EO and CON wings. Both fresh and frozen EO breasts and EO wings were less susceptible to the lipid oxidation during all induced oxidation times compared with CON breasts and wings. In conclusion, EO had a positive effect on broiler breast and wing lipid oxidation without negatively affecting meat quality traits. © Poultry Science Association Inc.
Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter
2016-01-01
Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and the averaged measurements using an integrating sphere are in agreement. PMID:27832120
Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter
2016-01-01
Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and the averaged measurements using an integrating sphere are in agreement.
Jiggins, Chris D; Wallbank, Richard W R; Hanly, Joseph J
2017-02-05
A major challenge is to understand how conserved gene regulatory networks control the wonderful diversity of form that we see among animals and plants. Butterfly wing patterns are an excellent example of this diversity. Butterfly wings form as imaginal discs in the caterpillar and are constructed by a gene regulatory network, much of which is conserved across the holometabolous insects. Recent work in Heliconius butterflies takes advantage of genomic approaches and offers insights into how the diversification of wing patterns is overlaid onto this conserved network. WntA is a patterning morphogen that alters spatial information in the wing. Optix is a transcription factor that acts later in development to paint specific wing regions red. Both of these loci fit the paradigm of conserved protein-coding loci with diverse regulatory elements and developmental roles that have taken on novel derived functions in patterning wings. These discoveries offer insights into the 'Nymphalid Ground Plan', which offers a unifying hypothesis for pattern formation across nymphalid butterflies. These loci also represent 'hotspots' for morphological change that have been targeted repeatedly during evolution. Both convergent and divergent evolution of a great diversity of patterns is controlled by complex alleles at just a few genes. We suggest that evolutionary change has become focused on one or a few genetic loci for two reasons. First, pre-existing complex cis-regulatory loci that already interact with potentially relevant transcription factors are more likely to acquire novel functions in wing patterning. Second, the shape of wing regulatory networks may constrain evolutionary change to one or a few loci. Overall, genomic approaches that have identified wing patterning loci in these butterflies offer broad insight into how gene regulatory networks evolve to produce diversity.This article is part of the themed issue 'Evo-devo in the genomics era, and the origins of morphological diversity'. © 2016 The Author(s).
Wallbank, Richard W. R.; Hanly, Joseph J.
2017-01-01
A major challenge is to understand how conserved gene regulatory networks control the wonderful diversity of form that we see among animals and plants. Butterfly wing patterns are an excellent example of this diversity. Butterfly wings form as imaginal discs in the caterpillar and are constructed by a gene regulatory network, much of which is conserved across the holometabolous insects. Recent work in Heliconius butterflies takes advantage of genomic approaches and offers insights into how the diversification of wing patterns is overlaid onto this conserved network. WntA is a patterning morphogen that alters spatial information in the wing. Optix is a transcription factor that acts later in development to paint specific wing regions red. Both of these loci fit the paradigm of conserved protein-coding loci with diverse regulatory elements and developmental roles that have taken on novel derived functions in patterning wings. These discoveries offer insights into the ‘Nymphalid Ground Plan’, which offers a unifying hypothesis for pattern formation across nymphalid butterflies. These loci also represent ‘hotspots’ for morphological change that have been targeted repeatedly during evolution. Both convergent and divergent evolution of a great diversity of patterns is controlled by complex alleles at just a few genes. We suggest that evolutionary change has become focused on one or a few genetic loci for two reasons. First, pre-existing complex cis-regulatory loci that already interact with potentially relevant transcription factors are more likely to acquire novel functions in wing patterning. Second, the shape of wing regulatory networks may constrain evolutionary change to one or a few loci. Overall, genomic approaches that have identified wing patterning loci in these butterflies offer broad insight into how gene regulatory networks evolve to produce diversity. This article is part of the themed issue ‘Evo-devo in the genomics era, and the origins of morphological diversity’. PMID:27994126
Ćurčić, Srećko B; Pantelić, Dejan V; Ćurčić, Božidar P M; Savić-Šević, Svetlana N; Makarov, Slobodan E; Lačković, Vesna B; Labudović-Borović, Milica M; Ćurčić, Nina B; Stojanović, Dejan V
2012-07-01
Apatura ilia (Denis and Schiffermüller, 1775) and A. iris (Linnaeus, 1758) are fascinating butterflies found in the Palaearctic ecozone (excepting the north of Africa). The wings of these insects are covered with a great number of two types of scales positioned like roof tiles. Type I scales are on the surface, while type II scales are situated below them. The structural color of the type I scales is recognized only on the dorsal side of both the fore and hind wings of the males of the aforementioned species. Both types of scales are responsible for pigment color of the wings, but iridescence is observed only in the type I scales. The brilliant structural color is due to a multilayer structure. The features of the scales, their dimensions and fine structure were obtained using scanning electron microscopy. Cross sections of the scales were then analyzed by transmission electron microscopy. The scales of the "normal" and clytie forms of A. ilia have a different nanostructure, but are of the same type. A similar type of structure, but with a different morphology, was also noticed in A. iris. The scales of the analyzed species resemble the scales of tropical Morpho butterflies. Copyright © 2012 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Van Hooijdonk, Eloise; Berthier, Serge; Vigneron, Jean-Pol
2012-10-01
Until now, the existing literature suggests that the color effects on the butterflies wings come from the scales exposed to an outside observer. The particularity of the present work lies in the consideration of both sides of a wing. The male Troïdes magellanus concentrates on its hindwings distinct but complementary optical effects contributing to its exceptional visual attraction: (i) a uniform yellow coloration under daylight, (ii) a bright glint showing bluish or greenish hues under grazing illumination and observation, and (iii) the presence of fluorescent molecules, producing a yellow-green coloration when irradiated by ultraviolet light, embedded in a three-dimensional photonic structure. Our experimental examination reveals a decomposition of the visual aspect in terms of a pigmentary, a structural, and a fluorescent component, as well as a contribution of the scales of the upperside and the underside of the wing on this observation. Our results highlight the role of the scales photonic structure—from both sides of the organ—on this correlation. The investigation was realized by means of spectrophotometric measurements, bidirectional reflectance distribution function mapping, and electron microscopy. Analyzing the scattered light according to the observation direction proved to be crucial in this work.
Nijhout, H Frederik; Cinderella, Margaret; Grunert, Laura W
2014-03-01
The wings of butterflies and moths develop from imaginal disks whose structure is always congruent with the final adult wing. It is therefore possible to map every point on the imaginal disk to a location on the adult wing throughout ontogeny. We studied the growth patterns of the wings of two distantly related species with very different adult wing shapes, Junonia coenia and Manduca sexta. The shape of the wing disks change throughout their growth phase in a species-specific pattern. We measured mitotic densities and mitotic orientation in successive stages of wing development approximately one cell division apart. Cell proliferation was spatially patterned, and the density of mitoses was highly correlated with local growth. Unlike other systems in which the direction of mitoses has been viewed as the primary determinant of directional growth, we found that in these two species the direction of growth was only weakly correlated with the orientation of mitoses. Directional growth appears to be imposed by a constantly changing spatial pattern of cell division coupled with a weak bias in the orientation of cell division. Because growth and cell division in imaginal disk require ecdysone and insulin signaling, the changing spatial pattern of cell division may due to a changing pattern of expression of receptors or downstream elements in the signaling pathways for one or both of these hormones. Evolution of wing shape comes about by changes in the progression of spatial patterns of cell division. © 2014 Wiley Periodicals, Inc.
A wing expressed sequence tag resource for Bicyclus anynana butterflies, an evo-devo model
Beldade, Patrícia; Rudd, Stephen; Gruber, Jonathan D; Long, Anthony D
2006-01-01
Background Butterfly wing color patterns are a key model for integrating evolutionary developmental biology and the study of adaptive morphological evolution. Yet, despite the biological, economical and educational value of butterflies they are still relatively under-represented in terms of available genomic resources. Here, we describe an Expression Sequence Tag (EST) project for Bicyclus anynana that has identified the largest available collection to date of expressed genes for any butterfly. Results By targeting cDNAs from developing wings at the stages when pattern is specified, we biased gene discovery towards genes potentially involved in pattern formation. Assembly of 9,903 ESTs from a subtracted library allowed us to identify 4,251 genes of which 2,461 were annotated based on BLAST analyses against relevant gene collections. Gene prediction software identified 2,202 peptides, of which 215 longer than 100 amino acids had no homology to any known proteins and, thus, potentially represent novel or highly diverged butterfly genes. We combined gene and Single Nucleotide Polymorphism (SNP) identification by constructing cDNA libraries from pools of outbred individuals, and by sequencing clones from the 3' end to maximize alignment depth. Alignments of multi-member contigs allowed us to identify over 14,000 putative SNPs, with 316 genes having at least one high confidence double-hit SNP. We furthermore identified 320 microsatellites in transcribed genes that can potentially be used as genetic markers. Conclusion Our project was designed to combine gene and sequence polymorphism discovery and has generated the largest gene collection available for any butterfly and many potential markers in expressed genes. These resources will be invaluable for exploring the potential of B. anynana in particular, and butterflies in general, as models in ecological, evolutionary, and developmental genetics. PMID:16737530
Artificial selection for structural color on butterfly wings and comparison with natural evolution
Wasik, Bethany R.; Liew, Seng Fatt; Lilien, David A.; Dinwiddie, April J.; Noh, Heeso; Cao, Hui; Monteiro, Antónia
2014-01-01
Brilliant animal colors often are produced from light interacting with intricate nano-morphologies present in biological materials such as butterfly wing scales. Surveys across widely divergent butterfly species have identified multiple mechanisms of structural color production; however, little is known about how these colors evolved. Here, we examine how closely related species and populations of Bicyclus butterflies have evolved violet structural color from brown-pigmented ancestors with UV structural color. We used artificial selection on a laboratory model butterfly, B. anynana, to evolve violet scales from UV brown scales and compared the mechanism of violet color production with that of two other Bicyclus species, Bicyclus sambulos and Bicyclus medontias, which have evolved violet/blue scales independently via natural selection. The UV reflectance peak of B. anynana brown scales shifted to violet over six generations of artificial selection (i.e., in less than 1 y) as the result of an increase in the thickness of the lower lamina in ground scales. Similar scale structures and the same mechanism for producing violet/blue structural colors were found in the other Bicyclus species. This work shows that populations harbor large amounts of standing genetic variation that can lead to rapid evolution of scales’ structural color via slight modifications to the scales’ physical dimensions. PMID:25092295
Artificial selection for structural color on butterfly wings and comparison with natural evolution.
Wasik, Bethany R; Liew, Seng Fatt; Lilien, David A; Dinwiddie, April J; Noh, Heeso; Cao, Hui; Monteiro, Antónia
2014-08-19
Brilliant animal colors often are produced from light interacting with intricate nano-morphologies present in biological materials such as butterfly wing scales. Surveys across widely divergent butterfly species have identified multiple mechanisms of structural color production; however, little is known about how these colors evolved. Here, we examine how closely related species and populations of Bicyclus butterflies have evolved violet structural color from brown-pigmented ancestors with UV structural color. We used artificial selection on a laboratory model butterfly, B. anynana, to evolve violet scales from UV brown scales and compared the mechanism of violet color production with that of two other Bicyclus species, Bicyclus sambulos and Bicyclus medontias, which have evolved violet/blue scales independently via natural selection. The UV reflectance peak of B. anynana brown scales shifted to violet over six generations of artificial selection (i.e., in less than 1 y) as the result of an increase in the thickness of the lower lamina in ground scales. Similar scale structures and the same mechanism for producing violet/blue structural colors were found in the other Bicyclus species. This work shows that populations harbor large amounts of standing genetic variation that can lead to rapid evolution of scales' structural color via slight modifications to the scales' physical dimensions.
2012-01-01
Background Body coloration is an ecologically important trait that is often involved in prey-predator interactions through mimicry and crypsis. Although this subject has attracted the interest of biologists and the general public, our scientific knowledge on the subject remains fragmentary. In the caterpillar of the swallowtail butterfly Papilio xuthus, spectacular changes in the color pattern are observed; the insect mimics bird droppings (mimetic pattern) as a young larva, and switches to a green camouflage coloration (cryptic pattern) in the final instar. Despite the wide variety and significance of larval color patterns, few studies have been conducted at a molecular level compared with the number of studies on adult butterfly wing patterns. Results To obtain a catalog of genes involved in larval mimetic and cryptic pattern formation, we constructed expressed sequence tag (EST) libraries of larval epidermis for P. xuthus, and P. polytes that contained 20,736 and 5,376 clones, respectively, representing one of the largest collections available in butterflies. A comparison with silkworm epidermal EST information revealed the high expression of putative blue and yellow pigment-binding proteins in Papilio species. We also designed a microarray from the EST dataset information, analyzed more than five stages each for six markings, and confirmed spatial expression patterns by whole-mount in situ hybridization. Hence, we succeeded in elucidating many novel marking-specific genes for mimetic and cryptic pattern formation, including pigment-binding protein genes, the melanin-associated gene yellow-h3, the ecdysteroid synthesis enzyme gene 3-dehydroecdysone 3b-reductase, and Papilio-specific genes. We also found many cuticular protein genes with marking specificity that may be associated with the unique surface nanostructure of the markings. Furthermore, we identified two transcription factors, spalt and ecdysteroid signal-related E75, as genes expressed in larval eyespot markings. This finding suggests that E75 is a strong candidate mediator of the hormone-dependent coordination of larval pattern formation. Conclusions This study is one of the most comprehensive molecular analyses of complicated morphological features, and it will serve as a new resource for studying insect mimetic and cryptic pattern formation in general. The wide variety of marking-associated genes (both regulatory and structural genes) identified by our screening indicates that a similar strategy will be effective for understanding other complex traits. PMID:22651552
Morpho peleides butterfly wing imprints as structural colour stamp.
Zobl, Sigrid; Salvenmoser, Willi; Schwerte, Thorsten; Gebeshuber, Ille C; Schreiner, Manfred
2016-02-02
This study presents the replication of a color-causing nanostructure based on the upper laminae of numerous cover scales of Morpho peleides butterfly wings and obtained solely by imprinting their upper-wing surfaces. Our results indicate that a simple casting technique using a novel integrated release agent can obtain a large positive replica using negative imprints via Polyvinylsiloxane. The developed method is low-tech and high-yield and is thus substantially easier and less expensive than previous methods. The microstructures were investigated with light microscopy, the nanostructures with both scanning and transmission electron microscopy, and the reflections with UV visible spectrometry. The influence of the release agent and the quality of the master stamp were determined by comparing measurements of the cover-scale sizes and their chromaticity values obtained by their images and with their positive imprints. The master stamp provided multiple positive replicas up to 3 cm(2) in just 1 h with structural coloration effects visible to the naked eye. Thus, the developed method proves the accuracy of the replicated nanostructure and its potential industrial application as a color-producing nanostamp.
Butterfly inclusions in Van Schrieck masterpieces. Techniques and optical properties
NASA Astrophysics Data System (ADS)
Berthier, S.; Boulenguez, J.; Menu, M.; Mottin, B.
2008-07-01
Dutch painter Otto Marseus Van Schrieck (1619 1678) is famous for his invention of “sottobosco”. These specific still-life paintings are characterized by the presence of various living organisms (mainly insects and plants) directly on the canvas. We will focus our attention on the painting kept in the museum of Grenoble, France, where a real butterfly is pasted on the canvas. The actual butterfly is a common Nymphalidae, Inachis io, presented in a static position on the dorsal side, without any perspective, compared to the neighboring butterflies. The colors of this butterfly are mainly due to pigments, melanin (black to brown) and ommochromes (yellow, orange, red) often in granules configuration that introduce scattering of light superimposed to the classical selective absorption, except in the ocelli of the hind wings where the blue coloration is due to interferential effects. The nearly perfect refraction index equality between the varnish and the chitin, the main constituent of the butterfly wings, deeply affects its colors. This leads the artist to a final intervention in some parts of the wings, revealed by microscope observation.
Lucas, Lauren K; Nice, Chris C; Gompert, Zachariah
2018-03-13
Patterns of phenotypic variation within and among species can be shaped and constrained by trait genetic architecture. This is particularly true for complex traits, such as butterfly wing patterns, that consist of multiple elements. Understanding the genetics of complex trait variation across species boundaries is difficult, as it necessitates mapping in structured populations and can involve many loci with small or variable phenotypic effects. Here, we investigate the genetic architecture of complex wing pattern variation in Lycaeides butterflies as a case study of mapping multivariate traits in wild populations that include multiple nominal species or groups. We identify conserved modules of integrated wing pattern elements within populations and species. We show that trait covariances within modules have a genetic basis and thus represent genetic constraints that can channel evolution. Consistent with this, we find evidence that evolutionary changes in wing patterns among populations and species occur in the directions of genetic covariances within these groups. Thus, we show that genetic constraints affect patterns of biological diversity (wing pattern) in Lycaeides, and we provide an analytical template for similar work in other systems. © 2018 John Wiley & Sons Ltd.
NASA Technical Reports Server (NTRS)
Parsons-Wingerter, Patricia A.; Hosamani, Ravikumar; Bhattacharya, Sharmila
2015-01-01
Imaginal wing discs of Drosophila melanogaster (fruit fly) defined during embryogenesis ultimately result in mature wings of stereotyped (specific) venation patterning. Major regulators of wing disc development are the epidermal growth factor receptor (EGF), Notch, Hedgehog (Hh), Wingless (Wg), and Dpp signaling pathways. Highly stereotyped vascular patterning is also characteristic of tissues in other organisms flown in space such as the mouse retina and leaves of Arabidopsis thaliana. Genetic and other adaptations of vascular patterning to space environmental factors have not yet been systematically quantified, despite widespread recognition of their critical importance for terrestrial and microgravity applications. Here we report changes in gene expression with space flight related to Drosophila wing morphogenesis and vein patterning. In addition, genetically modified phenotypes of increasingly abnormal ectopic wing venation in the Drosophila wing1 were analyzed by NASA's VESsel GENeration Analysis (VESGEN) software2. Our goal is to further develop insightful vascular mappings associated with bioinformatic dimensions of genetic or other molecular phenotypes for correlation with genetic and other molecular profiling relevant to NASA's GeneLab and other Space Biology exploration initiatives.
Active dendrites: colorful wings of the mysterious butterflies.
Johnston, Daniel; Narayanan, Rishikesh
2008-06-01
Santiago Ramón y Cajal had referred to neurons as the 'mysterious butterflies of the soul.' Wings of these butterflies--their dendrites--were traditionally considered as passive integrators of synaptic information. Owing to a growing body of experimental evidence, it is now widely accepted that these wings are colorful, endowed with a plethora of active conductances, with each family of these butterflies made of distinct hues and shades. Furthermore, rapidly evolving recent literature also provides direct and indirect demonstrations for activity-dependent plasticity of these active conductances, pointing toward chameleonic adaptability in these hues. These experimental findings firmly establish the immense computational power of a single neuron, and thus constitute a turning point toward the understanding of various aspects of neuronal information processing. In this brief historical perspective, we track important milestones in the chameleonic transmogrification of these mysterious butterflies.
Bowsher, Julia H; Wray, Gregory A; Abouheif, Ehab
2007-12-15
Over the last decade, it has become clear that organismal form is largely determined by developmental and evolutionary changes in the growth and pattern formation of tissues. Yet, there is little known about how these two integrated processes respond to environmental cues or how they evolve relative to one another. Here, we present the discovery of vestigial wing imaginal discs in worker larvae of the red imported fire ant, Solenopsis invicta. These vestigial wing discs are present in all worker larvae, which is uncommon for a species with a large worker size distribution. Furthermore, the growth trajectory of these vestigial discs is distinct from all of the ant species examined to date because they grow at a rate slower than the leg discs. We predicted that the growth trajectory of the vestigial wing discs would be mirrored by evolutionary changes in their patterning. We tested this prediction by examining the expression of three patterning genes, extradenticle, ultrabithorax, and engrailed, known to underlie the wing polyphenism in ants. Surprisingly, the expression patterns of these three genes in the vestigial wing discs was the same as those found in ant species with different worker size distributions and wing disc growth than fire ants. We conclude that growth and patterning are evolutionarily dissociated in the vestigial wing discs of S. invicta because patterning in these discs is conserved, whereas their growth trajectories are not. The evolutionary dissociation of growth and patterning may be an important feature of gene networks that underlie polyphenic traits. 2007 Wiley-Liss, Inc
Phenotypic plasticity in the range-margin population of the lycaenid butterfly Zizeeria maha
2010-01-01
Background Many butterfly species have been experiencing the northward range expansion and physiological adaptation, probably due to climate warming. Here, we document an extraordinary field case of a species of lycaenid butterfly, Zizeeria maha, for which plastic phenotypes of wing color-patterns were revealed at the population level in the course of range expansion. Furthermore, we examined whether this outbreak of phenotypic changes was able to be reproduced in a laboratory. Results In the recently expanded northern range margins of this species, more than 10% of the Z. maha population exhibited characteristic color-pattern modifications on the ventral wings for three years. We physiologically reproduced similar phenotypes by an artificial cold-shock treatment of a normal southern population, and furthermore, we genetically reproduced a similar phenotype after selective breeding of a normal population for ten generations, demonstrating that the cold-shock-induced phenotype was heritable and partially assimilated genetically in the breeding line. Similar genetic process might have occurred in the previous and recent range-margin populations as well. Relatively minor modifications expressed in the tenth generation of the breeding line together with other data suggest a role of founder effect in this field case. Conclusions Our results support the notion that the outbreak of the modified phenotypes in the recent range-margin population was primed by the revelation of plastic phenotypes in response to temperature stress and by the subsequent genetic process in the previous range-margin population, followed by migration and temporal establishment of genetically unstable founders in the recent range margins. This case presents not only an evolutionary role of phenotypic plasticity in the field but also a novel evolutionary aspect of range expansion at the species level. PMID:20718993
Integration of wings and their eyespots in the speckled wood butterfly Pararge aegeria.
Breuker, Casper J; Gibbs, Melanie; Van Dyck, Hans; Brakefield, Paul M; Klingenberg, Christian Peter; Van Dongen, Stefan
2007-07-15
We investigated both the phenotypic and developmental integration of eyespots on the fore- and hindwings of speckled wood butterflies Pararge aegeria. Eyespots develop within a framework of wing veins, which may not only separate eyespots developmentally, but may at the same time also integrate them by virtue of being both signalling sources and barriers during eyespot development. We therefore specifically investigated the interaction between wing venation patterns and eyespot integration. Phenotypic covariation among eyespots was very high, but only eyespots in neighbouring wing cells and in homologous wing cells on different wing surfaces were developmentally integrated. This can be explained by the fact that the wing cells of these eyespots share one or more wing veins. The wing venation patterns of fore- and hindwings were highly integrated, both phenotypically and developmentally. This did not affect overall developmental integration of the eyespots. The adaptive significance of integration patterns is discussed and more specifically we stress the need to conduct studies on phenotypic plasticity of integration.
Flow visualization study of a vortex-wing interaction
NASA Technical Reports Server (NTRS)
Mehta, R. D.; Lim, T. T.
1984-01-01
A flow visualization study in water was completed on the interaction of a streamwise vortex with a laminar boundary layer on a two-dimensional wing. The vortex was generated at the tip of a finite wing at incidence, mounted perpendicular to the main wing, and having the same chord as the main wing. The Reynolds number based on wing chord was about 5000. Two different visualization techniques were used. One involved the injection of two different colored dyes into the vortex and the boundary layer. The other technique utilized hydrogen bubbles as an indicator. The position of the vortex was varied in a directional normal to the wing. The angle of attack of the main wing was varied from -5 to +12.5 deg. The vortex induced noticeable cross flows in the wing boundary layer from a distance equivalent to 0.75 chords. When very close to the wing, the vortex entrained boundary layer fluid and caused a cross flow separation which resulted in a secondary vortex.
2013-01-01
Background One of the most intriguing questions in evolutionary developmental biology is how an insect acquires a mimicry pattern within its body parts. A striking example of pattern mimicry is found in the pattern diversity of moth and butterfly wings, which is thought to evolve from preexisting elements illustrated by the nymphalid ground plan (NGP). Previous studies demonstrated that individuality of the NGP facilitates the decoupling of associated common elements, leading to divergence. In contrast, recent studies on the concept of modularity have argued the importance of a combination of coupling and decoupling of the constituent elements. Here, we examine the modularity of a mimicry wing pattern in a moth and explore an evolvable characteristic of the NGP. Results This study examined the wings of the noctuid moth Oraesia excavata, which closely resemble leaves with a leaf venation pattern. Based on a comparative morphological procedure, we found that this leaf pattern was formed by the NGP common elements. Using geometric morphometrics combined with network analysis, we found that each of the modules in the leaf pattern integrates the constituent components of the leaf venation pattern (i.e., the main and lateral veins). Moreover, the detected modules were established by coupling different common elements and decoupling even a single element into different modules. The modules of the O. excavata wing pattern were associated with leaf mimicry, not with the individuality of the NGP common elements. For comparison, we also investigated the modularity of a nonmimetic pattern in the noctuid moth Thyas juno. Quantitative analysis demonstrated that the modules of the T. juno wing pattern regularly corresponded to the individuality of the NGP common elements, unlike those in the O. excavata wing pattern. Conclusions This study provides the first evidence for modularity in a leaf mimicry pattern. The results suggest that the evolution of this pattern involves coupling and decoupling processes to originate these modules, free from the individuality of the NGP system. We propose that this evolution has been facilitated by a versatile characteristic of the NGP, allowing the association of freely modifiable subordinate common elements to make modules. PMID:23890367
2011-01-01
Background Heliconius butterflies are an excellent system for studies of adaptive convergent and divergent phenotypic traits. Wing colour patterns are used as signals to both predators and potential mates and are inherited in a Mendelian manner. The underlying genetic mechanisms of pattern formation have been studied for many years and shed light on broad issues, such as the repeatability of evolution. In Heliconius melpomene, the yellow hindwing bar is controlled by the HmYb locus. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression that have key roles in many biological processes, including development. miRNAs could act as regulators of genes involved in wing development, patterning and pigmentation. For this reason we characterised miRNAs in developing butterfly wings and examined differences in their expression between colour pattern races. Results We sequenced small RNA libraries from two colour pattern races and detected 142 Heliconius miRNAs with homology to others found in miRBase. Several highly abundant miRNAs were differentially represented in the libraries between colour pattern races. These candidates were tested further using Northern blots, showing that differences in expression were primarily due to developmental stage rather than colour pattern. Assembly of sequenced reads to the HmYb region identified hme-miR-193 and hme-miR-2788; located 2380 bp apart in an intergenic region. These two miRNAs are expressed in wings and show an upregulation between 24 and 72 hours post-pupation, indicating a potential role in butterfly wing development. A search for miRNAs in all available H. melpomene BAC sequences (~ 2.5 Mb) did not reveal any other miRNAs and no novel miRNAs were predicted. Conclusions Here we describe the first butterfly miRNAs and characterise their expression in developing wings. Some show differences in expression across developing pupal stages and may have important functions in butterfly wing development. Two miRNAs were located in the HmYb region and were expressed in developing pupal wings. Future work will examine the expression of these miRNAs in different colour pattern races and identify miRNA targets among wing patterning genes. PMID:21266089
Surridge, Alison K; Lopez-Gomollon, Sara; Moxon, Simon; Maroja, Luana S; Rathjen, Tina; Nadeau, Nicola J; Dalmay, Tamas; Jiggins, Chris D
2011-01-26
Heliconius butterflies are an excellent system for studies of adaptive convergent and divergent phenotypic traits. Wing colour patterns are used as signals to both predators and potential mates and are inherited in a Mendelian manner. The underlying genetic mechanisms of pattern formation have been studied for many years and shed light on broad issues, such as the repeatability of evolution. In Heliconius melpomene, the yellow hindwing bar is controlled by the HmYb locus. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression that have key roles in many biological processes, including development. miRNAs could act as regulators of genes involved in wing development, patterning and pigmentation. For this reason we characterised miRNAs in developing butterfly wings and examined differences in their expression between colour pattern races. We sequenced small RNA libraries from two colour pattern races and detected 142 Heliconius miRNAs with homology to others found in miRBase. Several highly abundant miRNAs were differentially represented in the libraries between colour pattern races. These candidates were tested further using Northern blots, showing that differences in expression were primarily due to developmental stage rather than colour pattern. Assembly of sequenced reads to the HmYb region identified hme-miR-193 and hme-miR-2788; located 2380 bp apart in an intergenic region. These two miRNAs are expressed in wings and show an upregulation between 24 and 72 hours post-pupation, indicating a potential role in butterfly wing development. A search for miRNAs in all available H. melpomene BAC sequences (~2.5 Mb) did not reveal any other miRNAs and no novel miRNAs were predicted. Here we describe the first butterfly miRNAs and characterise their expression in developing wings. Some show differences in expression across developing pupal stages and may have important functions in butterfly wing development. Two miRNAs were located in the HmYb region and were expressed in developing pupal wings. Future work will examine the expression of these miRNAs in different colour pattern races and identify miRNA targets among wing patterning genes.
Ferguson, Laura C; Maroja, Luana; Jiggins, Chris D
2011-12-01
The evolution of pigmentation in vertebrates and flies has involved repeated divergence at a small number of genes related to melanin synthesis. Here, we study insect melanin synthesis genes in Heliconius butterflies, a group characterised by its diversity of wing patterns consisting of black (melanin), and yellow and red (ommochrome) pigmented scales. Consistent with their respective biochemical roles in Drosophila melanogaster, ebony is upregulated in non-melanic wing regions destined to be pigmented red whilst tan is upregulated in melanic regions. Wing regions destined to be pigmented yellow, however, are downregulated for both genes. This pattern is conserved across multiple divergent and convergent phenotypes within the Heliconii, suggesting a conserved mechanism for the development of black, red and yellow pattern elements across the genus. Linkage mapping of five melanin biosynthesis genes showed that, in contrast to other organisms, these genes do not control pattern polymorphism. Thus, the pigmentation genes themselves are not the locus of evolutionary change but lie downstream of a wing pattern regulatory factor. The results suggest a modular system in which particular combinations of genes are switched on whenever red, yellow or black pattern elements are favoured by natural selection for diverse and mimetic wing patterns. © Springer-Verlag 2011
Photonic effects in natural nanostructures
NASA Astrophysics Data System (ADS)
Rey GonzáLez, Rafael Ramón; Barrera Patiã+/-O, Claudia Patricia
Nature exhibits a great variety of structures and nanostructures. In particular the interaction light-matter has a strong dependence with the shape of the nanostructures. In some cases, in the so called structural color, ordered arrays of nanostructures play a very critical role. One of the most interesting color effects is the iridescence, the angular dependence of the observed color in some species of butterflies, insects, plants, beetles, fishes, birds and even in minerals. In the last years, iridescence has been related with photonic properties. In the present work, we present a theoretical study of the photonic properties for different patterns that exist in natural nanostructures present in wings of butterflies that exhibit iridescence. The nanostructures observed in these cases present spatial variations of the dielectric constant that are possible to model them as 1D and 2D photonic crystal. Partial photonic gaps are found as function of lattice constant, dielectric contrast and geometrical configuration. Also, disordered effects are considered. Authors would like to thank the División de Investigación Sede Bogotá for their financial support at Universidad Nacional de Colombia.
Pretreated Butterfly Wings for Tuning the Selective Vapor Sensing.
Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter
2016-09-07
Photonic nanoarchitectures occurring in the scales of Blue butterflies are responsible for their vivid blue wing coloration. These nanoarchitectures are quasi-ordered nanocomposites which are constituted from a chitin matrix with embedded air holes. Therefore, they can act as chemically selective sensors due to their color changes when mixing volatile vapors in the surrounding atmosphere which condensate into the nanoarchitecture through capillary condensation. Using a home-built vapor-mixing setup, the spectral changes caused by the different air + vapor mixtures were efficiently characterized. It was found that the spectral shift is vapor-specific and proportional with the vapor concentration. We showed that the conformal modification of the scale surface by atomic layer deposition and by ethanol pretreatment can significantly alter the optical response and chemical selectivity, which points the way to the efficient production of sensor arrays based on the knowledge obtained through the investigation of modified butterfly wings.
Pretreated Butterfly Wings for Tuning the Selective Vapor Sensing
Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter
2016-01-01
Photonic nanoarchitectures occurring in the scales of Blue butterflies are responsible for their vivid blue wing coloration. These nanoarchitectures are quasi-ordered nanocomposites which are constituted from a chitin matrix with embedded air holes. Therefore, they can act as chemically selective sensors due to their color changes when mixing volatile vapors in the surrounding atmosphere which condensate into the nanoarchitecture through capillary condensation. Using a home-built vapor-mixing setup, the spectral changes caused by the different air + vapor mixtures were efficiently characterized. It was found that the spectral shift is vapor-specific and proportional with the vapor concentration. We showed that the conformal modification of the scale surface by atomic layer deposition and by ethanol pretreatment can significantly alter the optical response and chemical selectivity, which points the way to the efficient production of sensor arrays based on the knowledge obtained through the investigation of modified butterfly wings. PMID:27618045
apterous A specifies dorsal wing patterns and sexual traits in butterflies
2018-01-01
Butterflies have evolved different colour patterns on their dorsal and ventral wing surfaces to serve different signalling functions, yet the developmental mechanisms controlling surface-specific patterning are still unknown. Here, we mutate both copies of the transcription factor apterous in Bicyclus anynana butterflies using CRISPR/Cas9 and show that apterous A, expressed dorsally, functions both as a repressor and modifier of ventral wing colour patterns, as well as a promoter of dorsal sexual ornaments in males. We propose that the surface-specific diversification of wing patterns in butterflies proceeded via the co-option of apterous A or its downstream effectors into various gene regulatory networks involved in the differentiation of discrete wing traits. Further, interactions between apterous and sex-specific factors such as doublesex may have contributed to the origin of sexually dimorphic surface-specific patterns. Finally, we discuss the evolution of eyespot number diversity in the family Nymphalidae within the context of developmental constraints due to apterous regulation. PMID:29467265
Woodcock age and sex determination from wings
Martin, F.W.
1964-01-01
Age of woodcock (Philohela minor) can be accurately determined throughout the year by differences in pattern, color, and wear of secondary feathers. Immature woodcock retain most secondaries during the postjuvenal molt that begins in July or August and ends in October. In contrast, subadults (first-year adults) and older woodcock molt all secondaries during the postnuptial molt beginning in June or July and ending in October. Retention of juvenal secondaries by immatures and molt of these feathers by adults form the basis for age determination. Sex of woodcock can be accurately determined by width of the outer three primaries, which are conspicuously narrower on males.
Asymmetric hindwing foldings in rove beetles.
Saito, Kazuya; Yamamoto, Shuhei; Maruyama, Munetoshi; Okabe, Yoji
2014-11-18
Foldable wings of insects are the ultimate deployable structures and have attracted the interest of aerospace engineering scientists as well as entomologists. Rove beetles are known to fold their wings in the most sophisticated ways that have right-left asymmetric patterns. However, the specific folding process and the reason for this asymmetry remain unclear. This study reveals how these asymmetric patterns emerge as a result of the folding process of rove beetles. A high-speed camera was used to reveal the details of the wing-folding movement. The results show that these characteristic asymmetrical patterns emerge as a result of simultaneous folding of overlapped wings. The revealed folding mechanisms can achieve not only highly compact wing storage but also immediate deployment. In addition, the right and left crease patterns are interchangeable, and thus each wing internalizes two crease patterns and can be folded in two different ways. This two-way folding gives freedom of choice for the folding direction to a rove beetle. The use of asymmetric patterns and the capability of two-way folding are unique features not found in artificial structures. These features have great potential to extend the design possibilities for all deployable structures, from space structures to articles of daily use.
Tamáska, István; Kértész, Krisztién; Vértesy, Zofia; Bálint, Zsolt; Kun, András; Yen, ShenHorn; Biró, Lászlo Péter
2013-01-01
The effects produced by the condensation of water vapor from the environment in the various intricate nanoarchitectures occurring in the wing scales of several Lepidoptera species were investigated by controlled cooling (from 23° C, room temperature to -5 to -10° C) combined with in situ measurements of changes in the reflectance spectra. It was determined that all photonic nanoarchitectures giving a reflectance maximum in the visible range and having an open nanostructure exhibited alteration of the position of the reflectance maximum associated with the photonic nanoarchitectures. The photonic nanoarchitectures with a closed structure exhibited little to no alteration in color. Similarly, control specimens colored by pigments did not exhibit a color change under the same conditions. Hence, this method can be used to identify species with open photonic nanoarchitectures in their scales. For certain species, an almost complete disappearance of the reflectance maximum was found. All specimens recovered their original colors following warming and drying. Cooling experiments using thin copper wires demonstrated that color alterations could be limited to a width of a millimeter or less. Dried museum specimens did not exhibit color changes when cooled in the absence of a heat sink due to the low heat capacity of the wings. PMID:24206534
Tamáska, István; Kértész, Krisztién; Vértesy, Zofia; Bálint, Zsolt; Kun, András; Yen, Shenhorn; Biró, Lászlo Péter
2013-01-01
The effects produced by the condensation of water vapor from the environment in the various intricate nanoarchitectures occurring in the wing scales of several Lepidoptera species were investigated by controlled cooling (from 23° C, room temperature to -5 to -10° C) combined with in situ measurements of changes in the reflectance spectra. It was determined that all photonic nanoarchitectures giving a reflectance maximum in the visible range and having an open nanostructure exhibited alteration of the position of the reflectance maximum associated with the photonic nanoarchitectures. The photonic nanoarchitectures with a closed structure exhibited little to no alteration in color. Similarly, control specimens colored by pigments did not exhibit a color change under the same conditions. Hence, this method can be used to identify species with open photonic nanoarchitectures in their scales. For certain species, an almost complete disappearance of the reflectance maximum was found. All specimens recovered their original colors following warming and drying. Cooling experiments using thin copper wires demonstrated that color alterations could be limited to a width of a millimeter or less. Dried museum specimens did not exhibit color changes when cooled in the absence of a heat sink due to the low heat capacity of the wings.
Investigation of Surface Enhanced Coherent Raman Scattering on Nano-patterned Insect Wings
NASA Astrophysics Data System (ADS)
Ujj, Laszlo; Lawhead, Carlos
2015-03-01
Many insect wings (cicadas, butterflies, mosquitos) poses nano-patterned surface structure. Characterization of surface morphology and chemical composition of insect wings is important to understand the extreme mechanical properties and the biophysical functionalities of the wings. We have measured the image of the membrane of a cicada's wing with the help of Scanning Electron Microscopy (SEM). The results confirm the existing periodic structure of the wing measured previously. In order to identify the chemical composition of the wing, we have deposited silver nanoparticles on it and applied Coherent anti-Stokes Raman Spectroscopy to measure the vibrational spectra of the molecules comprising the wing for the first time. The measured spectra are consistent with the original assumption that the wing membrane is composed of protein, wax, and chitin. The results of these studies can be used to measure other nano-patterned surfaces and to make artificial materials in the future. Authors grateful for financial support from the Department of Physics of the College of Sciences Engineering and Health of UWF and the Pall Corporation for SEM imaging.
Lee, Yong-Keun; Bin, Yu
2016-01-01
Since the color of esthetic brackets should match that of teeth, the aims of this study were to determine the color and translucency of esthetic brackets by means of the clinically relevant use of a spectroradiometer, and to compare the color of brackets with that of a commercial shade guide. The color of central and tie-wing regions of four plastic and four ceramic brackets was measured according to the CIE L*a*b* color scale over white and black backgrounds. Brackets were classified into five groups based on their composition. The color of Vitapan Classical Shade Guide tabs was also measured. Translucency parameter (TP) and contrast ratio (CR) were calculated to determine translucency. Color differences between brackets and the shade guide tabs were 10.4 - 34.5 ∆E*ab units. TP and CR values for the central region were 16.4 - 27.7 and 0.38 - 0.58, whereas for the tie-wings they were 24.0 - 39.9 and 0.25 - 0.45, respectively. The color coordinates, TP and CR values were significantly influenced by bracket composition and brand (p < 0.05). Esthetic brackets investigated herein showed unacceptable color differences (∆E*ab > 5.5) compared with the shade guide tabs. Differences in the translucency of brackets by brand were within the visually perceptible range (∆CR > 0.07). Therefore, brackets showing the best matching performance for each case should be selected considering esthetic and functional demands.
Yoshioka, Shinya; Kinoshita, Shuichi
2006-01-22
A few species of Morpho butterflies have a distinctive white stripe pattern on their structurally coloured blue wings. Since the colour pattern of a butterfly wing is formed as a mosaic of differently coloured scales, several questions naturally arise: are the microstructures the same between the blue and white scales? How is the distinctive whiteness produced, structurally or by means of pigmentation? To answer these questions, we have performed structural and optical investigations of the stripe pattern of a butterfly, Morpho cypris. It is found that besides the dorsal and ventral scale layers, the wing substrate also has the corresponding stripe pattern. Quantitative optical measurements and analysis using a simple model for the wing structure reveal the origin of the higher reflectance which makes the white stripe brighter.
Investigating Nanoscopic Structures on a Butterfly Wing to Explore Solvation and Coloration
ERIC Educational Resources Information Center
Bober, Brittany A.; Ogata, Jennifer K.; Martinez, Veronica E.; Hallinan, Janae J.; Leach, Taylor A.; Negru, Bogdan
2018-01-01
Surface structures on the nanometer size scale can impart new and exciting properties to bulk materials. Nanoscopic structures on hydrophobic materials can result in superhydrophobicity and structural coloration. We present an interdisciplinary experiment that introduces undergraduate students to nanotechnology by manipulating the…
Imafuku, Michio; Ogihara, Naomichi
2016-12-01
There have been only a few reports on the directional reflection of light by butterfly wings. Here, we systematically investigated this phenomenon in a lycaenid butterfly, Chrysozephyrus smaragdinus,in which males have bright green wings based on structural coloration. We used a device that measures intensities of light in hemispherical space by vertical shifting of a sensor and horizontal rotation of the stage carrying the wing, which is illuminated from the top, to determine the direction of light reflected by the fore- and hindwings. The orientation and curvature of wing scales were also examined microscopically. The forewing of this species reflected light shone from the top largely forward, whereas the hindwing reflected it slightly forward. This difference was attributed to the tilt angles of the wing scales. Light reflection by the forewing was relatively weak, and widely scattered, whereas that by the hindwing was rather concentrated, resulting in higher reflectance. This difference was attributed to difference in the curvature of the wing scales on the two wings.
[Transverse folding and the evolution of hind wings in beetles (Insecta, Coleoptera)].
Fedorenko, D N
2013-01-01
Strong intensification of the protective function of the fore wing in Coleoptera has made their flight apparatus a posteromotoric one and invited an apparatus responsible for folding the hindwings beneath the elytra to develop. Folding apparatus could hardly develop without higher deformability of veins or their parts, which diminished strength properties of the wing support. The effect was stressed by folds that intersected veins. Organization of the folds into a system confined this negative influence to a few wing regions and some veinal sections. This having happened, wing support and folding pattern evolved interrelated, the former into being more flexible, with no or minimum loss of rigidity, and the latter towards being less harmful for the supporting elements, especially axial ones. Monofunctionality, together with very simple structure and little specialization of constituent parts, made the folding pattern very labile during evolution. The folding pattern evolved more rapidly than wing venation, thus defining transformations of the latter. Evolutionary conservatism of wing venation stemmed from that many veins were strongly specialized in performing two conflicting functions. An adaptive compromise was necessary for the conflict to be solved, which determined the wing to orthogenetic development. The main evolutionary trends for wing venation and folding pattern were those towards simplification and a higher complexity, respectively. The beetle wing has passed through two main evolutionary stages. Among them, the first resulted in the development of the "Archostemata" wing type, the second started from the "cantharoid" structural plan. The main evolutionary factors were the infancies of wing posteromotorism at the first stage while the wing strongly influenced by size evolution, with the main trend towards miniaturization, at the second. The archostematan and "cantharoid" morphofunctional wing types differ fundamentally. In the wing of the former kind, folding and flight apparatus, because of considerably overlapping supporting systems, constitute a lasting coadaptive ensemble, with only minor deviations from the ground-plan occurring through evolution. The uprise of the "cantharoid" wing type was an upgrade of morpho-functional organization. The region of maximum transverse deformations having been extruded from the remigium basal part, chief supporting axes of the wing increased their rigid properties. The supporting systems of the two wing apparatus became more autonomous, having been separated. This expanded the adaptive zone for the wing strongly, which a great variety of derived wing types have emerged from.
Variation in gypsy moth, with comparisons to other Lymantria spp.
Paul W. Schaefer
1991-01-01
Specimens of gypsy moth, Lymantria dispar (L.) sensu lato were displayed in museum trays. Many specimens were quarantine laboratory reared during the 1989 season to provide samples (wing venation, frozen adults, prepupal haemolymph, larval feeding behavior, egg mass hair color, head capsule coloration and larval development) for...
Lee, Yong-Keun; Bin, Yu
2016-01-01
ABSTRACT Objective: Since the color of esthetic brackets should match that of teeth, the aims of this study were to determine the color and translucency of esthetic brackets by means of the clinically relevant use of a spectroradiometer, and to compare the color of brackets with that of a commercial shade guide. Methods: The color of central and tie-wing regions of four plastic and four ceramic brackets was measured according to the CIE L*a*b* color scale over white and black backgrounds. Brackets were classified into five groups based on their composition. The color of Vitapan Classical Shade Guide tabs was also measured. Translucency parameter (TP) and contrast ratio (CR) were calculated to determine translucency. Results: Color differences between brackets and the shade guide tabs were 10.4 - 34.5 ∆E*ab units. TP and CR values for the central region were 16.4 - 27.7 and 0.38 - 0.58, whereas for the tie-wings they were 24.0 - 39.9 and 0.25 - 0.45, respectively. The color coordinates, TP and CR values were significantly influenced by bracket composition and brand (p < 0.05). Conclusions: Esthetic brackets investigated herein showed unacceptable color differences (∆E*ab > 5.5) compared with the shade guide tabs. Differences in the translucency of brackets by brand were within the visually perceptible range (∆CR > 0.07). Therefore, brackets showing the best matching performance for each case should be selected considering esthetic and functional demands. PMID:27275619
Mateus, Ana Rita A; Marques-Pita, Manuel; Oostra, Vicencio; Lafuente, Elvira; Brakefield, Paul M; Zwaan, Bas J; Beldade, Patrícia
2014-11-21
The environmental regulation of development can result in the production of distinct phenotypes from the same genotype and provide the means for organisms to cope with environmental heterogeneity. The effect of the environment on developmental outcomes is typically mediated by hormonal signals which convey information about external cues to the developing tissues. While such plasticity is a wide-spread property of development, not all developing tissues are equally plastic. To understand how organisms integrate environmental input into coherent adult phenotypes, we must know how different body parts respond, independently or in concert, to external cues and to the corresponding internal signals. We quantified the effect of temperature and ecdysone hormone manipulations on post-growth tissue patterning in an experimental model of adaptive developmental plasticity, the butterfly Bicyclus anynana. Following a suite of traits evolving by natural or sexual selection, we found that different groups of cells within the same tissue have sensitivities and patterns of response that are surprisingly distinct for the external environmental cue and for the internal hormonal signal. All but those wing traits presumably involved in mate choice responded to developmental temperature and, of those, all but the wing traits not exposed to predators responded to hormone manipulations. On the other hand, while patterns of significant response to temperature contrasted traits on autonomously-developing wings, significant response to hormone manipulations contrasted neighboring groups of cells with distinct color fates. We also showed that the spatial compartmentalization of these responses cannot be explained by the spatial or temporal compartmentalization of the hormone receptor protein. Our results unravel the integration of different aspects of the adult phenotype into developmental and functional units which both reflect and impact evolutionary change. Importantly, our findings underscore the complexity of the interactions between environment and physiology in shaping the development of different body parts.
Independently Controlled Wing Stroke Patterns in the Fruit Fly Drosophila melanogaster
Chakraborty, Soma; Bartussek, Jan; Fry, Steven N.; Zapotocky, Martin
2015-01-01
Flies achieve supreme flight maneuverability through a small set of miniscule steering muscles attached to the wing base. The fast flight maneuvers arise from precisely timed activation of the steering muscles and the resulting subtle modulation of the wing stroke. In addition, slower modulation of wing kinematics arises from changes in the activity of indirect flight muscles in the thorax. We investigated if these modulations can be described as a superposition of a limited number of elementary deformations of the wing stroke that are under independent physiological control. Using a high-speed computer vision system, we recorded the wing motion of tethered flying fruit flies for up to 12 000 consecutive wing strokes at a sampling rate of 6250 Hz. We then decomposed the joint motion pattern of both wings into components that had the minimal mutual information (a measure of statistical dependence). In 100 flight segments measured from 10 individual flies, we identified 7 distinct types of frequently occurring least-dependent components, each defining a kinematic pattern (a specific deformation of the wing stroke and the sequence of its activation from cycle to cycle). Two of these stroke deformations can be associated with the control of yaw torque and total flight force, respectively. A third deformation involves a change in the downstroke-to-upstroke duration ratio, which is expected to alter the pitch torque. A fourth kinematic pattern consists in the alteration of stroke amplitude with a period of 2 wingbeat cycles, extending for dozens of cycles. Our analysis indicates that these four elementary kinematic patterns can be activated mutually independently, and occur both in isolation and in linear superposition. The results strengthen the available evidence for independent control of yaw torque, pitch torque, and total flight force. Our computational method facilitates systematic identification of novel patterns in large kinematic datasets. PMID:25710715
Independently controlled wing stroke patterns in the fruit fly Drosophila melanogaster.
Chakraborty, Soma; Bartussek, Jan; Fry, Steven N; Zapotocky, Martin
2015-01-01
Flies achieve supreme flight maneuverability through a small set of miniscule steering muscles attached to the wing base. The fast flight maneuvers arise from precisely timed activation of the steering muscles and the resulting subtle modulation of the wing stroke. In addition, slower modulation of wing kinematics arises from changes in the activity of indirect flight muscles in the thorax. We investigated if these modulations can be described as a superposition of a limited number of elementary deformations of the wing stroke that are under independent physiological control. Using a high-speed computer vision system, we recorded the wing motion of tethered flying fruit flies for up to 12,000 consecutive wing strokes at a sampling rate of 6250 Hz. We then decomposed the joint motion pattern of both wings into components that had the minimal mutual information (a measure of statistical dependence). In 100 flight segments measured from 10 individual flies, we identified 7 distinct types of frequently occurring least-dependent components, each defining a kinematic pattern (a specific deformation of the wing stroke and the sequence of its activation from cycle to cycle). Two of these stroke deformations can be associated with the control of yaw torque and total flight force, respectively. A third deformation involves a change in the downstroke-to-upstroke duration ratio, which is expected to alter the pitch torque. A fourth kinematic pattern consists in the alteration of stroke amplitude with a period of 2 wingbeat cycles, extending for dozens of cycles. Our analysis indicates that these four elementary kinematic patterns can be activated mutually independently, and occur both in isolation and in linear superposition. The results strengthen the available evidence for independent control of yaw torque, pitch torque, and total flight force. Our computational method facilitates systematic identification of novel patterns in large kinematic datasets.
Evolutionary-Optimized Photonic Network Structure in White Beetle Wing Scales.
Wilts, Bodo D; Sheng, Xiaoyuan; Holler, Mirko; Diaz, Ana; Guizar-Sicairos, Manuel; Raabe, Jörg; Hoppe, Robert; Liu, Shu-Hao; Langford, Richard; Onelli, Olimpia D; Chen, Duyu; Torquato, Salvatore; Steiner, Ullrich; Schroer, Christian G; Vignolini, Silvia; Sepe, Alessandro
2018-05-01
Most studies of structural color in nature concern periodic arrays, which through the interference of light create color. The "color" white however relies on the multiple scattering of light within a randomly structured medium, which randomizes the direction and phase of incident light. Opaque white materials therefore must be much thicker than periodic structures. It is known that flying insects create "white" in extremely thin layers. This raises the question, whether evolution has optimized the wing scale morphology for white reflection at a minimum material use. This hypothesis is difficult to prove, since this requires the detailed knowledge of the scattering morphology combined with a suitable theoretical model. Here, a cryoptychographic X-ray tomography method is employed to obtain a full 3D structural dataset of the network morphology within a white beetle wing scale. By digitally manipulating this 3D representation, this study demonstrates that this morphology indeed provides the highest white retroreflection at the minimum use of material, and hence weight for the organism. Changing any of the network parameters (within the parameter space accessible by biological materials) either increases the weight, increases the thickness, or reduces reflectivity, providing clear evidence for the evolutionary optimization of this morphology. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Bai, Linge; Widmann, Thomas; Jülicher, Frank; Dahmann, Christian; Breen, David
2013-01-01
Quantifying and visualizing the shape of developing biological tissues provide information about the morphogenetic processes in multicellular organisms. The size and shape of biological tissues depend on the number, size, shape, and arrangement of the constituting cells. To better understand the mechanisms that guide tissues into their final shape, it is important to investigate the cellular arrangement within tissues. Here we present a data processing pipeline to generate 3D volumetric surface models of epithelial tissues, as well as geometric descriptions of the tissues' apical cell cross-sections. The data processing pipeline includes image acquisition, editing, processing and analysis, 2D cell mesh generation, 3D contourbased surface reconstruction, cell mesh projection, followed by geometric calculations and color-based visualization of morphological parameters. In their first utilization we have applied these procedures to construct a 3D volumetric surface model at cellular resolution of the wing imaginal disc of Drosophila melanogaster. The ultimate goal of the reported effort is to produce tools for the creation of detailed 3D geometric models of the individual cells in epithelial tissues. To date, 3D volumetric surface models of the whole wing imaginal disc have been created, and the apicolateral cell boundaries have been identified, allowing for the calculation and visualization of cell parameters, e.g. apical cross-sectional area of cells. The calculation and visualization of morphological parameters show position-dependent patterns of cell shape in the wing imaginal disc. Our procedures should offer a general data processing pipeline for the construction of 3D volumetric surface models of a wide variety of epithelial tissues.
Structural color mechanism in the Papilio blumei butterfly.
Lo, Mei-Ling; Lee, Cheng-Chung
2014-02-01
The structural color found in biological systems has complicated nanostructure. It is very important to determine its color mechanism. In this study, the 2D photonic crystal structures of the Papilio blumei butterfly were constructed, and the corresponding reflectance spectra were simulated by the finite-difference time-domain method. The structural color of the butterfly depends on the incident angle of light, film thickness, film material (film refractive index), and the size of the air hole (effective refractive index). Analysis of simulations can help us understand the hue, brightness, and saturation of structural color on the butterfly wing. As a result, the analysis can help us fabricate expected structural color.
USDA-ARS?s Scientific Manuscript database
The nymphalid groundplan (NGP) is an idealized system used to classify and interpret wing pattern elements of butterflies. Nearly a century ago, the principles of the NGP were applied to the wing patterns of higher moths (Macroheterocera). Recent advances in phylogeny and in the comparative morpholo...
Bischoff, Kara; Ballew, Anna C.; Simon, Michael A.; O'Reilly, Alana M.
2009-01-01
Background The coordinated action of genes that control patterning, cell fate determination, cell size, and cell adhesion is required for proper wing formation in Drosophila. Defects in any of these basic processes can lead to wing aberrations, including blisters. The xenicid mutation was originally identified in a screen designed to uncover regulators of adhesion between wing surfaces [1]. Principal Findings Here, we demonstrate that expression of the βPS integrin or the patterning protein Engrailed are not affected in developing wing imaginal discs in xenicid mutants. Instead, expression of the homeotic protein Ultrabithorax (Ubx) is strongly increased in xenicid mutant cells. Conclusion Our results suggest that upregulation of Ubx transforms cells from a wing blade fate to a haltere fate, and that the presence of haltere cells within the wing blade is the primary defect leading to the adult wing phenotypes observed. PMID:19956620
Reproduction and optical analysis of Morpho-inspired polymeric nanostructures
NASA Astrophysics Data System (ADS)
Tippets, Cary A.; Fu, Yulan; Jackson, Anne-Martine; Donev, Eugenii U.; Lopez, Rene
2016-06-01
The brilliant blue coloration of the Morpho rhetenor butterfly originates from complex nanostructures found on the surface of its wings. The Morpho butterfly exhibits strong short-wavelength reflection and a unique two-lobe optical signature in the incident (θ) and reflected (ϕ) angular space. Here, we report the large-area fabrication of a Morpho-like structure and its reproduction in perfluoropolyether. Reflection comparisons of periodic and quasi-random ‘polymer butterfly’ nanostructures show similar normal-incidence spectra but differ in the angular θ-ϕ dependence. The periodic sample shows strong specular reflection and simple diffraction. However, the quasi-random sample produces a two-lobe angular reflection pattern with minimal specular refection, approximating the real butterfly’s optical behavior. Finite-difference time-domain simulations confirm that this pattern results from the quasi-random periodicity and highlights the significance of the inherent randomness in the Morpho’s photonic structure.
Some observations of separated flow on finite wings
NASA Technical Reports Server (NTRS)
Winkelmann, A. E.; Ngo, H. T.; De Seife, R. C.
1982-01-01
Wind tunnel test results for aspects of flow over airfoils exhibiting single and multiple trailing edge stall 'mushroom' cells are reported. Rectangular wings with aspect ratios of 4.0 and 9.0 were tested at Reynolds numbers of 480,000 and 257,000, respectively. Surface flow patterns were visualized by means of a fluorescent oil flow technique, separated flow was observed with a tuft wand and a water probe, spanwise flow was studied with hot-wire anemometry, smoke flow and an Ar laser illuminated the centerplane flow, and photographs were made of the oil flow patterns. Swirl patterns on partially and fully stalled wings suggested vortex flow attachments in those regions, and a saddle point on the fully stalled AR=4.0 wing indicated a secondary vortex flow at the forward region of the separation bubble. The separation wake decayed downstream, while the tip vortex interacted with the separation bubble on the fully stalled wing. Three mushroom cells were observed on the AR=9.0 wing.
2009-04-30
The Green Hairstreak butterfly has ventrally scales consisting of 3D gyroid domains acting as photonic crystals, which can be easily...study on the structural coloration of the Green Hairstreak , Callophrys rubi. Extensive experimental measurements have been complemented with three...colorations, produced by purely dielectric materials are widely encountered [1-3]. Famous examples are the metallic- green buprestid and golden scarab
K.F Connor
2004-01-01
Shining sumac is an upright, deciduous, clonal shrub or (rarely) small tree from 3 to 6 m tall. Bark ranges in color from light brown to gray to reddish-brown. Shoots and twigs are hairy and reddish in color. Twigs have conspicuous lenticels. The sparsely branched, flat crown is composed of alternate, pinnately compound leaves approximately 15 to 30 cm long, with wings...
Flexible, angle-independent, structural color reflectors inspired by morpho butterfly wings.
Chung, Kyungjae; Yu, Sunkyu; Heo, Chul-Joon; Shim, Jae Won; Yang, Seung-Man; Han, Moon Gyu; Lee, Hong-Seok; Jin, Yongwan; Lee, Sang Yoon; Park, Namkyoo; Shin, Jung H
2012-05-08
Thin-film color reflectors inspired by Morpho butterflies are fabricated. Using a combination of directional deposition, silica microspheres with a wide size distribution, and a PDMS (polydimethylsiloxane) encasing, a large, flexible reflector is created that actually provides better angle-independent color characteristics than Morpho butterflies and which can even be bent and folded freely without losing its Morpho-mimetic photonic properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Schunk, Cosima; Swartz, Sharon M; Breuer, Kenneth S
2017-02-06
Aspect ratio (AR) is one parameter used to predict the flight performance of a bat species based on wing shape. Bats with high AR wings are thought to have superior lift-to-drag ratios and are therefore predicted to be able to fly faster or to sustain longer flights. By contrast, bats with lower AR wings are usually thought to exhibit higher manoeuvrability. However, the half-span ARs of most bat wings fall into a narrow range of about 2.5-4.5. Furthermore, these predictions do not take into account the wide variation in flapping motion observed in bats. To examine the influence of different stroke patterns, we measured lift and drag of highly compliant membrane wings with different bat-relevant ARs. A two degrees of freedom shoulder joint allowed for independent control of flapping amplitude and wing sweep. We tested five models with the same variations of stroke patterns, flapping frequencies and wind speed velocities. Our results suggest that within the relatively small AR range of bat wings, AR has no clear effect on force generation. Instead, the generation of lift by our simple model mostly depends on wingbeat frequency, flapping amplitude and freestream velocity; drag is mostly affected by the flapping amplitude.
Nanostructured Antireflective and Thermoisolative Cicada Wings.
Morikawa, Junko; Ryu, Meguya; Seniutinas, Gediminas; Balčytis, Armandas; Maximova, Ksenia; Wang, Xuewen; Zamengo, Massimiliano; Ivanova, Elena P; Juodkazis, Saulius
2016-05-10
Inter-related mechanical, thermal, and optical macroscopic properties of biomaterials are defined at the nanoscale by their constituent structures and patterns, which underpin complex functions of an entire bio-object. Here, the temperature diffusivity of a cicada (Cyclochila australasiae) wing with nanotextured surfaces was measured using two complementary techniques: a direct contact method and IR imaging. The 4-6-μm-thick wing section was shown to have a thermal diffusivity of α⊥ = (0.71 ± 0.15) × 10(-7) m(2)/s, as measured by the contact temperature wave method along the thickness of the wing; it corresponds to the inherent thermal property of the cuticle. The in-plane thermal diffusivity value of the wing was determined by IR imaging and was considerably larger at α∥ = (3.6 ± 0.2) × 10(-7) m(2)/s as a result of heat transport via air. Optical properties of wings covered with nanospikes were numerically simulated using an accurate 3D model of the wing pattern and showed that light is concentrated between spikes where intensity is enhanced by up to 3- to 4-fold. The closely packed pattern of nanospikes reduces the reflectivity of the wing throughout the visible light spectrum and over a wide range of incident angles, hence acting as an antireflection coating.
The influence of aspect ratio and stroke pattern on force generation of a bat-inspired membrane wing
Swartz, Sharon M.; Breuer, Kenneth S.
2017-01-01
Aspect ratio (AR) is one parameter used to predict the flight performance of a bat species based on wing shape. Bats with high AR wings are thought to have superior lift-to-drag ratios and are therefore predicted to be able to fly faster or to sustain longer flights. By contrast, bats with lower AR wings are usually thought to exhibit higher manoeuvrability. However, the half-span ARs of most bat wings fall into a narrow range of about 2.5–4.5. Furthermore, these predictions do not take into account the wide variation in flapping motion observed in bats. To examine the influence of different stroke patterns, we measured lift and drag of highly compliant membrane wings with different bat-relevant ARs. A two degrees of freedom shoulder joint allowed for independent control of flapping amplitude and wing sweep. We tested five models with the same variations of stroke patterns, flapping frequencies and wind speed velocities. Our results suggest that within the relatively small AR range of bat wings, AR has no clear effect on force generation. Instead, the generation of lift by our simple model mostly depends on wingbeat frequency, flapping amplitude and freestream velocity; drag is mostly affected by the flapping amplitude. PMID:28163875
Subtractive Structural Modification of Morpho Butterfly Wings.
Shen, Qingchen; He, Jiaqing; Ni, Mengtian; Song, Chengyi; Zhou, Lingye; Hu, Hang; Zhang, Ruoxi; Luo, Zhen; Wang, Ge; Tao, Peng; Deng, Tao; Shang, Wen
2015-11-11
Different from studies of butterfly wings through additive modification, this work for the first time studies the property change of butterfly wings through subtractive modification using oxygen plasma etching. The controlled modification of butterfly wings through such subtractive process results in gradual change of the optical properties, and helps the further understanding of structural optimization through natural evolution. The brilliant color of Morpho butterfly wings is originated from the hierarchical nanostructure on the wing scales. Such nanoarchitecture has attracted a lot of research effort, including the study of its optical properties, its potential use in sensing and infrared imaging, and also the use of such structure as template for the fabrication of high-performance photocatalytic materials. The controlled subtractive processes provide a new path to modify such nanoarchitecture and its optical property. Distinct from previous studies on the optical property of the Morpho wing structure, this study provides additional experimental evidence for the origination of the optical property of the natural butterfly wing scales. The study also offers a facile approach to generate new 3D nanostructures using butterfly wings as the templates and may lead to simpler structure models for large-scale man-made structures than those offered by original butterfly wings. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ancient Wings: animating the evolution of butterfly wing patterns.
Arbesman, Samuel; Enthoven, Leo; Monteiro, Antónia
2003-10-01
Character optimization methods can be used to reconstruct ancestral states at the internal nodes of phylogenetic trees. However, seldom are these ancestral states visualized collectively. Ancient Wings is a computer program that provides a novel method of visualizing the evolution of several morphological traits simultaneously. It allows users to visualize how the ventral hindwing pattern of 54 butterflies in the genus Bicyclus may have changed over time. By clicking on each of the nodes within the evolutionary tree, the user can see an animation of how wing size, eyespot size, and eyespot position relative the wing margin, have putatively evolved as a collective whole. Ancient Wings may be used as a pedagogical device as well as a research tool for hypothesis-generation in the fields of evolutionary, ecological, and developmental biology.
Obara, Yoshiaki; Ozawa, Gaku; Fukano, Yuya
2008-11-01
The British and Japanese subspecies of the cabbage butterfly, Pieris rapae , differ in terms of the UV reflectance of their wings ( Obara and Majerus, 2000 ). We studied the biogeographical distribution of the female cabbage butterfly having wings with UV reflectance around the Eurasian continent, and between Britain and Japan. For the study, we collected specimens from various locations. A gradient in the UV reflectance of the wings appears to exist along the west-east axis; reflectance was higher toward the east and reached a peak in butterflies in Japan. The UV-reflecting Japanese subspecies Pieris rapae crucivora was found exclusively along the east coast of the Eurasian continent. This suggests that the Japanese subspecies has evolved from a continental ancestor, with females having UV-absorbing wings. We discuss the results of our study with regard to the evolution and adaptive significance of UV coloration in the Japanese subspecies.
A color video display technique for flow field surveys
NASA Technical Reports Server (NTRS)
Winkelmann, A. E.; Tsao, C. P.
1982-01-01
A computer driven color video display technique has been developed for the presentation of wind tunnel flow field survey data. The results of both qualitative and quantitative flow field surveys can be presented in high spatial resolutions color coded displays. The technique has been used for data obtained with a hot-wire probe, a split-film probe, a Conrad (pitch) probe and a 5-tube pressure probe in surveys above and behind a wing with partially stalled and fully stalled flow.
Pantelić, Dejan; Curčić, Srećko; Savić-Šević, Svetlana; Korać, Aleksandra; Kovačević, Aleksander; Curčić, Božidar; Bokić, Bojana
2011-03-28
The iridescent features of the butterfly species Apatura iris (Linnaeus, 1758) and A. ilia (Denis & Schiffermüller, 1775) were studied. We recognized the structural color of scales only on the dorsal side of both the fore and hind wings of males of both of the aforementioned butterfly species. The scale dimensions and microstructure were analyzed by a scanning electron microscope (SEM) and transmission electron microscope (TEM). The optical properties were measured and it was found that the peak reflectivity is around 380 nm, with a spectral width (full width at half maximum) of approximately 50 nm in both species. The angular selectivity is high and a purple iridescent color is observed within the angular range of only 18 degrees in both species.
Occurrence of Six Honeybee Viruses in Diseased Austrian Apiaries
Berényi, Olga; Bakonyi, Tamás; Derakhshifar, Irmgard; Köglberger, Hemma; Nowotny, Norbert
2006-01-01
The occurrence, prevalence, and distribution patterns of acute bee paralysis virus (ABPV), black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Kashmir bee virus (KBV), and sacbrood virus (SBV) were investigated in 90 Austrian honeybee colonies suffering from symptoms of depopulation, sudden collapse, paralysis, or dark coloring by employing reverse transcription-PCR. Infestation with parasites was also recorded. The samples originated from all parts of Austria. The most prevalent virus was DWV, present in 91% of samples, followed by ABPV, SBV, and BQCV (68%, 49%, and 30%, respectively). CBPV was detected in 10% of colonies, while KBV was not present in any sample. In most samples, more than one virus was identified. The distribution pattern of ABPV, BQCV, CBPV, and SBV varied considerably in the different geographic regions investigated, while DWV was widespread in all Austrian federal states. In bees that showed dark coloring and disorientation, CBPV was always detected. Simultaneous infections of DWV and ABPV were most frequently observed in colonies suffering from weakness, depopulation, and sudden collapse. Bees obtained from apparently healthy colonies within the same apiaries showed a similar distribution pattern of viruses; however, the relative virus load was 10 to 126 times lower than in bees from diseased colonies. A limited number of bee samples from surrounding central European countries (Germany, Poland, Hungary, and Slovenia) were also tested for the presence of the above viruses. Variances were found in the distribution of BQCV and SBV. PMID:16597939
Baxter, S W; Hoffman, J I; Tregenza, T; Wedell, N; Hosken, D J
2017-01-01
Understanding selection in the wild remains a major aim of evolutionary ecology and work by Ford and colleagues on the meadow brown butterfly Maniola jurtina did much to ignite this agenda. A great deal of their work was conducted during the 1950s on the Isles of Scilly. They documented island-specific wing-spot patterns that remained consistent over about a decade, but patterns on some islands changed after environmental perturbation. It was suggested that these wing-spot patterns reflected island-specific selection and that there was little migration between islands. However, genetic studies to test the underlying assumption of restricted migration are lacking and it is also unknown whether the originally described wing-spot patterns have persisted over time. We therefore collected female butterflies from five of Ford's original study locations, including three large islands (St Mary's, St Martin's and Tresco) and two small islands (Tean and St Helen's). Wing-spot patterns had not changed appreciably over time on three of the islands (two large and one small), but were significantly different on the other two. Furthermore, analysis of 176 amplified fragment length polymorphisms revealed significant genome-wide differentiation among the five islands. Our findings are consistent with Ford's conclusions that despite the close proximity of these islands, there is restricted gene flow among them. PMID:27804964
What shapes the continuum of reproductive isolation? Lessons from Heliconius butterflies.
Mérot, C; Salazar, C; Merrill, R M; Jiggins, C D; Joron, M
2017-06-14
The process by which species evolve can be illuminated by investigating barriers that limit gene flow between taxa. Recent radiations, such as Heliconius butterflies, offer the opportunity to compare isolation between pairs of taxa at different stages of ecological, geographical, and phylogenetic divergence. Here, we report a comparative analysis of existing and novel data in order to quantify the strength and direction of isolating barriers within a well-studied clade of Heliconius Our results highlight that increased divergence is associated with the accumulation of stronger and more numerous barriers to gene flow. Wing pattern is both under natural selection for Müllerian mimicry and involved in mate choice, and therefore underlies several isolating barriers. However, pairs which share a similar wing pattern also display strong reproductive isolation mediated by traits other than wing pattern. This suggests that, while wing pattern is a key factor for early stages of divergence, it may become facultative at later stages of divergence. Additional factors including habitat partitioning, hybrid sterility, and chemically mediated mate choice are associated with complete speciation. Therefore, although most previous work has emphasized the role of wing pattern, our comparative results highlight that speciation is a multi-dimensional process, whose completion is stabilized by many factors. © 2017 The Author(s).
Interplay of cell dynamics and epithelial tension during morphogenesis of the Drosophila pupal wing
Etournay, Raphaël; Popović, Marko; Merkel, Matthias; Nandi, Amitabha; Blasse, Corinna; Aigouy, Benoît; Brandl, Holger; Myers, Gene; Salbreux, Guillaume; Jülicher, Frank; Eaton, Suzanne
2015-01-01
How tissue shape emerges from the collective mechanical properties and behavior of individual cells is not understood. We combine experiment and theory to study this problem in the developing wing epithelium of Drosophila. At pupal stages, the wing-hinge contraction contributes to anisotropic tissue flows that reshape the wing blade. Here, we quantitatively account for this wing-blade shape change on the basis of cell divisions, cell rearrangements and cell shape changes. We show that cells both generate and respond to epithelial stresses during this process, and that the nature of this interplay specifies the pattern of junctional network remodeling that changes wing shape. We show that patterned constraints exerted on the tissue by the extracellular matrix are key to force the tissue into the right shape. We present a continuum mechanical model that quantitatively describes the relationship between epithelial stresses and cell dynamics, and how their interplay reshapes the wing. DOI: http://dx.doi.org/10.7554/eLife.07090.001 PMID:26102528
Workshop II On Unsteady Separated Flow Proceedings
1988-07-28
was static stall angle of 12 ° . achieved by injecting diluted food coloring at the apex through a 1.5 mm diameter tube placed The response of the wing...differences with uniform step size in q, and trailing -. 75 three- pront differences with uniform step size in ,, ,,as used The nonlinearity of the...flow prop- "Kutta condition." erties for slender 3D wings are addressed. To begin the The present paper emphasizes recent progress in the de- study
Patterning of a compound eye on an extinct dipteran wing.
Dinwiddie, April; Rachootin, Stan
2011-04-23
We have discovered unexpected similarities between a novel and characteristic wing organ in an extinct biting midge from Baltic amber, Eohelea petrunkevitchi, and the surface of a dipteran's compound eye. Scanning electron microscope images now reveal vestigial mechanoreceptors between the facets of the organ. We interpret Eohelea's wing organ as the blending of these two developmental systems: the formation and patterning of the cuticle in the eye and of the wing. Typically, only females in the genus carry this distinctive, highly organized structure. Two species were studied (E. petrunkevitchi and E. sinuosa), and the structure differs in form between them. We examine Eohelea's wing structures for modes of fabrication, material properties and biological functions, and the effective ecological environment in which these midges lived. We argue that the current view of the wing organ's function in stridulation has been misconstrued since it was described half a century ago.
New neotropical species of Trupanea (Diptera: Tephritidae) with unusual wing patterns
USDA-ARS?s Scientific Manuscript database
Four species of Trupanea (Diptera: Tephritidae) with unusual wing patterns are described from the Neotropical Region: T. dimorphica (Argentina), T. fasciata (Argentina), T. polita (Argentina and Bolivia), and T. trivittata (Argentina). Celidosphenella Hendel, 1914 and Melanotrypana Hering, 1944 are ...
Conservatism and novelty in the genetic architecture of adaptation in Heliconius butterflies.
Huber, B; Whibley, A; Poul, Y L; Navarro, N; Martin, A; Baxter, S; Shah, A; Gilles, B; Wirth, T; McMillan, W O; Joron, M
2015-05-01
Understanding the genetic architecture of adaptive traits has been at the centre of modern evolutionary biology since Fisher; however, evaluating how the genetic architecture of ecologically important traits influences their diversification has been hampered by the scarcity of empirical data. Now, high-throughput genomics facilitates the detailed exploration of variation in the genome-to-phenotype map among closely related taxa. Here, we investigate the evolution of wing pattern diversity in Heliconius, a clade of neotropical butterflies that have undergone an adaptive radiation for wing-pattern mimicry and are influenced by distinct selection regimes. Using crosses between natural wing-pattern variants, we used genome-wide restriction site-associated DNA (RAD) genotyping, traditional linkage mapping and multivariate image analysis to study the evolution of the architecture of adaptive variation in two closely related species: Heliconius hecale and H. ismenius. We implemented a new morphometric procedure for the analysis of whole-wing pattern variation, which allows visualising spatial heatmaps of genotype-to-phenotype association for each quantitative trait locus separately. We used the H. melpomene reference genome to fine-map variation for each major wing-patterning region uncovered, evaluated the role of candidate genes and compared genetic architectures across the genus. Our results show that, although the loci responding to mimicry selection are highly conserved between species, their effect size and phenotypic action vary throughout the clade. Multilocus architecture is ancestral and maintained across species under directional selection, whereas the single-locus (supergene) inheritance controlling polymorphism in H. numata appears to have evolved only once. Nevertheless, the conservatism in the wing-patterning toolkit found throughout the genus does not appear to constrain phenotypic evolution towards local adaptive optima.
Peabody, Nathan C.; Pohl, Jascha B.; Diao, Fengqiu; Vreede, Andrew P.; Sandstrom, David J.; Wang, Howard; Zelensky, Paul K.; White, Benjamin H.
2009-01-01
After emergence, adult flies and other insects select a suitable perch and expand their wings. Wing expansion is governed by the hormone bursicon and can be delayed under adverse environmental conditions. How environmental factors delay bursicon release and alter perch selection and expansion behaviors has not been investigated in detail. Here we provide evidence that in Drosophila the motor programs underlying perch selection and wing expansion have different environmental dependencies. Using physical manipulations, we demonstrate that the decision to perch is based primarily on environmental valuations and is incrementally delayed under conditions of increasing perturbation and confinement. In contrast, the all-or-none motor patterns underlying wing expansion are relatively invariant in length regardless of environmental conditions. Using a novel technique for targeted activation of neurons, we show that the highly stereotyped wing expansion motor patterns can be initiated by stimulation of NCCAP, a small network of central neurons that regulates the release of bursicon. Activation of this network using the cold-sensitive rat TRPM8 channel is sufficient to trigger all essential behavioral and somatic processes required for wing expansion. The delay of wing expansion under adverse circumstances thus couples an environmentally-sensitive decision network to a command-like network that initiates a fixed action pattern. Because NCCAP mediates environmentally-insensitive ecdysis-related behaviors in Drosophila development prior to adult emergence, the study of wing expansion promises insights not only into how networks mediate behavioral choices, but also into how decision networks develop. PMID:19295141
Timmons, Chris; Hassell, Aaron; Lauziere, Isabelle; Bextine, Blake
2011-01-01
A red pigment is contained in the wing veins of the glassy-winged sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae). This insect is the main vector of the plant-pathogenic bacterium Xylella fastidiosa Wells (Xanthomonadales: Xanthomonadaceae), the causal agent of Pierce's disease of grapevines. Over the course of the H. vitripennis lifespan, the red pigment darkens and eventually becomes brown/black in color. These pigments are believed to be pheomelanin and eumelanin, respectively. The age of H. vitripennis can be determined by calculating the amount of red pigment found in the wings by analyzing high resolution wing photographs with image analysis software. In this study, a standard curve for the age determination of H. vitripennis was developed using laboratory-reared insects of known ages varying from 1 to 60 days. The impact of three environmental conditions on these readings was also investigated and found to have little effect on the age determination, and could be easily accounted for. Finally, field collected insects from several Central Texas vineyards were successfully analyzed for age determination suggesting that the annually reported influx of H. vitripennis was composed almost entirely of older insects.
Refractive index dependence of Papilio Ulysses butterfly wings reflectance spectra
NASA Astrophysics Data System (ADS)
Isnaeni, Muslimin, Ahmad Novi; Birowosuto, Muhammad Danang
2016-02-01
We have observed and utilized butterfly wings of Papilio Ulysses for refractive index sensor. We noticed this butterfly wings have photonic crystal structure, which causes blue color appearance on the wings. The photonic crystal structure, which consists of cuticle and air void, is approximated as one dimensional photonic crystal structure. This photonic crystal structure opens potential to several optical devices application, such as refractive index sensor. We have utilized small piece of Papilio Ulysses butterfly wings to characterize refractive index of several liquid base on reflectance spectrum of butterfly wings in the presence of sample liquid. For comparison, we simulated reflectance spectrum of one dimensional photonic crystal structure having material parameter based on real structure of butterfly wings. We found that reflectance spectrum peaks shifted as refractive index of sample changes. Although there is a slight difference in reflectance spectrum peaks between measured spectrum and calculated spectrum, the trend of reflectance spectrum peaks as function of sample's refractive index is the similar. We assume that during the measurement, the air void that filled by sample liquid is expanded due to liquid pressure. This change of void shape causes non-similarity between measured spectrum and calculated spectrum.
Image processing of aerodynamic data
NASA Technical Reports Server (NTRS)
Faulcon, N. D.
1985-01-01
The use of digital image processing techniques in analyzing and evaluating aerodynamic data is discussed. An image processing system that converts images derived from digital data or from transparent film into black and white, full color, or false color pictures is described. Applications to black and white images of a model wing with a NACA 64-210 section in simulated rain and to computed low properties for transonic flow past a NACA 0012 airfoil are presented. Image processing techniques are used to visualize the variations of water film thicknesses on the wing model and to illustrate the contours of computed Mach numbers for the flow past the NACA 0012 airfoil. Since the computed data for the NACA 0012 airfoil are available only at discrete spatial locations, an interpolation method is used to provide values of the Mach number over the entire field.
Roseate Spoonbill displays wings in the Merritt Island National Wildlife Refuge.
NASA Technical Reports Server (NTRS)
2000-01-01
A female roseate spoonbill displays her colorful wings in a mating ritual in Merritt Island National Wildlife Refuge. The birds, named for their brilliant pink color and paddle-shaped bill, feed in shallow water by swinging their bill back and forth, scooping up small fish and crustaceans. They typically inhabit mangroves on the coasts of southern Florida, Louisiana and Texas. The 92,000-acre refuge, which shares a boundary with Kennedy Space Center, is a habitat for more than 330 species of birds, 31 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.
Schöneich, Stefan; Hedwig, Berthold
2012-01-01
The singing behavior of male crickets allows analyzing a central pattern generator (CPG) that was shaped by sexual selection for reliable production of species-specific communication signals. After localizing the essential ganglia for singing in Gryllus bimaculatus, we now studied the calling song CPG at the cellular level. Fictive singing was initiated by pharmacological brain stimulation. The motor pattern underlying syllables and chirps was recorded as alternating spike bursts of wing-opener and wing-closer motoneurons in a truncated wing nerve; it precisely reflected the natural calling song. During fictive singing, we intracellularly recorded and stained interneurons in thoracic and abdominal ganglia and tested their impact on the song pattern by intracellular current injections. We identified three interneurons of the metathoracic and first unfused abdominal ganglion that rhythmically de- and hyperpolarized in phase with the syllable pattern and spiked strictly before the wing-opener motoneurons. Depolarizing current injection in two of these opener interneurons caused additional rhythmic singing activity, which reliably reset the ongoing chirp rhythm. The closely intermeshing arborizations of the singing interneurons revealed the dorsal midline neuropiles of the metathoracic and three most anterior abdominal neuromeres as the anatomical location of singing pattern generation. In the same neuropiles, we also recorded several closer interneurons that rhythmically hyper- and depolarized in the syllable rhythm and spiked strictly before the wing-closer motoneurons. Some of them received pronounced inhibition at the beginning of each chirp. Hyperpolarizing current injection in the dendrite revealed postinhibitory rebound depolarization as one functional mechanism of central pattern generation in singing crickets. PMID:23170234
Interaction of a trailing vortex with an oscillating wing
NASA Astrophysics Data System (ADS)
McKenna, C.; Fishman, G.; Rockwell, D.
2018-01-01
A technique of particle image velocimetry is employed to characterize the flow structure of a trailing vortex incident upon the tip region of an oscillating wing (plate). The amplitude and velocity of the wing are nearly two orders of magnitude smaller than the wing chord and free stream velocity, respectively. Depending upon the outboard displacement of the incident vortex relative to the wing tip, distinctive patterns of upwash, downwash, and shed vorticity are observed. These patterns are a strong function of the phase of the wing motion during its oscillation cycle. At a given phase, the wing oscillation induces upwash that is reinforced by the upwash of the incident vortex, giving a maximum net upwash. Conversely, when these two origins of upwash counteract, rather than reinforce, one another during the oscillation cycle, the net upwash attains minimum value. Analogous interpretations hold for regions of maximum and minimum net downwash located outboard of the regions of upwash. The magnitude and scale of the vorticity shed from the tip of the wing are directly correlated with the net upwash, which takes different forms related to the outboard displacement of the incident vortex. As the location of the incident vortex is displaced towards the wing tip, both the maximum upwash and the maximum vorticity of the tip vortex initially increase and then decrease. For the limiting case where the incident vortex impinges directly upon the tip of the wing, there is no tip vortex or induced region of upwash. Furthermore, at small values of vortex displacement from the wing tip, the position of the incident vortex varies significantly from its nominal position during the oscillation cycle. All of the foregoing features are interpreted in conjunction with the flow topology in the form of streamlines and critical points, superposed on patterns of vorticity. It is shown that despite the small amplitude of the wing motion, the flow topology is fundamentally different at maximum positive and negative values of the velocity of the wing tip, that is, they are not symmetric.
Márk, Géza I; Vértesy, Zofia; Kertész, Krisztián; Bálint, Zsolt; Biró, László P
2009-11-01
In order to study local and global order in butterfly wing scales possessing structural colors, we have developed a direct space algorithm, based on averaging the local environment of the repetitive units building up the structure. The method provides the statistical distribution of the local environments, including the histogram of the nearest-neighbor distance and the number of nearest neighbors. We have analyzed how the different kinds of randomness present in the direct space structure influence the reciprocal space structure. It was found that the Fourier method is useful in the case of a structure randomly deviating from an ordered lattice. The direct space averaging method remains applicable even for structures lacking long-range order. Based on the first Born approximation, a link is established between the reciprocal space image and the optical reflectance spectrum. Results calculated within this framework agree well with measured reflectance spectra because of the small width and moderate refractive index contrast of butterfly scales. By the analysis of the wing scales of Cyanophrys remus and Albulina metallica butterflies, we tested the methods for structures having long-range order, medium-range order, and short-range order.
NASA Astrophysics Data System (ADS)
Márk, Géza I.; Vértesy, Zofia; Kertész, Krisztián; Bálint, Zsolt; Biró, László P.
2009-11-01
In order to study local and global order in butterfly wing scales possessing structural colors, we have developed a direct space algorithm, based on averaging the local environment of the repetitive units building up the structure. The method provides the statistical distribution of the local environments, including the histogram of the nearest-neighbor distance and the number of nearest neighbors. We have analyzed how the different kinds of randomness present in the direct space structure influence the reciprocal space structure. It was found that the Fourier method is useful in the case of a structure randomly deviating from an ordered lattice. The direct space averaging method remains applicable even for structures lacking long-range order. Based on the first Born approximation, a link is established between the reciprocal space image and the optical reflectance spectrum. Results calculated within this framework agree well with measured reflectance spectra because of the small width and moderate refractive index contrast of butterfly scales. By the analysis of the wing scales of Cyanophrys remus and Albulina metallica butterflies, we tested the methods for structures having long-range order, medium-range order, and short-range order.
6. DETAIL OF MASONRY ON SOUTHWEST WING WALL. MASONRY ON ...
6. DETAIL OF MASONRY ON SOUTHWEST WING WALL. MASONRY ON WING WALLS IS LAID IN A RANDOM RUBBLE PATTERN. - Core Creek County Bridge, Spanning Core Creek, approximately 1 mile South of State Route 332 (Newtown Bypass), Newtown, Bucks County, PA
Sweet, Andrew D.; Chesser, R. Terry; Johnson, Kevin P.
2017-01-01
Host–parasite coevolutionary histories can differ among multiple groups of parasites associated with the same group of hosts. For example, parasitic wing and body lice (Insecta: Phthiraptera) of New World pigeons and doves (Aves: Columbidae) differ in their cophylogenetic patterns, with body lice exhibiting higher phylogenetic congruence with their hosts than wing lice. In this study, we focus on the wing and body lice of Australian phabine pigeons and doves to determine whether the patterns in New World pigeons and doves are consistent with those of pigeons and doves from other regions. Using molecular sequence data for most phabine species and their lice, we estimated phylogenetic trees for all three groups (pigeons and doves, wing lice and body lice), and compared the phabine (host) tree with both parasite trees using multiple cophylogenetic methods. We found a pattern opposite to that found for New World pigeons and doves, with Australian wing lice showing congruence with their hosts, and body lice exhibiting a lack of congruence. There are no documented records of hippoboscid flies associated with Australian phabines, thus these lice may lack the opportunity to disperse among host species by attaching to hippoboscid flies (phoresis), which could explain these patterns. However, additional sampling for flies is needed to confirm this hypothesis. Large differences in body size among phabine pigeons and doves may also help to explain the congruence of the wing lice with their hosts. It may be more difficult for wing lice than body lice to switch among hosts that vary more dramatically in size. The results from this study highlight how host–parasite coevolutionary histories can vary by region, and how local factors can shape the relationship.
Sweet, Andrew D; Chesser, R Terry; Johnson, Kevin P
2017-05-01
Host-parasite coevolutionary histories can differ among multiple groups of parasites associated with the same group of hosts. For example, parasitic wing and body lice (Insecta: Phthiraptera) of New World pigeons and doves (Aves: Columbidae) differ in their cophylogenetic patterns, with body lice exhibiting higher phylogenetic congruence with their hosts than wing lice. In this study, we focus on the wing and body lice of Australian phabine pigeons and doves to determine whether the patterns in New World pigeons and doves are consistent with those of pigeons and doves from other regions. Using molecular sequence data for most phabine species and their lice, we estimated phylogenetic trees for all three groups (pigeons and doves, wing lice and body lice), and compared the phabine (host) tree with both parasite trees using multiple cophylogenetic methods. We found a pattern opposite to that found for New World pigeons and doves, with Australian wing lice showing congruence with their hosts, and body lice exhibiting a lack of congruence. There are no documented records of hippoboscid flies associated with Australian phabines, thus these lice may lack the opportunity to disperse among host species by attaching to hippoboscid flies (phoresis), which could explain these patterns. However, additional sampling for flies is needed to confirm this hypothesis. Large differences in body size among phabine pigeons and doves may also help to explain the congruence of the wing lice with their hosts. It may be more difficult for wing lice than body lice to switch among hosts that vary more dramatically in size. The results from this study highlight how host-parasite coevolutionary histories can vary by region, and how local factors can shape the relationship. Copyright © 2017 Australian Society for Parasitology. All rights reserved.
Wu, Jun; Yu, Zhijing; Wang, Tao; Zhuge, Jingchang; Ji, Yue; Xue, Bin
2017-06-01
Airplane wing deformation is an important element of aerodynamic characteristics, structure design, and fatigue analysis for aircraft manufacturing, as well as a main test content of certification regarding flutter for airplanes. This paper presents a novel real-time detection method for wing deformation and flight flutter detection by using three-dimensional speckle image correlation technology. Speckle patterns whose positions are determined through the vibration characteristic of the aircraft are coated on the wing; then the speckle patterns are imaged by CCD cameras which are mounted inside the aircraft cabin. In order to reduce the computation, a matching technique based on Geodetic Systems Incorporated coded points combined with the classical epipolar constraint is proposed, and a displacement vector map for the aircraft wing can be obtained through comparing the coordinates of speckle points before and after deformation. Finally, verification experiments containing static and dynamic tests by using an aircraft wing model demonstrate the accuracy and effectiveness of the proposed method.
Roseate Spoonbill displays wings in the Merritt Island National Wildlife Refuge.
NASA Technical Reports Server (NTRS)
2000-01-01
A female roseate spoonbill (left) displays her colorful wings to the male at right in a mating ritual in Merritt Island National Wildlife Refuge. The birds, named for their brilliant pink color and paddle-shaped bill, feed in shallow water by swinging their bill back and forth, scooping up small fish and crustaceans. They typically inhabit mangroves on the coasts of southern Florida, Louisiana and Texas. The 92,000-acre refuge, which shares a boundary with Kennedy Space Center, is a habitat for more than 330 species of birds, 31 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.
Evolution of antero‐posterior patterning of the limb: Insights from the chick
2017-01-01
Summary The developing limbs of chicken embryos have served as pioneering models for understanding pattern formation for over a century. The ease with which chick wing and leg buds can be experimentally manipulated, while the embryo is still in the egg, has resulted in the discovery of important developmental organisers, and subsequently, the signals that they produce. Sonic hedgehog (Shh) is produced by mesenchyme cells of the polarizing region at the posterior margin of the limb bud and specifies positional values across the antero‐posterior axis (the axis running from the thumb to the little finger). Detailed experimental embryology has revealed the fundamental parameters required to specify antero‐posterior positional values in response to Shh signaling in chick wing and leg buds. In this review, the evolution of the avian wing and leg will be discussed in the broad context of tetrapod paleontology, and more specifically, ancestral theropod dinosaur paleontology. How the parameters that dictate antero‐posterior patterning could have been modulated to produce the avian wing and leg digit patterns will be considered. Finally, broader speculations will be made regarding what the antero‐posterior patterning of chick limbs can tell us about the evolution of other digit patterns, including those that were found in the limbs of the earliest tetrapods. PMID:28734068
Poteat, V Paul; Spanierman, Lisa B
2012-01-01
Among 342 white college students, we examined the effects of social dominance orientation (SDO), right-wing authoritarianism (RWA), and racial color-blindness on modern racism attitudes. Structural equation modeling was used to test the indirect effects of SDO and RWA on modern racism attitudes through color-blind racial attitudes. We found strong indirect effects of SDO and RWA on modern racism through racial color-blindness. We did not find support for an alternative model, in which we tested racial color-blindness as a moderator of the effects of SDO and RWA on modern racism. Findings suggest that highly dominant and authoritarian white students endorse color-blind racial attitudes, although likely for different reasons. In turn, this predicts their modern racism attitudes. These findings indicate racial color-blindness is important to address as part of anti-racism education.
An analysis of aircrew communication patterns and content
NASA Astrophysics Data System (ADS)
Oser, Randall L.; Prince, Carolyn; Morgan, Ben B., Jr.; Simpson, Steven S.
1991-09-01
The findings reported here represent a detailed analysis of tactical rotary-wing aircrew communication patterns and content. This research is part of an extensive effort to investigate the nature of tactical aircrew coordination and to develop effective mission-oriented aircrew coordination training. The primary objectives of this research were to answer the following questions: (1) What specific communication patterns and content are demonstrated by different helicopter crewmembers (i.e., Helicopter Aircraft Commander - HAC and Helicopter 2nd Pilot - H2P)? (2) Do tactical aircrew communication patterns and content vary as a function of the performance demands and requirements of different flight conditions (i.e., routine and non-routine)? (3) Are the communication patterns and content of more effective aircrews different from those of less effective aircrews? (4) What similarities exist between the communication patterns and content of military rotary-wing aircrews and commercial fixed-wing aircrews? and (5) Can the results of the communication analyses have an impact on aircrew coordination training?
Torquato, Libéria Souza; Mattos, Daniel; Matta, Bruna Palma; Bitner-Mathé, Blanche Christine
2014-12-01
Organ shape evolves through cross-generational changes in developmental patterns at cellular and/or tissue levels that ultimately alter tissue dimensions and final adult proportions. Here, we investigated the cellular basis of an artificially selected divergence in the outline shape of Drosophila melanogaster wings, by comparing flies with elongated or rounded wing shapes but with remarkably similar wing sizes. We also tested whether cellular plasticity in response to developmental temperature was altered by such selection. Results show that variation in cellular traits is associated with wing shape differences, and that cell number may play an important role in wing shape response to selection. Regarding the effects of developmental temperature, a size-related plastic response was observed, in that flies reared at 16 °C developed larger wings with larger and more numerous cells across all intervein regions relative to flies reared at 25 °C. Nevertheless, no conclusive indication of altered phenotypic plasticity was found between selection strains for any wing or cellular trait. We also described how cell area is distributed across different intervein regions. It follows that cell area tends to decrease along the anterior wing compartment and increase along the posterior one. Remarkably, such pattern was observed not only in the selected strains but also in the natural baseline population, suggesting that it might be canalized during development and was not altered by the intense program of artificial selection for divergent wing shapes.
Michielsen, K; De Raedt, H; Stavenga, D G
2010-05-06
We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization effects. We briefly discuss the possible biological utility of the green coloration and polarization effects.
Hypothesis testing in evolutionary developmental biology: a case study from insect wings.
Jockusch, E L; Ober, K A
2004-01-01
Developmental data have the potential to give novel insights into morphological evolution. Because developmental data are time-consuming to obtain, support for hypotheses often rests on data from only a few distantly related species. Similarities between these distantly related species are parsimoniously inferred to represent ancestral aspects of development. However, with limited taxon sampling, ancestral similarities in developmental patterning can be difficult to distinguish from similarities that result from convergent co-option of developmental networks, which appears to be common in developmental evolution. Using a case study from insect wings, we discuss how these competing explanations for similarity can be evaluated. Two kinds of developmental data have recently been used to support the hypothesis that insect wings evolved by modification of limb branches that were present in ancestral arthropods. This support rests on the assumption that aspects of wing development in Drosophila, including similarities to crustacean epipod patterning, are ancestral for winged insects. Testing this assumption requires comparisons of wing development in Drosophila and other winged insects. Here we review data that bear on this assumption, including new data on the functions of wingless and decapentaplegic during appendage allocation in the red flour beetle Tribolium castaneum.
X-ray Tomography and Chemical Imaging within Butterfly Wing Scales
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen Jianhua; Lee Yaochang; Tang, M.-T.
2007-01-19
The rainbow like color of butterfly wings is associated with the internal and surface structures of the wing scales. While the photonic structure of the scales is believed to diffract specific lights at different angle, there is no adequate probe directly answering the 3-D structures with sufficient spatial resolution. The NSRRC nano-transmission x-ray microscope (nTXM) with tens nanometers spatial resolution is able to image biological specimens without artifacts usually introduced in sophisticated sample staining processes. With the intrinsic deep penetration of x-rays, the nTXM is capable of nondestructively investigating the internal structures of fragile and soft samples. In this study,more » we imaged the structure of butterfly wing scales in 3-D view with 60 nm spatial resolution. In addition, synchrotron-radiation-based Fourier transform Infrared (FT-IR) microspectroscopy was employed to analyze the chemical components with spatial information of the butterfly wing scales. Based on the infrared spectral images, we suggest that the major components of scale structure were rich in protein and polysaccharide.« less
Ramey, Andrew M.; Poulson, Rebecca L.; González-Reiche, Ana S.; Wilcox, Benjamin R.; Walther, Patrick; Link, Paul; Carter, Deborah L.; Newsome, George M.; Müller, Maria L.; Berghaus, Roy D.; Perez, Daniel R.; Hall, Jeffrey S.; Stallknecht, David E.
2014-01-01
Seasonal dynamics of influenza A viruses (IAVs) are driven by host density and population immunity. Through an analysis of subtypic data for IAVs isolated from Blue-winged Teal (Anas discors), we present evidence for seasonal patterns in the relative abundance of viral subtypes in spring and summer/autumn.
2015-01-01
Geographical patterns in body size have been described across a wide range of species, leading to the development of a series of fundamental biological rules. However, shape variables are less well-described despite having substantial consequences for organism performance. Wing aspect ratio (AR) has been proposed as a key shape parameter that determines function in flying animals, with high AR corresponding to longer, thinner wings that promote high manoeuvrability, low speed flight, and low AR corresponding to shorter, broader wings that promote high efficiency long distance flight. From this principle it might be predicted that populations living in cooler areas would exhibit low AR wings to compensate for reduced muscle efficiency at lower temperatures. I test this hypothesis using the riverine damselfly, Calopteryx maculata, sampled from 34 sites across its range margin in North America. Nine hundred and seven male specimens were captured from across the 34 sites (mean = 26.7 ± 2.9 SE per site), dissected and measured to quantify the area and length of all four wings. Geometric morphometrics were employed to investigate geographical variation in wing shape. The majority of variation in wing shape involved changes in wing aspect ratio, confirmed independently by geometric morphometrics and wing measurements. There was a strong negative relationship between wing aspect ratio and the maximum temperature of the warmest month which varies from west-east in North America, creating a positive relationship with longitude. This pattern suggests that higher aspect ratio may be associated with areas in which greater flight efficiency is required: regions of lower temperatures during the flight season. I discuss my findings in light of research of the functional ecology of wing shape across vertebrate and invertebrate taxa. PMID:26336648
Pirih, Primož; Wilts, Bodo D; Stavenga, Doekele G
2011-10-01
The males of many pierid butterflies have iridescent wings, which presumably function in intraspecific communication. The iridescence is due to nanostructured ridges of the cover scales. We have studied the iridescence in the males of a few members of Coliadinae, Gonepteryx aspasia, G. cleopatra, G. rhamni, and Colias croceus, and in two members of the Colotis group, Hebomoia glaucippe and Colotis regina. Imaging scatterometry demonstrated that the pigmentary colouration is diffuse whereas the structural colouration creates a directional, line-shaped far-field radiation pattern. Angle-dependent reflectance measurements demonstrated that the directional iridescence distinctly varies among closely related species. The species-dependent scale curvature determines the spatial properties of the wing iridescence. Narrow beam illumination of flat scales results in a narrow far-field iridescence pattern, but curved scales produce broadened patterns. The restricted spatial visibility of iridescence presumably plays a role in intraspecific signalling.
Iwata, Masaki; Hiyama, Atsuki; Otaki, Joji M.
2013-01-01
Developmental studies on wing colour patterns have been performed in nymphalid butterflies, but efficient genetic manipulations, including mutagenesis, have not been well established. Here, we have performed mutagenesis experiments in a lycaenid butterfly, the pale grass blue Zizeeria maha, to produce colour-pattern mutants. We fed the P-generation larvae an artificial diet containing the mutagen ethyl methane sulfonate (EMS), and the F1- and F2-generation adults showed various aberrant colour patterns: dorsoventral transformation, anterioposterior background colouration gap, weak contrast, disarrangement of spots, reduction of the size of spots, loss of spots, fusion of spots, and ectopic spots. Among them, the disarrangement, reduction, and loss of spots were likely produced by the coordinated changes of many spots of a single wing around the discal spot in a system-dependent manner, demonstrating the existence of the central symmetry system. The present study revealed multiple genetic regulations for system-dependent and wing-wide colour-pattern determination in lycaenid butterflies. PMID:23917124
Age and sex determination of the Maui Parrotbill
Berlin, Kim E.; Simon, John C.; Pratt, Thane K.; Baker, Paul E.; Kowalsky, James R.
2001-01-01
We determined the best plumage and morphometric variables for ageing and sexing the Maui Parrotbill (Pseudonestor xanthophrys), an endangered Hawaiian honeycreeper found only on east Maui, Hawaii, by examining and measuring 30 museum specimens and 71 live birds captured in mist nets. Juvenal plumage was identified by the presence of pale-tipped wing bars on the middle and greater coverts, grayish olive dorsal plumage, and dingy white underparts and superciliaries. Birds undergoing first prebasic molt retained the juvenal remiges, rectrices, and wing coverts. Birds in first basic plumage possessed juvenal wing bars and a dull juvenal-like plumage. Subsequent molts were complete, and adults lacked wing bars. Adult males had bright yellow plumage on the cheeks, throat, and superciliaries, as did 27% of adult females. All other adult females had less yellow in the underparts. The dorsal plumage of adult females was more variable than adult males and was either yellow-olive like the males or grayish olive. Adult males had longer wing, bill, tail, and tarsometatarsus and greater mass than adult females. Virtually all males and females could be distinguished by wing length. Morphometrics of immature birds were significantly smaller than for adult males. Only immature male wing chord was significantly larger than that of adult females. Although it was difficult to distinguish between immatures and some adult females based on plumage coloration or measurements, a cut-off point of 70.4 mm for wing chord separated 91% of females from 93% of males, regardless of age.
Micro-pixelation and color mixing in biological photonic structures (presentation video)
NASA Astrophysics Data System (ADS)
Bartl, Michael H.; Nagi, Ramneet K.
2014-03-01
The world of insects displays myriad hues of coloration effects produced by elaborate nano-scale architectures built into wings and exoskeleton. For example, we have recently found many weevils possess photonic architectures with cubic lattices. In this talk, we will present high-resolution three-dimensional reconstructions of weevil photonic structures with diamond and gyroid lattices. Moreover, by reconstructing entire scales we found arrays of single-crystalline domains, each oriented such that only selected crystal faces are visible to an observer. This pixel-like arrangement is key to the angle-independent coloration typical of weevils—a strategy that could enable a new generation of coating technologies.
Robbins, Robert K.; Glassberg, Jeffrey
2013-01-01
Abstract We describe Ministrymon janevicroy Glassberg, sp. n., from the United States (Texas). Its wing pattern closely resembles that of the widespread and well-known lycaenid, Ministrymon azia (Hewitson). The new species is distinguished by the structure of its male and female genitalia, by the patterning of the ground color on the basal half of the ventral hindwing surface, and by the color of its eyes. Adults of Ministrymon janevicroy in nature have olive green eyes in contrast to the dark brown/black eyes of Ministrymon azia. Ministrymon janevicroy occurs in dry deciduous forest and scrub from the United States (Texas) to Costa Rica (Guanacaste) with disjunct populations on Curaçao and Isla Margarita (Venezuela). In contrast, Ministrymon azia occurs from the United States to southern Brazil and Chile in both dry and wet lowland habitats. Nomenclaturally, we remove the name Electrostrymon grumus K. Johnson & Kroenlein, 1993, from the synonymy of Ministrymon azia (where it had been listed as a synonym of Ministrymon hernandezi Schwartz & K. Johnson, 1992). We accord priority to Angulopis hernandezi K. Johnson & Kroenlein, 1993 over Electrostrymon grumus K. Johnson & Kroenlein, 1993, syn. n., which currently is placed in Ziegleria K. Johnson, 1993. The English name Vicroy’s Ministreak is proposed for Ministrymon janevicroy. We update biological records of dispersal and caterpillar food plants, previously attributed to Ministrymon azia, in light of the new taxonomy. PMID:23794910
Finite wing aerodynamics with simulated glaze ice
NASA Technical Reports Server (NTRS)
Khodadoust, A.; Bragg, M. B.; Kerho, M.; Wells, S.; Soltani, M. R.
1992-01-01
The effect of a simulated glaze ice accretion on the aerodynamic performance of a three-dimensional wing is studied experimentally. The model used for these tests was a semi-span wing of effective aspect ratio five, mounted from the sidewall of the UIUC subsonic wind tunnel. The model has an NACA 0012 airfoil section on a rectangular, untwisted planform with interchangeable leading edges to allow for testing both the baseline and the iced wing geometry. A three-component sidewall balance was used to measure lift, drag and pitching moment on the clean and iced model. A four-beam two-color fiberoptic laser Doppler velocimeter (LDV) was used to map the flowfield along several spanwise cuts on the model. Preliminary results from LDV scans, which will be the bulk of this paper, are presented following the force balance measurement results. Initial comparison of LDV surveys compare favorably with inviscid theory results and 2D split hot-film measurements near the model surface.
Waterproof and translucent wings at the same time: problems and solutions in butterflies.
Goodwyn, Pablo Perez; Maezono, Yasunori; Hosoda, Naoe; Fujisaki, Kenji
2009-07-01
Although the colour of butterflies attracts the most attention, the waterproofing properties of their wings are also extremely interesting. Most butterfly wings are considered "super-hydrophobic" because the contact angle (CA) with a water drop exceeds 150 degrees. Usually, butterfly wings are covered with strongly overlapping scales; however, in the case of transparent or translucent wings, scale cover is reduced; thus, the hydrophobicity could be affected. Here, we present a comparative analysis of wing hydrophobicity and its dependence on morphology for two species with translucent wings Parantica sita (Nymphalidae) and Parnassius glacialis (Papilionidae). These species have very different life histories: P. sita lives for up to 6 months as an adult and migrates over long distance, whereas P. glacialis lives for less than 1 month and does not migrate. We measured the water CA and analysed wing morphology with scanning electron microscopy and atomic force microscopy. P. sita has super-hydrophobic wing surfaces, with CA > 160 degrees, whereas P. glacialis did not (CA = 100-135 degrees). Specialised scales were found on the translucent portions of P. sita wings. These scales were ovoid and much thinner than common scales, erect at about 30 degrees, and leaving up to 80% of the wing surface uncovered. The underlying bare wing surface had a remarkable pattern of ridges and knobs. P. glacialis also had over 80% of the wing surface uncovered, but the scales were either setae-like or spade-like. The bare surface of the wing had an irregular wavy smooth pattern. We suggest a mode of action that allows this super-hydrophobic effect with an incompletely covered wing surface. The scales bend, but do not collapse, under the pressure of a water droplet, and the elastic recovery of the structure at the borders of the droplet allows a high apparent CA. Thus, P. sita can be translucent without losing its waterproof properties. This characteristic is likely necessary for the long life and migration of this species. This is the first study of some of the effects on the hydrophobicity of translucency through scales' cover reduction in butterfly wings and on the morphology associated with improved waterproofing.
Color filter array pattern identification using variance of color difference image
NASA Astrophysics Data System (ADS)
Shin, Hyun Jun; Jeon, Jong Ju; Eom, Il Kyu
2017-07-01
A color filter array is placed on the image sensor of a digital camera to acquire color images. Each pixel uses only one color, since the image sensor can measure only one color per pixel. Therefore, empty pixels are filled using an interpolation process called demosaicing. The original and the interpolated pixels have different statistical characteristics. If the image is modified by manipulation or forgery, the color filter array pattern is altered. This pattern change can be a clue for image forgery detection. However, most forgery detection algorithms have the disadvantage of assuming the color filter array pattern. We present an identification method of the color filter array pattern. Initially, the local mean is eliminated to remove the background effect. Subsequently, the color difference block is constructed to emphasize the difference between the original pixel and the interpolated pixel. The variance measure of the color difference image is proposed as a means of estimating the color filter array configuration. The experimental results show that the proposed method is effective in identifying the color filter array pattern. Compared with conventional methods, our method provides superior performance.
Van Truong, Tien; Byun, Doyoung; Kim, Min Jun; Yoon, Kwang Joon; Park, Hoon Cheol
2013-09-01
The aim of this work is to provide an insight into the aerodynamic performance of the beetle during takeoff, which has been estimated in previous investigations. We employed a scaled-up electromechanical model flapping wing to measure the aerodynamic forces and the three-dimensional flow structures on the flapping wing. The ground effect on the unsteady forces and flow structures were also characterized. The dynamically scaled wing model could replicate the general stroke pattern of the beetle's hind wing kinematics during takeoff flight. Two wing kinematic models have been studied to examine the influences of wing kinematics on unsteady aerodynamic forces. In the first model, the angle of attack is asymmetric and varies during the translational motion, which is the flapping motion of the beetle's hind wing. In the second model, the angle of attack is constant during the translational motion. The instantaneous aerodynamic forces were measured for four strokes during the beetle's takeoff by the force sensor attached at the wing base. Flow visualization provided a general picture of the evolution of the three-dimensional leading edge vortex (LEV) on the beetle hind wing model. The LEV is stable during each stroke, and increases radically from the root to the tip, forming a leading-edge spiral vortex. The force measurement results show that the vertical force generated by the hind wing is large enough to lift the beetle. For the beetle hind wing kinematics, the total vertical force production increases 18.4% and 8.6% for the first and second strokes, respectively, due to the ground effect. However, for the model with a constant angle of attack during translation, the vertical force is reduced during the first stroke. During the third and fourth strokes, the ground effect is negligible for both wing kinematic patterns. This finding suggests that the beetle's flapping mechanism induces a ground effect that can efficiently lift its body from the ground during takeoff.
Flow Structure and Force Variation with Aspect Ratio for a Two-Degree-of-Freedom Flapping Wing
NASA Astrophysics Data System (ADS)
Burge, Matthew; Favale, James; Ringuette, Matthew
2014-11-01
We investigate experimentally the effect of aspect ratio (AR) on the flow structure and forces of a two-degree-of-freedom flapping wing. Flapping wings are known to produce complex and unsteady vortex loop structures, and the objective is to characterize their variation with AR and how this influences the lift force. Previous results on rotating wings demonstrated that changes in AR significantly affect the three-dimensional flow structure and lift coefficient. This is primarily due to the relatively greater influence of the tip vortex for lower AR. At Reynolds number of order O(103) we test wings of AR = 2-4, values typically found in nature, with simplified planform shapes. The lift force is measured using a submersible transducer at the base of the wing in a glycerin-water mixture. The qualitative, three-dimensional vortex loop structure for different ARs is obtained using multi-color dye flow visualization. Guided by this, quantitative three-component flow information, namely vorticity, the Q-criterion, and circulation, is acquired from stereoscopic particle image velocimetry in key planes. Of interest is how these parameters and the vortex loop topology vary with AR, and their connection to features in the unsteady force signal. This work is supported by the National Science Foundation, Award Number 1336548, supervised by Dr. Dimitrios Papavassiliou.
Morehouse, Nathan I; Vukusic, Peter; Rutowski, Ron
2006-01-01
A small but growing literature indicates that many animal colours are produced by combinations of structural and pigmentary mechanisms. We investigated one such complex colour phenotype: the highly chromatic wing colours of pierid butterflies including oranges, yellows and patterns which appear white to the human eye, but strongly absorb the ultraviolet (UV) wavelengths visible to butterflies. Pierids produce these bright colours using wing scales that contain collections of minute granules. However, to date, no work has directly characterized the molecular composition or optical properties of these granules. We present results that indicate these granules contain pterin pigments. We also find that pterin granules increase light reflection from single wing scales, such that wing scales containing denser granule arrays reflect more light than those with less dense granule collections. As male wing scales contain more pterin granules than those of females, the sexual dichromatism found in many pierid species can be explained by differences in wing scale pterin deposition. Additionally, the colour pattern elements produced by these pterins are known to be important during mating interactions in a number of pierid species. Therefore, we discuss the potential relevance of our results within the framework of sexual selection and colour signal evolution. PMID:17164199
Decapentaplegic and growth control in the developing Drosophila wing.
Akiyama, Takuya; Gibson, Matthew C
2015-11-19
As a central model for morphogen action during animal development, the bone morphogenetic protein 2/4 (BMP2/4)-like ligand Decapentaplegic (Dpp) is proposed to form a long-range signalling gradient that directs both growth and pattern formation during Drosophila wing disc development. While the patterning role of Dpp secreted from a stripe of cells along the anterior-posterior compartmental boundary is well established, the mechanism by which a Dpp gradient directs uniform cell proliferation remains controversial and poorly understood. Here, to determine the precise spatiotemporal requirements for Dpp during wing disc development, we use CRISPR-Cas9-mediated genome editing to generate a flippase recognition target (FRT)-dependent conditional null allele. By genetically removing Dpp from its endogenous stripe domain, we confirm the requirement of Dpp for the activation of a downstream phospho-Mothers against dpp (p-Mad) gradient and the regulation of the patterning targets spalt (sal), optomotor blind (omb; also known as bifid) and brinker (brk). Surprisingly, however, third-instar wing blade primordia devoid of compartmental dpp expression maintain relatively normal rates of cell proliferation and exhibit only mild defects in growth. These results indicate that during the latter half of larval development, the Dpp morphogen gradient emanating from the anterior-posterior compartment boundary is not directly required for wing disc growth.
Verovnik, Rudi; Wiemers, Martin
2016-01-01
Abstract The Palaearctic Grayling genus Pseudochazara encompasses a number of petrophilous butterfly species, most of which are local endemics especially in their centre of radiation in SW Asia and the Balkans. Due to a lack of consistent morphological characters, coupled with habitat induced variability, their taxonomy is poorly understood and species delimitation is hampered. We employed a DNA barcoding approach to address the question of separate species status for several European taxa and provide first insight into the phylogeny of the genus. Unexpectedly we found conflicting patterns with deep divergences between presumably conspecific taxa and lack of divergence among well-defined species. We propose separate species status for Pseudochazara tisiphone, Pseudochazara amalthea, Pseudochazara amymone, and Pseudochazara kermana all of which have separate well supported clades, with the majority of them becoming local endemics. Lack of resolution in the ‘Mamurra’ species group with well-defined species (in terms of wing pattern and coloration) such as Pseudochazara geyeri, Pseudochazara daghestana and Pseudochazara alpina should be further explored using nuclear molecular markers with higher genetic resolution. PMID:27408604
Michielsen, K.; De Raedt, H.; Stavenga, D. G.
2010-01-01
We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization effects. We briefly discuss the possible biological utility of the green coloration and polarization effects. PMID:19828506
NASA Astrophysics Data System (ADS)
Fukai, Hironobu; Mitsukura, Yasue
We propose a new design support system that can color illustrations according to a person's color preferences that are determined on the basis of the color patterns of illustrations prepared by that person. Recently, many design tools for promoting free design have been developed. However, preferences for various colors differ depending on individual personality. Therefore, a system that can automatically color various designs on the basis of human preference is required. In this study, we propose an automatic modeling system that can be used to model illustrations. To verify the effectiveness of the proposed system, we simulate a coloring design experiment to determine the color patterns preferred by some subjects by using various design data. By using the design data, we determine each subjects preferred color pattern, and send feedback on these individual color patterns to the proposed system.
Butler, Michael W; Leppert, Lynda L; Dufty, Alfred M
2010-01-01
Stressors encountered during avian development may affect an individual's phenotype, including immunocompetence, growth, and feather quality. We examined effects of simulated chronic low-level stress on American kestrel (Falco sparverius) nestlings. Continuous release of corticosterone, a hormone involved in the stress response, can model chronic stress in birds. We implanted 13-d-old males with either corticosterone-filled implants or shams and measured their growth, immune function, and feather coloration. We found no significant differences between groups at the end of the weeklong exposure period in morphometrics (mass, tarsus, wing length, and asymmetry), immunocompetence (cutaneous immunity, heterophil/lymphocyte ratio, and humoral immunity), or feather coloration. One week subsequent to implant removal, however, differences were detected. Sham-implanted birds had significantly longer wings and a reduced level of cutaneous immune function compared with those of birds given corticosterone-filled implants. Therefore, increases of only 2 ng/mL in basal corticosterone titer can have small but measurable effects on subsequent avian development.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-10
... 1993, p. 134). Wings of males are blue above (dorsally), with a narrow black outer border and white... Krizek 1984, p. 112). Seasonal wing pattern variation may be caused by changes in humidity, temperature... the wings (Minno and Emmel 1994, p. 647). The Miami blue can be distinguished from the ceraunus blue...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-06
.... 134). Wings of males are blue above (dorsally), with a narrow black outer border and white fringes... Krizek 1984, p. 112). Seasonal wing pattern variation may be caused by changes in humidity, temperature... on the undersides of the wings (Minno and Emmel 1994, p. 647). The Miami blue can be distinguished...
Flow Modulation and Force Control of Flapping Wings
2014-10-29
evolution of which reflect the wing morphology and kinematics. While the near-wake vortex system directly reflects the action of the wing on the...at 8 different stroke positions, which demonstrate the evolution of the vortex wake structure. The contour plot of Z vorticity at X-Y plane (Z...20 Figure 14. Smoke patterns showing the evolution of the flow structure in an
Beneficial aerodynamic effect of wing scales on the climbing flight of butterflies.
Slegers, Nathan; Heilman, Michael; Cranford, Jacob; Lang, Amy; Yoder, John; Habegger, Maria Laura
2017-01-30
It is hypothesized that butterfly wing scale geometry and surface patterning may function to improve aerodynamic efficiency. In order to investigate this hypothesis, a method to measure butterfly flapping kinematics optically over long uninhibited flapping sequences was developed. Statistical results for the climbing flight flapping kinematics of 11 butterflies, based on a total of 236 individual flights, both with and without their wing scales, are presented. Results show, that for each of the 11 butterflies, the mean climbing efficiency decreased after scales were removed. Data was reduced to a single set of differences of climbing efficiency using are paired t-test. Results show a mean decrease in climbing efficiency of 32.2% occurred with a 95% confidence interval of 45.6%-18.8%. Similar analysis showed that the flapping amplitude decreased by 7% while the flapping frequency did not show a significant difference. Results provide strong evidence that butterfly wing scale geometry and surface patterning improve butterfly climbing efficiency. The authors hypothesize that the wing scale's effect in measured climbing efficiency may be due to an improved aerodynamic efficiency of the butterfly and could similarly be used on flapping wing micro air vehicles to potentially achieve similar gains in efficiency.
NASA Technical Reports Server (NTRS)
Razak, K.
1980-01-01
The question of the effect of distribution and magnitude of spanwise circulation and shed vorticity from an airplane wing on the distribution pattern of agricultural products distributed from an airplane was studied. The first step in an analysis of this question is the determination of the actual distribution of lift along an airplane wing, from which the pattern of shed vorticity can be determined. A procedure is developed to calculate the span loading for flapped and unflapped wings of arbitrary aspect ratio and taper ratio. The procedure was programmed on a small programmable calculator, the Hewlett Packard HP-97, and also was programmed in BASIC language. They could be used to explore the variations in span loading that can be secured by variable flap deflections or the effect of flying at varying air speeds at different airplane gross weights. Either an absolute evaluation of span loading can be secured or comparative span loading can be evaluated to determine their effect on swath width and swath distribution pattern. The programs are intended to assist the user in evaluating the effect of a given spanload distribution.
Observation of the wing deformation and the CFD study of cicada
NASA Astrophysics Data System (ADS)
Dai, Hu; Mohd Adam Das, Shahrizan; Luo, Haoxiang
2011-11-01
We studied the wing properties and kinematics of cicada when the 13-year species emerged in amazingly large numbers in middle Tennessee during May 2011. Using a high-speed camera, we recorded the wing motion of the insect and then reconstructed the three-dimensional wing kinematics using a video digitization software. Like many other insects, the deformation of the cicada wing is asymmetric between the downstroke and upstroke half cycles, and this particular deformation pattern would benefit production of the lift and propulsive forces. Both two-dimensional and three-dimensional CFD studies are carried out based on the reconstructed wing motion. The implication of the study on the role of the aerodynamic force in the wing deformation will be discussed. This work is sponsored by the NSF.
Harbison, Christopher W.; Clayton, Dale H.
2011-01-01
Reciprocal selective effects between coevolving species are often influenced by interactions with the broader ecological community. Community-level interactions may also influence macroevolutionary patterns of coevolution, such as cospeciation, but this hypothesis has received little attention. We studied two groups of ecologically similar feather lice (Phthiraptera: Ischnocera) that differ in their patterns of association with a single group of hosts. The two groups, “body lice” and “wing lice,” are both parasites of pigeons and doves (Columbiformes). Body lice are more host-specific and show greater population genetic structure than wing lice. The macroevolutionary history of body lice also parallels that of their columbiform hosts more closely than does the evolutionary history of wing lice. The closer association of body lice with hosts, compared with wing lice, can be explained if body lice are less capable of switching hosts than wing lice. Wing lice sometimes disperse phoretically on parasitic flies (Diptera: Hippoboscidae), but body lice seldom engage in this behavior. We tested the hypothesis that wing lice switch host species more often than body lice, and that the difference is governed by phoresis. Our results show that, where flies are present, wing lice switch to novel host species in sufficient numbers to establish viable populations on the new host. Body lice do not switch hosts, even where flies are present. Thus, differences in the coevolutionary history of wing and body lice can be explained by differences in host-switching, mediated by a member of the broader parasite community. PMID:21606369
An experimental investigation of the subcritical and supercritical flow about a swept semispan wing
NASA Technical Reports Server (NTRS)
Lockman, W. K.; Seegmiller, H. L.
1983-01-01
An experimental investigation of the turbulent, subcritical and supercritical flow over a swept, semispan wing in a solid wall wind tunnel is described. The program was conducted over a range of Mach numbers, Reynolds numbers, and angles of attack to provide a variety of test cases for assessment of wing computer codes and tunnel wall interference effects. Wing flows both without and with three dimensional flow separation are included. Data include mean surface pressures for both the wing and tunnel walls; surface oil flow patterns on the wing; and mean velocity, flow field surveys. The results are given in tabular form and presented graphically to illustrate some of the effects of the test parameters. Comparisons of the wing pressure data with the results from two inviscid wing codes are also shown to assess the importance of viscous flow and tunnel wall effects.
Multiple scaled disorder in the photonic structure of Morpho rhetenor butterfly
NASA Astrophysics Data System (ADS)
Boulenguez, J.; Berthier, S.; Leroy, F.
2012-03-01
The iridescence of Morpho rhetenor butterfly is known to result from a photonic structure on wing scales, where multilayer interference and grating diffraction occur simultaneously. We characterize the disorder at the photonic structure length scale and at the butterfly scale. We measure the scattering pattern of the wing. Through RCWA and 1st Born approximation models, we link the different disorders to different features in the scattering patterns.
Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics
Iwasaki, Nicole A.; Elzinga, Michael J.; Melis, Johan M.; Dickinson, Michael H.
2017-01-01
Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage. PMID:28163885
Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics.
Muijres, Florian T; Iwasaki, Nicole A; Elzinga, Michael J; Melis, Johan M; Dickinson, Michael H
2017-02-06
Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.
4D metrology of flapping-wing micro air vehicle based on fringe projection
NASA Astrophysics Data System (ADS)
Zhang, Qican; Huang, Lei; Chin, Yao-Wei; Keong, Lau-Gih; Asundi, Anand
2013-06-01
Inspired by dominant flight of the natural flyers and driven by civilian and military purposes, micro air vehicle (MAV) has been developed so far by passive wing control but still pales in aerodynamic performance. Better understanding of flapping wing flight mechanism is eager to improve MAV's flight performance. In this paper, a simple and effective 4D metrology technique to measure full-field deformation of flapping membrane wing is presented. Based on fringe projection and 3D Fourier analysis, the fast and complex dynamic deformation, including wing rotation and wing stroke, of a flapping wing during its flight can be accurately reconstructed from the deformed fringe patterns recorded by a highspeed camera. An experiment was carried on a flapping-wing MAV with 5-cm span membrane wing beating at 30 Hz, and the results show that this method is effective and will be useful to the aerodynamicist or micro aircraft designer for visualizing high-speed complex wing deformation and consequently aid the design of flapping wing mechanism to enhanced aerodynamic performance.
Reed, Robert D; McMillan, W Owen; Nagy, Lisa M
2008-01-07
Geographical variation in the mimetic wing patterns of the butterfly Heliconius erato is a textbook example of adaptive polymorphism; however, little is known about how this variation is controlled developmentally. Using microarrays and qPCR, we identified and compared expression of candidate genes potentially involved with a red/yellow forewing band polymorphism in H. erato. We found that transcripts encoding the pigment synthesis enzymes cinnabar and vermilion showed pattern- and polymorphism-related expression patterns, respectively. cinnabar expression was associated with the forewing band regardless of pigment colour, providing the first gene expression pattern known to be correlated with a major Heliconius colour pattern. In contrast, vermilion expression changed spatially over time in red-banded butterflies, but was not expressed at detectable levels in yellow-banded butterflies, suggesting that regulation of this gene may be involved with the red/yellow polymorphism. Furthermore, we found that the yellow pigment, 3-hydroxykynurenine, is incorporated into wing scales from the haemolymph rather than being synthesized in situ. We propose that some aspects of Heliconius colour patterns are determined by spatio-temporal overlap of pigment gene transcription prepatterns and speculate that evolutionary changes in vermilion regulation may in part underlie an adaptive colour pattern polymorphism.
A preliminary investigation of bird classification by Doppler radar
NASA Technical Reports Server (NTRS)
Martinson, L. W.
1973-01-01
A preliminary study of the application of Doppler radar to the classification of birds is reported. The desirability for improvements in bird classification stems primarily from the hazards they present to jet aircraft in flight and in the vicinity of airports. A secondary need exists in the study of bird migration. The wing body and tail motion of a bird in flight reflect signals which, when analyzed properly present a signature of wing beat pattern which is unique for each bird species. Although the results of this investigation did not validate the feasibility of classifying bird species, they do indicate that a more thorough investigation is warranted. Certain gross characteristics such as wing beat rates, multiple bird patterns, and bird maneuverability, were indicated clearly in the results. Large birds with slow wing beat rates appear to be the most optimum subject for further study with the X-band Doppler radar used in this investigation.
18 CFR 375.103 - Official seal.
Code of Federal Regulations, 2010 CFR
2010-04-01
... protruding from a solid color wing-like shape. Below the eagle shall appear five squares, arranged in a horizontal line. Each of these squares shall contain a circle representing an area of the Commission's responsibility. The first square at the left of the line shall include a stylized representation of a pipeline...
18 CFR 375.103 - Official seal.
Code of Federal Regulations, 2012 CFR
2012-04-01
... protruding from a solid color wing-like shape. Below the eagle shall appear five squares, arranged in a horizontal line. Each of these squares shall contain a circle representing an area of the Commission's responsibility. The first square at the left of the line shall include a stylized representation of a pipeline...
18 CFR 375.103 - Official seal.
Code of Federal Regulations, 2011 CFR
2011-04-01
... protruding from a solid color wing-like shape. Below the eagle shall appear five squares, arranged in a horizontal line. Each of these squares shall contain a circle representing an area of the Commission's responsibility. The first square at the left of the line shall include a stylized representation of a pipeline...
18 CFR 375.103 - Official seal.
Code of Federal Regulations, 2014 CFR
2014-04-01
... protruding from a solid color wing-like shape. Below the eagle shall appear five squares, arranged in a horizontal line. Each of these squares shall contain a circle representing an area of the Commission's responsibility. The first square at the left of the line shall include a stylized representation of a pipeline...
18 CFR 375.103 - Official seal.
Code of Federal Regulations, 2013 CFR
2013-04-01
... protruding from a solid color wing-like shape. Below the eagle shall appear five squares, arranged in a horizontal line. Each of these squares shall contain a circle representing an area of the Commission's responsibility. The first square at the left of the line shall include a stylized representation of a pipeline...
Control of Flow Structure on Low Swept Delta Wing with Steady Leading Edge Blowing
NASA Astrophysics Data System (ADS)
Ozturk, Ilhan; Zharfa, Mohammadreza; Yavuz, Mehmet Metin
2014-11-01
Interest in unmanned combat air vehicles (UCAVs) and micro air vehicles (MAVs) has stimulated investigation of the flow structure, as well as its control, on delta wings having low and moderate values of sweep angle. In the present study, the flow structure is characterized on a delta wing of low sweep 35-degree angle, which is subjected to steady leading edge blowing. The techniques of laser illuminated smoke visualization, laser Doppler anemometry (LDA), and surface pressure measurements are employed to investigate the steady and unsteady nature of the flow structure on delta wing, in relation to the dimensionless magnitude of the blowing coefficient. Using statistics and spectral analysis, unsteadiness of the flow structure is studied in detail. Different injection locations are utilized to apply different blowing patterns in order to identify the most efficient control, which provides the upmost change in the flow structure with the minimum energy input. The study aims to find the optimum flow control strategy to delay or to prevent the stall and possibly to reduce the buffeting on the wing surface. Since the blowing set-up is computer controlled, the unsteady blowing patterns compared to the present steady blowing patterns will be studied next. This project was supported by the Scientific and Technological Research Council of Turkey (Project Number: 3501 111M732).
Distribution and migration of races of the mourning dove
Aldrich, J.W.; Duvall, A.J.
1958-01-01
The Mourning Dove is a widespread species breeding in the non-boreal regions of North and Middle America and from the West Indies south to Panama. It is hunted extensively in many sections of the United States and in some sections of Canada, the West Indies, and Mexico....The trends in geographic variation of Mourning Doves are from dark coloration in the east to pale coloration in the west and from shorter wing length in tropical areas to longer in the temperate region. More rusty underparts are associated with birds of the West Indies, and extremely saturated coloration and relatively large bills and feet have been developed by the population on Clarion Island off the western coast of Mexico. The combinations of geographic variation result in the recognition of five geographic races, two of which breed on the mainland of North America. The race carolinensis of eastern United States can be distinguished from the western race, marginella, by the color of the wings alone, which makes possible the recognition of these racial components from the wings of doves taken from hunters? bags.....Taking Ridgway?s account in ?Birds of North and Middle America? as a basis, discrepancies in the descriptions of sex and racial characters are pointed out. Two races recognized by Ridgway and one suggested as possibly distinct were not substantiated. The occurrence of dark and pale types among the West Indian populations are considered of possible racial significance, but sufficient breeding material is lacking to study the problem satisfactorily.....The allocation of type specimens and names to the various recognizable races which appears in the most recent literature is considered satisfactory. The ecological boundaries between tropical and temperate life zones and between the western grasslands and eastern deciduous forest zones, generally speaking, separate distinct races from each other.....There is an extensive postbreeding wandering of birds in all directions, particularly northward, and there is an extensive mingling of racial types during migration. Concentrations of fall migrants occur in certain areas in the southwestern states and both east and west of the Gulf of Mexico.
Baier, David B; Gatesy, Stephen M; Dial, Kenneth P
2013-01-01
Past studies have shown that birds use their wings not only for flight, but also when ascending steep inclines. Uphill flap-running or wing-assisted incline running (WAIR) is used by both flight-incapable fledglings and flight-capable adults to retreat to an elevated refuge. Despite the broadly varying direction of travel during WAIR, level, and descending flight, recent studies have found that the basic wing path remains relatively invariant with reference to gravity. If so, joints undergo disparate motions to maintain a consistent wing path during those specific flapping modes. The underlying skeletal motions, however, are masked by feathers and skin. To improve our understanding of the form-functional relationship of the skeletal apparatus and joint morphology with a corresponding locomotor behavior, we used XROMM (X-ray Reconstruction of Moving Morphology) to quantify 3-D skeletal kinematics in chukars (Alectoris chukar) during WAIR (ascending with legs and wings) and ascending flight (AF, ascending with wings only) along comparable trajectories. Evidence here from the wing joints demonstrates that the glenohumeral joint controls the vast majority of wing movements. More distal joints are primarily involved in modifying wing shape. All bones are in relatively similar orientations at the top of upstroke during both behaviors, but then diverge through downstroke. Total excursion of the wing is much smaller during WAIR and the tip of the manus follows a more vertical path. The WAIR stroke appears "truncated" relative to ascending flight, primarily stemming from ca. 50% reduction in humeral depression. Additionally, the elbow and wrist exhibit reduced ranges of angular excursions during WAIR. The glenohumeral joint moves in a pattern congruent with being constrained by the acrocoracohumeral ligament. Finally, we found pronounced lateral bending of the furcula during the wingbeat cycle during ascending flight only, though the phasic pattern in chukars is opposite of that observed in starlings (Sturnus vulgaris).
Color relations increase the capacity of visual short-term memory.
Sanocki, Thomas; Sulman, Noah
2011-01-01
Do color relations such as similarity or harmony influence the ease with which colored patterns can be perceived and held in mind? We tested the influence of a relation supported in research on color harmony--similarity of hue--on the capacity of visual short-term memory (VSTM) for colors in patterns. Palettes of 4 similar-hue colors were rated as more pleasant (harmonious) than dissimilar-color palettes. The palettes were used in a VSTM color task. Patterns of 9 to 15 colored squares were presented, and accuracy of color change detection was measured. Memory performance was higher overall for similar-color palettes than for dissimilar-color palettes (experiments 1 and 3). Is this due to color similarity per se, or due to the harmony between colors in similar palettes? A final experiment provided strong support for the importance of color similarity as opposed to harmony. Overall, the advantages for color similarity, in terms of number of color squares held in memory (memory capacity) were 26% to 45% over dissimilar colors. The results indicate that color relations can have a strong impact on the capacity for perceiving and retaining color patterns.
Stella, David; Pecháček, Pavel; Meyer-Rochow, Victor Benno; Kleisner, Karel
2018-06-01
The subject of our investigation was the visual features of wing color with special focus on the UV reflectance in the green-veined white butterfly (Pieris napi). Previous studies had concluded that UV reflectance on dorsal wing surfaces is found only in the female P. napi. Based on UV sensitive photography, we analyzed a correlation between 12 geographic and environmental factors and UV reflectance patterns on 3 patches on the forewings of 407 P. napi specimens from the Palaearctic region. Results had shown that females significantly differ from males: they exhibit a 25% higher UV reflectance. To investigate whether and how UV reflectance levels on the forewings and hindwings of both sexes are influenced by the environment, we performed a principal component analysis (PCA) with several environmental variables. For several variables (in particular, latitude and longitude, mean annual temperature and precipitation, and temperature annual range and altitude), the generalized linear model (GLM) model revealed a significant correlation in both sexes. This suggests a link between UV reflectance levels and the environment and distribution of P. napi. We found that stronger UV reflectance is associated with generally more hostile environments and concluded that large-scale environmental factors influence the UV reflectance on the forewings of both male and female green-veined white butterflies. © 2016 Institute of Zoology, Chinese Academy of Sciences.
Modeling apparent color for visual evaluation of camouflage fabrics
NASA Astrophysics Data System (ADS)
Ramsey, S.; Mayo, T.; Shabaev, A.; Lambrakos, S. G.
2017-08-01
As the U.S. Navy, Army, and Special Operations Forces progress towards fielding more advanced uniforms with multi-colored and highly detailed camouflage patterning, additional test methodologies are necessary in evaluating color in these types of camouflage textiles. The apparent color is the combination of all visible wavelengths (380-760 nm) of light reflected from large (>=1m2 ) fabric sample sizes for a given standoff distance (10-25ft). Camouflage patterns lose resolution with increasing standoff distance, and eventually all colors within the pattern appear monotone (the "apparent color" of the pattern). This paper presents an apparent color prediction model that can be used for evaluation of camouflage fabrics.
Pegram, Kimberly V; Nahm, Alexandra C; Rutowski, Ronald L
2013-01-01
Predation on distasteful animals should favor warning coloration that is relatively conspicuous and phenotypically invariable. However, even among similarly colored individuals there can be variation in their warning signals. In butterflies, individual differences in larval feeding history could cause this variation. The warning signal of the pipevine swallowtail butterfly, Battus philenor L. (Lepidoptera: Papilionidae) consists of both a blue iridescent patch and pigmentbased orange spots on the ventral hindwing. B. philenor males also display a dorsal surface iridescent patch that functions as a sexual indicator signal. A previous study of iridescence in B. philenor found that the iridescent blue on both the dorsal and ventral hind wings is variable and significantly different between lab-reared and field-caught individuals. These differences could be the result of larval food deprivation in the field. Through experimental manipulation of larval diet, larval food deprivation was evaluated as a potential cause of the differences observed between lab and field individuals, and if food deprivation is a source of inter-individual variation in warning signals. B. philenor larvae were food restricted starting at two points in the last larval instar, and one group was fed through pupation. Adult coloration was then compared. Food deprivation led to poorer adult condition, as indicated by lower adult body mass, forewing length, and fat content of stressed individuals. As the level of food deprivation increased, the hue of the iridescent patches on both the dorsal and ventral hind wing shifted to shorter wavelengths, and the chroma of the orange spots decreased. The shifts in iridescent color did not match the differences previously found between lab and field individuals. However, the treatment differences indicate that food deprivation may be a significant source of warning color variation. The differences between the treatment groups are likely detectable by predators, but the effect of the variation on signal effectiveness and function remains to be empirically explored.
Pyrowolakis, George; Bergmann, Sven; Affolter, Markus
2011-01-01
The wing of the fruit fly, Drosophila melanogaster, with its simple, two-dimensional structure, is a model organ well suited for a systems biology approach. The wing arises from an epithelial sac referred to as the wing imaginal disc, which undergoes a phase of massive growth and concomitant patterning during larval stages. The Decapentaplegic (Dpp) morphogen plays a central role in wing formation with its ability to co-coordinately regulate patterning and growth. Here, we asked whether the Dpp signaling activity scales, i.e. expands proportionally, with the growing wing imaginal disc. Using new methods for spatial and temporal quantification of Dpp activity and its scaling properties, we found that the Dpp response scales with the size of the growing tissue. Notably, scaling is not perfect at all positions in the field and the scaling of target gene domains is ensured specifically where they define vein positions. We also found that the target gene domains are not defined at constant concentration thresholds of the downstream Dpp activity gradients P-Mad and Brinker. Most interestingly, Pentagone, an important secreted feedback regulator of the pathway, plays a central role in scaling and acts as an expander of the Dpp gradient during disc growth. PMID:22039350
Flow Structure on a Flapping Wing: Quasi-Steady Limit
NASA Astrophysics Data System (ADS)
Ozen, Cem; Rockwell, Donald
2011-11-01
The flapping motion of an insect wing typically involves quasi-steady motion between extremes of unsteady motion. This investigation characterizes the flow structure for the quasi-steady limit via a rotating wing in the form of a thin rectangular plate having a low aspect ratio (AR =1). Particle Image Velocimetry (PIV) is employed, in order to gain insight into the effects of centripetal and Coriolis forces. Vorticity, velocity and streamline patterns are used to describe the overall flow structure with an emphasis on the leading-edge vortex. A stable leading-edge vortex is maintained over effective angles of attack from 30° to 75° and it is observed that at each angle of attack the flow structure remains relatively same over the Reynolds number range from 3,600 to 14,500. The dimensionless circulation of the leading edge vortex is found to be proportional to the effective angle of attack. Quasi-three-dimensional construction of the flow structure is used to identify the different regimes along the span of the wing which is then complemented by patterns on cross flow planes to demonstrate the influence of root and tip swirls on the spanwise flow. The rotating wing results are also compared with the equivalent of translating wing to further illustrate the effects of the rotation.
Differential involvement of Hedgehog signaling in butterfly wing and eyespot development.
Tong, Xiaoling; Lindemann, Anna; Monteiro, Antónia
2012-01-01
Butterfly eyespots may have evolved from the recruitment of pre-existent gene circuits or regulatory networks into novel locations on the wing. Gene expression data suggests one such circuit, the Hedgehog (Hh) signaling pathway and its target gene engrailed (en), was recruited from a role in patterning the anterior-posterior insect wing axis to a role patterning butterfly eyespots. However, while Junonia coenia expresses hh and en both in the posterior compartment of the wing and in eyespot centers, Bicyclus anynana lacks hh eyespot-specific expression. This suggests that Hh signaling may not be functioning in eyespot development in either species or that it functions in J. coenia but not in B. anynana. In order to test these hypotheses, we performed functional tests of Hh signaling in these species. We investigated the effects of Hh protein sequestration during the larval stage on en expression levels, and on wing size and eyespot size in adults. Hh sequestration led to significantly reduced en expression and to significantly smaller wings and eyespots in both species. But while eyespot size in B. anynana was reduced proportionately to wing size, in J. coenia, eyespots were reduced disproportionately, indicating an independent role of Hh signaling in eyespot development in J. coenia. We conclude that while Hh signaling retains a conserved role in promoting wing growth across nymphalid butterflies, it plays an additional role in eyespot development in some, but not all, lineages of nymphalid butterflies. We discuss our findings in the context of alternative evolutionary scenarios that led to the differential expression of hh and other Hh pathway signaling members across nymphalid species.
Artificial insect wings of diverse morphology for flapping-wing micro air vehicles.
Shang, J K; Combes, S A; Finio, B M; Wood, R J
2009-09-01
The development of flapping-wing micro air vehicles (MAVs) demands a systematic exploration of the available design space to identify ways in which the unsteady mechanisms governing flapping-wing flight can best be utilized for producing optimal thrust or maneuverability. Mimicking the wing kinematics of biological flight requires examining the potential effects of wing morphology on flight performance, as wings may be specially adapted for flapping flight. For example, insect wings passively deform during flight, leading to instantaneous and potentially unpredictable changes in aerodynamic behavior. Previous studies have postulated various explanations for insect wing complexity, but there lacks a systematic approach for experimentally examining the functional significance of components of wing morphology, and for determining whether or not natural design principles can or should be used for MAVs. In this work, a novel fabrication process to create centimeter-scale wings of great complexity is introduced; via this process, a wing can be fabricated with a large range of desired mechanical and geometric characteristics. We demonstrate the versatility of the process through the creation of planar, insect-like wings with biomimetic venation patterns that approximate the mechanical properties of their natural counterparts under static loads. This process will provide a platform for studies investigating the effects of wing morphology on flight dynamics, which may lead to the design of highly maneuverable and efficient MAVs and insight into the functional morphology of natural wings.
Quinn, M.J.; French, J.B.; McNabb, F.M.A.; Ottinger, M.A.
2002-01-01
The purpose of this experiment was to determine the effects of Aroclor 1242, a mixture of polychlorinated biphenyls (PCBs), on plumage characteristics and molt in the American kestrel, Falco sparverills. Several characteristics of plumage. including color and molt schedule, are modulated by hormonal signals and hence may be modified by endocrine-active contaminants. If so, the functions of plumage (e.g. communication for mating or territorial defense) may be compromised by exposure to such compounds. Captive American kestrels were fed Aroclor 1242 at 0. 6.0. and 60.0 ppm (n = 6 males and 6 females per treatment) mixed in their normal diet. Concentrations of plasma estradiol and thyroxine were measured weekly from the beginning of treatment. Measured plumage characteristics included width of the black subterminal band on the tail, color (a composite index of hue and saturation), reflectance from 230 to 800 min. pattern of feather loss and regrowth on the tail and wing. and timing of onset and duration of molt. Aroclor 1242 depressed plasma thyroxine. Plasma estradiol levels remained low due to the phase of the breeding cycle. Treatments did not disrupt the measured plumage characteristics. This may be due to timing or dose of exposure or to genetic factors.
Polymorphism at a mimicry supergene maintained by opposing frequency-dependent selection pressures.
Chouteau, Mathieu; Llaurens, Violaine; Piron-Prunier, Florence; Joron, Mathieu
2017-08-01
Explaining the maintenance of adaptive diversity within populations is a long-standing goal in evolutionary biology, with important implications for conservation, medicine, and agriculture. Adaptation often leads to the fixation of beneficial alleles, and therefore it erodes local diversity so that understanding the coexistence of multiple adaptive phenotypes requires deciphering the ecological mechanisms that determine their respective benefits. Here, we show how antagonistic frequency-dependent selection (FDS), generated by natural and sexual selection acting on the same trait, maintains mimicry polymorphism in the toxic butterfly Heliconius numata Positive FDS imposed by predators on mimetic signals favors the fixation of the most abundant and best-protected wing-pattern morph, thereby limiting polymorphism. However, by using mate-choice experiments, we reveal disassortative mate preferences of the different wing-pattern morphs. The resulting negative FDS on wing-pattern alleles is consistent with the excess of heterozygote genotypes at the supergene locus controlling wing-pattern variation in natural populations of H. numata The combined effect of positive and negative FDS on visual signals is sufficient to maintain a diversity of morphs displaying accurate mimicry with other local prey, although some of the forms only provide moderate protection against predators. Our findings help understand how alternative adaptive phenotypes can be maintained within populations and emphasize the need to investigate interactions between selective pressures in other cases of puzzling adaptive polymorphism.
Polymorphism at a mimicry supergene maintained by opposing frequency-dependent selection pressures
Chouteau, Mathieu; Llaurens, Violaine; Piron-Prunier, Florence; Joron, Mathieu
2017-01-01
Explaining the maintenance of adaptive diversity within populations is a long-standing goal in evolutionary biology, with important implications for conservation, medicine, and agriculture. Adaptation often leads to the fixation of beneficial alleles, and therefore it erodes local diversity so that understanding the coexistence of multiple adaptive phenotypes requires deciphering the ecological mechanisms that determine their respective benefits. Here, we show how antagonistic frequency-dependent selection (FDS), generated by natural and sexual selection acting on the same trait, maintains mimicry polymorphism in the toxic butterfly Heliconius numata. Positive FDS imposed by predators on mimetic signals favors the fixation of the most abundant and best-protected wing-pattern morph, thereby limiting polymorphism. However, by using mate-choice experiments, we reveal disassortative mate preferences of the different wing-pattern morphs. The resulting negative FDS on wing-pattern alleles is consistent with the excess of heterozygote genotypes at the supergene locus controlling wing-pattern variation in natural populations of H. numata. The combined effect of positive and negative FDS on visual signals is sufficient to maintain a diversity of morphs displaying accurate mimicry with other local prey, although some of the forms only provide moderate protection against predators. Our findings help understand how alternative adaptive phenotypes can be maintained within populations and emphasize the need to investigate interactions between selective pressures in other cases of puzzling adaptive polymorphism. PMID:28673971
Fossil scales illuminate the early evolution of lepidopterans and structural colors
Zhang, Qingqing; Starkey, Timothy A.; McNamara, Maria E.; Jarzembowski, Edmund A.; Kelly, Richard; Ren, Xiaoyin; Chen, Jun; Zhang, Haichun
2018-01-01
Lepidopteran scales exhibit remarkably complex ultrastructures, many of which produce structural colors that are the basis for diverse communication strategies. Little is known, however, about the early evolution of lepidopteran scales and their photonic structures. We report scale architectures from Jurassic Lepidoptera from the United Kingdom, Germany, Kazakhstan, and China and from Tarachoptera (a stem group of Amphiesmenoptera) from mid-Cretaceous Burmese amber. The Jurassic lepidopterans exhibit a type 1 bilayer scale vestiture: an upper layer of large fused cover scales and a lower layer of small fused ground scales. This scale arrangement, plus preserved herringbone ornamentation on the cover scale surface, is almost identical to those of some extant Micropterigidae. Critically, the fossil scale ultrastructures have periodicities measuring from 140 to 2000 nm and are therefore capable of scattering visible light, providing the earliest evidence of structural colors in the insect fossil record. Optical modeling confirms that diffraction-related scattering mechanisms dominate the photonic properties of the fossil cover scales, which would have displayed broadband metallic hues as in numerous extant Micropterigidae. The fossil tarachopteran scales exhibit a unique suite of characteristics, including small size, elongate-spatulate shape, ridged ornamentation, and irregular arrangement, providing novel insight into the early evolution of lepidopteran scales. Combined, our results provide the earliest evidence for structural coloration in fossil lepidopterans and support the hypothesis that fused wing scales and the type 1 bilayer covering are groundplan features of the group. Wing scales likely had deep origins in earlier amphiesmenopteran lineages before the appearance of the Lepidoptera. PMID:29651455
Fossil scales illuminate the early evolution of lepidopterans and structural colors.
Zhang, Qingqing; Mey, Wolfram; Ansorge, Jörg; Starkey, Timothy A; McDonald, Luke T; McNamara, Maria E; Jarzembowski, Edmund A; Wichard, Wilfried; Kelly, Richard; Ren, Xiaoyin; Chen, Jun; Zhang, Haichun; Wang, Bo
2018-04-01
Lepidopteran scales exhibit remarkably complex ultrastructures, many of which produce structural colors that are the basis for diverse communication strategies. Little is known, however, about the early evolution of lepidopteran scales and their photonic structures. We report scale architectures from Jurassic Lepidoptera from the United Kingdom, Germany, Kazakhstan, and China and from Tarachoptera (a stem group of Amphiesmenoptera) from mid-Cretaceous Burmese amber. The Jurassic lepidopterans exhibit a type 1 bilayer scale vestiture: an upper layer of large fused cover scales and a lower layer of small fused ground scales. This scale arrangement, plus preserved herringbone ornamentation on the cover scale surface, is almost identical to those of some extant Micropterigidae. Critically, the fossil scale ultrastructures have periodicities measuring from 140 to 2000 nm and are therefore capable of scattering visible light, providing the earliest evidence of structural colors in the insect fossil record. Optical modeling confirms that diffraction-related scattering mechanisms dominate the photonic properties of the fossil cover scales, which would have displayed broadband metallic hues as in numerous extant Micropterigidae. The fossil tarachopteran scales exhibit a unique suite of characteristics, including small size, elongate-spatulate shape, ridged ornamentation, and irregular arrangement, providing novel insight into the early evolution of lepidopteran scales. Combined, our results provide the earliest evidence for structural coloration in fossil lepidopterans and support the hypothesis that fused wing scales and the type 1 bilayer covering are groundplan features of the group. Wing scales likely had deep origins in earlier amphiesmenopteran lineages before the appearance of the Lepidoptera.
Structural analysis and testing of a carbon-composite wing using fiber Bragg gratings
NASA Astrophysics Data System (ADS)
Nicolas, Matthew James
The objective of this study was to determine the deflected wing shape and the out-of-plane loads of a large-scale carbon-composite wing of an ultralight aerial vehicle using Fiber Bragg Grating (FBG) technology. The composite wing was instrumented with an optical fiber on its top and bottom surfaces positioned over the main spar, resulting in approximately 780 strain sensors bonded to the wings. The strain data from the FBGs was compared to that obtained from four conventional strain gages, and was used to obtain the out-of-plane loads as well as the wing shape at various load levels using NASA-developed real-time load and displacement algorithms. The composite wing measured 5.5 meters and was fabricated from laminated carbon uniaxial and biaxial prepreg fabric with varying laminate ply patterns and wall thickness dimensions. A three-tier whiffletree system was used to load the wing in a manner consistent with an in-flight loading condition.
Kim, Hana; Youk, Ji Hyun; Gweon, Hye Mi; Kim, Jeong-Ah; Son, Eun Ju
2013-08-01
To compare the diagnostic performance of qualitative shear-wave elastography (SWE) according to three different color map opacities for breast masses 101 patients aged 21-77 years with 113 breast masses underwent B-mode US and SWE under three different color map opacities (50%, 19% and 100%) before biopsy or surgery. Following SWE features were reviewed: visual pattern classification (pattern 1-4), color homogeneity (Ehomo) and six-point color score of maximum elasticity (Ecol). Combined with B-mode US and SWE, the likelihood of malignancy (LOM) was also scored. The area under the curve (AUC) was obtained by ROC curve analysis to assess the diagnostic performance under each color opacity. A visual color pattern, Ehomo, Ecol and LOM scoring were significantly different between benign and malignant lesions under all color opacities (P<0.001). For 50% opacity, AUCs of visual color pattern, Ecol, Ehomo and LOM scoring were 0.902, 0.951, 0.835 and 0.975. But, for each SWE feature, there was no significant difference in the AUC among three different color opacities. For all color opacities, visual color pattern and Ecol showed significantly higher AUC than Ehomo. In addition, a combined set of B-mode US and SWE showed significantly higher AUC than SWE alone for color patterns, Ehomo, but no significant difference was found in Ecol. Qualitative SWE was useful to differentiate benign from malignant breast lesion under all color opacities. The difference in color map opacity did not significantly influence diagnostic performance of SWE. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Factors affecting the efficacy of a vinegar trap for Drosophila suzukii (Diptera: Drosophilidae)
USDA-ARS?s Scientific Manuscript database
Studies were conducted to develop an optimized, economical trap for monitoring the spotted wing fruit fly, Drosophila suzukii Matsumura. Flies were attracted to dark colors ranging from red to black compared with low attraction to white, yellow, and light blue. Similarly, fly catches in 237 ml plast...
The effect of wing flexibility on sound generation of flapping wings.
Geng, Biao; Xue, Qian; Zheng, Xudong; Liu, Geng; Ren, Yan; Dong, Haibo
2017-12-13
In this study, the unsteady flow and acoustic characteristics of a three-dimensional (3D) flapping wing model of a Tibicen linnei cicada in forward-flight are numerically investigated. A single cicada wing is modelled as a membrane with a prescribed motion reconstructed from high-speed videos of a live insect. The numerical solution takes a hydrodynamic/acoustic splitting approach: the flow field is solved with an incompressible Navier-Stokes flow solver based on an immersed boundary method, and the acoustic field is solved with linearized perturbed compressible equations. The 3D simulation allows for the examination of both the directivity and frequency compositions of the flapping wing sound in a full space. Along with the flexible wing model, a rigid wing model that is extracted from real motion is also simulated to investigate the effects of wing flexibility. The simulation results show that the flapping sound is directional; the dominant frequency varies around the wing. The first and second frequency harmonics show different radiation patterns in the rigid and flexible wing cases, which are demonstrated to be highly associated with wing kinematics and loadings. Furthermore, the rotation and deformation in the flexible wing is found to help lower the sound strength in all directions.
Emblem of the Apollo 17 lunar landing mission
NASA Technical Reports Server (NTRS)
1972-01-01
This is the Official emblem of the Apollo 17 lunar landing mission which will be flown by Astronauts Eugene A. Cernan, Ronald E. Evans and Harrison H. Schmitt. The insignia is dominated by the image of Apollo, the Greek sun god. Suspended in space behind the head of Apollo is an American eagle of contemporary design, the red bars of the eagle's wing represent the bars in the U.S. flag; the three white stars symbolize the three astronaut crewmen. The background is deep blue space and within it are the Moon, the planet Saturn and a spiral galaxy or nebula. The Moon is partially overlaid by the eagle's wing suggesting that this is a celestial body that man has visited and in that sense conquered. The thrust of the eagle and the gaze of Apollo to the right and toward Saturn and the galaxy is meant to imply that man's goals in space will someday include the planets and perhaps the stars. The colors of the emblem are red, white and blue, the colors of our flag; with the addition of gold, to
Cong, Rui; Li, Jing; Guo, Song
2017-02-01
To examine the efficacy of qualitative shear wave elastography (SWE) in the classification and evaluation of solid breast masses, and to compare this method with conventional ultrasonograghy (US), quantitative SWE parameters and qualitative SWE classification proposed before. From April 2015 to March 2016, 314 consecutive females with 325 breast masses who decided to undergo core needle biopsy and/or surgical biopsy were enrolled. Conventional US and SWE were previously performed in all enrolled subjects. Each mass was classified by two different qualitative classifications. One was established in our study, herein named the Qual1. Qual1 could classify the SWE images into five color patterns by the visual evaluations: Color pattern 1 (homogeneous pattern); Color pattern 2 (comparative homogeneous pattern); Color pattern 3 (irregularly heterogeneous pattern); Color pattern 4 (intralesional echo pattern); and Color pattern 5 (the stiff rim sign pattern). The second qualitative classification was named Qual2 here, and included a four-color overlay pattern classification (Tozaki and Fukuma, Acta Radiologica, 2011). The Breast Imaging Reporting and Data System (BI-RADS) assessment and quantitative SWE parameters were recorded. Diagnostic performances of conventional US, SWE parameters, and combinations of US and SWE parameters were compared. With pathological results as the gold standard, of the 325 examined breast masses, 139 (42.77%) samples were malignant and 186 (57.23%) were benign. The Qual1 showed a higher Az value than the Qual2 and quantitative SWE parameters (all P<0.05). When applying Qual1=Color pattern 1 for downgrading and Qual1=Color pattern 5 for upgrading the BI-RADS categories, we obtained the highest Az value (0.951), and achieved a significantly higher specificity (86.56%, P=0.002) than that of the US (81.18%) with the same sensitivity (94.96%). The qualitative classification proposed in this study may be representative of SWE parameters and has potential to be relevant assistance in breast mass diagnoses. Copyright © 2016. Published by Elsevier B.V.
The wing and the eye: a parsimonious theory for scaling and growth control?
Romanova-Michaelides, Maria; Aguilar-Hidalgo, Daniel; Jülicher, Frank; Gonzalez-Gaitan, Marcos
2015-01-01
How a developing organ grows and patterns to its final shape is an important question in developmental biology. Studies of growth and patterning in the Drosophila wing imaginal disc have identified a key player, the morphogen Decapentaplegic (Dpp). These studies provided insights into our understanding of growth control and scaling: expansion of the Dpp gradient correlated with the growth of the tissue. A recent report on growth of a Drosophila organ other than the wing, the eye imaginal disc, prompts a reconsideration of our models of growth control. Despite striking differences between the two, the Dpp gradient scales with the target tissues of both organs and the growth of both the wing and the eye is controlled by Dpp. The goal of this review is to discuss whether a parsimonious model of scaling and growth control can explain the relationship between the Dpp gradient and growth in these two different developmental systems. © 2015 Wiley Periodicals, Inc.
Gradual and contingent evolutionary emergence of leaf mimicry in butterfly wing patterns.
Suzuki, Takao K; Tomita, Shuichiro; Sezutsu, Hideki
2014-11-25
Special resemblance of animals to natural objects such as leaves provides a representative example of evolutionary adaptation. The existence of such sophisticated features challenges our understanding of how complex adaptive phenotypes evolved. Leaf mimicry typically consists of several pattern elements, the spatial arrangement of which generates the leaf venation-like appearance. However, the process by which leaf patterns evolved remains unclear. In this study we show the evolutionary origin and process for the leaf pattern in Kallima (Nymphalidae) butterflies. Using comparative morphological analyses, we reveal that the wing patterns of Kallima and 45 closely related species share the same ground plan, suggesting that the pattern elements of leaf mimicry have been inherited across species with lineage-specific changes of their character states. On the basis of these analyses, phylogenetic comparative methods estimated past states of the pattern elements and enabled reconstruction of the wing patterns of the most recent common ancestor. This analysis shows that the leaf pattern has evolved through several intermediate patterns. Further, we use Bayesian statistical methods to estimate the temporal order of character-state changes in the pattern elements by which leaf mimesis evolved, and show that the pattern elements changed their spatial arrangement (e.g., from a curved line to a straight line) in a stepwise manner and finally establish a close resemblance to a leaf venation-like appearance. Our study provides the first evidence for stepwise and contingent evolution of leaf mimicry. Leaf mimicry patterns evolved in a gradual, rather than a sudden, manner from a non-mimetic ancestor. Through a lineage of Kallima butterflies, the leaf patterns evolutionarily originated through temporal accumulation of orchestrated changes in multiple pattern elements.
A Model for Selection of Eyespots on Butterfly Wings.
Sekimura, Toshio; Venkataraman, Chandrasekhar; Madzvamuse, Anotida
2015-01-01
The development of eyespots on the wing surface of butterflies of the family Nympalidae is one of the most studied examples of biological pattern formation.However, little is known about the mechanism that determines the number and precise locations of eyespots on the wing. Eyespots develop around signaling centers, called foci, that are located equidistant from wing veins along the midline of a wing cell (an area bounded by veins). A fundamental question that remains unsolved is, why a certain wing cell develops an eyespot, while other wing cells do not. We illustrate that the key to understanding focus point selection may be in the venation system of the wing disc. Our main hypothesis is that changes in morphogen concentration along the proximal boundary veins of wing cells govern focus point selection. Based on previous studies, we focus on a spatially two-dimensional reaction-diffusion system model posed in the interior of each wing cell that describes the formation of focus points. Using finite element based numerical simulations, we demonstrate that variation in the proximal boundary condition is sufficient to robustly select whether an eyespot focus point forms in otherwise identical wing cells. We also illustrate that this behavior is robust to small perturbations in the parameters and geometry and moderate levels of noise. Hence, we suggest that an anterior-posterior pattern of morphogen concentration along the proximal vein may be the main determinant of the distribution of focus points on the wing surface. In order to complete our model, we propose a two stage reaction-diffusion system model, in which an one-dimensional surface reaction-diffusion system, posed on the proximal vein, generates the morphogen concentrations that act as non-homogeneous Dirichlet (i.e., fixed) boundary conditions for the two-dimensional reaction-diffusion model posed in the wing cells. The two-stage model appears capable of generating focus point distributions observed in nature. We therefore conclude that changes in the proximal boundary conditions are sufficient to explain the empirically observed distribution of eyespot focus points on the entire wing surface. The model predicts, subject to experimental verification, that the source strength of the activator at the proximal boundary should be lower in wing cells in which focus points form than in those that lack focus points. The model suggests that the number and locations of eyespot foci on the wing disc could be largely controlled by two kinds of gradients along two different directions, that is, the first one is the gradient in spatially varying parameters such as the reaction rate along the anterior-posterior direction on the proximal boundary of the wing cells, and the second one is the gradient in source values of the activator along the veins in the proximal-distal direction of the wing cell.
Keren-Rotem, Tammy; Levy, Noga; Wolf, Lior; Bouskila, Amos; Geffen, Eli
2016-01-01
Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling. PMID:27409771
NASA Astrophysics Data System (ADS)
Besson, Marc; Salis, Pauline; Laudet, Vincent; Lecchini, David
2018-03-01
Color polymorphism is widespread in animals and can be associated with temporary adjustments to environmental variables (phenotypic plasticity). In teleost fishes, one of the most remarkable examples of color plasticity is background adaptation in flatfishes. However, such rapid and complete changes in body color and pattern remain relatively unreported in other species. The convict surgeonfish Acanthurus triostegus is a gregarious species whose body color pattern consists of black vertical bars on a whitish body. Here, we describe an entirely reverse body color pattern (white vertical bars on a blackish body) that we observed in some A. triostegus juveniles in a nursery area at Moorea Island, French Polynesia. In aquaria, we determined that change from one color pattern to the other is rapid, reversible, and corresponds to phenotypic plasticity associated with aggressive behavior.
Structural Color Model Based on Surface Morphology of MORPHO Butterfly Wing Scale
NASA Astrophysics Data System (ADS)
Huang, Zhongjia; Cai, Congcong; Wang, Gang; Zhang, Hui; Huttula, Marko; Cao, Wei
2016-05-01
Color production through structural coloration is created by micrometer and sub-micrometer surface textures which interfere with visible light. The shiny blue of morpho menelaus is a typical example of structural coloring. Modified from morphology of the morpho scale, a structure of regular windows with two side offsets was constructed on glass substrates. Optical properties of the bioinspired structure were studied through numerical simulations of light scattering. Results show that the structure can generate monochromatic light scattering. Wavelength of scattered light is tunable via changing the spacing between window shelves. Compared to original butterfly model, the modified one possesses larger illumination scopes in azimuthal distributions despite being less in polar directions. Present bionic structure is periodically repeated and is easy to fabricate. It is hoped that the computational materials design work can inspire future experimental realizations of such a structure in photonics applications.
NASA Technical Reports Server (NTRS)
Phillips, W. H. (Inventor)
1983-01-01
A cruciform wing structure for a solar powered aircraft is disclosed. Solar cells are mounted on horizontal wing surfaces. Wing surfaces with spanwise axis perpendicular to surfaces maintain these surfaces normal to the Sun's rays by allowing aircraft to be flown in a controlled pattern at a large bank angle. The solar airplane may be of conventional design with respect to fuselage, propeller and tail, or may be constructed around a core and driven by propeller mechanisms attached near the tips of the airfoils.
Penz, Carla M; Alexander, Laura G; Devries, Philip J
2014-10-20
This study provides updated species definitions for five rose-colored Cithaerias butterflies, starting with a historical overview of their taxonomy. Given their mostly transparent wings, genitalia morphology yielded the most reliable characters for species definition and identification. Genitalic divergence is more pronounced when multiple species occur in sympatry than between parapatric taxa. Cithaerias aurorina is granted full species status, C. cliftoni is reinstated as a full species, and one new combination is proposed, i.e. C. aurora tambopata. Two new synonyms are proposed, Callitaera phantoma and Callitaera aura = Cithaerias aurora.
Simulation of Cell Patterning Triggered by Cell Death and Differential Adhesion in Drosophila Wing.
Nagai, Tatsuzo; Honda, Hisao; Takemura, Masahiko
2018-02-27
The Drosophila wing exhibits a well-ordered cell pattern, especially along the posterior margin, where hair cells are arranged in a zigzag pattern in the lateral view. Based on an experimental result observed during metamorphosis of Drosophila, we considered that a pattern of initial cells autonomously develops to the zigzag pattern through cell differentiation, intercellular communication, and cell death (apoptosis) and performed computer simulations of a cell-based model of vertex dynamics for tissues. The model describes the epithelial tissue as a monolayer cell sheet of polyhedral cells. Their vertices move according to equations of motion, minimizing the sum total of the interfacial and elastic energies of cells. The interfacial energy densities between cells are introduced consistently with an ideal zigzag cell pattern, extracted from the experimental result. The apoptosis of cells is modeled by gradually reducing their equilibrium volume to zero and by assuming that the hair cells prohibit neighboring cells from undergoing apoptosis. Based on experimental observations, we also assumed wing elongation along the proximal-distal axis. Starting with an initial cell pattern similar to the micrograph experimentally obtained just before apoptosis, we carried out the simulations according to the model mentioned above and successfully reproduced the ideal zigzag cell pattern. This elucidates a physical mechanism of patterning triggered by cell apoptosis theoretically and exemplifies, to our knowledge, a new framework to study apoptosis-induced patterning. We conclude that the zigzag cell pattern is formed by an autonomous communicative process among the participant cells. Copyright © 2018 Biophysical Society. All rights reserved.
Beldade, P; McMillan, W O; Papanicolaou, A
2008-02-01
Technological and conceptual advances of the last decade have led to an explosion of genomic data and the emergence of new research avenues. Evolutionary and ecological functional genomics, with its focus on the genes that affect ecological success and adaptation in natural populations, benefits immensely from a phylogenetically widespread sampling of biological patterns and processes. Among those organisms outside established model systems, butterflies offer exceptional opportunities for multidisciplinary research on the processes generating and maintaining variation in ecologically relevant traits. Here we highlight research on wing color pattern variation in two groups of Nymphalid butterflies, the African species Bicyclus anynana (subfamily Satyrinae) and species of the South American genus Heliconius (subfamily Heliconiinae), which are emerging as important systems for studying the nature and origins of functional diversity. Growing genomic resources including genomic and cDNA libraries, dense genetic maps, high-density gene arrays, and genetic transformation techniques are extending current gene mapping and expression profiling analysis and enabling the next generation of research questions linking genes, development, form, and fitness. Efforts to develop such resources in Bicyclus and Heliconius underscore the general challenges facing the larger research community and highlight the need for a community-wide effort to extend ongoing functional genomic research on butterflies.
Clothing Matching for Visually Impaired Persons
Yuan, Shuai; Tian, YingLi; Arditi, Aries
2012-01-01
Matching clothes is a challenging task for many blind people. In this paper, we present a proof of concept system to solve this problem. The system consists of 1) a camera connected to a computer to perform pattern and color matching process; 2) speech commands for system control and configuration; and 3) audio feedback to provide matching results for both color and patterns of clothes. This system can handle clothes in deficient color without any pattern, as well as clothing with multiple colors and complex patterns to aid both blind and color deficient people. Furthermore, our method is robust to variations of illumination, clothing rotation and wrinkling. To evaluate the proposed prototype, we collect two challenging databases including clothes without any pattern, or with multiple colors and different patterns under different conditions of lighting and rotation. Results reported here demonstrate the robustness and effectiveness of the proposed clothing matching system. PMID:22523465
Clothing Matching for Visually Impaired Persons.
Yuan, Shuai; Tian, Yingli; Arditi, Aries
2011-01-01
Matching clothes is a challenging task for many blind people. In this paper, we present a proof of concept system to solve this problem. The system consists of 1) a camera connected to a computer to perform pattern and color matching process; 2) speech commands for system control and configuration; and 3) audio feedback to provide matching results for both color and patterns of clothes. This system can handle clothes in deficient color without any pattern, as well as clothing with multiple colors and complex patterns to aid both blind and color deficient people. Furthermore, our method is robust to variations of illumination, clothing rotation and wrinkling. To evaluate the proposed prototype, we collect two challenging databases including clothes without any pattern, or with multiple colors and different patterns under different conditions of lighting and rotation. Results reported here demonstrate the robustness and effectiveness of the proposed clothing matching system.
Domingue, Michael J.; Lakhtakia, Akhlesh; Pulsifer, Drew P.; Hall, Loyal P.; Badding, John V.; Bischof, Jesse L.; Martín-Palma, Raúl J.; Imrei, Zoltán; Janik, Gergely; Mastro, Victor C.; Hazen, Missy; Baker, Thomas C.
2014-01-01
Recent advances in nanoscale bioreplication processes present the potential for novel basic and applied research into organismal behavioral processes. Insect behavior potentially could be affected by physical features existing at the nanoscale level. We used nano-bioreplicated visual decoys of female emerald ash borer beetles (Agrilus planipennis) to evoke stereotypical mate-finding behavior, whereby males fly to and alight on the decoys as they would on real females. Using an industrially scalable nanomolding process, we replicated and evaluated the importance of two features of the outer cuticular surface of the beetle’s wings: structural interference coloration of the elytra by multilayering of the epicuticle and fine-scale surface features consisting of spicules and spines that scatter light into intense strands. Two types of decoys that lacked one or both of these elements were fabricated, one type nano-bioreplicated and the other 3D-printed with no bioreplicated surface nanostructural elements. Both types were colored with green paint. The light-scattering properties of the nano-bioreplicated surfaces were verified by shining a white laser on the decoys in a dark room and projecting the scattering pattern onto a white surface. Regardless of the coloration mechanism, the nano-bioreplicated decoys evoked the complete attraction and landing sequence of Agrilus males. In contrast, males made brief flying approaches toward the decoys without nanostructured features, but diverted away before alighting on them. The nano-bioreplicated decoys were also electroconductive, a feature used on traps such that beetles alighting onto them were stunned, killed, and collected. PMID:25225359
Molecular patterns of X chromosome-linked color vision genes among 134 men of European ancestry.
Drummond-Borg, M; Deeb, S S; Motulsky, A G
1989-01-01
We used Southern blot hybridization to study X chromosome-linked color vision genes encoding the apoproteins of red and green visual pigments in 134 unselected Caucasian men. One hundred and thirteen individuals (84.3%) had a normal arrangement of their color vision pigment genes. All had one red pigment gene; the number of green pigment genes ranged from one to five with a mode of two. The frequency of molecular genotypes indicative of normal color vision (84.3%) was significantly lower than had been observed in previous studies of color vision phenotypes. Color vision defects can be due to deletions of red or green pigment genes or due to formation of hybrid genes comprising portions of both red and green pigment genes [Nathans, J., Piantanida, T.P., Eddy, R.L., Shows, T.B., Jr., & Hogness, D.S. (1986) Science 232, 203-210]. Characteristic anomalous patterns were seen in 15 (11.2%) individuals: 7 (5.2%) had patterns characteristic of deuteranomaly (mild defect in green color perception), 2 (1.5%) had patterns characteristic of deuteranopia (severe defect in green color perception), and 6 (4.5%) had protan patterns (the red perception defects protanomaly and protanopia cannot be differentiated by current molecular methods). Previously undescribed hybrid gene patterns consisting of both green and red pigment gene fragments in addition to normal red and green genes were observed in another 6 individuals (4.5%). Only 2 of these patterns were considered as deuteranomalous. Thus, DNA testing detected anomalous color vision pigment genes at a higher frequency than expected from phenotypic color vision tests. Some color vision gene arrays associated with hybrid genes are likely to mediate normal color vision. Images PMID:2915991
Nurses' uniform color and feelings/emotions in school-aged children receiving health care.
Albert, Nancy M; Burke, Jane; Bena, James F; Morrison, Shannon M; Forney, Jennifer; Krajewski, Susan
2013-04-01
Children may fear nurses wearing white uniforms. When emotions and uniform color were studied in 233 children, many positive emotions were most often associated with blue, bold pink-patterned, or yellow-patterned tops (all p ≤ .002). Negative emotions were not associated with uniform top colors (all p < .001). However, after excluding "uniform color does not matter," 8 negative emotions were most often associated with white uniform color (p < .001-.04), and 2 others were most often associated with the yellow-patterned top. Bold pink-patterned and solid blue uniform tops were preferred. In conclusion, children's emotions were associated with nurse uniform color. Copyright © 2013 Elsevier Inc. All rights reserved.
Variable environmental effects on a multicomponent sexually selected trait.
Cole, Gemma L; Endler, John A
2015-04-01
Multicomponent signals are made up of interacting elements that generate a functional signaling unit. The interactions between signal components and their effects on individual fitness are not well understood, and the effect of environment is even less so. It is usually assumed that color patterns appear the same in all light environments and that the effects of each color are additive. Using guppies, Poecilia reticulata, we investigated the effect of water color on the interactions between components of sexually selected male coloration. Through behavioral mate choice trials in four different water colors, we estimated the attractiveness of male color patterns, using multivariate fitness estimates and overall signal contrast. Our results show that females exhibit preferences that favor groups of colors rather than individual colors independently and that each environment favors different color combinations. We found that these effects are consistent with female guppies selecting entire color patterns on the basis of overall visual contrast. This suggests that both individuals and populations inhabiting different light environments will be subject to divergent, multivariate selection. Although the appearance of color patterns changes with light environment, achromatic components change little, suggesting that these could function in species recognition or other aspects of communication that must work across environments. Consequently, we predict different phylogenetic patterns between chromatic and achromatic signals within the same clades.
Development of Bird-like Micro Aerial Vehicle with Flapping and Feathering Wing Motions
NASA Astrophysics Data System (ADS)
Maglasang, Jonathan; Goto, Norihiro; Isogai, Koji
To investigate the feasibility of a highly efficient flapping system capable of avian maneuvers, such as rapid takeoff, hover and gliding, a full scale bird-like (ornithopter) flapping-wing micro aerial vehicle (MAV) shaped and patterned after a typical pigeon (Columba livia) has been designed and constructed. Both numerical and experimental methods have been used in the development of this vehicle. This flapping-wing micro aerial vehicle utilizes both the flapping and feathering motions of an avian wing by employing a novel flapping-feathering mechanism, which has been synthesized and constructed so as to best describe the properly coordinated flapping and feathering wing motions at phase angle difference of 90° in a horizontal steady level flight condition. This design allows high flapping and feathering amplitudes and is configurable for asymmetric wing motions which are desirable in high-speed flapping flight and maneuvering. The preliminary results indicate its viability as a practical and an efficient flapping-wing micro aerial vehicle.
Cicada-Wing-Inspired Self-Cleaning Antireflection Coatings on Polymer Substrates.
Chen, Ying-Chu; Huang, Zhe-Sheng; Yang, Hongta
2015-11-18
The cicada has transparent wings with remarkable self-cleaning properties and high transmittance over the whole visible spectral range, which is derived from periodic conical structures covering the wing surface. Here we report a scalable self-assembly technique for fabricating multifunctional optical coatings that mimic cicada-wing structures. Spin-coated two-dimensional non-close-packed colloidal crystals are utilized as etching masks to pattern subwavelength-structured cone arrays directly on polymer substrates. The resulting gratings exhibit broadband antireflection performance and superhydrophobic properties after surface modification. The dependence of the cone shape and size on the antireflective and self-cleaning properties has also been investigated in this study.
Sri Lankan Villagers' Attitudes toward Winged Bean, New Third World Food Source.
ERIC Educational Resources Information Center
Hacklander, Effie H.
1984-01-01
Discusses a survey on the acquisition, preparation, and consumption patterns of the winged bean as a food source in various parts of Sri Lanka. It was found that expanding the knowledge and production of indigenous legumes can help satisfy food needs of Third World countries. (JOW)
Slender wing theory including regions of embedded total pressure loss
NASA Technical Reports Server (NTRS)
Mccune, James E.; Tavares, T. Sean; Lee, Norman K. W.; Weissbein, David
1988-01-01
An aerodynamic theory of the flow about slender delta wings is described. The theory includes a treatment of the self-consistent development of the vortex wake patterns above the wing necessary to maintain smooth flow at the wing edges. The paper focuses especially on the formation within the wake of vortex 'cores' as embedded regions of total pressure loss, fed and maintained by umbilical vortex sheets emanating from the wing edges. Criteria are developed for determining the growing size and location of these cores, as well as the distribution and strength of the vorticity within them. In this paper, however, the possibility of vortex breakup is omitted. The aerodynamic consequences of the presence and evolution of the cores and the associated wake structure are illustrated and discussed. It is noted that wake history effects can have substantial influence on the distribution of normal force on the wing as well as on its magnitude.
The effects of leading edge modifications on the post-stall characteristics of wings
NASA Technical Reports Server (NTRS)
Winkelmann, A. E.; Barlow, J. B.; Saini, J. K.; Anderson, J. D., Jr.; Jones, E.
1980-01-01
An investigation of the effects of leading edge modifications on the post-stall characteristics of two rectangular planform wings in a series of low speed wind tunnel tests is presented. Abrupt discontinuities in the leading edge shape of the wings were produced by placing a nose glove over a portion of the span or by deflecting sections of a segmented leading edge flap. Six component balance data, oil flow visualization photographs, and pressure distribution measurements were obtained, and tests made to study the development of flow separation at stall on small scale planform wing models. Results of oil flow visualization tests at and beyond stall showed the formation of counter-rotating swirl patterns on the upper surface of the '2-D' and '3-D' wings, and results of a numerical lifting line technique applied to wings with leading edge modifications are included.
NASA Technical Reports Server (NTRS)
Mann, M. J.; Mercer, C. E.
1986-01-01
A transonic computational analysis method and a transonic design procedure have been used to design the wing and the canard of a forward-swept-wing fighter configuration for good transonic maneuver performance. A model of this configuration was tested in the Langley 16-Foot Transonic Tunnel. Oil-flow photographs were obtained to examine the wind flow patterns at Mach numbers from 0.60 to 0.90. The transonic theory gave a reasonably good estimate of the wing pressure distributions at transonic maneuver conditions. Comparison of the forward-swept-wing configuration with an equivalent aft-swept-wing-configuration showed that, at a Mach number of 0.90 and a lift coefficient of 0.9, the two configurations have the same trimmed drag. The forward-swept wing configuration was also found to have trimmed drag levels at transonic maneuver conditions which are comparable to those of the HiMAT (highly maneuverable aircraft technology) configuration and the X-29 forward-swept-wing research configuration. The configuration of this study was also tested with a forebody strake.
Qualitative skeletal correlates of wing shape in extant birds (Aves: Neoaves).
Hieronymus, Tobin L
2015-02-27
Among living fliers (birds, bats, and insects), birds display relatively high aspect ratios, a dimensionless shape variable that distinguishes long and narrow vs. short and broad wings. Increasing aspect ratio results in a functional tradeoff between low induced drag (efficient cruise) and increased wing inertia (difficult takeoff). Given the wide scope of its functional effects, the pattern of aspect ratio evolution is an important factor that contributes to the substantial ecological and phylogenetic diversity of living birds. However, because the feathers that define the wingtip (and hence wingspan and aspect ratio) often do not fossilize, resolution in the pattern of avian wing shape evolution is obscured by missing information. Here I use a comparative approach to investigate the relationship between skeletal proxies of flight feather attachment and wing shape. An accessory lobe of the internal index process of digit II-1, a bony correlate of distal primary attachment, shows weak but statistically significant relationships to aspect ratio and mass independent of other skeletal morphology. The dorsal phalangeal fossae of digit II-1, which house distal primaries VIII and IX, also show a trend of increased prominence with higher aspect ratio. Quill knobs on the ulna are examined concurrently, but do not show consistent signal with respect to wing shape. Although quill knobs are cited as skeletal correlates of flight performance in birds, their relationship to wing shape is inconsistent among extant taxa, and may reflect diverging selection pressures acting on a conserved architecture. In contrast, correlates of distal primary feather attachment on the major digit show convergent responses to increasing aspect ratio. In light of the diversity of musculoskeletal and integumentary mophology that underlies wing shape in different avian clades, it is unlikely that a single skeletal feature will show consistent predictive power across Neoaves. Confident inference of wing shape in basal ornithurine birds will require multiple lines of evidence, together with an understanding of clade-specific evolutionary trends within the crown.
Fossil evidence for evolution of the shape and color of penguin feathers.
Clarke, Julia A; Ksepka, Daniel T; Salas-Gismondi, Rodolfo; Altamirano, Ali J; Shawkey, Matthew D; D'Alba, Liliana; Vinther, Jakob; DeVries, Thomas J; Baby, Patrice
2010-11-12
Penguin feathers are highly modified in form and function, but there have been no fossils to inform their evolution. A giant penguin with feathers was recovered from the late Eocene (~36 million years ago) of Peru. The fossil reveals that key feathering features, including undifferentiated primary wing feathers and broad body contour feather shafts, evolved early in the penguin lineage. Analyses of fossilized color-imparting melanosomes reveal that their dimensions were similar to those of non-penguin avian taxa and that the feathering may have been predominantly gray and reddish-brown. In contrast, the dark black-brown color of extant penguin feathers is generated by large, ellipsoidal melanosomes previously unknown for birds. The nanostructure of penguin feathers was thus modified after earlier macrostructural modifications of feather shape linked to aquatic flight.
Experimental and numerical studies of beetle-inspired flapping wing in hovering flight.
Van Truong, Tien; Le, Tuyen Quang; Park, Hoon Cheol; Byun, Doyoung
2017-05-17
In this paper, we measure unsteady forces and visualize 3D vortices around a beetle-like flapping wing model in hovering flight by experiment and numerical simulation. The measurement of unsteady forces and flow patterns around the wing were conducted using a dynamically scaled wing model in the mineral-oil tank. The wing kinematics were directly derived from the experiment of a real beetle. The 3D flow structures of the flapping wing were captured by using air bubble visualization while forces were measured by a sensor attached at the wing base. In comparison, the size and topology of spiral leading edge vortex, trailing edge vortex and tip vortex are well matched from experimental and numerical studies. In addition, the time history of forces calculated from numerical simulation is also similar to that from theforce measurement. A difference of average force is in order of 10 percent. The results indicate that the leading edge vortex due to rotational acceleration at the end of the stroke during flapping wing causes significant reduction of lift. The present study provides useful information on hover flight to develop a beetle-like flapping wing Micro Air Vehicle.
Global-Local Analysis and Optimization of a Composite Civil Tilt-Rotor Wing
NASA Technical Reports Server (NTRS)
Rais-Rohani, Masound
1999-01-01
This report gives highlights of an investigation on the design and optimization of a thin composite wing box structure for a civil tilt-rotor aircraft. Two different concepts are considered for the cantilever wing: (a) a thin monolithic skin design, and (b) a thick sandwich skin design. Each concept is examined with three different skin ply patterns based on various combinations of 0, +/-45, and 90 degree plies. The global-local technique is used in the analysis and optimization of the six design models. The global analysis is based on a finite element model of the wing-pylon configuration while the local analysis uses a uniformly supported plate representing a wing panel. Design allowables include those on vibration frequencies, panel buckling, and material strength. The design optimization problem is formulated as one of minimizing the structural weight subject to strength, stiffness, and d,vnamic constraints. Six different loading conditions based on three different flight modes are considered in the design optimization. The results of this investigation reveal that of all the loading conditions the one corresponding to the rolling pull-out in the airplane mode is the most stringent. Also the frequency constraints are found to drive the skin thickness limits, rendering the buckling constraints inactive. The optimum skin ply pattern for the monolithic skin concept is found to be (((0/+/-45/90/(0/90)(sub 2))(sub s))(sub s), while for the sandwich skin concept the optimal ply pattern is found to be ((0/+/-45/90)(sub 2s))(sub s).
Inhibition of Shh signalling in the chick wing gives insights into digit patterning and evolution.
Pickering, Joseph; Towers, Matthew
2016-10-01
In an influential model of pattern formation, a gradient of Sonic hedgehog (Shh) signalling in the chick wing bud specifies cells with three antero-posterior positional values, which give rise to three morphologically different digits by a self-organizing mechanism with Turing-like properties. However, as four of the five digits of the mouse limb are morphologically similar in terms of phalangeal pattern, it has been suggested that self-organization alone could be sufficient. Here, we show that inhibition of Shh signalling at a specific stage of chick wing development results in a pattern of four digits, three of which can have the same number of phalanges. These patterning changes are dependent on a posterior extension of the apical ectodermal ridge, and this also allows the additional digit to arise from the Shh-producing cells of the polarizing region - an ability lost in ancestral theropod dinosaurs. Our analyses reveal that, if the specification of antero-posterior positional values is curtailed, self-organization can then produce several digits with the same number of phalanges. We present a model that may give important insights into how the number of digits and phalanges has diverged during the evolution of avian and mammalian limbs. © 2016. Published by The Company of Biologists Ltd.
New Jurassic Hangingflies (Insecta: Mecoptera: Bittacidae) from Inner Mongolia, China.
Liu, Sulin; Shih, Chungkun; Bashkuev, Alexei; Ren, Dong
2016-01-20
A new bittacid genus, Composibittacus gen. nov., with two new species, C. bipunctatus gen. et sp. nov. and C. reticulatus sp. nov., and a new species of Orthobittacus Willmann 1989, O. maculosus sp. nov., are described from the latest Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. Composibittacus gen. nov. has unique wing characters, such as five pterostigmal crossveins between R1 and R2 and R1 and R2+3 and an elongated pterostigma area, which distinguishes it from all other known genera in Bittacidae. Orthobittacus maculosus sp. nov. differs from other species of Orthobittacus by a combination of the following wing characters: M with six branches in forewings and hind wings, two crossveins between C and Sc, and two pterostigmal crossveins in the forewing. In addition, O. maculosus sp. nov. has light-colored or white spots on the fore- and hind wings. These new venational characters of Composibittacus gen. nov. and O. maculosus sp. nov. enhance our understanding of the diverse morphological characters of early hangingflies. Furthermore, based on the striking similarity of the wings of O. maculosus sp. nov. and Juracimbrophlebia ginkgofolia Wang, Labandeira, Shih & Ren 2012 (Cimbrophlebiidae), we propose that leaf mimesis and mutualism with ginkgo plants might have been present in the Bittacidae, as has been proposed in the Cimbrophlebiidae.
Flow structure of vortex-wing interaction
NASA Astrophysics Data System (ADS)
McKenna, Christopher K.
Impingement of a streamwise-oriented vortex upon a fin, tail, blade or wing represents a fundamental class of flow-structure interaction that extends across a range of applications. This interaction can give rise to time-averaged loading, as well as unsteady loading known as buffeting. The loading is sensitive to parameters of the incident vortex as well as the location of vortex impingement on the downstream aerodynamic surface, generically designated as a wing. Particle image velocimetry is employed to determine patterns of velocity, vorticity, swirl ratio, and streamlines on successive cross-flow planes upstream of and along the wing, which lead to volume representations and thereby characterization of the interaction. At locations upstream of the leading edge of the wing, the evolution of the incident vortex is affected by the presence of the wing, and is highly dependent on the spanwise location of vortex impingement. Even at spanwise locations of impingement well outboard of the wing tip, a substantial influence on the structure of the incident vortex at locations significantly upstream of the leading edge of the wing was observed. For spanwise locations close to or intersecting the vortex core, the effects of upstream influence of the wing on the vortex are to: decrease the swirl ratio; increase the streamwise velocity deficit; decrease the streamwise vorticity; increase the azimuthal vorticity; increase the upwash; decrease the downwash; and increase the root-mean-square fluctuations of both streamwise velocity and vorticity. The interrelationship between these effects is addressed, including the rapid attenuation of axial vorticity in presence of an enhanced defect of axial velocity in the central region of the vortex. Moreover, when the incident vortex is aligned with, or inboard of, the tip of the wing, the swirl ratio decreases to values associated with instability of the vortex, giving rise to enhanced values of azimuthal vorticity relative to the streamwise (axial) vorticity, as well as relatively large root-mean-square values of streamwise velocity and vorticity. Along the chord of the wing, the vortex interaction gives rise to distinct modes, which may involve either enhancement or suppression of the vortex generated at the tip of the wing. These modes are classified and interpreted in conjunction with computed modes at the Air Force Research Laboratory. Occurrence of a given mode of interaction is predominantly determined by the dimensionless location of the incident vortex relative to the tip of the wing and is generally insensitive to the Reynolds number and dimensionless circulation of the incident vortex. The genesis of the basic modes of interaction is clarified using streamline topology with associated critical points. Whereas formation of an enhanced tip vortex involves a region of large upwash in conjunction with localized flow separation, complete suppression of the tip vortex is associated with a small-scale separation-attachment bubble bounded by downwash at the wing tip. Oscillation of the wing at an amplitude and velocity nearly two orders of magnitude smaller than the wing chord and free stream velocity respectively can give rise to distinctive patterns of upwash, downwash, and shed vorticity, which are dependent on the outboard displacement of the incident vortex relative to the wing tip. Moreover, these patterns are a strong function of the phase of the wing motion during its oscillation cycle. At a given value of phase, the wing oscillation induces upwash that is reinforced by the upwash of the incident vortex, giving a maximum value of net upwash. Conversely, when these two origins of upwash counteract, rather than reinforce, one another during the oscillation cycle, the net upwash has its minimum value. Analogous interpretations hold for regions of maximum and minimum net downwash located outboard of the regions of upwash. During the oscillation cycle of the wing, the magnitude and scale of the vorticity shed from the tip of the wing are directly correlated with the net upwash, which takes different forms related to the outboard displacement of the incident vortex. As the location of the incident vortex is displaced towards the wing tip, both the maximum upwash and the maximum vorticity of the tip vortex initially increase, then decrease. For the limiting case where the incident vortex impinges directly upon the tip of the wing, there is no tip vortex or induced region of upwash. Furthermore, at small values of vortex displacement from the wing tip, the position of the incident vortex varies significantly from its nominal position during the oscillation cycle. For all locations of the incident vortex, it is shown that, despite the small amplitude of the wing motion, the flow topology is fundamentally different at maximum positive and negative values of the wing velocity, that is, they are not symmetric.
Ennen, Joshua R.; Lindeman, Peter V.; Lovich, Jeffrey E.
2015-01-01
Coloration can play critical roles in a species' biology. The allometry of color patterns may be useful for elucidating the evolutionary mechanisms responsible for shaping the traits. We measured characteristics relating to eight aspects of color patterns from Graptemys oculifera and G. flavimaculata to investigate the allometric differences among male, female, and unsexed juvenile specimens. Additionally, we investigated ontogenetic shifts by incorporating the unsexed juveniles into the male and female datasets. In general, male color traits were isometric (i.e., color scaled with body size), while females and juvenile color traits were hypoallometric, growing in size more slowly than the increase in body size. When we included unsexed juveniles in our male and female datasets, our linear regression analyses found all relationships to be hypoallometric and our model selection analysis found support for nonlinear models describing the relationship between body size and color patterns, suggestive of an ontogenetic shift in coloration traits for both sexes at maturity. Although color is critical for many species' biology and therefore under strong selective pressure in many other species, our results are likely explained by an epiphenomenon related to the different selection pressures on body size and growth rates between juveniles and adults and less attributable to the evolution of color patterns themselves.
Structural dynamics and aerodynamics measurements of biologically inspired flexible flapping wings.
Wu, P; Stanford, B K; Sällström, E; Ukeiley, L; Ifju, P G
2011-03-01
Flapping wing flight as seen in hummingbirds and insects poses an interesting unsteady aerodynamic problem: coupling of wing kinematics, structural dynamics and aerodynamics. There have been numerous studies on the kinematics and aerodynamics in both experimental and computational cases with both natural and artificial wings. These studies tend to ignore wing flexibility; however, observation in nature affirms that passive wing deformation is predominant and may be crucial to the aerodynamic performance. This paper presents a multidisciplinary experimental endeavor in correlating a flapping micro air vehicle wing's aeroelasticity and thrust production, by quantifying and comparing overall thrust, structural deformation and airflow of six pairs of hummingbird-shaped membrane wings of different properties. The results show that for a specific spatial distribution of flexibility, there is an effective frequency range in thrust production. The wing deformation at the thrust-productive frequencies indicates the importance of flexibility: both bending and twisting motion can interact with aerodynamic loads to enhance wing performance under certain conditions, such as the deformation phase and amplitude. By measuring structural deformations under the same aerodynamic conditions, beneficial effects of passive wing deformation can be observed from the visualized airflow and averaged thrust. The measurements and their presentation enable observation and understanding of the required structural properties for a thrust effective flapping wing. The intended passive responses of the different wings follow a particular pattern in correlation to their aerodynamic performance. Consequently, both the experimental technique and data analysis method can lead to further studies to determine the design principles for micro air vehicle flapping wings.
Localised JAK/STAT Pathway Activation Is Required for Drosophila Wing Hinge Development
Johnstone, Kirsty; Wells, Richard E.; Strutt, David; Zeidler, Martin P.
2013-01-01
Extensive morphogenetic remodelling takes place during metamorphosis from a larval to an adult insect body plan. These changes are particularly intricate in the generation of the dipteran wing hinge, a complex structure that is derived from an apparently simple region of the wing imaginal disc. Using the characterisation of original outstretched alleles of the unpaired locus as a starting point, we demonstrate the role of JAK/STAT pathway signalling in the process of wing hinge development. We show that differences in JAK/STAT signalling within the proximal most of three lateral folds present in the wing imaginal disc is required for fold morphology and the subsequent differentiation of the first and second auxiliary sclerites as well as the posterior notal wing process. Changes in these domains are consistent with the established fate map of the wing disc. We show that outstretched wing posture phenotypes arise from the loss of a region of Unpaired expression in the proximal wing fold and demonstrate that this results in a decrease in JAK/STAT pathway activity. Finally we show that reduction of JAK/STAT pathway activity within the proximal wing fold is sufficient to phenocopy the outstretched phenotype. Taken together, we suggest that localised Unpaired expression and hence JAK/STAT pathway activity, is required for the morphogenesis of the adult wing hinge, providing new insights into the link between signal transduction pathways, patterning and development. PMID:23741461
Husak, J F; Ribak, G; Baker, R H; Rivera, G; Wilkinson, G S; Swallow, J G
2013-06-01
Exaggerated male ornaments are predicted to be costly to their bearers, but these negative effects may be offset by the correlated evolution of compensatory traits. However, when locomotor systems, such as wings in flying species, evolve to decrease such costs, it remains unclear whether functional changes across related species are achieved via the same morphological route or via alternate changes that have similar function. We conducted a comparative analysis of wing shape in relation to eye-stalk elongation across 24 species of stalk-eyed flies, using geometric morphometrics to determine how species with increased eye span, a sexually selected trait, have modified wing morphology as a compensatory mechanism. Using traditional and phylogenetically informed multivariate analyses of shape in combination with phenotypic trajectory analysis, we found a strong phylogenetic signal in wing shape. However, dimorphic species possessed shifted wing veins with the result of lengthening and narrowing wings compared to monomorphic species. Dimorphic species also had changes that seem unrelated to wing size, but instead may govern wing flexion. Nevertheless, the lack of a uniform, compensatory pattern suggests that stalk-eyed flies used alternative modifications in wing structure to increase wing area and aspect ratio, thus taking divergent morphological routes to compensate for exaggerated eye stalks. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.
Volumetric display containing multiple two-dimensional color motion pictures
NASA Astrophysics Data System (ADS)
Hirayama, R.; Shiraki, A.; Nakayama, H.; Kakue, T.; Shimobaba, T.; Ito, T.
2014-06-01
We have developed an algorithm which can record multiple two-dimensional (2-D) gradated projection patterns in a single three-dimensional (3-D) object. Each recorded pattern has the individual projected direction and can only be seen from the direction. The proposed algorithm has two important features: the number of recorded patterns is theoretically infinite and no meaningful pattern can be seen outside of the projected directions. In this paper, we expanded the algorithm to record multiple 2-D projection patterns in color. There are two popular ways of color mixing: additive one and subtractive one. Additive color mixing used to mix light is based on RGB colors and subtractive color mixing used to mix inks is based on CMY colors. We made two coloring methods based on the additive mixing and subtractive mixing. We performed numerical simulations of the coloring methods, and confirmed their effectiveness. We also fabricated two types of volumetric display and applied the proposed algorithm to them. One is a cubic displays constructed by light-emitting diodes (LEDs) in 8×8×8 array. Lighting patterns of LEDs are controlled by a microcomputer board. The other one is made of 7×7 array of threads. Each thread is illuminated by a projector connected with PC. As a result of the implementation, we succeeded in recording multiple 2-D color motion pictures in the volumetric displays. Our algorithm can be applied to digital signage, media art and so forth.
Human preferences for colorful birds: Vivid colors or pattern?
Lišková, Silvie; Landová, Eva; Frynta, Daniel
2015-04-29
In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern), and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.
Biomimetics, color, and the arts
NASA Astrophysics Data System (ADS)
Schenk, Franziska
2015-03-01
Color as dramatic, dynamic and dazzling as the iridescent hues on the wings of certain butterflies has never been encountered in the art world. Unlike and unmatched by the chemical pigments of the artists' palette, this changeable color is created by transparent, colorless nanostructures that, as with prisms, diffract and reflect light to render spectral color visible. Until now, iridescent colors, by their very nature, have defied artists' best efforts to fully capture these rainbow hues. Now, for the first time, the artist and researcher Franziska Schenk employs latest nature-inspired color-shift technology to actually simulate the iridescence of butterflies and beetles on canvas. Crucially, studying the ingenious ways in which a range of such displays are created by insects has provided the artist with vital clues on how to adapt and adopt these challenging optical nano-materials for painting. And indeed, after years of meticulous and painstaking research both in the lab and studio, the desired effect is achieved. The resulting paintings, like an iridescent insect, do in fact fluctuate in perceived color - depending on the light and viewing angle. In tracing the artist's respective biomimetic approach, the paper not only provides an insight into the new color technology's evolution and innovative artistic possibilities, but also suggests what artists can learn from nature.
Fric, Z; Konvicka, M; Zrzavy, J
2004-03-01
Phylogeny of the butterfly genera Araschnia, Mynes, Symbrenthia and Brensymthia (Lepidoptera: Nymphalidae: Nymphalini) is reconstructed, based on 140 morphological and ecological characters. The resulting tree shows that Araschnia is a sister group of the clade including Symbrenthia, Mynes and Brensymthia (Symbrenthia is paraphyletic in the respect of remaining genera; Symbrenthia hippalus is a derived species of Mynes). The species-level relationships within Araschnia are robustly supported as follows: (A. davidis (prorsoides ((zhangi doris) (dohertyi (levana burejana))))). Analysis of the wing colour-pattern characters linked with the seasonal polyphenism in the Araschnia species suggests that the black and white coloration of the long-day (summer) generation is apomorphic. Biogeographically, the origin of polyphenism in Araschnia predates the dispersal of some Araschnia species towards the Palaearctic temperate zone, and the ecological cause of the polyphenism itself is then probably not linked with thermoregulation. The possible mimetic/cryptic scenarios for the origin of Araschnia polyphenism are discussed.
Shang, Shenglong; Zhang, Qinghong; Wang, Hongzhi; Li, Yaogang
2017-01-01
A flexible, magnetic field induced structurally colored films with brilliant colors and high physical rigidity were reported in this article. Using an external magnetic field, the photocurable colloidal suspensions that containing superparamagnetic Fe 3 O 4 @C colloidal nanocrystal clusters (CNCs) could polymerize under UV light. After polymerization, the films with different colors (red, green, blue) were obtained. Through combination of suspensions which contains Fe 3 O 4 @C CNCs with different sizes, a series of multi-colored films were obtained. Moreover, these structural colors can be patterned easily by photolithography and various structural colored patterns were shown in the article. The structural colored patterns could conceal or display its color according to the changing of background which makes them hold significant potential applications for security materials. Copyright © 2016 Elsevier Inc. All rights reserved.
Molecular patterns of X chromosome-linked color vision genes among 134 menof European ancestry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Drummond-Borg, M.; Deeb, S.S.; Motulsky, A.G.
1989-02-01
The authors used Southern blot hybridization to study X chromosome-linked color vision genes encoding the apoproteins of red and green visual pigments in 134 unselected Caucasian men. One hundred and thirteen individuals (84.3%) had a normal arrangement of their color vision pigment genes. All had one red pigment gene; the number of green pigment genes ranged from one to five with a mode of two. The frequency of molecular genotypes indicative of normal color vision (84.3%) was significantly lower than had been observed in previous studies of color vision phenotypes. Color vision defects can be due to deletions of redmore » or green pigment genes or due to formation of hybrid genes comprising portions of both red and green pigment genes. Characteristic anomalous patterns were seen in 15 (11.2%) individuals: 7 (5.2%) had patterns characteristic of deuteranomaly, 2 (1.5%) had patterns characteristic of deuteranopia, and 6 (4.5%) had protan patterns. Previously undescribed hybrid gene patterns consisting of both green and red pigment gene fragments in addition to normal red and green genes were observed in another 6 individuals (4.5%). Thus, DNA testing detected anomalous color vision pigment genes at a higher frequency than expected from phenotypic color vision tests.« less
Dai, Mengyao; Wang, Yao; Fang, Lu; Irwin, David M; Zhu, Tengteng; Zhang, Junpeng; Zhang, Shuyi; Wang, Zhe
2014-01-01
Bats are the only mammals capable of self-powered flight using wings. Differing from mouse or human limbs, four elongated digits within a broad wing membrane support the bat wing, and the foot of the bat has evolved a long calcar that spread the interfemoral membrane. Our recent mRNA sequencing (mRNA-Seq) study found unique expression patterns for genes at the 5' end of the Hoxd gene cluster and for Tbx3 that are associated with digit elongation and wing membrane growth in bats. In this study, we focused on two additional genes, Meis2 and Mab21l2, identified from the mRNA-Seq data. Using whole-mount in situ hybridization (WISH) we validated the mRNA-Seq results for differences in the expression patterns of Meis2 and Mab21l2 between bat and mouse limbs, and further characterize the timing and location of the expression of these two genes. These analyses suggest that Meis2 may function in wing membrane growth and Mab21l2 may have a role in AP and DV axial patterning. In addition, we found that Tbx3 is uniquely expressed in the unique calcar structure found in the bat hindlimb, suggesting a role for this gene in calcar growth and elongation. Moreover, analysis of the coding sequences for Meis2, Mab21l2 and Tbx3 showed that Meis2 and Mab21l2 have high sequence identity, consistent with the functions of genes being conserved, but that Tbx3 showed accelerated evolution in bats. However, evidence for positive selection in Tbx3 was not found, which would suggest that the function of this gene has not been changed. Together, our findings support the hypothesis that the modulation of the spatiotemporal expression patterns of multiple functional conserved genes control limb morphology and drive morphological change in the diversification of mammalian limbs.
Fang, Lu; Irwin, David M.; Zhu, Tengteng; Zhang, Junpeng; Zhang, Shuyi; Wang, Zhe
2014-01-01
Bats are the only mammals capable of self-powered flight using wings. Differing from mouse or human limbs, four elongated digits within a broad wing membrane support the bat wing, and the foot of the bat has evolved a long calcar that spread the interfemoral membrane. Our recent mRNA sequencing (mRNA-Seq) study found unique expression patterns for genes at the 5′ end of the Hoxd gene cluster and for Tbx3 that are associated with digit elongation and wing membrane growth in bats. In this study, we focused on two additional genes, Meis2 and Mab21l2, identified from the mRNA-Seq data. Using whole-mount in situ hybridization (WISH) we validated the mRNA-Seq results for differences in the expression patterns of Meis2 and Mab21l2 between bat and mouse limbs, and further characterize the timing and location of the expression of these two genes. These analyses suggest that Meis2 may function in wing membrane growth and Mab21l2 may have a role in AP and DV axial patterning. In addition, we found that Tbx3 is uniquely expressed in the unique calcar structure found in the bat hindlimb, suggesting a role for this gene in calcar growth and elongation. Moreover, analysis of the coding sequences for Meis2, Mab21l2 and Tbx3 showed that Meis2 and Mab21l2 have high sequence identity, consistent with the functions of genes being conserved, but that Tbx3 showed accelerated evolution in bats. However, evidence for positive selection in Tbx3 was not found, which would suggest that the function of this gene has not been changed. Together, our findings support the hypothesis that the modulation of the spatiotemporal expression patterns of multiple functional conserved genes control limb morphology and drive morphological change in the diversification of mammalian limbs. PMID:25166052
Lehmann, Fritz-Olaf; Pick, Simon
2007-04-01
Flying insects may enhance their flight force production by contralateral wing interaction during dorsal stroke reversal ('clap-and-fling'). In this study, we explored the forces and moments due to clap-and-fling at various wing tip trajectories, employing a dynamically scaled electromechanical flapping device. The 17 tested bio-inspired kinematic patterns were identical in stroke amplitude, stroke frequency and angle of attack with respect to the horizontal stroke plane but varied in heaving motion. Clap-and-fling induced vertical force augmentation significantly decreased with increasing vertical force production averaged over the entire stroke cycle, whereas total force augmentation was independent from changes in force produced by a single wing. Vertical force augmentation was also largely independent of forces produced due to wing rotation at the stroke reversals, the sum of rotational circulation and wake capture force. We obtained maximum (17.4%) and minimum (1.4%) vertical force augmentation in two types of figure-eight stroke kinematics whereby rate and direction of heaving motion during fling may explain 58% of the variance in vertical force augmentation. This finding suggests that vertical wing motion distinctly alters the flow regime at the beginning of the downstroke. Using an analytical model, we determined pitching moments acting on an imaginary body of the flapping device from the measured time course of forces, the changes in length of the force vector's moment arm, the position of the centre of mass and body angle. The data show that pitching moments are largely independent from mean vertical force; however, clap-and-fling reinforces mean pitching moments by approximately 21%, compared to the moments produced by a single flapping wing. Pitching moments due to clap-and-fling significantly increase with increasing vertical force augmentation and produce nose-down moments in most of the tested patterns. The analytical model, however, shows that algebraic sign and magnitude of these moments may vary distinctly depending on both body angle and the distance between the wing hinge and the animal's centre of mass. Altogether, the data suggest that the benefit of clap-and-fling wing beat for vertical force enhancement and pitch balance may change with changing heaving motion and thus wing tip trajectory during manoeuvring flight. We hypothesize that these dependencies may have shaped the evolution of wing kinematics in insects that are limited by aerodynamic lift rather than by mechanical power of their flight musculature.
Oh, Paul; Lee, Sukho; Kang, Moon Gi
2017-01-01
Recently, several RGB-White (RGBW) color filter arrays (CFAs) have been proposed, which have extra white (W) pixels in the filter array that are highly sensitive. Due to the high sensitivity, the W pixels have better SNR (Signal to Noise Ratio) characteristics than other color pixels in the filter array, especially, in low light conditions. However, most of the RGBW CFAs are designed so that the acquired RGBW pattern image can be converted into the conventional Bayer pattern image, which is then again converted into the final color image by using conventional demosaicing methods, i.e., color interpolation techniques. In this paper, we propose a new RGBW color filter array based on a totally different color interpolation technique, the colorization algorithm. The colorization algorithm was initially proposed for colorizing a gray image into a color image using a small number of color seeds. Here, we adopt this algorithm as a color interpolation technique, so that the RGBW color filter array can be designed with a very large number of W pixels to make the most of the highly sensitive characteristics of the W channel. The resulting RGBW color filter array has a pattern with a large proportion of W pixels, while the small-numbered RGB pixels are randomly distributed over the array. The colorization algorithm makes it possible to reconstruct the colors from such a small number of RGB values. Due to the large proportion of W pixels, the reconstructed color image has a high SNR value, especially higher than those of conventional CFAs in low light condition. Experimental results show that many important information which are not perceived in color images reconstructed with conventional CFAs are perceived in the images reconstructed with the proposed method. PMID:28657602
Oh, Paul; Lee, Sukho; Kang, Moon Gi
2017-06-28
Recently, several RGB-White (RGBW) color filter arrays (CFAs) have been proposed, which have extra white (W) pixels in the filter array that are highly sensitive. Due to the high sensitivity, the W pixels have better SNR (Signal to Noise Ratio) characteristics than other color pixels in the filter array, especially, in low light conditions. However, most of the RGBW CFAs are designed so that the acquired RGBW pattern image can be converted into the conventional Bayer pattern image, which is then again converted into the final color image by using conventional demosaicing methods, i.e., color interpolation techniques. In this paper, we propose a new RGBW color filter array based on a totally different color interpolation technique, the colorization algorithm. The colorization algorithm was initially proposed for colorizing a gray image into a color image using a small number of color seeds. Here, we adopt this algorithm as a color interpolation technique, so that the RGBW color filter array can be designed with a very large number of W pixels to make the most of the highly sensitive characteristics of the W channel. The resulting RGBW color filter array has a pattern with a large proportion of W pixels, while the small-numbered RGB pixels are randomly distributed over the array. The colorization algorithm makes it possible to reconstruct the colors from such a small number of RGB values. Due to the large proportion of W pixels, the reconstructed color image has a high SNR value, especially higher than those of conventional CFAs in low light condition. Experimental results show that many important information which are not perceived in color images reconstructed with conventional CFAs are perceived in the images reconstructed with the proposed method.
Lokemoen, John T.; Johnson, Douglas H.; Sharp, David E.
1990-01-01
During 1976-81 we weighed several thousands of wild Mallard, Gadwall, and Blue-winged Teal in central North Dakota to examine duckling growth patterns, adult weights, and the factors influencing them. One-day-old Mallard and Gadwall averaged 32.4 and 30.4 g, respectively, a reduction of 34% and 29% from fresh egg weights. In all three species, the logistic growth curve provided a good fit for duckling growth patterns. Except for the asymptote, there was no difference in growth curves between males and females of a species. Mallard and Gadwall ducklings were heavier in years when wetland area was extensive or had increased from the previous year. Weights of after-second-year females were greater than yearlings for Mallard but not for Gadwall or Blue-winged Teal. Adult Mallard females lost weight continuously from late March to early July. Gadwall and Blue-winged Teal females, which nest later than Mallard, gained weight after spring arrival, lost weight from the onset of nesting until early July, and then regained some weight. Females of all species captured on nests were lighter than those captured off nests at the same time. Male Mallard weights decreased from spring arrival until late May. Male Gadwall and Blue-winged Teal weights increased after spring arrival, then declined until early June. Males of all three species then gained weight until the end of June. Among adults, female Gadwall and male Mallard and Blue-winged Teal were heavier in years when wetland area had increased from the previous year; female Blue-winged Teal were heavier in years with more wetland area.
Nattero, Julieta; Dujardin, Jean-Pierre; Del Pilar Fernández, María; Gürtler, Ricardo E
2015-12-01
Fluctuating asymmetry (FA), a slight and random departure from bilateral symmetry that is normally distributed around a 0 mean, has been widely used to infer developmental instability. We investigated whether habitats (ecotopes) and host-feeding sources influenced wing FA of the hematophagous bug Triatoma infestans. Because bug populations occupying distinct habitats differed substantially and consistently in various aspects such as feeding rates, engorgement status and the proportion of gravid females, we predicted that bugs from more open peridomestic habitats (i.e., goat corrals) were more likely to exhibit higher FA than bugs from domiciles. We examined patterns of asymmetry and the amount of wing size and shape FA in 196 adult T. infestans collected across a gradient of habitat suitability and stability that decreased from domiciles, storerooms, kitchens, chicken coops, pig corrals, to goat corrals in a well-defined area of Figueroa, northwestern Argentina. The bugs had unmixed blood meals on human, chicken, pig and goat depending on the bug collection ecotope. We documented the occurrence of FA in wing shape for bugs fed on all host-feeding sources and in all ecotopes except for females from domiciles or fed on humans. FA indices for wing shape differed significantly among host-feeding sources, ecotopes and sexes. The patterns of wing asymmetry in females from domiciles and from goat corrals were significantly different; differences in male FA were congruent with evidence showing that they had higher mobility than females across habitats. The host-feeding sources and habitats of T. infestans affected wing developmental stability depending on sex. Copyright © 2015 Elsevier B.V. All rights reserved.
Estimation of color modification in digital images by CFA pattern change.
Choi, Chang-Hee; Lee, Hae-Yeoun; Lee, Heung-Kyu
2013-03-10
Extensive studies have been carried out for detecting image forgery such as copy-move, re-sampling, blurring, and contrast enhancement. Although color modification is a common forgery technique, there is no reported forensic method for detecting this type of manipulation. In this paper, we propose a novel algorithm for estimating color modification in images acquired from digital cameras when the images are modified. Most commercial digital cameras are equipped with a color filter array (CFA) for acquiring the color information of each pixel. As a result, the images acquired from such digital cameras include a trace from the CFA pattern. This pattern is composed of the basic red green blue (RGB) colors, and it is changed when color modification is carried out on the image. We designed an advanced intermediate value counting method for measuring the change in the CFA pattern and estimating the extent of color modification. The proposed method is verified experimentally by using 10,366 test images. The results confirmed the ability of the proposed method to estimate color modification with high accuracy. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Single-shot real-time three dimensional measurement based on hue-height mapping
NASA Astrophysics Data System (ADS)
Wan, Yingying; Cao, Yiping; Chen, Cheng; Fu, Guangkai; Wang, Yapin; Li, Chengmeng
2018-06-01
A single-shot three-dimensional (3D) measurement based on hue-height mapping is proposed. The color fringe pattern is encoded by three sinusoidal fringes with the same frequency but different shifting phase into red (R), green (G) and blue (B) color channels, respectively. It is found that the hue of the captured color fringe pattern on the reference plane maintains monotonic in one period even it has the color crosstalk. Thus, unlike the traditional color phase shifting technique, the hue information is utilized to decode the color fringe pattern and map to the pixels of the fringe displacement in the proposed method. Because the monotonicity of the hue is limited within one period, displacement unwrapping is proposed to obtain the continuous displacement that is finally used to map to the height distribution. This method directly utilizes the hue under the effect of color crosstalk for mapping the height so that no color calibration is involved. Also, as it requires only single shot deformed color fringe pattern, this method can be applied into the real-time or dynamic 3D measurements.
ERIC Educational Resources Information Center
Nelken, Miranda
2010-01-01
This article presents a lesson that allows students to make bird ornaments using a metal tooling as it can be textured, cut, and colored. In this lesson, students choose a bird and sketch it on a piece of paper. Once the sketches are complete, students copy their pictures on a second piece of paper by taping the sketch over a sheet of blank paper…
ERIC Educational Resources Information Center
Malone, Molly
2012-01-01
Most middle school students comprehend that organisms have adaptations that enable their survival and that successful adaptations prevail in a population over time. Yet they often miss that those bird beaks, moth-wing colors, or whatever traits are the result of random, normal genetic variations that just happen to confer a negative, neutral, or…
Murillo-Maldonado, Juan M; Zeineddine, Fouad Bou; Stock, Rachel; Thackeray, Justin; Riesgo-Escovar, Juan R
2011-01-01
Coordination between growth and patterning/differentiation is critical if appropriate final organ structure and size is to be achieved. Understanding how these two processes are regulated is therefore a fundamental and as yet incompletely answered question. Here we show through genetic analysis that the phospholipase C-γ (PLC-γ) encoded by small wing (sl) acts as such a link between growth and patterning/differentiation by modulating some MAPK outputs once activated by the insulin pathway; particularly, sl promotes growth and suppresses ectopic differentiation in the developing eye and wing, allowing cells to attain a normal size and differentiate properly. sl mutants have previously been shown to have a combination of both growth and patterning/differentiation phenotypes: small wings, ectopic wing veins, and extra R7 photoreceptor cells. We show here that PLC-γ activated by the insulin pathway participates broadly and positively during cell growth modulating EGF pathway activity, whereas in cell differentiation PLC-γ activated by the insulin receptor negatively regulates the EGF pathway. These roles require different SH2 domains of PLC-γ, and act via classic PLC-γ signaling and EGF ligand processing. By means of PLC-γ, the insulin receptor therefore modulates differentiation as well as growth. Overall, our results provide evidence that PLC-γ acts during development at a time when growth ends and differentiation begins, and is important for proper coordination of these two processes.
Novel method for measuring a dense 3D strain map of robotic flapping wings
NASA Astrophysics Data System (ADS)
Li, Beiwen; Zhang, Song
2018-04-01
Measuring dense 3D strain maps of the inextensible membranous flapping wings of robots is of vital importance to the field of bio-inspired engineering. Conventional high-speed 3D videography methods typically reconstruct the wing geometries through measuring sparse points with fiducial markers, and thus cannot obtain the full-field mechanics of the wings in detail. In this research, we propose a novel system to measure a dense strain map of inextensible membranous flapping wings by developing a superfast 3D imaging system and a computational framework for strain analysis. Specifically, first we developed a 5000 Hz 3D imaging system based on the digital fringe projection technique using the defocused binary patterns to precisely measure the dynamic 3D geometries of rapidly flapping wings. Then, we developed a geometry-based algorithm to perform point tracking on the precisely measured 3D surface data. Finally, we developed a dense strain computational method using the Kirchhoff-Love shell theory. Experiments demonstrate that our method can effectively perform point tracking and measure a highly dense strain map of the wings without many fiducial markers.
Color filter array design based on a human visual model
NASA Astrophysics Data System (ADS)
Parmar, Manu; Reeves, Stanley J.
2004-05-01
To reduce cost and complexity associated with registering multiple color sensors, most consumer digital color cameras employ a single sensor. A mosaic of color filters is overlaid on a sensor array such that only one color channel is sampled per pixel location. The missing color values must be reconstructed from available data before the image is displayed. The quality of the reconstructed image depends fundamentally on the array pattern and the reconstruction technique. We present a design method for color filter array patterns that use red, green, and blue color channels in an RGB array. A model of the human visual response for luminance and opponent chrominance channels is used to characterize the perceptual error between a fully sampled and a reconstructed sparsely-sampled image. Demosaicking is accomplished using Wiener reconstruction. To ensure that the error criterion reflects perceptual effects, reconstruction is done in a perceptually uniform color space. A sequential backward selection algorithm is used to optimize the error criterion to obtain the sampling arrangement. Two different types of array patterns are designed: non-periodic and periodic arrays. The resulting array patterns outperform commonly used color filter arrays in terms of the error criterion.
Chiao, Chuan-Chin; Wickiser, J Kenneth; Allen, Justine J; Genter, Brock; Hanlon, Roger T
2011-05-31
Camouflage is a widespread phenomenon throughout nature and an important antipredator tactic in natural selection. Many visual predators have keen color perception, and thus camouflage patterns should provide some degree of color matching in addition to other visual factors such as pattern, contrast, and texture. Quantifying camouflage effectiveness in the eyes of the predator is a challenge from the perspectives of both biology and optical imaging technology. Here we take advantage of hyperspectral imaging (HSI), which records full-spectrum light data, to simultaneously visualize color match and pattern match in the spectral and the spatial domains, respectively. Cuttlefish can dynamically camouflage themselves on any natural substrate and, despite their colorblindness, produce body patterns that appear to have high-fidelity color matches to the substrate when viewed directly by humans or with RGB images. Live camouflaged cuttlefish on natural backgrounds were imaged using HSI, and subsequent spectral analysis revealed that most reflectance spectra of individual cuttlefish and substrates were similar, rendering the color match possible. Modeling color vision of potential di- and trichromatic fish predators of cuttlefish corroborated the spectral match analysis and demonstrated that camouflaged cuttlefish show good color match as well as pattern match in the eyes of fish predators. These findings (i) indicate the strong potential of HSI technology to enhance studies of biological coloration and (ii) provide supporting evidence that cuttlefish can produce color-coordinated camouflage on natural substrates despite lacking color vision.
Facial Recognition in a Discus Fish (Cichlidae): Experimental Approach Using Digital Models
Satoh, Shun; Tanaka, Hirokazu; Kohda, Masanori
2016-01-01
A number of mammals and birds are known to be capable of visually discriminating between familiar and unfamiliar individuals, depending on facial patterns in some species. Many fish also visually recognize other conspecifics individually, and previous studies report that facial color patterns can be an initial signal for individual recognition. For example, a cichlid fish and a damselfish will use individual-specific color patterns that develop only in the facial area. However, it remains to be determined whether the facial area is an especially favorable site for visual signals in fish, and if so why? The monogamous discus fish, Symphysopdon aequifasciatus (Cichlidae), is capable of visually distinguishing its pair-partner from other conspecifics. Discus fish have individual-specific coloration patterns on entire body including the facial area, frontal head, trunk and vertical fins. If the facial area is an inherently important site for the visual cues, this species will use facial patterns for individual recognition, but otherwise they will use patterns on other body parts as well. We used modified digital models to examine whether discus fish use only facial coloration for individual recognition. Digital models of four different combinations of familiar and unfamiliar fish faces and bodies were displayed in frontal and lateral views. Focal fish frequently performed partner-specific displays towards partner-face models, and did aggressive displays towards models of non-partner’s faces. We conclude that to identify individuals this fish does not depend on frontal color patterns but does on lateral facial color patterns, although they have unique color patterns on the other parts of body. We discuss the significance of facial coloration for individual recognition in fish compared with birds and mammals. PMID:27191162
Facial Recognition in a Discus Fish (Cichlidae): Experimental Approach Using Digital Models.
Satoh, Shun; Tanaka, Hirokazu; Kohda, Masanori
2016-01-01
A number of mammals and birds are known to be capable of visually discriminating between familiar and unfamiliar individuals, depending on facial patterns in some species. Many fish also visually recognize other conspecifics individually, and previous studies report that facial color patterns can be an initial signal for individual recognition. For example, a cichlid fish and a damselfish will use individual-specific color patterns that develop only in the facial area. However, it remains to be determined whether the facial area is an especially favorable site for visual signals in fish, and if so why? The monogamous discus fish, Symphysopdon aequifasciatus (Cichlidae), is capable of visually distinguishing its pair-partner from other conspecifics. Discus fish have individual-specific coloration patterns on entire body including the facial area, frontal head, trunk and vertical fins. If the facial area is an inherently important site for the visual cues, this species will use facial patterns for individual recognition, but otherwise they will use patterns on other body parts as well. We used modified digital models to examine whether discus fish use only facial coloration for individual recognition. Digital models of four different combinations of familiar and unfamiliar fish faces and bodies were displayed in frontal and lateral views. Focal fish frequently performed partner-specific displays towards partner-face models, and did aggressive displays towards models of non-partner's faces. We conclude that to identify individuals this fish does not depend on frontal color patterns but does on lateral facial color patterns, although they have unique color patterns on the other parts of body. We discuss the significance of facial coloration for individual recognition in fish compared with birds and mammals.
Microscopic modulation of mechanical properties in transparent insect wings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arora, Ashima; Kumar, Pramod; Bhagavathi, Jithin
We report on the measurement of local friction and adhesion of transparent insect wings using an atomic force microscope cantilever down to nanometre length scales. We observe that the wing-surface is decorated with 10 μm long and 2 μm wide islands that have higher topographic height. The friction on the islands is two orders of magnitude higher than the back-ground while the adhesion on the islands is smaller. Furthermore, the high islands are decorated with ordered nano-wire-like structures while the background is full of randomly distributed granular nano-particles. Coherent optical diffraction through the wings produce a stable diffraction pattern revealing a quasi-periodicmore » organization of the high islands over the entire wing. This suggests a long-range order in the modulation of friction and adhesion which is directly correlated with the topography. The measurements unravel novel functional design of complex wing surface and could find application in miniature biomimetic devices.« less
Replication of cicada wing's nano-patterns by hot embossing and UV nanoimprinting.
Hong, Sung-Hoon; Hwang, Jaeyeon; Lee, Heon
2009-09-23
The hydrophobicity of the cicada wing originates from its naturally occurring, surface nano-structure. The nano-structure of the cicada wing consists of an array of nano-sized pillars, 100 nm in diameter and 300 nm in height. In this study, the nano-structure of the cicada wing was successfully duplicated by using hot embossing lithography and UV nanoimprint lithography (NIL). The diameter and pitch of replication were the same as those of the original cicada wing and the height was a little smaller than that of the original master. The transmittance of the hot embossed PVC film was increased by 2-6% compared with that of the bare PVC film. The hydrophobicity was measured by water contact angle measurements. The water contact angle of the replica, made of UV cured polymer, was 132 degrees +/- 2 degrees , which was slightly lower than that of the original cicada wing (138 degrees +/- 2 degrees ), but much higher than that of the UV cured polymer surface without any nano-sized pillars (86 degrees ).
Analysis of the skin transcriptome in two oujiang color varieties of common carp.
Wang, Chenghui; Wachholtz, Michael; Wang, Jun; Liao, Xiaolin; Lu, Guoqing
2014-01-01
Body color and coloration patterns are important phenotypic traits to maintain survival and reproduction activities. The Oujiang color varieties of common carp (Cyprinus carpio var. color), with a narrow distribution in Zhejiang Province of China and a history of aquaculture for over 1,200 years, consistently exhibit a variety of body color patterns. The molecular mechanism underlying diverse color patterns in these variants is unknown. To the practical end, it is essential to develop molecular markers that can distinguish different phenotypes and assist selective breeding. In this exploratory study, we conducted Roche 454 transcriptome sequencing of two pooled skin tissue samples of Oujiang common carp, which correspond to distinct color patterns, red with big black spots (RB) and whole white (WW), and a total of 737,525 sequence reads were generated. The reads obtained in this study were co-assembled jointly with common carp Roche 454 sequencing reads downloaded from NCBI SRA database, resulting in 43,923 isotigs and 546,676 singletons. Over 31 thousand (31,445; 71.6%) isotigs were found with significant BLAST matches (E<1e-10) to the nr protein database, which corresponds to 12,597 annotated zebrafish genes. A total of 70,947 isotigs and singletons (transcripts) were annotated with Gene Ontology, and 60,221 transcripts were found with corresponding EC numbers. Out of 145 zebrafish pigmentation genes, orthologs for 117 were recovered in Oujiang color carp transcriptome, including 18 found only among singletons. Our transcriptome analysis revealed over 52,902 SNPs in Oujiang common carp, and identified 63 SNP markers that are putatively unique either for RB or WW. The transcriptome of Oujiang color varieties of common carp obtained through this study, along with the pigmentation genes recovered and the color pattern-specific molecular markers developed, will facilitate future research on the molecular mechanism of color patterns and promote aquaculture of Oujiang color varieties of common carp through molecular marker assisted-selective breeding.
An experimental study of mushroom shaped stall cells. [on finite wings with separated flow
NASA Technical Reports Server (NTRS)
Winkelmann, A. E.
1982-01-01
Surface patterns characterized by a pair of counter-rotating swirls have been observed in connection with the conduction of surface flow visualization experiments involving test geometries with separated flows. An example of this phenomenon occurring on a finite wing with trailing edge stall has been referred to by Winkelmann and Barlow (1980) as 'mushroom shaped'. A description is presented of a collection of experimental results which show or suggest the occurrence of mushroom shaped stall cells on a variety of test geometries. Investigations conducted with finite wings, airfoil models, and flat plates are considered, and attention is given to studies involving the use of bluff models, investigations of shock induced boundary layer separation, and mushroom shaped patterns observed in a number of miscellaneous cases. It is concluded that the mushroom shaped stall cell appears commonly in separated flow regions.
Stitch overlap via coloring technique enables maskless via
NASA Astrophysics Data System (ADS)
Civay, D.; Laffosse, E.
2017-03-01
Lithographic patterning limits can be a cost-barrier that delays advancement to new nodes. This paper introduces a cost-saving design method that enables a maskless via. Multi-patterning or coloring of a design is a technique that is used at advanced nodes to aid in patterning. Coloring allows designers to designate different patterns on one level to be printed with different masks. Stitch overlap via (SOV) is a coloring technique introduced herein. SOV utilizes via-aware coloring and a unique process flow to print a maskless via. Identification of qualifying design structures is achieved through a custom program. The program inputs the design level of the multipatterned layer and the via levels above and below to determine the coloring decomposition. Vias are a particularly challenging layer to print due to the dimensions required for these pillars. SOV is a methodology for identifying qualifying multi-patterned layouts and replacing them with a new design that enables a maskless via layer.
NASA Technical Reports Server (NTRS)
Erickson, Gary E.
1991-01-01
The vortex dominated aerodynamic characteristics of a generic 65 degree cropped delta wing model were studied in a wind tunnel at subsonic through supersonic speeds. The lee-side flow fields over the wing-alone configuration and the wing with leading edge extension (LEX) added were observed at M (infinity) equals 0.40 to 1.60 using a laser vapor screen technique. These results were correlated with surface streamline patterns, upper surface static pressure distributions, and six-component forces and moments. The wing-alone exhibited vortex breakdown and asymmetry of the breakdown location at the subsonic and transonic speeds. An earlier onset of vortex breakdown over the wing occurred at transonic speeds due to the interaction of the leading edge vortex with the normal shock wave. The development of a shock wave between the vortex and wing surface caused an early separation of the secondary boundary layer. With the LEX installed, wing vortex breakdown asymmetry did not occur up to the maximum angle of attack in the present test of 24 degrees. The favorable interaction of the LEX vortex with the wing flow field reduced the effects of shock waves on the wing primary and secondary vortical flows. The direct interaction of the wing and LEX vortex cores diminished with increasing Mach number. The maximum attainable vortex-induced pressure signatures were constrained by the vacuum pressure limit at the transonic and supersonic speeds.
In situ protocol for butterfly pupal wings using riboprobes.
Ramos, Diane; Monteiro, Antonia
2007-01-01
Here we present, in video format, a protocol for in situ hybridizations in pupal wings of the butterfly Bicyclus anynana using riboprobes. In situ hybridizations, a mainstay of developmental biology, are useful to study the spatial and temporal patterns of gene expression in developing tissues at the level of transcription. If antibodies that target the protein products of gene transcription have not yet been developed, and/or there are multiple gene copies of a particular protein in the genome that cannot be differentiated using available antibodies, in situs can be used instead. While an in situ technique for larval wing discs has been available to the butterfly community for several years, the current protocol has been optimized for the larger and more fragile pupal wings.
Boundary Dpp promotes growth of medial and lateral regions of the Drosophila wing.
Barrio, Lara; Milán, Marco
2017-07-04
The gradient of Decapentaplegic (Dpp) in the Drosophila wing has served as a paradigm to characterize the role of morphogens in regulating patterning. However, the role of this gradient in regulating tissue size is a topic of intense debate as proliferative growth is homogenous. Here, we combined the Gal4/UAS system and a temperature-sensitive Gal80 molecule to induce RNAi-mediated depletion of dpp and characterise the spatial and temporal requirement of Dpp in promoting growth. We show that Dpp emanating from the AP compartment boundary is required throughout development to promote growth by regulating cell proliferation and tissue size. Dpp regulates growth and proliferation rates equally in central and lateral regions of the developing wing appendage and reduced levels of Dpp affects similarly the width and length of the resulting wing. We also present evidence supporting the proposal that graded activity of Dpp is not an absolute requirement for wing growth.
An exploratory study of apex fence flaps on a 74 deg delta wing
NASA Technical Reports Server (NTRS)
Wahls, R. A.; Vess, R. J.
1985-01-01
An exploratory wind tunnel investigation was performed to observe the flow field effects produced by vertically deployed apex fences on a planar 74 degree delta wing. The delta shaped fences, each comprising approximately 3.375 percent of the wing area, were affixed along the first 25 percent of the wing leading edge in symmetric as well as asymmetric (i.e., fence on one side only) arrangements. The vortex flow field was visualized at angles of attack from 0 to 20 degrees using helium bubble and oil flow techniques; upper surface pressures were also measured along spanwise rows. The results were used to construct a preliminary description of the vortex patterns and induced pressures associated with vertical apex fence deployment. The objective was to obtain an initial evaluation of the potential of apex fences as vortex devices for subsonic lift modulation as well as lateral directional control of delta wing aircraft.
A major gene controls mimicry and crypsis in butterflies and moths
Nadeau, Nicola J.; Pardo-Diaz, Carolina; Whibley, Annabel; Supple, Megan; Saenko, Suzanne V.; Wallbank, Richard W. R.; Wu, Grace C.; Maroja, Luana; Ferguson, Laura; Hanly, Joseph J.; Hines, Heather; Salazar, Camilo; Merrill, Richard; Dowling, Andrea; ffrench-Constant, Richard; Llaurens, Violaine; Joron, Mathieu; McMillan, W. Owen; Jiggins, Chris D.
2016-01-01
The wing patterns of butterflies and moths (Lepidoptera) are diverse and striking examples of evolutionary diversification by natural selection1,2. Lepidopteran wing colour patterns are a key innovation, consisting of arrays of coloured scales. We still lack a general understanding of how these patterns are controlled and if there is any commonality across the 160,000 moth and 17,000 butterfly species. Here, we identify a gene, cortex, through fine-scale mapping using population genomics and gene expression analyses, which regulates pattern switches in multiple species across the mimetic radiation in Heliconius butterflies. cortex belongs to a fast evolving subfamily of the otherwise highly conserved fizzy family of cell cycle regulators3, suggesting that it most likely regulates pigmentation patterning through regulation of scale cell development. In parallel with findings in the peppered moth (Biston betularia)4, our results suggest that this mechanism is common within Lepidoptera and that cortex has become a major target for natural selection acting on colour and pattern variation in this group of insects. PMID:27251285
The gene cortex controls mimicry and crypsis in butterflies and moths.
Nadeau, Nicola J; Pardo-Diaz, Carolina; Whibley, Annabel; Supple, Megan A; Saenko, Suzanne V; Wallbank, Richard W R; Wu, Grace C; Maroja, Luana; Ferguson, Laura; Hanly, Joseph J; Hines, Heather; Salazar, Camilo; Merrill, Richard M; Dowling, Andrea J; ffrench-Constant, Richard H; Llaurens, Violaine; Joron, Mathieu; McMillan, W Owen; Jiggins, Chris D
2016-06-02
The wing patterns of butterflies and moths (Lepidoptera) are diverse and striking examples of evolutionary diversification by natural selection. Lepidopteran wing colour patterns are a key innovation, consisting of arrays of coloured scales. We still lack a general understanding of how these patterns are controlled and whether this control shows any commonality across the 160,000 moth and 17,000 butterfly species. Here, we use fine-scale mapping with population genomics and gene expression analyses to identify a gene, cortex, that regulates pattern switches in multiple species across the mimetic radiation in Heliconius butterflies. cortex belongs to a fast-evolving subfamily of the otherwise highly conserved fizzy family of cell-cycle regulators, suggesting that it probably regulates pigmentation patterning by regulating scale cell development. In parallel with findings in the peppered moth (Biston betularia), our results suggest that this mechanism is common within Lepidoptera and that cortex has become a major target for natural selection acting on colour and pattern variation in this group of insects.
Geolocators on Golden-winged Warblers do not affect migratory ecology
Peterson, Sean M.; Streby, Henry M.; Kramer, Gunnar R.; Lehman, Justin A.; Buehler, David A.; Andersen, David E.
2015-01-01
The use of light-level geolocators is increasingly common for connecting breeding and nonbreeding sites and identifying migration routes in birds. Until recently, the mass and size of geolocators precluded their use on songbird species weighing <12 g. Reducing the mass of geolocators, such as by shortening or eliminating the light stalk, may make their deployment on small birds feasible, but may also inhibit their ability to receive light reliably, because small geolocators can be shaded by feathers. Here we report geolocator effects on migratory ecology of Golden-winged Warblers (Vermivora chrysoptera) in Minnesota and Tennessee. We also evaluated whether stalk length influenced precision of location data for birds on the breeding grounds. At 8–10 g, Golden-winged Warblers are the smallest birds to be outfitted with geolocators to date. We found no differences in return rates, inter-annual territory fidelity, or body mass between geolocator-marked individuals and a control group of color-banded individuals. We observed no difference in return rates or variation in estimated breeding locations between birds marked with stalked geolocators and those with stalkless geolocators. Our results suggest that some small songbirds can be safely marked with geolocators. Light stalks appear to be unnecessary for Golden-winged Warblers; the added mass and drag of stalks can probably be eliminated on other small songbirds.
Neural basis of singing in crickets: central pattern generation in abdominal ganglia
NASA Astrophysics Data System (ADS)
Schöneich, Stefan; Hedwig, Berthold
2011-12-01
The neural mechanisms underlying cricket singing behavior have been the focus of several studies, but the central pattern generator (CPG) for singing has not been localized conclusively. To test if the abdominal ganglia contribute to the singing motor pattern and to analyze if parts of the singing CPG are located in these ganglia, we systematically truncated the abdominal nerve cord of fictively singing crickets while recording the singing motor pattern from a front-wing nerve. Severing the connectives anywhere between terminal ganglion and abdominal ganglion A3 did not preclude singing, although the motor pattern became more variable and failure-prone as more ganglia were disconnected. Singing terminated immediately and permanently after transecting the connectives between the metathoracic ganglion complex and the first unfused abdominal ganglion A3. The contribution of abdominal ganglia for singing pattern generation was confirmed by intracellular interneuron recordings and current injections. During fictive singing, an ascending interneuron with its soma and dendrite in A3 depolarized rhythmically. It spiked 10 ms before the wing-opener activity and hyperpolarized in phase with the wing-closer activity. Depolarizing current injection elicited rhythmic membrane potential oscillations and spike bursts that elicited additional syllables and reliably reset the ongoing chirp rhythm. Our results disclose that the abdominal ganglion A3 is directly involved in generating the singing motor pattern, whereas the more posterior ganglia seem to provide only stabilizing feedback to the CPG circuit. Localizing the singing CPG in the anterior abdominal neuromeres now allows analyzing its circuitry at the level of identified interneurons in subsequent studies.
Colorimetric qualification of shear sensitive liquid crystal coatings
NASA Technical Reports Server (NTRS)
Muratore, Joseph J., Jr.
1993-01-01
The work that has been done to date on the Shear Sensitive Liquid Crystal Project demonstrated that cholesteric liquid crystal coatings respond to both the direction and magnitude of a shearing force. The response of the coating is to selectively scatter incident white light into a spectrum of colors. Discernible color changes at a fixed angle of observation and illumination are the result of an applied shear stress. The intention was to be able to convert these observable color patterns from a flow visualization technique into a quantitative tool. One of the earlier intentions was to be able to use liquid crystals in dynamic flow fields. This was assumed possible because liquid crystals had made it possible to visualize transients in surface shear forces. Although the transients were visualized by color changes to an order one micro second, the time response of a coating to align to a shearing force is dependent on the magnitude of the change between its initial and final states. Unfortunately, the response is not instantaneous. It is for this reason any future attempt at quantifying the magnitude and directions of a shearing force are limited to surface shear stress vector fields in three dimensional steady state flows. This limitation does not significantly detract from the utility of liquid crystal coatings. The measurement of skin friction in the study of transition on wings, prediction of drag forces, performance assessment, and the investigation of boundary layer behavior is of great importance in aerodynamics. There exist numerous examples of techniques for the measurement of surface shear stress. Most techniques require arduous calibrations and necessitate extensive preparation of the receiving surfaces. However, the main draw back of instruments such as Preston tubes, hot films, buried wire gages, and floating element balances is that they only provide a point measurement. The advantages of capturing global shear data would be appreciable when compared with conventional point measurement sensors. It has yet to be determined if a repeatable correlation exists between the measured color of a liquid crystal coating and the magnitude/directional components of a shear vector imposed onto it.
Water color and circulation southern Chesapeake Bay, part 1
NASA Technical Reports Server (NTRS)
Nichols, M. M.; Gordon, H. H.
1975-01-01
Satellite imagery from two EREP passes over the Rappahannock Estuary of the Chesapeake region is analyzed to chart colored water types, to delineate color boundaries and define circulatory patterns. Surface observations from boats and helicopters concurrent with Skylab overpass define the distributions of suspended sediment, transparency, temperature, salinity, phytoplankton, color of suspended material and optical ratio. Important features recorded by the imagery are a large-scale turbidity maximum and massive red tide blooms. Water movement is revealed by small-scale mixing patterns and tidal plumes of apparent sediment-laden water. The color patterns broadly reflect the bottom topography and the seaward gradient of suspended material between the river and the bay. Analyses of red, green and natural color photos by microdensitometry demonstrate the utility of charting water color types of potential use for managing estuarine water quality. The Skylab imagery is superior to aerial photography and surface observations for charting water color.
Dai, Meiling; Yang, Fujun; He, Xiaoyuan
2012-04-20
A simple but effective fringe projection profilometry is proposed to measure 3D shape by using one snapshot color sinusoidal fringe pattern. One color fringe pattern encoded with a sinusoidal fringe (as red component) and one uniform intensity pattern (as blue component) is projected by a digital video projector, and the deformed fringe pattern is recorded by a color CCD camera. The captured color fringe pattern is separated into its RGB components and division operation is applied to red and blue channels to reduce the variable reflection intensity. Shape information of the tested object is decoded by applying an arcsine algorithm on the normalized fringe pattern with subpixel resolution. In the case of fringe discontinuities caused by height steps, or spatially isolated surfaces, the separated blue component is binarized and used for correcting the phase demodulation. A simple and robust method is also introduced to compensate for nonlinear intensity response of the digital video projector. The experimental results demonstrate the validity of the proposed method.
Park, Young-Jae; Lee, Jin-Moo; Yoo, Seung-Yeon; Park, Young-Bae
2016-04-01
To examine whether color parameters of tongue inspection (TI) using a digital camera was reliable and valid, and to examine which color parameters serve as predictors of symptom patterns in terms of East Asian medicine (EAM). Two hundred female subjects' tongue substances were photographed by a mega-pixel digital camera. Together with the photographs, the subjects were asked to complete Yin deficiency, Phlegm pattern, and Cold-Heat pattern questionnaires. Using three sets of digital imaging software, each digital image was exposure- and white balance-corrected, and finally L* (luminance), a* (red-green balance), and b* (yellow-blue balance) values of the tongues were calculated. To examine intra- and inter-rater reliabilities and criterion validity of the color analysis method, three raters were asked to calculate color parameters for 20 digital image samples. Finally, four hierarchical regression models were formed. Color parameters showed good or excellent reliability (0.627-0.887 for intra-class correlation coefficients) and significant criterion validity (0.523-0.718 for Spearman's correlation). In the hierarchical regression models, age was a significant predictor of Yin deficiency (β = 0.192), and b* value of the tip of the tongue was a determinant predictor of Yin deficiency, Phlegm, and Heat patterns (β = - 0.212, - 0.172, and - 0.163). Luminance (L*) was predictive of Yin deficiency (β = -0.172) and Cold (β = 0.173) pattern. Our results suggest that color analysis of the tongue using the L*a*b* system is reliable and valid, and that color parameters partially serve as symptom pattern predictors in EAM practice.
The sail wing windmill and its adaptation for use in rural India
NASA Technical Reports Server (NTRS)
Sherman, M. M.
1973-01-01
An 8 meter-diameter prototype sail wing windmill is reported that uses a one meter-diameter bullock cartwheel to which three bamboo poles are latched in a triangular pattern with overlapping ends, to form the airframe for cloth sails. This device lifts 300 pounds to a height of 20 feet in one minute in a 10 mph wind.
Waliwitiya, Ranil; Belton, Peter; Nicholson, Russell A; Lowenberger, Carl A
2010-03-01
The effects were evaluated of the plant terpenoid thymol and eight other neuroactive compounds on flight muscle impulses (FMIs) and wing beat frequency (WBF) of tethered blowflies (Phaenicia sericata Meig.). The electrical activity of the dorsolongitudinal flight muscles was closely linked to the WBF of control insects. Topically applied thymol inhibited WBF within 15-30 min and reduced FMI frequency. Octopamine and chlordimeform caused a similar, early-onset bursting pattern that decreased in amplitude with time. Desmethylchlordimeform blocked wing beating within 60 min and generated a profile of continuous but lower-frequency FMIs. Fipronil suppressed wing beating and induced a pattern of continuous, variable-frequency spiking that diminished gradually over 6 h. Cypermethrin- and rotenone-treated flies had initial strong FMIs that declined with time. In flies injected with GABA, the FMIs were generally unidirectional and frequency was reduced, as was seen with thymol. Thymol readily penetrates the cuticle and interferes with flight muscle and central nervous function in the blowfly. The similarity of the action of thymol and GABA suggests that this terpenoid acts centrally in blowflies by mimicking or facilitating GABA action.
NASA Astrophysics Data System (ADS)
Zhao, Guang-yin; Li, Ying-hong; Liang, Hua; Han, Meng-hu; Hua, Wei-zhuo
2015-01-01
Wind tunnel experiments are conducted for improving the aerodynamic performance of delta wing using a leading-edge pulsed nanosecond dielectric barrier discharge (NS-DBD). The whole effects of pulsed NS-DBD on the aerodynamic performance of the delta wing are studied by balanced force measurements. Pressure measurements and particle image velocimetry (PIV) measurements are conducted to investigate the formation of leading-edge vortices affected by the pulsed NS-DBD, compared to completely stalled flow without actuation. Various pulsed actuation frequencies of the plasma actuator are examined with the freestream velocity up to 50 m/s. Stall has been delayed substantially and significant shifts in the aerodynamic forces can be achieved at the post-stall regions when the actuator works at the optimum reduced frequency of F + = 2. The upper surface pressure measurements show that the largest change of static pressure occurs at the forward part of the wing at the stall region. The time-averaged flow pattern obtained from the PIV measurement shows that flow reattachment is promoted with excitation, and a vortex flow pattern develops. The time-averaged locations of the secondary separation line and the center of the vortical region both move outboard with excitation.
NASA Technical Reports Server (NTRS)
Helms, V. T., III; Bradley, P. F.
1984-01-01
Results are presented for oil flow and phase change paint heat transfer tests conducted on a 0.006 scale model of a proposed single stage to orbit control configured vehicle. The data were taken at angles of attack up to 40 deg at a free stream Mach number of 10 for Reynolds numbers based on model length of 0.5 x 10 to the 6th power, 1.0 x 10 to the 6th power and 2.0 x 10 to the 6th power. The magnitude and distribution of heating are characterized in terms of angle of attack and Reynolds number aided by an analysis of the flow data which are used to suggest the presence of various three dimensional flow structures that produce the observed heating patterns. Of particular interest are streak heating patterns that result in high localized heat transfer rates on the wing windward surface at low to moderate angles of attack. These streaks are caused by the bow-shock/wing-shock interaction and formation of the wing-shock. Embedded vorticity was found to be associated with these interactions.
Neural representation of form-contingent color filling-in in the early visual cortex.
Hong, Sang Wook; Tong, Frank
2017-11-01
Perceptual filling-in exemplifies the constructive nature of visual processing. Color, a prominent surface property of visual objects, can appear to spread to neighboring areas that lack any color. We investigated cortical responses to a color filling-in illusion that effectively dissociates perceived color from the retinal input (van Lier, Vergeer, & Anstis, 2009). Observers adapted to a star-shaped stimulus with alternating red- and cyan-colored points to elicit a complementary afterimage. By presenting an achromatic outline that enclosed one of the two afterimage colors, perceptual filling-in of that color was induced in the unadapted central region. Visual cortical activity was monitored with fMRI, and analyzed using multivariate pattern analysis. Activity patterns in early visual areas (V1-V4) reliably distinguished between the two color-induced filled-in conditions, but only higher extrastriate visual areas showed the predicted correspondence with color perception. Activity patterns allowed for reliable generalization between filled-in colors and physical presentations of perceptually matched colors in areas V3 and V4, but not in earlier visual areas. These findings suggest that the perception of filled-in surface color likely requires more extensive processing by extrastriate visual areas, in order for the neural representation of surface color to become aligned with perceptually matched real colors.
NASA Astrophysics Data System (ADS)
Costa, B. F. O.; Lehmann, R.; Wengerowsky, D.; Blumers, M.; Sansano, A.; Rull, F.; Schmidt, H.-J.; Dencker, F.; Niebur, A.; Klingelhöfer, G.; Sindelar, R.; Renz, F.
2016-12-01
In a rediscovered Klimt-artwork " Trompetender Putto" material tests have been conducted. We report studies on different points of the painting. The spots are of different colors, mainly taken in spots of the painting not restaurated. MIMOS II Fe-57 Mössbauer spectroscopy revealed mainly haematite and nano particle oxides in red and red/brown colors. Brown colors also contain crystallized goethite. In brown/ochre colors the same pigments as in brown colors are observed, but there is less quantity of goethite and more quantity of haematite. The green colors show Fe-rich clays, like celadonite or glauconite and or lepidocrocite as main component. Raman spectroscopy revealed cinnabar in red colors of the Scarf; and massicot in brown/ochre points, i.e. in the Left Wing of the "Putto". With scanning electron microscopy, various layers of the original and of overpainting could be recognized. The investigations of sample 1 show three layers of colored materials, which were identified as zinc-white, cinnabar and galena as well as carbon compounds. In sample 2 four layers could be detected. These are identified (bottom to top) as gypsum and lead-white (layer 1), zinc-white (layer 2), lead-white and cinnabar (layer 3) and titanium-white (layer 4). The elementary composition was examined with the portable X-ray-fluorescence analysis for qualitative manner at different points.
Selectively Patterning Polymer Opal Films via Microimprint Lithography.
Ding, Tao; Zhao, Qibin; Smoukov, Stoyan K; Baumberg, Jeremy J
2014-11-01
Large-scale structural color flexible coatings have been hard to create, and patterning color on them is key to many applications, including large-area strain sensors, wall-size displays, security devices, and smart fabrics. To achieve controlled tuning, a micro-imprinting technique is applied here to pattern both the surface morphology and the structural color of the polymer opal films (POFs). These POFs are made of 3D ordered arrays of hard spherical particles embedded inside soft shells. The soft outer shells cause the POFs to deform upon imprinting with a pre-patterned stamp, driving a flow of the soft polymer and a rearrangement of the hard spheres within the films. As a result, a patterned surface morphology is generated within the POFs and the structural colors are selectively modified within different regions. These changes are dependent on the pressure, temperature, and duration of imprinting, as well as the feature sizes in the stamps. Moreover, the pattern geometry and structural colors can then be further tuned by stretching. Micropattern color generation upon imprinting depends on control of colloidal transport in a polymer matrix under shear flow and brings many potential properties including stretchability and tunability, as well as being of fundamental interest.
Ishii, Keiko; Miyamoto, Yuri; Rule, Nicholas O; Toriyama, Rie
2014-02-01
We examined how cultural values of harmony and uniqueness are represented and maintained through physical media (i.e., colorings of geometric patterns) and how individuals play an active role in selecting and maintaining such cultural values. We found that colorings produced by European American adults and children were judged as more unique, whereas colorings produced by Japanese adults and children were judged as more harmonious, reflecting cultural differences in values. Harmony undergirded Japanese participants' preferences for colorings, whereas uniqueness undergirded European American participants' preferences for colorings. These cultural differences led participants to prefer own-culture colorings over other-culture colorings. Moreover, bicultural participants' preferences acculturated according to their identification with their host culture. Furthermore, child rearers in Japan and Canada gave feedback about the children's colorings that were consistent with their culture's values. These findings suggest that simple geometric patterns can embody cultural values that are socialized and reinforced from an early age.
Willkommen, Jana; Hörnschemeyer, Thomas
2007-06-01
The ability to fly is the decisive factor for the evolutionary success of winged insects (Pterygota). Despite this, very little is known about the ground-pattern and evolution of the functionally very important wing base. Here we use the Ephemeroptera, usually regarded as the most ancient flying insects, as a model for the analysis of the flight musculature and the sclerites of the wing base. Morphology and anatomy of the pterothorax of 13 species of Ephemeroptera and five species of Plecoptera were examined and a detailed description of Habroleptoides confusa (Ephemeroptera: Leptophlebiidae) is given. A new homology of the wing base sclerites in Ephemeroptera is proposed. The wing base of Ephemeroptera possesses three axillary sclerites that are homologous to the first axillary, the second axillary and the third axillary of Neoptera. For example, the third axillary possesses the axillary-pleural muscle that mostly is considered as a characteristic feature of the Neoptera. Many of the muscles and sclerites of the flight system of the Ephemeroptera and Neoptera can be readily homologised. In fact, there are indications that a foldable wing base may be a ground plan feature of pterygote insects and that the non-foldable wing base of the Ephemeroptera is a derived state.
Insect Wing Displacement Measurement Using Digital Holography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguayo, Daniel D.; Mendoza Santoyo, Fernando; Torre I, Manuel H. de la
2008-04-15
Insects in flight have been studied with optical non destructive techniques with the purpose of using meaningful results in aerodynamics. With the availability of high resolution and large dynamic range CCD sensors the so called interferometric digital holographic technique was used to measure the surface displacement of in flight insect wings, such as butterflies. The wings were illuminated with a continuous wave Verdi laser at 532 nm, and observed with a CCD Pixelfly camera that acquire images at a rate of 11.5 frames per second at a resolution of 1392x1024 pixels and 12 Bit dynamic range. At this frame ratemore » digital holograms of the wings were captured and processed in the usual manner, namely, each individual hologram is Fourier processed in order to find the amplitude and phase corresponding to the digital hologram. The wings displacement is obtained when subtraction between two digital holograms is performed for two different wings position, a feature applied to all consecutive frames recorded. The result of subtracting is seen as a wrapped phase fringe pattern directly related to the wing displacement. The experimental data for different butterfly flying conditions and exposure times are shown as wire mesh plots in a movie of the wings displacement.« less
Aerodynamic Interaction between Delta Wing and Hemisphere-Cylinder in Supersonic Flow
NASA Astrophysics Data System (ADS)
Nishino, Atsuhiro; Ishikawa, Takahumi; Nakamura, Yoshiaki
As future space vehicles, Reusable Launch Vehicle (RLV) needs to be developed, where there are two kinds of RLV: Single Stage To Orbit (SSTO) and Two Stage To Orbit (TSTO). In the latter case, the shock/shock interaction and shock/boundary layer interaction play a key role. In the present study, we focus on the supersonic flow field with aerodynamic interaction between a delta wing and a hemisphere-cylinder, which imitate a TSTO, where the clearance, h, between the delta wing and hemisphere-cylinder is a key parameter. As a result, complicated flow patterns were made clear, including separation bubbles.
Propeller swirl effect on single-engine general-aviation aircraft stall-spin tendencies
NASA Technical Reports Server (NTRS)
Katz, Joseph; Feistel, Terry W.
1987-01-01
An investigation is conducted of the effect of a single engine, untapered low wing general aviation aircraft propeller's swirl on the craft's stall pattern. The asymmetrical character of the propeller's swirl can trigger an early stall of one of the wings, aggravating the spin-entry condition. It is shown that the combination of this propeller-induced effect with adverse sideslip can result in large and abrupt changes in the rolling moment, in such conditions as uncoordinated low speed turning maneuvers where the pilot yaws the aircraft with wings level, rather than rolling it.
Genome of Drosophila suzukii, the Spotted Wing Drosophila
Chiu, Joanna C.; Jiang, Xuanting; Zhao, Li; Hamm, Christopher A.; Cridland, Julie M.; Saelao, Perot; Hamby, Kelly A.; Lee, Ernest K.; Kwok, Rosanna S.; Zhang, Guojie; Zalom, Frank G.; Walton, Vaughn M.; Begun, David J.
2013-01-01
Drosophila suzukii Matsumura (spotted wing drosophila) has recently become a serious pest of a wide variety of fruit crops in the United States as well as in Europe, leading to substantial yearly crop losses. To enable basic and applied research of this important pest, we sequenced the D. suzukii genome to obtain a high-quality reference sequence. Here, we discuss the basic properties of the genome and transcriptome and describe patterns of genome evolution in D. suzukii and its close relatives. Our analyses and genome annotations are presented in a web portal, SpottedWingFlyBase, to facilitate public access. PMID:24142924
In-Flight Wing Pressure Distributions for the NASA F/A-18A High Alpha Research Vehicle
NASA Technical Reports Server (NTRS)
Davis, Mark C.; Saltzman, John A.
2000-01-01
Pressure distributions on the wings of the F/A-18A High Alpha Research Vehicle (HARV) were obtained using both flush-mounted pressure orifices and surface-mounted pressure tubing. During quasi-stabilized 1-g flight, data were gathered at ranges for angle of attack from 5 deg to 70 deg, for angle of sideslip from -12 deg to +12 deg, and for Mach from 0.23 to 0.64, at various engine settings, and with and without the leading edge extension fence installed. Angle of attack strongly influenced the wing pressure distribution, as demonstrated by a distinct flow separation pattern that occurred between the range from 15 deg to 30 deg. Influence by the leading edge extension fence was evident on the inboard wing pressure distribution, but little influence was seen on the outboard portion of the wing. Angle-of-sideslip influence on wing pressure distribution was strongest at low angle of attack. Influence of Mach number was observed in the regions of local supersonic flow, diminishing as angle of attack was increased. Engine throttle setting had little influence on the wing pressure distribution.
Evolution of female-specific wingless forms in bagworm moths.
Niitsu, Shuhei; Sugawara, Hirotaka; Hayashi, Fumio
2017-01-01
The evolution of winglessness in insects has been typically interpreted as a consequence of developmental and other adaptations to various environments that are secondarily derived from a winged morph. Several species of bagworm moths (Insecta: Lepidoptera, Psychidae) exhibit a case-dwelling larval life style along with one of the most extreme cases of sexual dimorphism: wingless female adults. While the developmental process that led to these wingless females is well known, the origins and evolutionary transitions are not yet understood. To examine the evolutionary patterns of wing reduction in bagworm females, we reconstruct the molecular phylogeny of over 30 Asian species based on both mitochondrial (cytochrome c oxidase subunit I) and nuclear (28S rRNA) DNA sequences. Under a parsimonious assumption, the molecular phylogeny implies that: (i) the evolutionary wing reduction towards wingless females consisted of two steps: (Step I) from functional wings to vestigial wings (nonfunctional) and (Step II) from vestigial wings to the most specialized vermiform adults (lacking wings and legs); and (ii) vermiform morphs evolved independently at least twice. Based on the results of our study, we suggest that the evolutionary changes in the developmental system are essential for the establishment of different wingless forms in insects. © 2016 Wiley Periodicals, Inc.
Linz, David M; Tomoyasu, Yoshinori
2015-01-01
The amazing array of diversity among insect wings offers a powerful opportunity to study the mechanisms guiding morphological evolution. Studies in Drosophila (the fruit fly) have identified dozens of genes important for wing development. These genes are often called candidate genes, serving as an ideal starting point to study wing development in other insects. However, we also need to explore beyond the candidate genes to gain a more comprehensive view of insect wing evolution. As a first step away from the traditional candidate genes, we utilized Tribolium (the red flour beetle) as a model and assessed the potential involvement of a group of developmental toolkit genes (embryonic patterning genes) in beetle wing development. We hypothesized that the highly pleiotropic nature of these developmental genes would increase the likelihood of finding novel wing genes in Tribolium. Through the RNA interference screening, we found that Tc-cactus has a less characterized (but potentially evolutionarily conserved) role in wing development. We also found that the odd-skipped family genes are essential for the formation of the thoracic pleural plates, including the recently discovered wing serial homologs in Tribolium. In addition, we obtained several novel insights into the function of these developmental genes, such as the involvement of mille-pattes and Tc-odd-paired in metamorphosis. Despite these findings, no gene we examined was found to have novel wing-related roles unique in Tribolium. These results suggest a relatively conserved nature of developmental toolkit genes and highlight the limited degree to which these genes are co-opted during insect wing evolution.
Fiedler, Wolfgang
2005-06-01
An analysis of the external flight apparatus of 700 blackcaps from eight different populations (sedentary to long-distance migrators) is presented. With increasing migration distances of populations, (1) wing length, aspect ratio, and wing pointedness increase; (2) wing load decreases; (3) slots on the wing tips become relatively shorter; (4) the alula tends to be shorter in relation to wing length; and (5) the tail is shorter in relation to wing length. Although body mass increases from southern to northern populations, changes in wing length and wing area are two to three times larger than expected for simple isometric relationships. Regarding the aerodynamic background of these changes, it can be stated that traits for energy-effective flight are more strongly developed and traits for maneuverability are less developed in birds traveling longer distances, presumably as a consequence of trade-offs. Nonmigratory blackcaps from Madeira and the Cape Verde islands do not always show the traits we would expect in view of their sedentary behavior. This can be seen as a result of recent colonization of these islands by migrants or of selection by factors other than migration behavior. In migratory populations, changes between the first and the second set of primaries during first complete molt show almost the same pattern as the changes from nonmigratory to migratory populations. During molt of the primaries, blackcaps of nonmigratory populations do not show these changes. Hybrids between migrating and nonmigrating blackcap populations (Moscow and Madeira) showed intermediate values between parent populations in wing length, wing shape, and wing area; in the other variables they resembled either parent population.
Hummingbirds generate bilateral vortex loops during hovering: evidence from flow visualization
NASA Astrophysics Data System (ADS)
Pournazeri, Sam; Segre, Paolo S.; Princevac, Marko; Altshuler, Douglas L.
2012-12-01
Visualization of the vortex wake of a flying animal provides understanding of how wingbeat kinematics are translated into the aerodynamic forces for powering and controlling flight. Two general vortex flow patterns have been proposed for the wake of hovering hummingbirds: (1) The two wings form a single, merged vortex ring during each wing stroke; and (2) the two wings form bilateral vortex loops during each wing stroke. The second pattern was proposed after a study with particle image velocimetry that demonstrated bilateral source flows in a horizontal measurement plane underneath hovering Anna's hummingbirds ( Calypte anna). Proof of this hypothesis requires a clear perspective of bilateral pairs of vortices. Here, we used high-speed image sequences (500 frames per second) of C. anna hover feeding within a white plume to visualize the vortex wake from multiple perspectives. The films revealed two key structural features: (1) Two distinct jets of downwards airflow are present under each wing; and (2) vortex loops around each jet are shed during each upstroke and downstroke. To aid in the interpretation of the flow visualization data, we analyzed high-speed kinematic data (1,000 frames per second) of wing tips and wing roots as C. anna hovered in normal air. These data were used to refine several simplified models of vortex topology. The observed flow patterns can be explained by either a single loop model with an hourglass shape or a bilateral model, with the latter being more likely. When hovering in normal air, hummingbirds used an average stroke amplitude of 153.6° (range 148.9°-164.4°) and a wingbeat frequency of 38.5 Hz (range 38.1-39.1 Hz). When hovering in the white plume, hummingbirds used shallower stroke amplitudes ( bar{x} = 129.8°, range 116.3°-154.1°) and faster wingbeat frequencies ( bar{x} = 41.1 Hz, range 38.5-44.7 Hz), although the bilateral jets and associated vortices were observed across the full kinematic range. The plume did not significantly alter the air density or constrain the sustained muscle contractile frequency. Instead, higher wingbeat frequencies likely incurred a higher metabolic cost with the possible benefit of allowing the birds to more rapidly escape from the visually disruptive plume.
Hummingbirds generate bilateral vortex loops during hovering: evidence from flow visualization
NASA Astrophysics Data System (ADS)
Pournazeri, Sam; Segre, Paolo S.; Princevac, Marko; Altshuler, Douglas L.
2013-01-01
Visualization of the vortex wake of a flying animal provides understanding of how wingbeat kinematics are translated into the aerodynamic forces for powering and controlling flight. Two general vortex flow patterns have been proposed for the wake of hovering hummingbirds: (1) The two wings form a single, merged vortex ring during each wing stroke; and (2) the two wings form bilateral vortex loops during each wing stroke. The second pattern was proposed after a study with particle image velocimetry that demonstrated bilateral source flows in a horizontal measurement plane underneath hovering Anna's hummingbirds ( Calypte anna). Proof of this hypothesis requires a clear perspective of bilateral pairs of vortices. Here, we used high-speed image sequences (500 frames per second) of C. anna hover feeding within a white plume to visualize the vortex wake from multiple perspectives. The films revealed two key structural features: (1) Two distinct jets of downwards airflow are present under each wing; and (2) vortex loops around each jet are shed during each upstroke and downstroke. To aid in the interpretation of the flow visualization data, we analyzed high-speed kinematic data (1,000 frames per second) of wing tips and wing roots as C. anna hovered in normal air. These data were used to refine several simplified models of vortex topology. The observed flow patterns can be explained by either a single loop model with an hourglass shape or a bilateral model, with the latter being more likely. When hovering in normal air, hummingbirds used an average stroke amplitude of 153.6° (range 148.9°-164.4°) and a wingbeat frequency of 38.5 Hz (range 38.1-39.1 Hz). When hovering in the white plume, hummingbirds used shallower stroke amplitudes ( bar{x} = 129.8°, range 116.3°-154.1°) and faster wingbeat frequencies ( bar{x} = 41.1 Hz, range 38.5-44.7 Hz), although the bilateral jets and associated vortices were observed across the full kinematic range. The plume did not significantly alter the air density or constrain the sustained muscle contractile frequency. Instead, higher wingbeat frequencies likely incurred a higher metabolic cost with the possible benefit of allowing the birds to more rapidly escape from the visually disruptive plume.
Reversible thermochromic response based on photonic crystal structure in butterfly wing
NASA Astrophysics Data System (ADS)
Wang, Wanlin; Wang, Guo Ping; Zhang, Wang; Zhang, Di
2018-01-01
Subtle responsive properties can be achieved by the photonic crystal (PC) nanostructures of butterfly based on thermal expansion effect. The studies focused on making the sample visually distinct. However, the response is restricted by limited thermal expansion coefficients. We herein report a new class of reversible thermochromic response achieved by controlling the ambient refractive index in butterfly PC structure. The photonic ethanol-filled nanoarchitecture sample is simply assembled by sealing liquid ethanol filling Papilio ulysses butterfly wing. Volatile ethanol is used to modulate the ambient refractive index. The sample is sealed with glasses to ensure reversibility. Liquid ethanol filling butterfly wing demonstrated significant allochroic response to ambient refractive index, which can be controlled by the liquefaction and vaporization of ethanol. This design is capable of converting thermal energy into visual color signals. The mechanism of this distinct response is simulated and proven by band theory. The response properties are performed with different filled chemicals and different structure parameters. Thus, the reversible thermochromic response design might have potential use in the fields such as detection, photonic switch, displays, and so forth.
Blind color isolation for color-channel-based fringe pattern profilometry using digital projection
NASA Astrophysics Data System (ADS)
Hu, Yingsong; Xi, Jiangtao; Chicharo, Joe; Yang, Zongkai
2007-08-01
We present an algorithm for estimating the color demixing matrix based on the color fringe patterns captured from the reference plane or the surface of the object. The advantage of this algorithm is that it is a blind approach to calculating the demixing matrix in the sense that no extra images are required for color calibration before performing profile measurement. Simulation and experimental results convince us that the proposed algorithm can significantly reduce the influence of the color cross talk and at the same time improve the measurement accuracy of the color-channel-based phase-shifting profilometry.
Cavicchi, Sandro; Guerra, Daniela; Giorgi, Gianfranco; Pezzoli, Cristina
1985-01-01
The effects of environmental temperature on wing size and shape of Drosophila melanogaster were analyzed in populations derived from an Oregon laboratory strain kept at three temperatures (18°, 25°, 28°) for 4 yr. Temperature-directed selection was identified for both wing size and shape. The length of the four longitudinal veins, used as a test for wing size variations in the different populations, appears to be affected by both genetic and maternal influences. Vein expression appears to be dependent upon developmental pattern of the wing: veins belonging to the same compartment are coordinated in their expression and relative position, whereas veins belonging to different compartments are not. Both wing and cell areas show genetic divergence, particularly in the posterior compartment. Cell number seems to compensate for cell size variations. Such compensation is carried out both at the level of single organisms and at the level of population as a whole. The two compartments behave as individual units of selection. PMID:17246257
Replication of cicada wing's nano-patterns by hot embossing and UV nanoimprinting
NASA Astrophysics Data System (ADS)
Hong, Sung-Hoon; Hwang, Jaeyeon; Lee, Heon
2009-09-01
The hydrophobicity of the cicada wing originates from its naturally occurring, surface nano-structure. The nano-structure of the cicada wing consists of an array of nano-sized pillars, 100 nm in diameter and 300 nm in height. In this study, the nano-structure of the cicada wing was successfully duplicated by using hot embossing lithography and UV nanoimprint lithography (NIL). The diameter and pitch of replication were the same as those of the original cicada wing and the height was a little smaller than that of the original master. The transmittance of the hot embossed PVC film was increased by 2-6% compared with that of the bare PVC film. The hydrophobicity was measured by water contact angle measurements. The water contact angle of the replica, made of UV cured polymer, was 132° ± 2°, which was slightly lower than that of the original cicada wing (138° ± 2°), but much higher than that of the UV cured polymer surface without any nano-sized pillars (86°).
Rosetti, Natalia; Remis, Maria I
2018-06-06
Wing dimorphism occurs widely in insects and involves discontinuous variation in a wide variety of traits involved in fight and reproduction. In the current study, we analyzed the spatial pattern of wing dimorphism and intraspecific morphometric variation in nine natural populations of the grasshopper Dichroplus vittatus (Bruner; Orthoptera: Acrididae) in Argentina. Considerable body size differences among populations, between sexes and wing morphs were detected. As a general trend, females were larger than males and macropterous individuals showed increased thorax length over brachypterous which can be explained by the morphological requirements for the development of flight muscles in the thoracic cavity favoring dispersal. Moreover, when comparing wing morphs, a higher phenotypic variability was detected in macropterous females. The frequency of macropterous individuals showed negative correlation with longitude and positive with precipitations, indicating that the macropterous morph is more frequent in the humid eastern part of the studied area. Our results provide valuable about spatial variation of fully winged morph and revealed geographic areas in which the species would experience greater dispersal capacity.
Color camera computed tomography imaging spectrometer for improved spatial-spectral image accuracy
NASA Technical Reports Server (NTRS)
Wilson, Daniel W. (Inventor); Bearman, Gregory H. (Inventor); Johnson, William R. (Inventor)
2011-01-01
Computed tomography imaging spectrometers ("CTIS"s) having color focal plane array detectors are provided. The color FPA detector may comprise a digital color camera including a digital image sensor, such as a Foveon X3.RTM. digital image sensor or a Bayer color filter mosaic. In another embodiment, the CTIS includes a pattern imposed either directly on the object scene being imaged or at the field stop aperture. The use of a color FPA detector and the pattern improves the accuracy of the captured spatial and spectral information.
Kaulfuss, Uwe; Moulds, Max
2015-01-01
Abstract A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarcta zealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns. PMID:25829843
Kaulfuss, Uwe; Moulds, Max
2015-01-01
A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarctazealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns.
The timing of wing molt in tundra swans: energetic and non-energetic constraints
Earnst, S.L.
1992-01-01
Date of wing molt initiation, based on the regression of tenth primary length on capture date, was calculated for breeding and nonbreeding Tundra Swans (Cygnus columbianus columbianus) on the Colville River Delta, Alaska. Breeding females initiated wing molt significantly later than breeding males and nonbreeding males and females; the molt of breeding females was correlated with the date on which their eggs hatched. Breeding males did not differ significantly from nonbreeding males and females in the date of molt initiation. Timing of molt in breeding males and females was consistent with the views that females delay molt while replenishing energy spent on reproduction, but was also consistent with the breeding pair's need for primaries to defend territories and to defend and brood young. Other results, including an increase in an index of female body condition throughout most of the molt period, and a positive correlation between clutch size and female hatch-to-molt interval, were not predicted by the hypothesis that past energy expenditures constrain the timing of molt. Patterns of wing molt within and among other Northern Hemisphere geese and swans are also difficult to explain on the basis of energetics alone. For example, breeding females initiate molt before breeding males in many species. Also, there is extreme asynchrony between mates in two swan species; one of those species also exhibits variation in which sex initiates wing molt first. Both patterns suggest that asynchrony, per se, is important, probably to facilitate brood protection or territory defense. In Tundra Swans and other northern breeding geese and swans, the non-energetic demands of territory defense, brood defense, and brooding are probably important constraints on the timing of wing molt.
Voice response system of color and pattern on clothes for visually handicapped person.
Miyake, Masao; Manabe, Yoshitsugu; Uranishi, Yuki; Imura, Masataka; Oshiro, Osamu
2013-01-01
For visually handicapped people, a mental support is important in their independent daily life and participation in a society. It is expected to develop a system which can recognize colors and patterns on clothes so that they can go out with less concerns. We have worked on a basic study into such a system, and developed a prototype system which can stably recognize colors and patterns and immediately provide these information in voice, when a user faces it to clothes. In the results of evaluation experiments it is shown that the prototype system is superior to the system in the basic study at the accuracy rate for the recognition of color and pattern.
Mikó, István; Copeland, Robert S.; Balhoff, James P.; Yoder, Matthew J.; Deans, Andrew R.
2014-01-01
We revise two relatively rare ensign wasp genera, whose species are restricted to Sub-Saharan Africa: Afrevania and Trissevania. Afrevania longipetiolata sp. nov., Trissevania heatherae sp. nov., T. hugoi sp. nov., T. mrimaensis sp. nov. and T. slideri sp. nov. are described, males and females of T. anemotis and Afrevania leroyi are redescribed, and an identification key for Trissevaniini is provided. We argue that Trissevania mrimaensis sp. nov. and T. heatherae sp. nov. populations are vulnerable, given their limited distributions and threats from mining activities in Kenya. We hypothesize that these taxa together comprise a monophyletic lineage, Trissevaniini, tr. nov., the members of which share the ability to fold their fore wings along two intersecting fold lines. Although wing folding of this type has been described for the hind wing of some insects four-plane wing folding of the fore wing has never been documented. The wing folding mechanism and the pattern of wing folds of Trissevaniini is shared only with some cockroach species (Blattodea). It is an interesting coincidence that all evaniids are predators of cockroach eggs. The major wing fold lines of Trissevaniini likely are not homologous to any known longitudinal anatomical structures on the wings of other Evaniidae. Members of the new tribe share the presence of a coupling mechanism between the fore wing and the mesosoma that is composed of a setal patch on the mesosoma and the retinaculum of the fore wing. While the setal patch is an evolutionary novelty, the retinaculum, which originally evolved to facilitate fore and hind wing coupling in Hymenoptera, exemplifies morphological exaptation. We also refine and clarify the Semantic Phenotype approach used in previous taxonomic revisions and explore the consequences of merging new with existing data. The way that semantic statements are formulated can evolve in parallel, alongside improvements to the ontologies themselves. PMID:24787704
Rajabi, H.; Ghoroubi, N.; Malaki, M.; Darvizeh, A.; Gorb, S. N.
2016-01-01
Dragonflies and damselflies, belonging to the order Odonata, are known to be excellent fliers with versatile flight capabilities. The ability to fly over a wide range of speeds, high manoeuvrability and great agility are a few characteristics of their flight. The architecture of the wings and their structural elements have been found to play a major role in this regard. However, the precise influence of individual wing components on the flight performance of these insects remains unknown. The design of the wing basis (so called basal complex) and the venation of this part are responsible for particular deformability and specific shape of the wing blade. However, the wing bases are rather different in representatives of different odonate groups. This presumably reflects the dimensions of the wings on one hand, and different flight characteristics on the other hand. In this article, we develop the first three-dimensional (3D) finite element (FE) models of the proximal part of the wings of typical representatives of five dragonflies and damselflies families. Using a combination of the basic material properties of insect cuticle, a linear elastic material model and a nonlinear geometric analysis, we simulate the mechanical behaviour of the wing bases. The results reveal that although both the basal venation and the basal complex influence the structural stiffness of the wings, it is only the latter which significantly affects their deformation patterns. The use of numerical simulations enabled us to address the role of various wing components such as the arculus, discoidal cell and triangle on the camber formation in flight. Our study further provides a detailed representation of the stress concentration in the models. The numerical analysis presented in this study is not only of importance for understanding structure-function relationship of insect wings, but also might help to improve the design of the wings for biomimetic micro-air vehicles (MAVs). PMID:27513753
Bai, Ling; Mai, Van Cuong; Lim, Yun; Hou, Shuai; Möhwald, Helmuth; Duan, Hongwei
2018-03-01
Structural colors originating from interaction of light with intricately arranged micro-/nanostructures have stimulated considerable interest because of their inherent photostability and energy efficiency. In particular, noniridescent structural color with wide viewing angle has been receiving increasing attention recently. However, no method is yet available for rapid and large-scale fabrication of full-spectrum structural color patterns with wide viewing angles. Here, infiltration-driven nonequilibrium assembly of colloidal particles on liquid-permeable and particle-excluding substrates is demonstrated to direct the particles to form amorphous colloidal arrays (ACAs) within milliseconds. The infiltration-assisted (IFAST) colloidal assembly opens new possibilities for rapid manufacture of noniridescent structural colors of ACAs and straightforward structural color mixing. Full-spectrum noniridescent structural colors are successfully produced by mixing primary structural colors of red, blue, and yellow using a commercial office inkjet printer. Rapid fabrication of large-scale structural color patterns with sophisticated color combination/layout by IFAST printing is realized. The IFAST technology is versatile for developing structural color patterns with wide viewing angles, as colloidal particles, inks, and substrates are flexibly designable for diverse applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Yang, Qingqing; Zhu, Shenmin; Peng, Wenhong; Yin, Chao; Wang, Wanlin; Gu, Jiajun; Zhang, Wang; Ma, Jun; Deng, Tao; Feng, Chuanliang; Zhang, Di
2013-06-25
We herein report a new class of photonic crystals with hierarchical structures, which are of color tunability over pH. The materials were fabricated through the deposition of polymethylacrylic acid (PMAA) onto a Morpho butterfly wing template by using a surface bonding and polymerization route. The amine groups of chitosan in Morpho butterfly wings provide reaction sites for the MAA monomer, resulting in hydrogen bonding between the template and MAA. Subsequent polymerization results in PMAA layers coating homogenously on the hierarchical photonic structures of the biotemplate. The pH-induced color change was detected by reflectance spectra as well as optical observation. A distinct U transition with pH was observed, demonstrating PMAA content-dependent properties. The appearance of the unique U transition results from electrostatic interaction between the -NH3(+) of chitosan and the -COO(-) groups of PMAA formed, leading to a special blue-shifted point at the pH value of the U transition, and the ionization of the two functional groups in the alkali and acid environment separately, resulting in a red shift. This work sets up a strategy for the design and fabrication of tunable photonic crystals with hierarchical structures, which provides a route for combining functional polymers with biotemplates for wide potential use in many fields.
On the uniqueness of color patterns in raptor feathers
Ellis, D.H.
2009-01-01
For this study, I compared sequentially molted feathers for a few captive raptors from year to year and symmetrically matched feathers (left/right pairs) for many raptors to see if color patterns of sequential feather pairs were identical or if symmetrical pairs were mirror-image identical. Feather pairs were found to be identical only when without color pattern (e.g., the all-white rectrices of Bald Eagles [Haliaeetus leucocephalus]). Complex patterns were not closely matched, but some simple patterns were sometimes closely matched, although not identical. Previous claims that complex color patterns in feather pairs are fingerprint-identical (and therefore that molted feathers from wild raptors can be used to identify breeding adults from year to year with certainty) were found to be untrue: each feather is unique. Although it is unwise to be certain of bird of origin using normal feathers, abnormal feathers can often be so used. ?? 2009 The Raptor Research Foundation, Inc.
NASA Astrophysics Data System (ADS)
Rajyaguru, Parth K.; Pegram, Kimberly V.; Kingston, Alexandra C. N.; Rutowski, Ronald L.
2013-06-01
In many animals, males bear bright ornamental color patches that may signal both the direct and indirect benefits that a female might accrue from mating with him. Here we test whether male coloration in the Pipevine Swallowtail butterfly, Battus philenor, predicts two potential direct benefits for females: brief copulation duration and the quantity of materials the male passes to the female during mating. In this species, males have a bright iridescent blue field on the dorsal hindwing surface, while females have little or no dorsal iridescence. Females preferentially mate with males who display a bright and highly chromatic blue field on their dorsal hindwing. In this study, we show that the chroma of the blue field on the male dorsal hindwing and male body size (forewing length) significantly predict the mass of material or spermatophore that a male forms within the female's copulatory sac during mating. We also found that spermatophore mass correlated negatively with copulation duration, but that color variables did not significantly predict this potential direct benefit. These results suggest that females may enhance the material benefits they receive during mating by mating with males based on the coloration of their dorsal hindwing.
Park, Jiyoon; Woo, Ok Hee; Shin, Hye Seon; Cho, Kyu Ran; Seo, Bo Kyoung; Kang, Eun Young
2015-10-01
The purpose of this study is to evaluate the diagnostic performance of SWE in palpable breast mass and to compare with color overlay pattern in SWE with conventional US and quantitative SWE for assessing palpable breast mass. SWE and conventional breast US were performed in 133 women with 156 palpable breast lesions (81 benign, 75 malignant) between August 2013 to June 2014. Either pathology or periodic imaging surveillance more than 2 years was a reference standard. Existence of previous image was blinded to performing radiologists. US BI-RADS final assessment, qualitative and quantitative SWE measurements were evaluated. Diagnostic performances of grayscale US, SWE and US combined to SWE were calculated and compared. Correlation between pattern classification and quantitative SWE was evaluated. Both color overlay pattern and quantitative SWE improved the specificity of conventional US, from 81.48% to 96.30% (p=0.0005), without improvement in sensitivity. Color overlay pattern was significantly related to all quantitative SWE parameters and malignancy rate (p<0.0001.). The optimal cutoff of color overlay pattern was between 2 and 3. Emax with optimal cutoff at 45.1 kPa showed the highest Az value, sensitivity, specificity and accuracy among other quantitative SWE parameters (p<0.0001). Echogenic halo on grayscale US showed significant correlation with color overlay pattern and pathology (p<0.0001). In evaluation of palpable breast mass, conventional US combine to SWE improves specificity and reduces the number of biopsies that ultimately yield a benign result. Color overlay pattern classification is more quick and easy and may represent quantitative SWE measurements with similar diagnostic performances. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
A bioinspired approach to the generation of novel antimicrobial materials
NASA Astrophysics Data System (ADS)
Nowlin, Kyle S.
Advancements in particle beam microscopy have allowed scientists to discover a wealth of surface architectures with nanoscale dimensions, many of which endow the surfaces with fascinating properties. Investigations of such surfaces have revealed some exciting physical phenomena, ranging from complex interactions with light such as brilliant iridescent colors resulting from diffraction and interference to water repelling self-cleaning superhydrophobic surfaces. Interestingly, the biological world, especially that of insects, has perhaps contributed the greatest number of these discoveries and will likely continue to do so as long as scientists entertain the idea that nature still has a vast collection of lessons to teach us. Examples of such phenomena include the structurally derived colors displayed by Chrysiridia rhipheus (Madagascan sunset moth), the anti-reflective and self-cleaning wings of Psaltoda claripennis (Clanger cicada), along with its more recent discovery of mechanically induced bactericidal activity. The implications of such a discovery are truly revolutionary as it is the first time that surface topography has been linked to microbial death. With this discovery a new defensive strategy against biofilm derived pathogenesis and related problems has arrived and must be further investigated for a more thorough understanding. It's a generally accepted notion that fungi much like bacteria can form complex protective biofilms and are undoubtedly a source of pathogenesis. For example C. albicans is the fourth most frequent organism found in the blood of hospitalized patients. While bacterial infections have been given much attention, less has been given to fungal biofilms though they are a major source of nosocomial infections attributed in part to adhesion to invasive devices such as catheters, cardiac pacemakers, prosthetic heart valves etc. S. cerevisiae, a generally non-pathogenic yeast, has been proposed as a model for fungal biofilm formation with similar behaviors but far more genetic tools available. In the present work I investigate the effects that the nano-structured wings of our local Dog Day cicada Tibicen tibicen have on adhered S. cerevisiae to assess for antifungal activity. Resembling that of the bactericidal activity, my study concludes antifungal activity of a cell rupturing mechanical nature attributed to the nano-topography of the Dog Day cicada wing. Following this discovery I utilize nano-sphere lithography (NSL) to fabricate analogous nanostructures as well as proportionally smaller and larger nanostructures in common synthetic polymers to be tested for translation of function. Studies with E. coli and S. cerevisiae reveal the overlooked but fundamentally important mechanical properties of nano-structures as they apply to mechanical microbicidal functionality. In addition to biocidal activity studies, I also demonstrate the remarkable anti-adhesive nature of a particular scale nano-patterned surface relative to flat surfaces of analogous chemistry.
The Effect of Large Angles of Yaw on the Accuracy of Wing-Tip Yawmeters
NASA Technical Reports Server (NTRS)
Golden, Jacob
1942-01-01
The present method used by the NACA for the measurement of sideslip angles in flight involves the use of a device called the yawmeter. The operation of this instrument depends on the motion of a free-swinging vane which, mounted ahead of the wing tip, alines itself with the local wind direction. Because of the flow pattern about the airplane, the local wind direction at the yaw vane may be slightly different from the direction of the relative wind and the yaw-vane readings may be in error. This error is corrected by using half the difference between the readings of two vanes, one on each wing, for unyawed flight as a calibration constant. It is possible, however, that, because of the change in location of the vane with respect to the flow pattern at large angles of yaw, the constant obtained for unyawed flight may not apply. The present report covers power-off tests made in the free-flight tunnel to check the validity of this method.
Rizzi, Samantha Karlla Lopes de Almeida; Haddad, Cinira Assad Simão; Giron, Patricia Santolia; Pinheiro, Thaís Lúcia; Nazário, Afonso Celso Pinto; Facina, Gil
2016-06-01
The aim of this study was to determine the incidence of winged scapula after breast cancer surgery, its impact on shoulder morbidity and difference in incidence according to surgery type. Patients with breast cancer and surgical indication for axillary dissection were included. A total of 112 patients were surveyed with one physical evaluation before the surgery and others 15, 30, 90, and 180 days after. Winged scapula was assessed with test proposed by Hoppenfeld. Shoulder range of motion (ROM) was assessed with goniometer for flexion, extension, adduction, abduction, internal rotation, and external rotation. A verbal scale from 0 to 10 was used to assess pain. Winged scapula incidence was 8.0 % 15 days after surgery. Two patients recovered from winged scapula 90 days after surgery and four more 180 days after surgery, while three patients still had winged scapula at this time. The incidence after 15 days from surgery was 20.9 and 22.6 % among patients submitted to sentinel node biopsy or axillary lymphadenectomy (AL), respectively (p < 0.01). There was no statistical difference of incidence according to breast surgery type. Operated side shoulder flexion, adduction, and abduction ROM changes were statistically different in patients with or without winged scapula. The mean reduction was higher in patients with winged scapula. Both groups showed the same pattern over time in pain. Winged scapula incidence was 8.0 % and was higher in AL, and prevalence decreased during 6 months after surgery. Patients who developed winged scapula had more shoulder flexion, adduction, and abduction limitation.
NASA Astrophysics Data System (ADS)
Krishnan, Krishnamoorthy; Naqavi, Iftekhar Z.; Gurka, Roi
2017-11-01
Understanding the physics of flapping wings at moderate Reynolds number flows takes on greater importance in the context of avian aerodynamics as well as in the design of miniature-aerial-vehicles. Analyzing the characteristics of wake vortices generated downstream of flapping wings can help to explain the unsteady contribution to the aerodynamics loads. In this study, numerical simulations of flow over a bio-inspired pseudo-2D flapping wing model was conducted to characterize the evolution of unsteady flow structures in the downstream wake of flapping wing. The wing model was based on a European starling's wing and wingbeat kinematics were incorporated to simulate a free-forward flight. The starling's wingbeat kinematics were extracted from experiments conducted in a wind tunnel where freely flying starling was measured using high-speed PIV as well as high-speed imaging yielding a series of kinematic images sampled at 500 Hz. The average chord of the wing section was 6 cm and simulations were carried out at a Reynolds number of 54,000, reduced frequency of 0.17, and Strouhal number of 0.16. Large eddy simulation was performed using a second order, finite difference code ParLES. Characteristics of wake vortex structures during the different phases of the wing strokes were examined. The role of wingbeat kinematics in the configuration of downstream vortex patterns is discussed. Evaluated wake topology and lift-drag characteristics are compared with the starling's wind tunnel results.
Lin, Xinda; Yao, Yun; Wang, Bo; Emlen, Douglas J; Lavine, Laura Corley
2016-01-01
Crowding and changes in food availability are two critical environmental conditions that impact an animal's trajectory toward either migration or reproduction. Many insects facing this challenge have evolved wing polyphenisms. When conditions favor reproduction, wing polyphenic species produce adults that either have no wings or short, non-functional wings. Facultative wing growth reflects a physiological and evolutionary trade-off between migration and reproduction, triggered by environmental conditions. How environmental cues are transduced to produce these alternative forms, and their associated ecological shift from migration to reproduction, remains an important unsolved problem in evolutionary ecology. The brown planthopper, a wing polymorphic insect exhibiting strong trade-offs in investment between migration and reproduction, is one of the most serious rice pests in Asia. In this study, we investigated the function of four genes in the insulin-signaling pathway known to couple nutrition with growth, PI3 Kinase (PI3K), PDK1, Akt (Protein Kinase B), and the forkhead gene FOXO. Using a combination of RNA interference and pharmacological inhibitor treatment, we show that all four genes contribute to tissue level regulation of wing polymorphic development in this insect. As predicted, silencing of the NlPI3K, NlAkt and NlPDK1 through dsRNA and with the pharmacological inhibitor Perifosine resulted in short-winged brown planthoppers, whereas knockdown of NlFOXO resulted in long-winged planthoppers. Morphometric analyses confirm that phenotypes from our manipulations mimic what would be found in nature, i.e., major parameters such as bristle number, wing area and body weight are not significantly different from non-experimental animals. Taken together, these data implicate the insulin-signaling pathway in the transduction of environmental factors into condition-dependent patterns of wing growth in insects.
Morphogenesis in bat wings: linking development, evolution and ecology.
Adams, Rick A
2008-01-01
The evolution of powered flight in mammals required specific developmental shifts from an ancestral limb morphology to one adapted for flight. Through studies of comparative morphogenesis, investigators have quantified points and rates of divergence providing important insights into how wings evolved in mammals. Herein I compare growth,development and skeletogenesis of forelimbs between bats and the more ancestral state provided by the rat (Rattus norvegicus)and quantify growth trajectories that illustrate morphological divergence both developmentally and evolutionarily. In addition, I discuss how wing shape is controlled during morphogenesis by applying multivariate analyses of wing bones and wing membranes and discuss how flight dynamics are stabilized during flight ontogeny. Further, I discuss the development of flight in bats in relation to the ontogenetic niche and how juveniles effect populational foraging patterns. In addition, I provide a hypothetical ontogenetic landscape model that predicts how and when selection is most intense during juvenile morphogenesis and test this model with data from a population of the little brown bat, Myotis lucifugus. (c) 2007 S. Karger AG, Basel
Boundary Dpp promotes growth of medial and lateral regions of the Drosophila wing
Barrio, Lara; Milán, Marco
2017-01-01
The gradient of Decapentaplegic (Dpp) in the Drosophila wing has served as a paradigm to characterize the role of morphogens in regulating patterning. However, the role of this gradient in regulating tissue size is a topic of intense debate as proliferative growth is homogenous. Here, we combined the Gal4/UAS system and a temperature-sensitive Gal80 molecule to induce RNAi-mediated depletion of dpp and characterise the spatial and temporal requirement of Dpp in promoting growth. We show that Dpp emanating from the AP compartment boundary is required throughout development to promote growth by regulating cell proliferation and tissue size. Dpp regulates growth and proliferation rates equally in central and lateral regions of the developing wing appendage and reduced levels of Dpp affects similarly the width and length of the resulting wing. We also present evidence supporting the proposal that graded activity of Dpp is not an absolute requirement for wing growth. DOI: http://dx.doi.org/10.7554/eLife.22013.001 PMID:28675372
Exploring bird aerodynamics using radio-controlled models.
Hoey, Robert G
2010-12-01
A series of radio-controlled glider models was constructed by duplicating the aerodynamic shape of soaring birds (raven, turkey vulture, seagull and pelican). Controlled tests were conducted to determine the level of longitudinal and lateral-directional static stability, and to identify the characteristics that allowed flight without a vertical tail. The use of tail-tilt for controlling small bank-angle changes, as observed in soaring birds, was verified. Subsequent tests, using wing-tip ailerons, inferred that birds use a three-dimensional flow pattern around the wing tip (wing tip vortices) to control adverse yaw and to create a small amount of forward thrust in gliding flight.
Wilts, Bodo D.; Michielsen, Kristel; De Raedt, Hans; Stavenga, Doekele G.
2012-01-01
The cover scales on the wing of the Emerald-patched Cattleheart butterfly, Parides sesostris, contain gyroid-type biological photonic crystals that brightly reflect green light. A pigment, which absorbs maximally at approximately 395 nm, is immersed predominantly throughout the elaborate upper lamina. This pigment acts as a long-pass filter shaping the reflectance spectrum of the underlying photonic crystals. The additional effect of the filtering is that the spatial distribution of the scale reflectance is approximately angle-independent, leading to a stable wing pattern contrast. The spectral tuning of the original reflectance is verified by photonic band structure modelling. PMID:24098853
Saito, Kazuya; Nomura, Shuhei; Yamamoto, Shuhei; Niiyama, Ryuma; Okabe, Yoji
2017-05-30
Ladybird beetles are high-mobility insects and explore broad areas by switching between walking and flying. Their excellent wing transformation systems enabling this lifestyle are expected to provide large potential for engineering applications. However, the mechanism behind the folding of their hindwings remains unclear. The reason is that ladybird beetles close the elytra ahead of wing folding, preventing the observation of detailed processes occurring under the elytra. In the present study, artificial transparent elytra were transplanted on living ladybird beetles, thereby enabling us to observe the detailed wing-folding processes. The result revealed that in addition to the abdominal movements mentioned in previous studies, the edge and ventral surface of the elytra, as well as characteristic shaped veins, play important roles in wing folding. The structures of the wing frames enabling this folding process and detailed 3D shape of the hindwing were investigated using microcomputed tomography. The results showed that the tape spring-like elastic frame plays an important role in the wing transformation mechanism. Compared with other beetles, hindwings in ladybird beetles are characterized by two seemingly incompatible properties: ( i ) the wing rigidity with relatively thick veins and ( ii ) the compactness in stored shapes with complex crease patterns. The detailed wing-folding process revealed in this study is expected to facilitate understanding of the naturally optimized system in this excellent deployable structure.
Nomura, Shuhei; Yamamoto, Shuhei; Niiyama, Ryuma; Okabe, Yoji
2017-01-01
Ladybird beetles are high-mobility insects and explore broad areas by switching between walking and flying. Their excellent wing transformation systems enabling this lifestyle are expected to provide large potential for engineering applications. However, the mechanism behind the folding of their hindwings remains unclear. The reason is that ladybird beetles close the elytra ahead of wing folding, preventing the observation of detailed processes occurring under the elytra. In the present study, artificial transparent elytra were transplanted on living ladybird beetles, thereby enabling us to observe the detailed wing-folding processes. The result revealed that in addition to the abdominal movements mentioned in previous studies, the edge and ventral surface of the elytra, as well as characteristic shaped veins, play important roles in wing folding. The structures of the wing frames enabling this folding process and detailed 3D shape of the hindwing were investigated using microcomputed tomography. The results showed that the tape spring-like elastic frame plays an important role in the wing transformation mechanism. Compared with other beetles, hindwings in ladybird beetles are characterized by two seemingly incompatible properties: (i) the wing rigidity with relatively thick veins and (ii) the compactness in stored shapes with complex crease patterns. The detailed wing-folding process revealed in this study is expected to facilitate understanding of the naturally optimized system in this excellent deployable structure. PMID:28507159
Zhou, Shuang-Shuang; Sun, Ze; Ma, Weihua; Chen, Wei; Wang, Man-Qun
2014-03-01
We sequenced the antenna transcriptome of the brown planthopper (BPH), Nilaparvata lugens (Stål), a global rice pest, and performed transcriptome analysis on BPH antenna. We obtained about 40million 90bp reads that were assembled into 75,874 unigenes with a mean size of 456bp. Among the antenna transcripts, 32,856 (43%) showed significant similarity (E-value <1e(-5)) to known proteins in the NCBI database. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to classify functions of BPH antenna genes. We identified 10 odorant-binding proteins (OBPs), including 7 previously unidentified, and 11 chemosensory proteins (CSPs), including two new members. The expression profiles of 4 OBPs and 2 CSPs were determined by q-PCR for antenna, abdomen, leg and wing of insects of different age, gender, and mating status including two BPH adult wing-morphology types. NlugCSP10 and 4 OBPs appeared to be antenna-specific because they were highly and differentially expressed in male and female antennae. NlugCSP11 was expressed ubiquitously, with particularly high expression in wings. The transcript levels of several olfactory genes depended on adult wing form, age, gender, and mating status, although no clear expression patterns were determined. Copyright © 2013 Elsevier Inc. All rights reserved.
Shape matters: improved flight in tapered auto-rotating wings
NASA Astrophysics Data System (ADS)
Liu, Yucen; Vincent, Lionel; Kanso, Eva
2017-11-01
Many plants use gravity and wind to disperse their seeds. The shape of seed pods influence their aerodynamics. For example, Liana seeds form aerodynamic gliders and Sycamore trees release airborne ``helicopters.'' Here, we use carefully-controlled experiments and high-speed photography to examine dispersion by tumbling (auto-rotation) and we focus on the effect of geometry on flight characteristics. We consider four families of shapes: rectangular, elliptic, tapered, and sharp-tip wings, and we vary the span-to-chord ratio. We find that tapered wings exhibit extended flight time and range, that is, better performance. A quasi-steady two-dimensional model is used to highlight the mechanisms by which shape affects flight performance. These findings could have significant implications on linking seedpod designs to seed dispersion patterns as well as on optimizing wing design in active flight problems.
Design and development of flapping wing micro air vehicle
NASA Astrophysics Data System (ADS)
Hynes, N. Rajesh Jesudoss; Solomon, A. Jeffey Markus; Kathiresh, E.; Brighton, D.; Velu, P. Shenbaga
2018-05-01
Birds and insects have different methods of producing lift and thrust for hovering and forward flight. Most birds, however, cannot hover. Wing tips of birds follow simple paths in flight, whereas insects have very complicated wing tip paths, for hovering and forward flight, which vary with each species. FMAV based on avian flight. Development of Flapping Wing Air Vehicle (FWAV) is an on-going quest to master the natural flyers by mechanical means. It is characterized by unsteady aerodynamics, whose knowledge is still developing. The present work aims at include being capable of manoeuvring around and over obstacles by adjusting pitch, yaw, and roll, able to glide for five seconds under its own power, skilful at alternating between flapping and gliding with minimal disruption of flight pattern and being durable enough to withstand impacts with minimal to no damage.
Waliwitiya, Ranil; Belton, Peter; Nicholson, Russell A; Lowenberger, Carl A
2012-02-01
We evaluated the acute toxicities and the physiological effects of plant monoterpenoids (eugenol, pulegone, citronellal and alpha-terpineol) and neuroactive insecticides (malathion, dieldrin and RH3421) on flight muscle impulses (FMI) and wing beat signals (WBS) of the blow fly (Phaenicia sericata). Topically-applied eugenol, pulegone, citronellal, and alpha-terpineol produced neurotoxic symptoms, but were less toxic than malathion, dieldrin, or RH3421. Topical application of eugenol, pulegone, and citronellal reduced spike amplitude in one of the two banks of blow fly dorsolongitudinal flight muscles within 6-8 min, but with citronellal, the amplitude of FMIs reverted to a normal pattern within 1 hr. In contrast to pulegone and citronellal, where impulse frequency remained relatively constant, eugenol caused a gradual increase, then a decline in the frequency of spikes in each muscle bank. Wing beating was blocked permanently within 6-7 min of administering pulegone or citronellal and within 16 mins with eugenol. alpha-Terpineol-treated blow flies could not beat their wings despite normal FMI patterns. The actions of these monoterpenoids on blow fly flight motor patterns are discussed and compared with those of dieldrin, malathion, RH3421, and a variety of other neuroactive substances we have previously investigated in this system. Eugenol, pulegone and citronellal readily penetrate blow fly cuticle and interfere with flight muscle and/or central nervous function. Although there were differences in the effects of these compounds, they mainly depressed flight-associated responses, and acted similarly to compounds that block sodium channels and facilitate GABA action.
Extensive transcriptional response associated with seasonal plasticity of butterfly wing patterns.
Daniels, Emily V; Murad, Rabi; Mortazavi, Ali; Reed, Robert D
2014-12-01
In the eastern United States, the buckeye butterfly, Junonia coenia, shows seasonal wing colour plasticity where adults emerging in the spring are tan, while those emerging in the autumn are dark red. This variation can be artificially induced in laboratory colonies, thus making J. coenia a useful model system to examine the mechanistic basis of plasticity. To better understand the developmental basis of seasonal plasticity, we used RNA-seq to quantify transcription profiles associated with development of alternative seasonal wing morphs. Depending on the developmental stage, between 547 and 1420 transfrags were significantly differentially expressed between morphs. These extensive differences in gene expression stand in contrast to the much smaller numbers of differentially expressed transcripts identified in previous studies of genetic wing pattern variation in other species and suggest that environmentally induced phenotypic shifts arise from very broad systemic processes. Analyses of candidate endocrine and pigmentation transcripts revealed notable genes upregulated in the red morph, including several ecdysone-associated genes, and cinnabar, an ommochrome pigmentation gene implicated in colour pattern variation in other butterflies. We also found multiple melanin-related transcripts strongly upregulated in the red morph, including tan and yellow-family genes, leading us to speculate that dark red pigmentation in autumn J. coenia may involve nonommochrome pigments. While we identified several endocrine and pigmentation genes as obvious candidates for seasonal colour morph differentiation, we speculate that the majority of observed expression differences were due to thermal stress response. The buckeye transcriptome provides a basis for further developmental studies of phenotypic plasticity. © 2014 John Wiley & Sons Ltd.
The artificial beetle, or a brief manifesto for engineered biomimicry
NASA Astrophysics Data System (ADS)
Bartl, Michael H.; Lakhtakia, Akhlesh
2015-03-01
The artificial beetle is possibly the Holy Grail for practitioners of engineered biomimicry. An artificial beetle could gather and relay data and images from compromised environments on earth and other planets to decision makers. It could also be used for surveillance of foes and friends alike, and will require ethical foresight and oversight. What would it take to develop an artificial beetle? Several biotemplating techniques can be harnessed for the replication of external structural features of beetle bodies, and thus preserve functionalities such as coloration of the exoskeleton and the hydrophobicity of wings. The body cavity must host a power supply, motors to move the wings for flight, sensors to capture ambient conditions and images, and data transmitters and receivers to communicate with a remote command center. All of these devices must be very small and reliable.
Alexis, Matamoro-Vidal; Isaac, Salazar-Ciudad; David, Houle
2015-01-01
One of the aims of evolutionary developmental biology is to discover the developmental origins of morphological variation. The discipline has mainly focused on qualitative morphological differences (e.g., presence or absence of a structure) between species. Studies addressing subtle, quantitative variation are less common. The Drosophila wing is a model for the study of development and evolution, making it suitable to investigate the developmental mechanisms underlying the subtle quantitative morphological variation observed in nature. Previous reviews have focused on the processes involved in wing differentiation, patterning and growth. Here, we investigate what is known about how the wing achieves its final shape, and what variation in development is capable of generating the variation in wing shape observed in nature. Three major developmental stages need to be considered: larval development, pupariation, and pupal development. The major cellular processes involved in the determination of tissue size and shape are cell proliferation, cell death, oriented cell division and oriented cell intercalation. We review how variation in temporal and spatial distribution of growth and transcription factors affects these cellular mechanisms, which in turn affects wing shape. We then discuss which aspects of the wing morphological variation are predictable on the basis of these mechanisms. PMID:25619644
Structural color and its interaction with other color-producing elements: perspectives from spiders
NASA Astrophysics Data System (ADS)
Hsiung, Bor-Kai; Blackledge, Todd A.; Shawkey, Matthew D.
2014-09-01
Structural color is produced when nanostructures called schemochromes alter light reflected from a surface through different optic principles, in contrast with other types of colors that are produced when pigments selectively absorb certain wavelengths of light. Research on biogenic photonic nanostructures has focused primarily on bird feathers, butterfly wings and beetle elytra, ignoring other diverse groups such as spiders. We argue that spiders are a good model system to study the functions and evolution of colors in nature for the following reasons. First, these colors clearly function in spiders such as the tarantulas outside of sexual selection, which is likely the dominant driver of the evolution of structural colors in birds and butterflies. Second, within more than 44,000 currently known spider species, colors are used in every possible way based on the same sets of relatively simple materials. Using spiders, we can study how colors evolve to serve different functions under a variety of combinations of driving forces, and how those colors are produced within a relatively simple system. Here, we first review the different color-producing materials and mechanisms (i.e., light absorbing, reflecting and emitting) in birds, butterflies and beetles, the interactions between these different elements, and the functions of colors in different organisms. We then summarize the current state of knowledge of spider colors and compare it with that of birds and insects. We then raise questions including: 1. Could spiders use fluorescence as a mechanism to protect themselves from UV radiation, if they do not have the biosynthetic pathways to produce melanins? 2. What functions could color serve for nearly blind tarantulas? 3. Why are only multilayer nanostructures (thus far) found in spiders, while birds and butterflies use many diverse nanostructures? And, does this limit the diversity of structural colors found in spiders? Answering any of these questions in the future will bring spiders to the forefront of the study of structural colors in nature.
Decoding and reconstructing color from responses in human visual cortex.
Brouwer, Gijs Joost; Heeger, David J
2009-11-04
How is color represented by spatially distributed patterns of activity in visual cortex? Functional magnetic resonance imaging responses to several stimulus colors were analyzed with multivariate techniques: conventional pattern classification, a forward model of idealized color tuning, and principal component analysis (PCA). Stimulus color was accurately decoded from activity in V1, V2, V3, V4, and VO1 but not LO1, LO2, V3A/B, or MT+. The conventional classifier and forward model yielded similar accuracies, but the forward model (unlike the classifier) also reliably reconstructed novel stimulus colors not used to train (specify parameters of) the model. The mean responses, averaged across voxels in each visual area, were not reliably distinguishable for the different stimulus colors. Hence, each stimulus color was associated with a unique spatially distributed pattern of activity, presumably reflecting the color selectivity of cortical neurons. Using PCA, a color space was derived from the covariation, across voxels, in the responses to different colors. In V4 and VO1, the first two principal component scores (main source of variation) of the responses revealed a progression through perceptual color space, with perceptually similar colors evoking the most similar responses. This was not the case for any of the other visual cortical areas, including V1, although decoding was most accurate in V1. This dissociation implies a transformation from the color representation in V1 to reflect perceptual color space in V4 and VO1.
The first comprehensive molecular detection of six honey bee viruses in Iran in 2015-2016.
Ghorani, Mohammadreza; Madadgar, Omid; Langeroudi, Arash Ghalyanchi; Rezapanah, Mohammadreza; Nabian, Sedigheh; Akbarein, Hesameddin; Farahani, Reza Kh; Maghsoudloo, Hossein; Abdollahi, Hamed; Forsi, Mohammad
2017-08-01
At least 18 viruses have been reported in the honey bee (Apis mellifera L.). However, severe diseases in honey bees are mainly caused by six viruses, and these are the most important in beekeeping. These viruses include: deformed wing virus (DWV), acute bee paralysis virus (ABPV), chronic bee paralysis virus (CBPV), sacbrood virus (SBV), kashmir bee virus (KBV), and black queen cell virus (BQCV). In this study, we evaluated 89 Iranian honey bee apiaries (during the period 2015-2016) suffering from symptoms of depopulation, sudden collapse, paralysis, or dark coloring, by employing reverse transcription-PCR. Samples were collected from four regions (Mazandaran, Hormozgan, Kurdistan, and Khorasan Razavi) of Iran. Of the 89 apiaries examined, 16 (17.97%), three (3.37%), and three (3.37%) were infected by DWV, ABPV, and CBPV, respectively. The study results for the other viruses (SBV, KBV, and BQCV) were negative. The present study evaluated the presence of the six most important honey bee viruses in bee colonies with suspected infections, and identified remarkable differences in the distribution patterns of the viruses in different geographic regions of Iran.
Confocal imaging of butterfly tissue.
Brunetti, Craig R
2014-01-01
To understand the molecular events responsible for morphological change requires the ability to examine gene expression in a wide range of organisms in addition to model systems to determine how the differences in gene expression correlate with phenotypic differences. There are approximately 12,000 species of butterflies, most, with distinct patterns on their wings. The most important tool for studying gene expression in butterflies is confocal imaging of butterfly tissue by indirect immunofluorescence using either cross-reactive antibodies from closely related species such as Drosophila or developing butterfly-specific antibodies. In this report, we describe how indirect immunofluorescence protocols can be used to visualize protein expression patterns on the butterfly wing imaginal disc and butterfly embryo.
Color and luminance in the perception of 1- and 2-dimensional motion.
Farell, B
1999-08-01
An isoluminant color grating usually appears to move more slowly than a luminance grating that has the same physical speed. Yet a grating defined by both color and luminance is seen as perceptually unified and moving at a single intermediate speed. In experiments measuring perceived speed and direction, it was found that color- and luminance-based motion signals are combined differently in the perception of 1-D motion than they are in the perception of 2-D motion. Adding color to a moving 1-D luminance pattern, a grating, slows its perceived speed. Adding color to a moving 2-D luminance pattern, a plaid made of orthogonal gratings, leaves its perceived speed unchanged. Analogous results occur for the perception of the direction of 2-D motion. The visual system appears to discount color when analyzing the motion of luminance-bearing 2-D patterns. This strategy has adaptive advantages, making the sensing of object motion more veridical without sacrificing the ability to see motion at isoluminance.
Single layer multi-color luminescent display and method of making
NASA Technical Reports Server (NTRS)
Robertson, James B. (Inventor)
1992-01-01
The invention is a multi-color luminescent display comprising an insulator substrate and a single layer of host material, which may be a phosphor deposited thereon that hosts one or more different impurities, therein forming a pattern of selected and distinctly colored phosphors such as blue, green, and red phosphors in a single layer of host material. Transparent electrical conductor means may be provided for subjecting selected portions of the pattern of colored phosphors to an electric field, thereby forming a multi-color, single layer electroluminescent display. A method of forming a multi-color luminescent display includes the steps of depositing on an insulator substrate a single layer of host material, which itself may be a phosphor, with the properties to host varying quantities of different impurities and introducing one or more of said different impurities into selected areas of the said single layer of host material by thermal diffusion or ion implantation to form a pattern of phosphors of different colors in the said single layer of host material.
Color constancy: phenomenal or projective?
Reeves, Adam J; Amano, Kinjiro; Foster, David H
2008-02-01
Naive observers viewed a sequence of colored Mondrian patterns, simulated on a color monitor. Each pattern was presented twice in succession, first under one daylight illuminant with a correlated color temperature of either 16,000 or 4000 K and then under the other, to test for color constancy. The observers compared the central square of the pattern across illuminants, either rating it for sameness of material appearance or sameness of hue and saturation or judging an objective property-that is, whether its change of color originated from a change in material or only from a change in illumination. Average color constancy indices were high for material appearance ratings and binary judgments of origin and low for hue-saturation ratings. Individuals' performance varied, but judgments of material and of hue and saturation remained demarcated. Observers seem able to separate phenomenal percepts from their ontological projections of mental appearance onto physical phenomena; thus, even when a chromatic change alters perceived hue and saturation, observers can reliably infer the cause, the constancy of the underlying surface spectral reflectance.
Brito, Vinícius L. G.; Weynans, Kevin; Sazima, Marlies; Lunau, Klaus
2015-01-01
Floral color changes and retention of old flowers are frequently combined phenomena restricted to the floral guide or single flowers in few-flowered inflorescences. They are thought to increase the attractiveness over long distances and to direct nearby pollinators toward the rewarding flowers. In Tibouchina pulchra, a massively flowering tree, the whole flower changes its color during anthesis. On the first day, the flowers are white and on the next 3 days, they change to pink. This creates a new large-scale color pattern in which the white pre-changed flowers contrast against the pink post-changed ones over the entire tree. We describe the spectral characteristics of floral colors of T. pulchra and test bumblebees’ response to this color pattern when viewed at different angles (simulating long and short distances). The results indicated the role of different color components in bumblebee attraction and the possible scenario in which this flower color pattern has evolved. We tested bumblebees’ preference for simulated trees with 75% pink and 25% white flowers resembling the color patterns of T. pulchra, and trees with green leaves and pink flowers (control) in long-distance approach. We also compared an artificial setting with three pink flowers and one white flower (T. pulchra model) against four pink flowers with white floral guides (control) in short-distance approach. Bumblebees spontaneously preferred the simulated T. pulchra patterns in both approaches despite similar reward. Moreover, in short distances, pollinator visits to peripheral, non-rewarding flowers occurred only half as frequently in the simulated T. pulchra when compared to the control. Thefore, this exceptional floral color change and the retention of old flowers in T. pulchra favors the attraction of pollinators over long distances in a deception process while it honestly directs them toward the rewarding flowers at short distances possibly exploring their innate color preferences. PMID:26052335
Self-aligned quadruple patterning-compliant placement
NASA Astrophysics Data System (ADS)
Nakajima, Fumiharu; Kodama, Chikaaki; Nakayama, Koichi; Nojima, Shigeki; Kotani, Toshiya
2015-03-01
Self-Aligned Quadruple Patterning (SAQP) will be one of the leading candidates for sub-14nm node and beyond. However, compared with triple patterning, making a feasible standard cell placement has following problems. (1) When coloring conflicts occur between two adjoining cells, they may not be solved easily since SAQP layout has stronger coloring constraints. (2) SAQP layout cannot use stitch to solve coloring conflict. In this paper, we present a framework of SAQP-aware standard cell placement considering the above problems. When standard cell is placed, the proposed method tries to solve coloring conflicts between two cells by exchanging two of three colors. If some conflicts remain between adjoining cells, dummy space will be inserted to keep coloring constraints of SAQP. We show some examples to confirm effectiveness of the proposed framework. To our best knowledge, this is the first framework of SAQP-aware standard cell placement.
Márquez, E J; Saldamando-Benjumea, C I
2013-09-01
Habitat change in Rhodnius spp may represent an environmental challenge for the development of the species, particularly when feeding frequency and population density vary in nature. To estimate the effect of these variables in stability on development, the degree of directional asymmetry (DA) and fluctuating asymmetry (FA) in the wing size and shape of R. prolixus and R. robustus-like were measured under laboratory controlled conditions. DA and FA in wing size and shape were significant in both species, but their variation patterns showed both inter-specific and sexual dimorphic differences in FA of wing size and shape induced by nutrition stress. These results suggest different abilities of the genotypes and sexes of two sylvatic and domestic genotypes of Rhodnius to buffer these stress conditions. However, both species showed non-significant differences in the levels of FA between treatments that simulated sylvan vs domestic conditions, indicating that the developmental noise did not explain the variation in wing size and shape found in previous studies. Thus, this result confirm that the variation in wing size and shape in response to treatments constitute a plastic response of these genotypes to population density and feeding frequency.
Infrared Imaging Of Flows Seeded With SF6
NASA Technical Reports Server (NTRS)
Manuel, Gregory S.; Daryabeigi, Kamran; Alderfer, David W.; Obara, Clifford J.
1993-01-01
Novel technique enables repeated measurements of flow patterns during flight. Wing-tip vorticity studied in flight by observing infrared emissions from SF6 gas entrained in wing-tip flow. System makes vortical flows visible throughout all altitude and speed ranges of all subsonic aircraft. Also useful for transonic and supersonic speeds. Primary application is testing of aircraft in flight, also proves useful in testing fast land vehicles and structures or devices subject to strong winds.
Resolution for color photography
NASA Astrophysics Data System (ADS)
Hubel, Paul M.; Bautsch, Markus
2006-02-01
Although it is well known that luminance resolution is most important, the ability to accurately render colored details, color textures, and colored fabrics cannot be overlooked. This includes the ability to accurately render single-pixel color details as well as avoiding color aliasing. All consumer digital cameras on the market today record in color and the scenes people are photographing are usually color. Yet almost all resolution measurements made on color cameras are done using a black and white target. In this paper we present several methods for measuring and quantifying color resolution. The first method, detailed in a previous publication, uses a slanted-edge target of two colored surfaces in place of the standard black and white edge pattern. The second method employs the standard black and white targets recommended in the ISO standard, but records these onto the camera through colored filters thus giving modulation between black and one particular color component; red, green, and blue color separation filters are used in this study. The third method, conducted at Stiftung Warentest, an independent consumer organization of Germany, uses a whitelight interferometer to generate fringe pattern targets of varying color and spatial frequency.
Measurements of Flow Rate and Trajectory of Aircraft Tire-Generated Water Spray
NASA Technical Reports Server (NTRS)
Daugherty, Robert H.; Stubbs, Sandy M.
1987-01-01
An experimental investigation was conducted at the NASA Langley Research Center to measure the flow rate and trajectory of water spray generated by an aircraft tire operating on a flooded runway. Tests were conducted in the Hydrodynamics Research Facility and made use of a partial airframe and a nose tire from a general aviation aircraft. Nose tires from a commercial transport aircraft were also used. The effects of forward speed, tire load, and water depth on water spray patterns were evaluated by measuring the amount and location of water captured by an array of tubes mounted behind the test tire. Water ejected from the side of the tire footprint had the most significant potential for ingestion into engine inlets. A lateral wake created on the water surface by the rolling tire can dominate the shape of the spray pattern as the distance aft of the tire is increased. Forward speed increased flow rates and moved the spray pattern inboard. Increased tire load caused the spray to become less dense. Near the tire, increased water depths caused flow rates to increase. Tests using a fuselage and partial wing along with the nose gear showed that for certain configurations, wing aerodynamics can cause a concentration of spray above the wing.
Chromatic induction in space and time.
Coia, Andrew J; Shevell, Steven K
2018-04-01
The color appearance of a light depends on variation in the complete visual field over both space and time. In the spatial domain, a chromatic stimulus within a patterned chromatic surround can appear a different hue than the same stimulus within a uniform surround. In the temporal domain, a stimulus presented as an element of a continuously changing chromaticity can appear a different color compared to the identical stimulus, presented simultaneously but viewed alone. This is the flash-lag effect for color, which has an analog in the domain of motion: a pulsed object seen alone can appear to lag behind an identical pulsed object that is an element of a motion sequence. Studies of the flash-lag effect for motion have considered whether it is mediated by a neural representation for the moving physical stimulus or, alternatively, for the perceived motion. The current study addresses this question for the flash-lag effect for color by testing whether the color flash lag depends on a representation of only the changing chromatic stimulus or, alternatively, its color percept, which can be altered by chromatic induction. baseline measurements for spatial chromatic induction determined the chromaticity of a flashed ring within a uniform surround that matched a flashed ring within a patterned surround. Baseline measurements for the color flash-lag effect determined the chromaticity of a pulsed ring presented alone (within a uniform surround) that matched a pulsed ring presented in a sequence of changing chromaticity over time (also within a uniform surround). Finally, the main experiments combined chromatic induction from a patterned surround and the flash-lag effect, in three conditions: (1) both the changing and pulsed rings were within a patterned chromatic surround; (2) the changing ring was within a patterned surround and the pulsed ring within a uniform surround; and (3) the changing ring was within a uniform surround and the pulsed ring within a patterned surround. the flash-lag measurements for a changing chromaticity were affected by perceptual changes induced by the surrounding chromatic pattern. Thus, the color shifts induced by a chromatic surround are incorporated in the neural representation mediating the flash-lag effect for color.
Brzozowski, Frances; Roscoe, Jennifer; Parsons, Kevin; Albertson, Craig
2012-06-01
East African cichlids are renowned for their propensity to radiate, and variation in color patterns accounts for much of endemic cichlid diversity. Sexual dimorphism in color among cichlid species likely represents the outcome of different selective regimes acting on each sex, and is a classic example of sexual conflict. It is generally assumed that this conflict has been mitigated through the evolution of sex-linked color polymorphisms. Here, we propose that the evolution of sex-specific differences in levels of color trait integration may represent an additional mechanism through which sexual conflict has been resolved in this group. Specifically, we predict: (1) that general patterns of integration are influenced by early developmental events and thus conserved across sexes and (2) that male color is less integrated than females, and thus more evolvable in terms of producing an elaborate palette (i.e., in response to sexual selection), whereas female color is more integrated, facilitating wholesale shifts in color for background matching (i.e., in response to natural selection for crypsis). We tested these hypotheses using an F(2) design to compare the segregation of male and female color patterns. Both exploratory methods and hypothesis-driven analyses of integration demonstrate that the covariance structure of color traits in males and females is distinct, and that males are significantly less integrated than females. We suggest that the ability of species to promote different levels, and to a lesser extent patterns, of phenotypic integration between males and females may have contributed to the evolutionary success of this group. © 2012 WILEY PERIODICALS, INC.
Cross-Cultural Color-Odor Associations
Levitan, Carmel A.; Ren, Jiana; Woods, Andy T.; Boesveldt, Sanne; Chan, Jason S.; McKenzie, Kirsten J.; Dodson, Michael; Levin, Jai A.; Leong, Christine X. R.; van den Bosch, Jasper J. F.
2014-01-01
Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor), statistical reasons (i.e., covariance in experience), and/or semantically-mediated reasons (i.e., stemming from language). The present study probed this question by testing color-odor correspondences in 6 different cultural groups (Dutch, Netherlands-residing-Chinese, German, Malay, Malaysian-Chinese, and US residents), using the same set of 14 odors and asking participants to make congruent and incongruent color choices for each odor. We found consistent patterns in color choices for each odor within each culture, showing that participants were making non-random color-odor matches. We used representational dissimilarity analysis to probe for variations in the patterns of color-odor associations across cultures; we found that US and German participants had the most similar patterns of associations, followed by German and Malay participants. The largest group differences were between Malay and Netherlands-resident Chinese participants and between Dutch and Malaysian-Chinese participants. We conclude that culture plays a role in color-odor crossmodal associations, which likely arise, at least in part, through experience. PMID:25007343
NASA Astrophysics Data System (ADS)
Oliker, Vladimir I.; Cherkasskiy, Boris
2014-09-01
Structural color is produced when nanostructures called schemochromes alter light reflected from a surface through different optic principles, in contrast with other types of colors that are produced when pigments selectively absorb certain wavelengths of light. Research on biogenic photonic nanostructures has focused primarily on bird feathers, butterfly wings and beetle elytra, ignoring other diverse groups such as spiders. We argue that spiders are a good model system to study the functions and evolution of colors in nature for the following reasons. First, these colors clearly function in spiders such as the tarantulas outside of sexual selection, which is likely the dominant driver of the evolution of structural colors in birds and butterflies. Second, within more than 44,000 currently known spider species, colors are used in every possible way based on the same sets of relatively simple materials. Using spiders, we can study how colors evolve to serve different functions under a variety of combinations of driving forces, and how those colors are produced within a relatively simple system. Here, we first review the different color-producing materials and mechanisms (i.e., light absorbing, reflecting and emitting) in birds, butterflies and beetles, the interactions between these different elements, and the functions of colors in different organisms. We then summarize the current state of knowledge of spider colors and compare it with that of birds and insects. We then raise questions including: 1. Could spiders use fluorescence as a mechanism to protect themselves from UV radiation, if they do not have the biosynthetic pathways to produce melanins? 2. What functions could color serve for nearly blind tarantulas? 3. Why are only multilayer nanostructures (thus far) found in spiders, while birds and butterflies use many diverse nanostructures? And, does this limit the diversity of structural colors found in spiders? Answering any of these questions in the future will bring spiders to the forefront of the study of structural colors in nature.
NASA Technical Reports Server (NTRS)
Parsons-Wingerter, Patricia A.; Weitzel, Alexander; Vyas, Ruchi J.; Murray, Matthew C.; Wyatt, Sarah E.
2016-01-01
One fundamental requirement shared by humans with all higher terrestrial life forms, including insect wings, higher land plants and other vertebrates, is a complex, fractally branching vascular system. NASA's VESsel GENeration Analysis (VESGEN) software maps and quantifies vascular trees, networks, and tree-network composites according to weighted physiological rules such as vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport requires a complex distributed system of highly regulated laminar flow. Microvascular branching rules within vertebrates, dicot leaves and the other organisms therefore display many similarities. One unifying perspective is that vascular patterning offers a useful readout that necessarily integrates complex molecular signaling pathways. VESGEN has elucidated changes in vascular pattern resulting from inflammatory, stress response, developmental and other signaling within numerous tissues and major model organisms studied for Space Biology. For a new VESGEN systems approach, we analyzed differential gene expression in leaves of Arabidopsis thaliana reported by GeneLab (GLDS-7) for spaceflight. Vascular-related changes in leaf gene expression were identified that can potentially be phenocopied by mutants in ground-based experiments. To link transcriptional, protein and other molecular change with phenotype, alterations in the Euclidean and dynamic dimensions (x,y,t) of vascular patterns for Arabidopsis leaves and other model species are being co-localized with signaling patterns of single molecular expression analyzed as information dimensions (i,j,k,...). Previously, Drosophila microarray data returned from space suggested significant changes in genes related to wing venation development that include EGF, Notch, Hedghog, Wingless and Dpp signaling. Phenotypes of increasingly abnormal ectopic wing venation in the (non-spaceflight) Drosophila wing generated by overexpression of a Notch antagonist were analyzed by VESGEN. Other VESGEN research applications include the mouse retina, GI and coronary vessels, avian placental analogs and translational studies in the astronaut retina related to health challenges for long-duration missions.
Traits and evolution of wing venation pattern in paraneopteran insects.
Nel, André; Prokop, Jakub; Nel, Patricia; Grandcolas, Philippe; Huang, Di-Ying; Roques, Patrick; Guilbert, Eric; Dostál, Ondřej; Szwedo, Jacek
2012-05-01
Two different patterns of wing venation are currently supposed to be present in each of the three orders of Paraneoptera. This is unlikely compared with the situation in other insects where only one pattern exists per order. We propose for all Paraneoptera a new and unique interpretation of wing venation pattern, assuming that the convex cubitus anterior gets fused with the common stem of median and radial veins at or very near to wing base, after separation from concave cubitus posterior, and re-emerges more distally from R + M stem. Thereafter, the vein between concave cubitus posterior and CuA is a specialized crossvein called "cua-cup," proximally concave and distally convex. We show that despite some variations, that is, cua-cup can vary from absent to hypertrophic; CuA can re-emerge together with M or not, or even completely disappear, this new interpretation explains all situations among all fossil and recent paraneopteran lineages. We propose that the characters "CuA fused in a common stem with R and M"and "presence of specialized crossvein cua-cup" are venation apomorphies that support the monophyly of the Paraneoptera. In the light of these characters, we reinterpret several Palaeozoic and early Mesozoic fossils that were ascribed to Paraneoptera, and confirm the attribution of several to this superorder as well as possible attribution of Zygopsocidae (Zygopsocus permianus Tillyard, 1935) as oldest Psocodea. We discuss the situation in extinct Hypoperlida and Miomoptera, suggesting that both orders could well be polyphyletic, with taxa related to Archaeorthoptera, Paraneoptera, or even Holometabola. The Carboniferous Protoprosbolidae is resurrected and retransferred into the Paraneoptera. The genus Lithoscytina is restored. The miomopteran Eodelopterum priscum Schmidt, 1962 is newly revised and considered as a fern pinnule. In addition, the new paraneopteran Bruayaphis oudardi gen. nov. et sp. nov. is described fromthe Upper Carboniferous of France (see Supporting Information). Copyright © 2011 Wiley Periodicals, Inc.
Imperfect chemical female mimicry in males of the ant Cardiocondyla obscurior
NASA Astrophysics Data System (ADS)
Cremer, Sylvia; D'Ettorre, Patrizia; Drijfhout, Falko P.; Sledge, Matthew F.; Turillazzi, Stefano; Heinze, Jürgen
2008-11-01
Winged and wingless males coexist in the ant Cardiocondyla obscurior. Wingless (“ergatoid”) males never leave their maternal colony and fight remorselessly among each other for the access to emerging females. The peaceful winged males disperse after about 10 days, but beforehand also mate in the nest. In the first 5 days of their life, winged males perform a chemical female mimicry that protects them against attack and even makes them sexually attractive to ergatoid males. When older, the chemical profile of winged males no longer matches that of virgin females; nevertheless, they are still tolerated, which so far has been puzzling. Contrasting this general pattern, we have identified a single aberrant colony in which all winged males were attacked and killed by the ergatoid males. A comparative analysis of the morphology and chemical profile of these untypical attacked winged males and the tolerated males from several normal colonies revealed that normal old males are still performing some chemical mimicry to the virgin queens, though less perfect than in their young ages. The anomalous attacked winged males, on the other hand, had a very different odour to the females. Our study thus exemplifies that the analysis of rare malfunctioning can add valuable insight on functioning under normal conditions and allows the conclusion that older winged males from normal colonies of the ant C. obscurior are guarded through an imperfect chemical female mimicry, still close enough to protect against attacks by the wingless fighters yet dissimilar enough not to elicit their sexual interest.
Genome-wide introgression among distantly related Heliconius butterfly species.
Zhang, Wei; Dasmahapatra, Kanchon K; Mallet, James; Moreira, Gilson R P; Kronforst, Marcus R
2016-02-27
Although hybridization is thought to be relatively rare in animals, the raw genetic material introduced via introgression may play an important role in fueling adaptation and adaptive radiation. The butterfly genus Heliconius is an excellent system to study hybridization and introgression but most studies have focused on closely related species such as H. cydno and H. melpomene. Here we characterize genome-wide patterns of introgression between H. besckei, the only species with a red and yellow banded 'postman' wing pattern in the tiger-striped silvaniform clade, and co-mimetic H. melpomene nanna. We find a pronounced signature of putative introgression from H. melpomene into H. besckei in the genomic region upstream of the gene optix, known to control red wing patterning, suggesting adaptive introgression of wing pattern mimicry between these two distantly related species. At least 39 additional genomic regions show signals of introgression as strong or stronger than this mimicry locus. Gene flow has been on-going, with evidence of gene exchange at multiple time points, and bidirectional, moving from the melpomene to the silvaniform clade and vice versa. The history of gene exchange has also been complex, with contributions from multiple silvaniform species in addition to H. besckei. We also detect a signature of ancient introgression of the entire Z chromosome between the silvaniform and melpomene/cydno clades. Our study provides a genome-wide portrait of introgression between distantly related butterfly species. We further propose a comprehensive and efficient workflow for gene flow identification in genomic data sets.
Morphological outcomes of gynandromorphism in Lycaeides butterflies (Lepidoptera: Lycaenidae).
Jahner, Joshua P; Lucas, Lauren K; Wilson, Joseph S; Forister, Matthew L
2015-01-01
The genitalia of male insects have been widely used in taxonomic identification and systematics and are potentially involved in maintaining reproductive isolation between species. Although sexual selection has been invoked to explain patterns of morphological variation in genitalia among populations and species, developmental plasticity in genitalia likely contributes to observed variation but has been rarely examined, particularly in wild populations. Bilateral gynandromorphs are individuals that are genetically male on one side of the midline and genetically female on the other, while mosaic gynandromorphs have only a portion of their body developing as the opposite sex. Gynandromorphs might offer unique insights into developmental plasticity because individuals experience abnormal cellular interactions at the genitalic midline. In this study, we compare the genitalia and wing patterns of gynandromorphic Anna and Melissa blue butterflies, Lycaeides anna (Edwards) (formerly L. idas anna) and L. melissa (Edwards) (Lepidoptera: Lycaenidae), to the morphology of normal individuals from the same populations. Gynandromorph wing markings all fell within the range of variation of normal butterflies; however, a number of genitalic measurements were outliers when compared with normal individuals. From these results, we conclude that the gynandromorphs' genitalia, but not wing patterns, can be abnormal when compared with normal individuals and that the gynandromorphic genitalia do not deviate developmentally in a consistent pattern across individuals. Finally, genetic mechanisms are considered for the development of gynandromorphism in Lycaeides butterflies. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.
Phytogeographic patterns and cryptic diversity in an aposematic toad from NW Argentina.
Clemente-Carvalho, Rute B; Vaira, Marcos; King, Laura E; Koscinski, Daria; Bonansea, Maria I; Lougheed, Stephen C
2017-11-01
The Yungas Redbelly Toad, Melanophryniscus rubriventris, is patchily distributed in Argentina, confined to the upland portion (1000-2000m above sea level) of the montane forests of northern and central regions of Salta, and in central-eastern and south-eastern Jujuy. This species is known for its striking aposematic color variation across its geographic distribution, and was once treated as a complex of three subspecies based on distinctive color patterns. Here we assess the geographical genetic variation within M. rubriventris and quantify divergence in color and pattern among individuals sampled from Northwestern Argentina. We compare multi-gene phylogeography of M. rubriventris to patterns of dorsal and ventral coloration to test whether evolutionary affinities predict variation in warning color. Our results reveal two well-supported species lineages: one confined to the extreme northern portion of our sampling area, and the other extending over most of the Argentine portion of the species' range, within which there are two populations. However, these well-supported evolutionary relationships do not mirror the marked variation in warning coloration. This discordance between DNA genealogy and warning color variation may reflect selection brought about by differences in local predation pressures, potentially coupled with effects of sexual selection and thermoregulation. Copyright © 2017 Elsevier Inc. All rights reserved.
Pressure-Sensitive Paint Investigation of Double-Delta Wing Vortex Flow Manipulation
NASA Technical Reports Server (NTRS)
Erickson, Gary E.; Gonzalez, Hugo A.
2004-01-01
A pressure-sensitive paint (PSP) technique was applied in a wind tunnel experiment in the NASA Langley Research Center 8-Foot Transonic Pressure Tunnel to quantify the effect of wing fillets on the global vortex-induced surface static pressure field about a sharp leading-edge 76o/40o double delta wing, or strake-wing, model at subsonic and transonic speeds. Global calibrations of the PSP were obtained at M = 0.50, 0.70, 0.85, 0.95, and 1.20, a Reynolds number per unit length of 2.0 million, and angles of attack from 10 degrees to 20 degrees using an in-situ method featuring the simultaneous acquisition of electronically-scanned pressures (ESP) at discrete locations on the model. The mean error in the PSP measurements relative to the ESP data was approximately 2 percent or less at M = 0.50 to 0.85 but increased to several percent at M =0.95 and 1.20. The PSP pressure distributions and pseudo-colored planform view pressure maps clearly revealed the vortex-induced pressure signatures at all Mach numbers and angles of attack. Small fillets having a parabolic or diamond planform situated at the strake-wing intersection were designed to manipulate the vortical flows by, respectively, removing the leading-edge discontinuity or introducing additional discontinuities. The fillets caused global changes in the vortex-dominated surface pressure field that were effectively captured in the PSP measurements. The vortex surface pressure signatures were compared to available off-surface vortex cross-flow structures obtained using a laser vapor screen (LVS) flow visualization technique. The fillet effects on the PSP pressure distributions and the observed leading-edge vortex flow characteristics were consistent with the trends in the measured lift, drag, and pitching moment coefficients.
Pressure-Sensitive Paint Investigation of Double-Delta Wing Vortex Flow Manipulation
NASA Technical Reports Server (NTRS)
Erickson, Gary E.; Gonzalez, Hugo A.
2005-01-01
A pressure-sensitive paint (PSP) technique was applied in a wind tunnel experiment in the NASA Langley Research Center 8-Foot Transonic Pressure Tunnel to quantify the effect of wing fillets on the global vortex-induced surface static pressure field about a sharp leading-edge 76 deg/40 deg double delta wing, or strake-wing, model at subsonic and transonic speeds. Global calibrations of the PSP were obtained at M = 0.50, 0.70, 0.85, 0.95, and 1.20, a Reynolds number per unit length of 2.0 million, and angles of attack from 10 degrees to 30 degrees using an in-situ method featuring the simultaneous acquisition of electronically-scanned pressures (ESP) at discrete locations on the model. The mean error in the PSP measurements relative to the ESP data was approximately 2 percent or less at M = 0.50 to 0.85 but increased to several percent at M = 0.95 and 1.20. The PSP pressure distributions and pseudo-colored planform view pressure maps clearly revealed the vortex-induced pressure signatures at all Mach numbers and angles of attack. Small fillets having a parabolic or diamond planform situated at the strake-wing intersection were designed to manipulate the vortical flows by, respectively, removing the leading-edge discontinuity or introducing additional discontinuities. The fillets caused global changes in the vortex-dominated surface pressure field that were effectively captured in the PSP measurements. The vortex surface pressure signatures were compared to available off-surface vortex cross-flow structures obtained using a laser vapor screen (LVS) flow visualization technique. The fillet effects on the PSP pressure distributions and the observed leading-edge vortex flow characteristics were consistent with the trends in the measured lift, drag, and pitching moment coefficients.
Conjugated polymer dots for ultra-stable full-color fluorescence patterning.
Chang, Kaiwen; Liu, Zhihe; Chen, Haobin; Sheng, Lan; Zhang, Sean Xiao-An; Chiu, Daniel T; Yin, Shengyan; Wu, Changfeng; Qin, Weiping
2014-11-12
Stable full-color fluorescence patterning are achieved by multicolor polymer-dot inks. The fluorescent patterns show extraordinary stability upon various treatments, offering a superior combination of bright fluorescence, excellent photostability, chemical resistance, and eco-friendship. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Color preference in red-green dichromats.
Álvaro, Leticia; Moreira, Humberto; Lillo, Julio; Franklin, Anna
2015-07-28
Around 2% of males have red-green dichromacy, which is a genetic disorder of color vision where one type of cone photoreceptor is missing. Here we investigate the color preferences of dichromats. We aim (i) to establish whether the systematic and reliable color preferences of normal trichromatic observers (e.g., preference maximum at blue, minimum at yellow-green) are affected by dichromacy and (ii) to test theories of color preference with a dichromatic sample. Dichromat and normal trichromat observers named and rated how much they liked saturated, light, dark, and focal colors twice. Trichromats had the expected pattern of preference. Dichromats had a reliable pattern of preference that was different to trichromats, with a preference maximum rather than minimum at yellow and a much weaker preference for blue than trichromats. Color preference was more affected in observers who lacked the cone type sensitive to long wavelengths (protanopes) than in those who lacked the cone type sensitive to medium wavelengths (deuteranopes). Trichromats' preferences were summarized effectively in terms of cone-contrast between color and background, and yellow-blue cone-contrast could account for dichromats' pattern of preference, with some evidence for residual red-green activity in deuteranopes' preference. Dichromats' color naming also could account for their color preferences, with colors named more accurately and quickly being more preferred. This relationship between color naming and preference also was present for trichromat males but not females. Overall, the findings provide novel evidence on how dichromats experience color, advance the understanding of why humans like some colors more than others, and have implications for general theories of aesthetics.
Color preference in red–green dichromats
Álvaro, Leticia; Moreira, Humberto; Lillo, Julio; Franklin, Anna
2015-01-01
Around 2% of males have red–green dichromacy, which is a genetic disorder of color vision where one type of cone photoreceptor is missing. Here we investigate the color preferences of dichromats. We aim (i) to establish whether the systematic and reliable color preferences of normal trichromatic observers (e.g., preference maximum at blue, minimum at yellow-green) are affected by dichromacy and (ii) to test theories of color preference with a dichromatic sample. Dichromat and normal trichromat observers named and rated how much they liked saturated, light, dark, and focal colors twice. Trichromats had the expected pattern of preference. Dichromats had a reliable pattern of preference that was different to trichromats, with a preference maximum rather than minimum at yellow and a much weaker preference for blue than trichromats. Color preference was more affected in observers who lacked the cone type sensitive to long wavelengths (protanopes) than in those who lacked the cone type sensitive to medium wavelengths (deuteranopes). Trichromats’ preferences were summarized effectively in terms of cone-contrast between color and background, and yellow-blue cone-contrast could account for dichromats’ pattern of preference, with some evidence for residual red–green activity in deuteranopes’ preference. Dichromats’ color naming also could account for their color preferences, with colors named more accurately and quickly being more preferred. This relationship between color naming and preference also was present for trichromat males but not females. Overall, the findings provide novel evidence on how dichromats experience color, advance the understanding of why humans like some colors more than others, and have implications for general theories of aesthetics. PMID:26170287
An intergeneric hybrid wood warbler (Seiurus x Dendroica)
Short, L.L.; Robbins, Chandler S.
1967-01-01
Wild hybrid birds are always of interest with regard to our understanding of the variation encountered in nature. They may also be of ore or less taxonomic significance, depending on the frequency of their occurrence and other factors. We herein report and describe an apparent hybrid Northern Waterthrush (Seiurus noveboracensis) x Blackpoll Warbler (Dendroica striata) taken by Robbins at Ocean City, Maryland, on 17 September 1965. The bird (U.S. National Museum, no. 481595), an immature male with no fat, weighed 13.7 g and had apparently normal testes, each measuring 2.0 x 0.5 mm. The hybrid was taken in a net situated close to the ground, inland from the beach north of Ocean City; both Northern Waterthrushes and Blackpoll Warblers were caught the same day in the same net.The hybrid has the general appearance of a large, dark, immature wood warbler of the genus Dendroica. It shows a peculiar color pattern – it is streaked on its breast somewhat like a Cape May Warbler (D. tigrine), is dark olive with indistinct streaks on its back, and has distinct buffy superciliary stripes, narrowly barred wings, a yellowish white abdomen, long white under tail coverts, and an almost unmarked dark tail. The specimen resembles a Blackpoll Warbler in the length of its wings, tail, and bill, but it has longer legs and toes than members of that species.We are indebted to Mrs. Roxie C. Laybourne, David Bridge, and Paul Slud for useful suggestions, and to Kenneth C. Parkes for a helpful reading of the manuscript. The birds were banded at the Operation Recovery banding station by Robbins, Mrs. Richard D. Cole, Mrs. Herbert M. Church, William S. Clark, Mr. and Mrs. Herman F. Kuch, and Mr. and Mrs. Aldridge pepper.
Scott, Brittney R; Yang, Xiang; Geornaras, Ifigenia; Delmore, Robert J; Woerner, Dale R; Reagan, James O; Morgan, J Brad; Belk, Keith E
2015-11-01
Studies were conducted to evaluate the efficacy of a commercial blend of sulfuric acid and sodium sulfate (SSS) in reducing Salmonella on inoculated whole chilled chicken wings and to compare its efficacy to peroxyacetic acid (PAA) and cetylpyridinium chloride (CPC). Wings were spot inoculated (5 to 6 log CFU/ml of sample rinsate) with a five-strain mixture of novobiocin- and nalidixic acid-resistant Salmonella and then left untreated (control) or treated by immersing individual wings in 350 ml of antimicrobial solution. An initial study evaluated two treatment immersion times, 10 and 20 s, of SSS (pH 1.1) and compared cell recoveries following rinsing of treated samples with buffered peptone water or Dey/Engley neutralizing broth. In a second study, inoculated wings were treated with SSS (pH 1.1; 20 s), PAA (700 ppm, 20 s), or CPC (4,000 ppm, 10 s) and analyzed for survivors immediately after treatment (0 h) and after 24 h of aerobic storage at 4°C. Color and pH analyses were also conducted in the latter study. Recovery of Salmonella survivors following treatment with SSS (10 or 20 s) was not (P ≥ 0.05) affected by the type of cell recovery rinse solution (buffered peptone water or Dey/Engley neutralizing broth), but there was an effect (P < 0.05) of SSS treatment time. Immersion of samples for 10 or 20 s in SSS resulted in pathogen reductions of 0.8 to 0.9 and 1.1 to 1.2 log CFU/ml, respectively. Results of the second study showed that there was an interaction (P < 0.05) between antimicrobial type and storage time. Efficacy against Salmonella at 0 h increased in the order CPC , SSS , PAA; however, after 24 h of aerobic storage, pathogen counts of SSS- and PAA-treated wings did not differ (P ≥ 0.05). Overall, the results indicated that SSS applied at pH 1.1 for 20 s was an effective antimicrobial intervention to reduce Salmonella contamination on chicken wings.
Smart wing rotation and trailing-edge vortices enable high frequency mosquito flight
Bomphrey, Richard J.; Nakata, Toshiyuki; Phillips, Nathan; Walker, Simon M.
2017-01-01
Summary Mosquitoes exhibit unique wing kinematics; their long, slender wings flap at remarkably high frequencies for their size (>800 Hz) and with lower stroke amplitudes than any other insect group1. This shifts weight support away from the translation-dominated, aerodynamic mechanisms used by most insects2, as well as by helicopters and aeroplanes, towards poorly understood rotational mechanisms that occur when pitching at the end of each half-stroke. Here we report wing kinematics and solve the full Navier-Stokes equations using computational fluid dynamics with overset grids and validate our results with in vivo flow measurements. We show that, while familiar separated flow patterns are used by mosquitoes, much of the aerodynamic force that supports their weight is generated in a manner unlike any previously described flying animal. In total, there are three key features: leading-edge vortices (a well-known mechanism that appears to be almost ubiquitous in insect flight), trailing-edge vortices caused by a novel form of wake capture at stroke reversal, and rotational drag. The two new elements are largely independent of the wing velocity, instead relying on rapid changes in the pitch angle (wing rotation) at the end of each half stroke, and are therefore relatively immune to the shallow flapping amplitude. Moreover, these mechanisms are particularly well-suited to high-aspect ratio mosquito wings. PMID:28355184
Smart wing rotation and trailing-edge vortices enable high frequency mosquito flight
NASA Astrophysics Data System (ADS)
Bomphrey, Richard J.; Nakata, Toshiyuki; Phillips, Nathan; Walker, Simon M.
2017-03-01
Mosquitoes exhibit unusual wing kinematics; their long, slender wings flap at remarkably high frequencies for their size (>800 Hz)and with lower stroke amplitudes than any other insect group. This shifts weight support away from the translation-dominated, aerodynamic mechanisms used by most insects, as well as by helicopters and aeroplanes, towards poorly understood rotational mechanisms that occur when pitching at the end of each half-stroke. Here we report free-flight mosquito wing kinematics, solve the full Navier-Stokes equations using computational fluid dynamics with overset grids, and validate our results with in vivo flow measurements. We show that, although mosquitoes use familiar separated flow patterns, much of the aerodynamic force that supports their weight is generated in a manner unlike any previously described for a flying animal. There are three key features: leading-edge vortices (a well-known mechanism that appears to be almost ubiquitous in insect flight), trailing-edge vortices caused by a form of wake capture at stroke reversal, and rotational drag. The two new elements are largely independent of the wing velocity, instead relying on rapid changes in the pitch angle (wing rotation) at the end of each half-stroke, and they are therefore relatively immune to the shallow flapping amplitude. Moreover, these mechanisms are particularly well suited to high aspect ratio mosquito wings.
NASA Technical Reports Server (NTRS)
Mineck, Raymond E.; Vijgen, Paul M. H. W.
1993-01-01
Three planar, untwisted wings with the same elliptical chord distribution but with different curvatures of the quarter-chord line were tested in the Langley 8-Foot Transonic Pressure Tunnel (8-ft TPT) and the Langley 7- by 10-Foot High-Speed Tunnel (7 x 10 HST). A fourth wing with a rectangular planform and the same projected area and span was also tested. Force and moment measurements from the 8-ft TPT tests are presented for Mach numbers from 0.3 to 0.5 and angles of attack from -4 degrees to 7 degrees. Sketches of the oil-flow patterns on the upper surfaces of the wings and some force and moment measurements from the 7 x 10 HST tests are presented at a Mach number of 0.5. Increasing the curvature of the quarter-chord line makes the angle of zero lift more negative but has little effect on the drag coefficient at zero lift. The changes in lift-curve slope and in the Oswald efficiency factor with the change in curvature of the quarter-chord line (wingtip location) indicate that the elliptical wing with the unswept quarter-chord line has the lowest lifting efficiency and the elliptical wing with the unswept trailing edge has the highest lifting efficiency; the crescent-shaped planform wing has an efficiency in between.
Shang, Feng; Ding, Bi-Yue; Xiong, Ying; Dou, Wei; Wei, Dong; Jiang, Hong-Bo; Wei, Dan-Dan; Wang, Jin-Jun
2016-01-01
Winged and wingless morphs in insects represent a trade-off between dispersal ability and reproduction. We studied key genes associated with apterous and alate morphs in Toxoptera citricida (Kirkaldy) using RNAseq, digital gene expression (DGE) profiling, and RNA interference. The de novo assembly of the transcriptome was obtained through Illumina short-read sequencing technology. A total of 44,199 unigenes were generated and 27,640 were annotated. The transcriptomic differences between alate and apterous adults indicated that 279 unigenes were highly expressed in alate adults, whereas 5,470 were expressed at low levels. Expression patterns of the top 10 highly expressed genes in alate adults agreed with wing bud development trends. Silencing of the lipid synthesis and degradation gene (3-ketoacyl-CoA thiolase, mitochondrial-like) and glycogen genes (Phosphoenolpyruvate carboxykinase [GTP]-like and Glycogen phosphorylase-like isoform 2) resulted in underdeveloped wings. This suggests that both lipid and glycogen metabolism provide energy for aphid wing development. The large number of sequences and expression data produced from the transcriptome and DGE sequencing, respectively, increases our understanding of wing development mechanisms. PMID:27577531
Median Hetero-Associative Memories Applied to the Categorization of True-Color Patterns
NASA Astrophysics Data System (ADS)
Vázquez, Roberto A.; Sossa, Humberto
Median associative memories (MED-AMs) are a special type of associative memory based on the median operator. This type of associative model has been applied to the restoration of gray scale images and provides better performance than other models, such as morphological associative memories, when the patterns are altered with mixed noise. Despite of his power, MED-AMs have not been applied in problems involving true-color patterns. In this paper we describe how a median hetero-associative memory (MED-HAM) could be applied in problems that involve true-color patterns. A complete study of the behavior of this associative model in the restoration of true-color images is performed using a benchmark of 14400 images altered by different type of noises. Furthermore, we describe how this model can be applied to an image categorization problem.
Ueda, Sayoko; Kumagai, Gaku; Otaki, Yusuke; Yamaguchi, Shinya; Kohshima, Shiro
2014-01-01
As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear), B-type (only the eye position is clear), and C-type (both the pupil and eye position are unclear). A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.
Lu, Tao; Zhu, Shenmin; Ma, Jun; Lin, Jinyou; Wang, Wanlin; Pan, Hui; Tian, Feng; Zhang, Wang; Zhang, Di
2015-10-01
Thermoresponsive photonic materials having hierarchical structures are created by combining a template of Morpho butterfly wings with poly(N-isopropylacrylamide) (PNIPAM) through a chemical bonding and polymerization route. These materials show temperature-induced color tunability. Through reacting with both NIPAM monomers and the amino groups of chitosan in wing scales, glutaraldehyde workes as a bridge by creating chemical bonding between the biotemplate and the PNIPAM. The corresponding reflection peaks red-shift with increase in temperature-an opposite phenomenon to previous studies, demonstrating a thermoresponsive photonic property. This unique phenomenon is caused by the refractive index change due to the volume change of PNIPAM during the temperature rising. This work sets up an efficient strategy for the fabrication of stimuli-responsive photonic materials with hierarchical structures toward extensive applications in science and technology. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Erythrodiplax ana sp. nov. (Odonata: Libellulidae) from Brazilian palm swamps.
Guillermo-Ferreira, Rhainer; Vilela, Diogo S; Del-Claro, Kleber; Bispo, Pitágoras C
2016-08-29
Erythrodiplax ana sp. nov. (male holotype, six male and three female paratypes), collected in Vereda wetlands (a unique Neotropical savanna environment) in Uberlândia (Minas Gerais) and Chapada dos Guimarães (Mato Grosso), Brazil, is described and illustrated. The new species fits in Borror's Basalis Group, and can be distinguished from other species by the combination of the following traits: blue pruinosity dorsally on thorax and third to eighth abdominal segments; sides of the thorax olive-green; face ivory or olive-green; wings hyaline with a small apical brown spot on all four wings, well defined in females; male genitalia with sclerotized erectile posterior lobe and inflatable sac-like median process. Last instar larvae were reared in the laboratory, resulting in the description of the larva. We also followed this population for 13 months and present resulting biological notes and comments on ontogenetic color change in males, as well as longevity.
2007-08-14
Boeing Phantom Works' subscale Blended Wing Body technology demonstration aircraft began its initial flight tests from NASA's Dryden Flight Research Center at Edwards Air Force Base, Calif. in the summer of 2007. The 8.5 percent dynamically scaled unmanned aircraft, designated the X-48B by the Air Force, is designed to mimic the aerodynamic characteristics of a full-scale large cargo transport aircraft with the same blended wing body shape. The initial flight tests focused on evaluation of the X-48B's low-speed flight characteristics and handling qualities. About 25 flights were planned to gather data in these low-speed flight regimes. Based on the results of the initial flight test series, a second set of flight tests was planned to test the aircraft's low-noise and handling characteristics at transonic speeds.
A Wingless and Notch double-repression mechanism regulates G1–S transition in the Drosophila wing
Herranz, Héctor; Pérez, Lidia; Martín, Francisco A; Milán, Marco
2008-01-01
The control of tissue growth and patterning is orchestrated in various multicellular tissues by the coordinated activity of the signalling molecules Wnt/Wingless (Wg) and Notch, and mutations in these pathways can cause cancer. The role of these molecules in the control of cell proliferation and the crosstalk between their corresponding pathways remain poorly understood. Crosstalk between Notch and Wg has been proposed to organize pattern and growth in the Drosophila wing primordium. Here we report that Wg and Notch act in a surprisingly linear pathway to control G1–S progression. We present evidence that these molecules exert their function by regulating the expression of the dmyc proto-oncogene and the bantam micro-RNA, which positively modulated the activity of the E2F transcription factor. Our results demonstrate that Notch acts in this cellular context as a repressor of cell-cycle progression and Wg has a permissive role in alleviating Notch-mediated repression of G1–S progression in wing cells. PMID:18451803
Environmental heterogeneity, dispersal mode, and co-occurrence in stream macroinvertebrates
Heino, Jani
2013-01-01
Both environmental heterogeneity and mode of dispersal may affect species co-occurrence in metacommunities. Aquatic invertebrates were sampled in 20–30 streams in each of three drainage basins, differing considerably in environmental heterogeneity. Each drainage basin was further divided into two equally sized sets of sites, again differing profoundly in environmental heterogeneity. Benthic invertebrate data were divided into three groups of taxa based on overland dispersal modes: passive dispersers with aquatic adults, passive dispersers with terrestrial winged adults, and active dispersers with terrestrial winged adults. The co-occurrence of taxa in each dispersal mode group, drainage basin, and heterogeneity site subset was measured using the C-score and its standardized effect size. The probability of finding high levels of species segregation tended to increase with environmental heterogeneity across the drainage basins. These patterns were, however, contingent on both dispersal mode and drainage basin. It thus appears that environmental heterogeneity and dispersal mode interact in affecting co-occurrence in metacommunities, with passive dispersers with aquatic adults showing random patterns irrespective of environmental heterogeneity, and active dispersers with terrestrial winged adults showing increasing segregation with increasing environmental heterogeneity. PMID:23467653
The impact of circulation control on rotary aircraft controls systems
NASA Technical Reports Server (NTRS)
Kingloff, R. F.; Cooper, D. E.
1987-01-01
Application of circulation to rotary wing systems is a new development. Efforts to determine the near and far field flow patterns and to analytically predict those flow patterns have been underway for some years. Rotary wing applications present a new set of challenges in circulation control technology. Rotary wing sections must accommodate substantial Mach number, free stream dynamic pressure and section angle of attack variation at each flight condition within the design envelope. They must also be capable of short term circulation blowing modulation to produce control moments and vibration alleviation in addition to a lift augmentation function. Control system design must provide this primary control moment, vibration alleviation and lift augmentation function. To accomplish this, one must simultaneously control the compressed air source and its distribution. The control law algorithm must therefore address the compressor as the air source, the plenum as the air pressure storage and the pneumatic flow gates or valves that distribute and meter the stored pressure to the rotating blades. Also, mechanical collective blade pitch, rotor shaft angle of attack and engine power control must be maintained.
Saison, Tamar; Peroz, Christophe; Chauveau, Vanessa; Berthier, Serge; Sondergard, Elin; Arribart, Hervé
2008-12-01
An original and low cost method for the fabrication of patterned surfaces bioinspired from butterfly wings and lotus leaves is presented. Silica-based sol-gel films are thermally imprinted from elastomeric molds to produce stable structures with superhydrophobicity values as high as 160 degrees water contact angle. The biomimetic surfaces are demonstrated to be tuned from superhydrophobic to superhydrophilic by annealing between 200 degrees C and 500 degrees C.
Customized color patterning of photovoltaic cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cruz-Campa, Jose Luis; Nielson, Gregory N.; Okandan, Murat
Photovoltaic cells and photovoltaic modules, as well as methods of making and using such photovoltaic cells and photovoltaic modules, are disclosed. More particularly, embodiments of the photovoltaic cells selectively reflect visible light to provide the photovoltaic cells with a colorized appearance. Photovoltaic modules combining colorized photovoltaic cells may be used to harvest solar energy while providing a customized appearance, e.g., an image or pattern.
ERIC Educational Resources Information Center
Marschalek, Douglas G.
1988-01-01
Describes study of children in grades one, three, and five that examined their active processing and short term memory (STM) of color, contour, and interior pattern of shapes found in computer digitized pictures. Age-related differences are examined, and the role of processing visual information in the learning process is discussed. (12…
Clinical application of qualitative assessment for breast masses in shear-wave elastography.
Gweon, Hye Mi; Youk, Ji Hyun; Son, Eun Ju; Kim, Jeong-Ah
2013-11-01
To evaluate the interobserver agreement and the diagnostic performance of various qualitative features in shear-wave elastography (SWE) for breast masses. A total of 153 breast lesions in 152 women who underwent B-mode ultrasound and SWE before biopsy were included. Qualitative analysis in SWE was performed using two different classifications: E values (Ecol; 6-point color score, Ehomo; homogeneity score and Esha; shape score) and a four-color pattern classification. Two radiologists reviewed five data sets: B-mode ultrasound, SWE, and combination of both for E values and four-color pattern. The BI-RADS categories were assessed B-mode and combined sets. Interobserver agreement was assessed using weighted κ statistics. Areas under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed. Interobserver agreement was substantial for Ecol (κ=0.79), Ehomo (κ=0.77) and four-color pattern (κ=0.64), and moderate for Esha (κ=0.56). Better-performing qualitative features were Ecol and four-color pattern (AUCs, 0.932 and 0.925) compared with Ehomo and Esha (AUCs, 0.857 and 0.864; P<0.05). The diagnostic performance of B-mode ultrasound (AUC, 0.950) was not significantly different from combined sets with E value and with four color pattern (AUCs, 0.962 and 0.954). When all qualitative values were negative, leading to downgrade the BI-RADS category, the specificity increased significantly from 16.5% to 56.1% (E value) and 57.0% (four-color pattern) (P<0.001) without improvement in sensitivity. The qualitative SWE features were highly reproducible and showed good diagnostic performance in suspicious breast masses. Adding qualitative SWE to B-mode ultrasound increased specificity in decision making for biopsy recommendation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Detecting spatial defects in colored patterns using self-oscillating gels
NASA Astrophysics Data System (ADS)
Fang, Yan; Yashin, Victor V.; Dickerson, Samuel J.; Balazs, Anna C.
2018-06-01
With the growing demand for wearable computers, there is a need for material systems that can perform computational tasks without relying on external electrical power. Using theory and simulation, we design a material system that "computes" by integrating the inherent behavior of self-oscillating gels undergoing the Belousov-Zhabotinsky (BZ) reaction and piezoelectric (PZ) plates. These "BZ-PZ" units are connected electrically to form a coupled oscillator network, which displays specific modes of synchronization. We exploit this attribute in employing multiple BZ-PZ networks to perform pattern matching on complex multi-dimensional data, such as colored images. By decomposing a colored image into sets of binary vectors, we use each BZ-PZ network, or "channel," to store distinct information about the color and the shape of the image and perform the pattern matching operation. Our simulation results indicate that the multi-channel BZ-PZ device can detect subtle differences between the input and stored patterns, such as the color variation of one pixel or a small change in the shape of an object. To demonstrate a practical application, we utilize our system to process a colored Quick Response code and show its potential in cryptography and steganography.
Instrumental color control in textile printing
NASA Astrophysics Data System (ADS)
Connelly, Roland L., Sr.
1996-03-01
In textile printing there are several color outputs that need to be controlled. Just as important is the color coordination of these outputs. The types of color output are the video display on the textile design system (CATD for Computer Aided Textile Design), the color scanner, the color pattern printer, and the actual pattern printed on the textile substrate. Each of these systems has its own gamut(s) that is partially overlapping of the others and will require mapping and/or truncation to adequately represent the colors of the final print in the other systems. One of the goals of instrumentation systems is to control these devices so that the message of the pattern is the same on all four media. To accomplish this is a significant task that has yet to be completed to meet the rigorous requirements of the textile and apparel industries. Several of the major problems and directions for solving them will be discussed in this paper. These include getting good instrumental measurements, translation of data between systems, and specific problems related to the hard copy output.
Prunier, Jérôme G.; Dewulf, Alexandre; Kuhlmann, Michael; Michez, Denis
2017-01-01
Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size) variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal/structure within the intra-specific wing shape and body size variability. PMID:28273178
NASA Astrophysics Data System (ADS)
Yang, S. W.; Ma, J. J.; Wang, J. M.
2018-04-01
As representative vulnerable regions of the city, dense distribution areas of temporary color steel building are a major target for control of fire risks, illegal buildings, environmental supervision, urbanization quality and enhancement for city's image. In the domestic and foreign literature, the related research mainly focuses on fire risks and violation monitoring. However, due to temporary color steel building's special characteristics, the corresponding research about temporal and spatial distribution, and influence on urban spatial form etc. has not been reported. Therefore, firstly, the paper research aim plans to extract information of large-scale color steel building from high-resolution images. Secondly, the color steel plate buildings were classified, and the spatial and temporal distribution and aggregation characteristics of small (temporary buildings) and large (factory building, warehouse, etc.) buildings were studied respectively. Thirdly, the coupling relationship between the spatial distribution of color steel plate and the spatial pattern of urban space was analysed. The results show that there is a good coupling relationship between the color steel plate building and the urban spatial form. Different types of color steel plate building represent the pattern of regional differentiation of urban space and the phased pattern of urban development.
Spatio-spectral color filter array design for optimal image recovery.
Hirakawa, Keigo; Wolfe, Patrick J
2008-10-01
In digital imaging applications, data are typically obtained via a spatial subsampling procedure implemented as a color filter array-a physical construction whereby only a single color value is measured at each pixel location. Owing to the growing ubiquity of color imaging and display devices, much recent work has focused on the implications of such arrays for subsequent digital processing, including in particular the canonical demosaicking task of reconstructing a full color image from spatially subsampled and incomplete color data acquired under a particular choice of array pattern. In contrast to the majority of the demosaicking literature, we consider here the problem of color filter array design and its implications for spatial reconstruction quality. We pose this problem formally as one of simultaneously maximizing the spectral radii of luminance and chrominance channels subject to perfect reconstruction, and-after proving sub-optimality of a wide class of existing array patterns-provide a constructive method for its solution that yields robust, new panchromatic designs implementable as subtractive colors. Empirical evaluations on multiple color image test sets support our theoretical results, and indicate the potential of these patterns to increase spatial resolution for fixed sensor size, and to contribute to improved reconstruction fidelity as well as significantly reduced hardware complexity.
Bar, Ido; Kaddar, Ethan; Velan, Ariel; David, Lior
2013-01-01
Colors and their patterns are fascinating phenotypes with great importance for fitness under natural conditions. For this reason and because pigmentation is associated with diseases, much research was devoted to study the genetics of pigmentation in animals. Considerable contribution to our understanding of color phenotypes was made by studies in domesticated animals that exhibit dazzling variation in color traits. Koi strains, the ornamental variants of the common carp, are a striking example for color variability that was selected by man during a very short period on an evolutionary timescale. Among several pigmentation genes, genetic variation in Melanocrtin receptor 1 was repeatedly associated with dark pigmentation phenotypes in numerous animals. In this study, we cloned Melanocrtin receptor 1 from the common carp. We found that alleles of the gene were not associated with the development of black color in Koi. However, the mRNA expression levels of the gene were higher during dark pigmentation development in larvae and in dark pigmented tissues of adult fish, suggesting that variation in the regulation of the gene is associated with black color in Koi. These regulatory differences are reflected in both the timing of the dark-pigmentation development and the different mode of inheritance of the two black patterns associated with them. Identifying the genetic basis of color and color patterns in Koi will promote the production of this valuable ornamental fish. Furthermore, given the rich variety of colors and patterns, Koi serves as a good model to unravel pigmentation genes and their phenotypic effects and by that to improve our understanding of the genetic basis of colors also in natural populations.
Bar, Ido; Kaddar, Ethan; Velan, Ariel; David, Lior
2013-01-01
Colors and their patterns are fascinating phenotypes with great importance for fitness under natural conditions. For this reason and because pigmentation is associated with diseases, much research was devoted to study the genetics of pigmentation in animals. Considerable contribution to our understanding of color phenotypes was made by studies in domesticated animals that exhibit dazzling variation in color traits. Koi strains, the ornamental variants of the common carp, are a striking example for color variability that was selected by man during a very short period on an evolutionary timescale. Among several pigmentation genes, genetic variation in Melanocrtin receptor 1 was repeatedly associated with dark pigmentation phenotypes in numerous animals. In this study, we cloned Melanocrtin receptor 1 from the common carp. We found that alleles of the gene were not associated with the development of black color in Koi. However, the mRNA expression levels of the gene were higher during dark pigmentation development in larvae and in dark pigmented tissues of adult fish, suggesting that variation in the regulation of the gene is associated with black color in Koi. These regulatory differences are reflected in both the timing of the dark-pigmentation development and the different mode of inheritance of the two black patterns associated with them. Identifying the genetic basis of color and color patterns in Koi will promote the production of this valuable ornamental fish. Furthermore, given the rich variety of colors and patterns, Koi serves as a good model to unravel pigmentation genes and their phenotypic effects and by that to improve our understanding of the genetic basis of colors also in natural populations. PMID:23355846
2000-01-20
KENNEDY SPACE CENTER, FLA. -- A female roseate spoonbill displays her colorful wings in a mating ritual in Merritt Island National Wildlife Refuge. The birds, named for their brilliant pink color and paddle-shaped bill, feed in shallow water by swinging their bill back and forth, scooping up small fish and crustaceans. They typically inhabit mangroves on the coasts of southern Florida, Louisiana and Texas. The 92,000-acre refuge, which shares a boundary with Kennedy Space Center, is a habitat for more than 330 species of birds, 31 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds
2000-01-20
KENNEDY SPACE CENTER, FLA. -- A female roseate spoonbill displays her colorful wings in a mating ritual in Merritt Island National Wildlife Refuge. The birds, named for their brilliant pink color and paddle-shaped bill, feed in shallow water by swinging their bill back and forth, scooping up small fish and crustaceans. They typically inhabit mangroves on the coasts of southern Florida, Louisiana and Texas. The 92,000-acre refuge, which shares a boundary with Kennedy Space Center, is a habitat for more than 330 species of birds, 31 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds
Tong, Hui; Hong, Yuning; Dong, Yongqiang; Ren, Yan; Häussler, Matthias; Lam, Jacky W Y; Wong, Kam Sing; Tang, Ben Zhong
2007-03-01
A chiral pyran derivative containing two cholesteryl groups (1) is synthesized, and its optical properties are investigated. Whereas the isolated molecule of 1 is virtually nonluminescent in dilute solutions, it becomes highly emissive with a 2 orders of magnitude increase in fluorescence quantum yield upon aggregation in poor solvents or in solid state, showing a novel phenomenon of aggregation-induced emission (AIE). The color and efficiency of the AIE of 1 can be tuned by varying the morphology of its aggregates: photoluminescence of its aggregates formed in a tetrahydrofuran/water mixture progressively red-shifts (green --> yellow --> red) with increasing water content of the mixture, with the crystalline aggregates emitting bluer lights in higher efficiencies than their amorphous counterparts.
Possible influences on color constancy by motion of color targets and by attention-controlled gaze.
Wan, Lifang; Shinomori, Keizo
2018-04-01
We investigated the influence of motion on color constancy using a chromatic stimulus presented in various conditions (static, motion, and rotation). Attention to the stimulus and background was also controlled in different gaze modes, constant fixation of the stimulus, and random viewing of the stimulus. Color constancy was examined in six young observers using a haploscopic view of a computer monitor. The target and background were illuminated in simulation by red, green, blue, and yellow, shifted from daylight (D65) by specific color differences along L - M or S - (L + M) axes on the equiluminance plane. The standard pattern (under D65) and test pattern (under the color illuminant) of a 5-deg square were presented side by side, consisting of 1.2-deg square targets with one of 12 colors at each center, surrounded by 230 background ellipses consisting of eight other colors. The central color targets in both patterns flipped between top and bottom locations at the rate of 3 deg/s in the motion condition. The results indicated an average reduction of color constancy over the 12 test colors by motion. The random viewing parameter indicated better color constancy by more attention to the background, although the difference was not significant. Color constancy of the four color illuminations was better to worse in green, red, yellow, and blue, respectively. The reduction of color constancy by motion could be explained by less contribution of the illumination estimation effect on color constancy. In the motion with constant fixation condition, the retina strongly adapted to the mean chromaticity of the background. However, motion resulted in less attention to the color of the background, causing a weaker effect of the illumination estimation. Conversely, in the static state with a random viewing condition, more attention to the background colors caused a stronger illumination estimation effect, and color constancy was improved overall.
Román, Jessica K; Walsh, Callee M; Oh, Junho; Dana, Catherine E; Hong, Sungmin; Jo, Kyoo D; Alleyne, Marianne; Miljkovic, Nenad; Cropek, Donald M
2018-03-01
Laser-ablation electrospray ionization (LAESI) imaging mass spectrometry (IMS) is an emerging bioanalytical tool for direct imaging and analysis of biological tissues. Performing ionization in an ambient environment, this technique requires little sample preparation and no additional matrix, and can be performed on natural, uneven surfaces. When combined with optical microscopy, the investigation of biological samples by LAESI allows for spatially resolved compositional analysis. We demonstrate here the applicability of LAESI-IMS for the chemical analysis of thin, desiccated biological samples, specifically Neotibicen pruinosus cicada wings. Positive-ion LAESI-IMS accurate ion-map data was acquired from several wing cells and superimposed onto optical images allowing for compositional comparisons across areas of the wing. Various putative chemical identifications were made indicating the presence of hydrocarbons, lipids/esters, amines/amides, and sulfonated/phosphorylated compounds. With the spatial resolution capability, surprising chemical distribution patterns were observed across the cicada wing, which may assist in correlating trends in surface properties with chemical distribution. Observed ions were either (1) equally dispersed across the wing, (2) more concentrated closer to the body of the insect (proximal end), or (3) more concentrated toward the tip of the wing (distal end). These findings demonstrate LAESI-IMS as a tool for the acquisition of spatially resolved chemical information from fragile, dried insect wings. This LAESI-IMS technique has important implications for the study of functional biomaterials, where understanding the correlation between chemical composition, physical structure, and biological function is critical. Graphical abstract Positive-ion laser-ablation electrospray ionization mass spectrometry coupled with optical imaging provides a powerful tool for the spatially resolved chemical analysis of cicada wings.
Wing geometry of Culex coronator (Diptera: Culicidae) from South and Southeast Brazil
2014-01-01
Background The Coronator Group encompasses Culex coronator Dyar & Knab, Culex camposi Dyar, Culex covagarciai Forattini, Culex ousqua Dyar, Culex usquatissimus Dyar, Culex usquatus Dyar and Culex yojoae Strickman. Culex coronator has the largest geographic distribution, occurring in North, Central and South America. Moreover, it is a potential vector-borne mosquito species because females have been found naturally infected with several arboviruses, i.e., Saint Louis Encephalitis Virus, Venezuelan Equine Encephalitis Virus and West Nile Virus. Considering the epidemiological importance of Cx. coronator, we investigated the wing shape diversity of Cx. coronator from South and Southeast Brazil, a method to preliminarily estimate population diversity. Methods Field-collected immature stages of seven populations from a large geographical area in Brazil were maintained in the laboratory to obtain both females and males linked with pupal and/or larval exuviae. For each individual female, 18 landmarks of left wings were marked and digitalized. After Procrustes superimposition, discriminant analysis of shape was employed to quantify wing shape variation among populations. The isometric estimator centroid size was calculated to assess the overall wing size and allometry. Results Wing shape was polymorphic among populations of Cx. coronator. However, dissimilarities among populations were higher than those observed within each population, suggesting populational differentiation in Cx. coronator. Morphological distances between populations were not correlated to geographical distances, indicating that other factors may act on wing shape and thus, determining microevolutionary patterns in Cx. coronator. Despite the population differentiation, intrapopulational wing shape variability was equivalent among all seven populations. Conclusion The wing variability found in Cx. coronator populations brings to light a new biological problem to be investigated: the population genetics of Cx. coronator. Because of differences in the male genitalia, we also transferred Cx. yojoae to the Apicinus Subgroup. PMID:24721508
Chromosomal rearrangements maintain a polymorphic supergene controlling butterfly mimicry
Joron, Mathieu; Frezal, Lise; Jones, Robert T.; Chamberlain, Nicola L.; Lee, Siu F.; Haag, Christoph R.; Whibley, Annabel; Becuwe, Michel; Baxter, Simon W.; Ferguson, Laura; Wilkinson, Paul A.; Salazar, Camilo; Davidson, Claire; Clark, Richard; Quail, Michael A.; Beasley, Helen; Glithero, Rebecca; Lloyd, Christine; Sims, Sarah; Jones, Matthew C.; Rogers, Jane; Jiggins, Chris D.; ffrench-Constant, Richard H.
2013-01-01
Supergenes are tight clusters of loci that facilitate the co-segregation of adaptive variation, providing integrated control of complex adaptive phenotypes1. Polymorphic supergenes, in which specific combinations of traits are maintained within a single population, were first described for ‘pin’ and ‘thrum’ floral types in Primula1 and Fagopyrum2, but classic examples are also found in insect mimicry3–5 and snail morphology6. Understanding the evolutionary mechanisms that generate these co-adapted gene sets, as well as the mode of limiting the production of unfit recombinant forms, remains a substantial challenge7–10. Here we show that individual wing-pattern morphs in the polymorphic mimetic butterfly Heliconius numata are associated with different genomic rearrangements at the supergene locus P. These rearrangements tighten the genetic linkage between at least two colour-pattern loci that are known to recombine in closely related species9–11, with complete suppression of recombination being observed in experimental crosses across a 400-kilobase interval containing at least 18 genes. In natural populations, notable patterns of linkage disequilibrium (LD) are observed across the entire P region. The resulting divergent haplotype clades and inversion breakpoints are found in complete association with wing-pattern morphs. Our results indicate that allelic combinations at known wing-patterning loci have become locked together in a polymorphic rearrangement at the Plocus, forming a supergene that acts as a simple switch between complex adaptive phenotypes found in sympatry. These findings highlight how genomic rearrangements can have a central role in the coexistence of adaptive phenotypes involving several genes acting in concert, by locally limiting recombination and gene flow. PMID:21841803
NASA Astrophysics Data System (ADS)
Khan, Mahasin Ali; Bera, Subir
2017-07-01
The occurrences of Pinus L. (family Pinaceae) megafossils (cones and leaf remains) have been abundantly documented from the Cenozoic sediments of eastern Asia (Japan and China), but none has been confirmed from the Indian Cenozoic till date. Here, we describe Pinus arunachalensis Khan and Bera, sp. nov. on the basis of seed remains from the middle to late Miocene Siwalik sediments of the Dafla Formation exposed around West Kameng district in Arunachal Pradesh, eastern Himalaya. Seeds are winged, broadly oblong to oval in outline, 1.3-1.5 cm long and 0.4-0.6 cm broad (in the middle part), located basipetally and symmetrically to wing, cellular pattern of wing is seemingly undulatory and parallel with the long axis of the wing. So far, this report provides the first ever fossil record of Pinus winged seeds from India. This record suggests that Pinus was an important component of tropical-subtropical evergreen forest in the area during the Miocene and this group subsequently declined from the local vegetation probably because of the gradual intensification of MSI (monsoon index) from the Miocene to the present. We also review the historical phytogeography and highlight the phytogeographic implication of this genus.
Bédard, Emilie; Lévesque, Simon; Martin, Philippe; Pinsonneault, Linda; Paranjape, Kiran; Lalancette, Cindy; Dolcé, Charles-Éric; Villion, Manuela; Valiquette, Louis; Faucher, Sébastien P; Prévost, Michèle
2016-12-01
OBJECTIVE To determine the source of a Legionella pneumophila serogroup 5 nosocomial outbreak and the role of the heat exchanger installed on the hot water system within the previous year. SETTING A 400-bed tertiary care university hospital in Sherbrooke, Canada. METHODS Hot water samples were collected and cultured for L. pneumophila from 25 taps (baths and sinks) within wing A and 9 taps in wing B. Biofilm (5) and 2 L water samples (3) were collected within the heat exchangers for L. pneumophila culture and detection of protists. Sequence-based typing was performed on strain DNA extracts and pulsed-field gel electrophoresis patterns were analyzed. RESULTS Following 2 cases of hospital-acquired legionellosis, the hot water system investigation revealed a large proportion of L. pneumophila serogroup 5 positive taps (22/25 in wing A and 5/9 in wing B). High positivity was also detected in the heat exchanger of wing A in water samples (3/3) and swabs from the heat exchanger (4/5). The outbreak genotyping investigation identified the hot water system as the source of infections. Genotyping results revealed that all isolated environmental strains harbored the same related pulsed-field gel electrophoresis pattern and sequence-based type. CONCLUSIONS Two cases of hospital-acquired legionellosis occurred in the year following the installation of a heat exchanger to preheat hospital hot water. No cases were reported previously, although the same L. pneumophila strain was isolated from the hot water system in 1995. The heat exchanger promoted L. pneumophila growth and may have contributed to confirmed clinical cases. Infect. Control Hosp. Epidemiol. 2016;1475-1480.
Ultraviolet laser beam monitor using radiation responsive crystals
McCann, Michael P.; Chen, Chung H.
1988-01-01
An apparatus and method for monitoring an ultraviolet laser beam includes disposing in the path of an ultraviolet laser beam a substantially transparent crystal that will produce a color pattern in response to ultraviolet radiation. The crystal is exposed to the ultraviolet laser beam and a color pattern is produced within the crystal corresponding to the laser beam intensity distribution therein. The crystal is then exposed to visible light, and the color pattern is observed by means of the visible light to determine the characteristics of the laser beam that passed through crystal. In this manner, a perpendicular cross sectional intensity profile and a longitudinal intensity profile of the ultraviolet laser beam may be determined. The observation of the color pattern may be made with forward or back scattered light and may be made with the naked eye or with optical systems such as microscopes and television cameras.
NASA Astrophysics Data System (ADS)
Miyahara, Tomoko; Koda, Ai; Sekiguchi, Rikuko; Amemiya, Toshihiko
In this study, we investigated the nature of cross-modal associations between colors and vowels. In Experiment 1, we examined the patterns of synesthetic correspondence between colors and vowels in a perceptual similarity experiment. The results were as follows: red was chosen for /a/, yellow was chosen for /i/, and blue was chosen for /o/ significantly more than any other vowels. Interestingly this pattern of correspondence is similar to the pattern of colored hearing reported by synesthetes. In Experiment 2, we investigated the robustness of these cross-modal associations using an implicit association test (IAT). A clear congruence effect was found. Participants responded faster in congruent conditions (/i/ and yellow, /o/ and blue) than in incongruent conditions (/i/ and blue, /o/ and yellow). This result suggests that the weak synesthesia between vowels and colors in non-synesthtes is not the fact of mere conscious choice, but reflects some underlying implicit associations.
Flow structures around a flapping wing considering ground effect
NASA Astrophysics Data System (ADS)
Van Truong, Tien; Kim, Jihoon; Kim, Min Jun; Park, Hoon Cheol; Yoon, Kwang Joon; Byun, Doyoung
2013-07-01
Over the past several decades, there has been great interest in understanding the aerodynamics of flapping flight, namely the two flight modes of hovering and forward flight. However, there has been little focus on the aerodynamic characteristics during takeoff of insects. In a previous study we found that the Rhinoceros Beetle ( Trypoxylusdichotomus) takes off without jumping, which is uncommon for other insects. In this study we built a scaled-up electromechanical model of a flapping wing and investigated fluid flow around the beetle's wing model. In particular, the present dynamically scaled mechanical model has the wing kinematics pattern achieved from the real beetle's wing kinematics during takeoff. In addition, we could systematically change the three-dimensional inclined motion of the flapping model through each stroke. We used digital particle image velocimetry with high spatial resolution, and were able to qualitatively and quantitatively study the flow field around the wing at a Reynolds number of approximately 10,000. The present results provide insight into the aerodynamics and the evolution of vortical structures, as well as the ground effect experienced by a beetle's wing during takeoff. The main unsteady mechanisms of beetles have been identified and intensively analyzed as the stability of the leading edge vortex (LEV) during strokes, the delayed stall during upstroke, the rotational circulation in pronation periods, and wake capture in supination periods. Due to the ground effect, the LEV was enhanced during half downstroke, and the lift force could thus be increased to lift the beetle during takeoff. This is useful for researchers in developing a micro air vehicle that has a beetle-like flapping wing motion.
Simons, Erin L R; O'connor, Patrick M
2012-03-01
Wing bone histology in three species of birds was characterized in order to test hypotheses related to the relationship between skeletal microstructure and inferred wing loading during flight. Data on the degree of laminarity (the proportion of circular vascular canals) and the occurrence of secondary osteons were obtained from three species that utilize different primary flight modes: the Double-crested cormorant, a continuous flapper; the Brown pelican, a static soarer; and the Laysan albatross, a dynamic soarer. Laminarity indices were calculated for four quadrants for each of the three main wing elements. Ulnae and carpometacarpi were predicted to exhibit quadrant specific patterns of laminarity due to hypothesized differences in locally applied loads related to the attachment of flight feathers. However, few differences among the quadrants were identified. No significant differences were identified among the three elements, which is notable as different bones are likely experiencing different loading conditions. These results do not support the concept of bone functional adaptation in the primary structure of the wing elements. Significant differences in laminarity were found among the three primary flight modes. The dynamic soaring birds exhibited significantly lower laminarity than the flapping and static soaring birds. These results support the proposed hypothesis that laminarity is an adaptation for resisting torsional loading. This may be explained by overall wing shape: whereas dynamic soaring birds have long slender wings, flappers and static soaring birds have broader wings with a larger wing chord that would necessarily impart a higher torsional moment on the feather-bearing bones. Copyright © 2012 Wiley Periodicals, Inc.
Vortex Flap Technology: a Stability and Control Assessment
NASA Technical Reports Server (NTRS)
Carey, K. M.; Erickson, G. E.
1984-01-01
A comprehensive low-speed wind tunnel investigation was performed of leading edge vortex flaps applied to representative aircraft configurations. A determination was made of the effects of analytically- and empirically-designed vortex flaps on the static longitudinal and lateral-directional aerodynamics, stability, and control characteristics of fighter wings having leading-edge sweep angles of 45 to 76.5 degrees. The sensitivity to several configuration modifications was assessed, which included the effects of flap planform, leading- and trailing-edge flap deflection angles, wing location on the fuselage, forebody strakes, canards, and centerline and outboard vertical tails. Six-component forces and moments, wing surface static pressure distributions, and surface flow patterns were obtained using the Northrop 21- by 30-inch low-speed wind tunnel.
NASA Astrophysics Data System (ADS)
Faber, Jakob A.; Arrieta, Andres F.; Studart, André R.
2018-03-01
Origami enables folding of objects into a variety of shapes in arts, engineering, and biological systems. In contrast to well-known paper-folded objects, the wing of the earwig has an exquisite natural folding system that cannot be sufficiently described by current origami models. Such an unusual biological system displays incompatible folding patterns, remains open by a bistable locking mechanism during flight, and self-folds rapidly without muscular actuation. We show that these notable functionalities arise from the protein-rich joints of the earwig wing, which work as extensional and rotational springs between facets. Inspired by this biological wing, we establish a spring origami model that broadens the folding design space of traditional origami and allows for the fabrication of precisely tunable, four-dimensional–printed objects with programmable bioinspired morphing functionalities.
McCulloch, Kyle J; Osorio, Daniel; Briscoe, Adriana D
2016-08-01
Most butterfly families expand the number of spectrally distinct photoreceptors in their compound eye by opsin gene duplications together with lateral filter pigments; however, most nymphalid genera have limited diversity, with only three or four spectral types of photoreceptor. Here, we examined the spatial pattern of opsin expression and photoreceptor spectral sensitivities in Heliconius erato, a nymphalid with duplicate ultraviolet opsin genes, UVRh1 and UVRh2 We found that the H. erato compound eye is sexually dimorphic. Females express the two UV opsin proteins in separate photoreceptors, but males do not express UVRh1. Intracellular recordings confirmed that females have three short wavelength-sensitive photoreceptors (λmax=356, ∼390 and 470 nm), while males have two (λmax=390 and ∼470 nm). We also found two long wavelength-sensitive photoreceptors (green, λmax∼555 nm, and red, λmax∼600 nm), which express the same LW opsin. The red cell's shifted sensitivity is probably due to perirhabdomal filtering pigments. Sexual dimorphism of the UV-absorbing rhodopsins may reflect the females' need to discriminate conspecifics from co-mimics. Red-green color vision may be used to detect differences in red coloration on Heliconius wings, or for host-plant identification. Among nymphalids so far investigated, only H. erato is known to possess five spectral classes of photoreceptor; sexual dimorphism of the eye via suppression of one class of opsin (here UVRh1 in males) has not - to our knowledge - been reported in any animal. © 2016. Published by The Company of Biologists Ltd.
Proprioceptive input patterns elevator activity in the locust flight system.
Wolf, H; Pearson, K G
1988-06-01
1. In the locust, Locusta migratoria, the roles of two groups of wing sense organs, hind wing tegulae and wing-hinge stretch receptors, in the generation of the flight motor pattern were investigated. A preparation was employed that allowed the intracellular recording of neural activity in almost intact tethered flying locusts or after selective manipulations of sensory input. The functions of the two sets of receptors were assessed 1) by studying the phases of their discharges in the wingbeat cycle (Fig. 3), 2) by the selective ablation of input from the receptors (Figs. 4-7), and 3) by the selective stimulation of the receptor afferents (Figs. 8-12). 2. Input from the tegulae was found to be responsible for the initiation of elevator activity (Figs. 9 and 10) and for the generation of a distinct initial rapid depolarization (Figs. 4, 5, and 8) characteristic of elevator motor neuron activity in intact locusts (Figs. 1 and 16). 3. Input from the wing-hinge stretch receptors was found to control the duration of elevator depolarizations by the graded suppression of a second late component of the elevator depolarizations as wingbeat frequency increased (Figs. 6, 7, 11, and 12). The characteristics of this late component of elevator activity suggested that it is generated by the same (central nervous) mechanism that produces the elevator depolarizations recorded in deafferented animals (Fig. 2). Apparently this late component contributes to the intact pattern of elevator depolarizations only at lower wingbeat frequencies and is abolished by the action of stretch-receptor input at frequencies above approximately 15 Hz (Figs. 1, 2, and 4). At these high wingbeat frequencies elevator activity is dominated by the rapid depolarizations generated as a result of tegula input. 4. The present study demonstrates 1) that the timing of elevator motor neuron activity is determined by phasic afferent input from tegulae and stretch receptors and 2) that input from the stretch receptors controls the duration of elevator activity in the wingbeat cycle following the wing movement that was responsible for the generation of the receptor discharge.
Ueda, Sayoko; Kumagai, Gaku; Otaki, Yusuke; Yamaguchi, Shinya; Kohshima, Shiro
2014-01-01
As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear), B-type (only the eye position is clear), and C-type (both the pupil and eye position are unclear). A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication. PMID:24918751
Automatic identification of bird targets with radar via patterns produced by wing flapping.
Zaugg, Serge; Saporta, Gilbert; van Loon, Emiel; Schmaljohann, Heiko; Liechti, Felix
2008-09-06
Bird identification with radar is important for bird migration research, environmental impact assessments (e.g. wind farms), aircraft security and radar meteorology. In a study on bird migration, radar signals from birds, insects and ground clutter were recorded. Signals from birds show a typical pattern due to wing flapping. The data were labelled by experts into the four classes BIRD, INSECT, CLUTTER and UFO (unidentifiable signals). We present a classification algorithm aimed at automatic recognition of bird targets. Variables related to signal intensity and wing flapping pattern were extracted (via continuous wavelet transform). We used support vector classifiers to build predictive models. We estimated classification performance via cross validation on four datasets. When data from the same dataset were used for training and testing the classifier, the classification performance was extremely to moderately high. When data from one dataset were used for training and the three remaining datasets were used as test sets, the performance was lower but still extremely to moderately high. This shows that the method generalizes well across different locations or times. Our method provides a substantial gain of time when birds must be identified in large collections of radar signals and it represents the first substantial step in developing a real time bird identification radar system. We provide some guidelines and ideas for future research.
Ectopic KNOX Expression Affects Plant Development by Altering Tissue Cell Polarity and Identity[OPEN
Rebocho, Alexandra B.
2016-01-01
Plant development involves two polarity types: tissue cell (asymmetries within cells are coordinated across tissues) and regional (identities vary spatially across tissues) polarity. Both appear altered in the barley (Hordeum vulgare) Hooded mutant, in which ectopic expression of the KNOTTED1-like Homeobox (KNOX) gene, BKn3, causes inverted polarity of differentiated hairs and ectopic flowers, in addition to wing-shaped outgrowths. These lemma-specific effects allow the spatiotemporal analysis of events following ectopic BKn3 expression, determining the relationship between KNOXs, polarity, and shape. We show that tissue cell polarity, based on localization of the auxin transporter SISTER OF PINFORMED1 (SoPIN1), dynamically reorients as ectopic BKn3 expression increases. Concurrently, ectopic expression of the auxin importer LIKE AUX1 and boundary gene NO APICAL MERISTEM is activated. The polarity of hairs reflects SoPIN1 patterns, suggesting that tissue cell polarity underpins oriented cell differentiation. Wing cell files reveal an anisotropic growth pattern, and computational modeling shows how polarity guiding growth can account for this pattern and wing emergence. The inverted ectopic flower orientation does not correlate with SoPIN1, suggesting that this form of regional polarity is not controlled by tissue cell polarity. Overall, the results suggest that KNOXs trigger different morphogenetic effects through interplay between tissue cell polarity, identity, and growth. PMID:27553356
Cruising the rain forest floor: butterfly wing shape evolution and gliding in ground effect.
Cespedes, Ann; Penz, Carla M; DeVries, Philip J
2015-05-01
Flight is a key innovation in the evolutionary success of insects and essential to dispersal, territoriality, courtship and oviposition. Wing shape influences flight performance and selection likely acts to maximize performance for conducting essential behaviours that in turn results in the evolution of wing shape. As wing shape also contributes to fitness, optimal shapes for particular flight behaviours can be assessed with aerodynamic predictions and placed in an ecomorphological context. Butterflies in the tribe Haeterini (Nymphalidae) are conspicuous members of understorey faunas in lowland Neotropical forests. Field observations indicate that the five genera in this clade differ in flight height and behaviour: four use gliding flight at the forest floor level, and one utilizes flapping flight above the forest floor. Nonetheless, the association of ground level gliding flight behaviour and wing shape has never been investigated in this or any other butterfly group. We used landmark-based geometric morphometrics to test whether wing shapes in Haeterini and their close relatives reflected observed flight behaviours. Four genera of Haeterini and some distantly related Satyrinae showed significant correspondence between wing shape and theoretical expectations in performance trade-offs that we attribute to selection for gliding in ground effect. Forewing shape differed between sexes for all taxa, and male wing shapes were aerodynamically more efficient for gliding flight than corresponding females. This suggests selection acts differentially on male and female wing shapes, reinforcing the idea that sex-specific flight behaviours contribute to the evolution of sexual dimorphism. Our study indicates that wing shapes in Haeterini butterflies evolved in response to habitat-specific flight behaviours, namely gliding in ground effect along the forest floor, resulting in ecomorphological partitions of taxa in morphospace. The convergent flight behaviour and wing morphology between tribes of Satyrinae suggest that the flight environment may offset phylogenetic constraints. Overall, this study provides a basis for exploring similar patterns of wing shape evolution in other taxa that glide in ground effect. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.
Global control of colored moiré pattern in layered optical structures
NASA Astrophysics Data System (ADS)
Li, Kunyang; Zhou, Yangui; Pan, Di; Ma, Xueyan; Ma, Hongqin; Liang, Haowen; Zhou, Jianying
2018-05-01
Accurate description of visual effect of colored moiré pattern caused by layered optical structures consisting of gratings and Fresnel lens is proposed in this work. The colored moiré arising from the periodic and quasi-periodic structures is numerically simulated and experimentally verified. It is found that the visibility of moiré pattern generated by refractive optical elements is related to not only the spatial structures of gratings but also the viewing angles. To effectively control the moiré visibility, two constituting gratings are slightly separated. Such scheme is proved to be effective to globally eliminate moiré pattern for displays containing refractive optical films with quasi-periodic structures.
ASTRONAUT KERWIN, JOSEPH P. - EXTRAVEHICULAR ACTIVITY (EVA) - SKYLAB (SL)-2
1973-06-01
S73-27562 (June 1973) --- Scientist-astronaut Joseph P. Kerwin, Skylab 2 science pilot, performs extravehicular activity (EVA) at the Skylab 1 and 2 space station cluster in Earth orbit, as seen in this reproduction taken from a color television transmission made by a TV camera aboard the station. Kerwin is just outside the Airlock Module. Kerwin assisted astronaut Charles Conrad Jr., Skylab 2 commander, during the successful EVA attempt to free the stuck solar array system wing on the Orbital Workshop. Photo credit: NASA
Population genomics of parallel hybrid zones in the mimetic butterflies, H. melpomene and H. erato
Ruiz, Mayté; Salazar, Patricio; Counterman, Brian; Medina, Jose Alejandro; Ortiz-Zuazaga, Humberto; Morrison, Anna; Papa, Riccardo
2014-01-01
Hybrid zones can be valuable tools for studying evolution and identifying genomic regions responsible for adaptive divergence and underlying phenotypic variation. Hybrid zones between subspecies of Heliconius butterflies can be very narrow and are maintained by strong selection acting on color pattern. The comimetic species, H. erato and H. melpomene, have parallel hybrid zones in which both species undergo a change from one color pattern form to another. We use restriction-associated DNA sequencing to obtain several thousand genome-wide sequence markers and use these to analyze patterns of population divergence across two pairs of parallel hybrid zones in Peru and Ecuador. We compare two approaches for analysis of this type of data—alignment to a reference genome and de novo assembly—and find that alignment gives the best results for species both closely (H. melpomene) and distantly (H. erato, ∼15% divergent) related to the reference sequence. Our results confirm that the color pattern controlling loci account for the majority of divergent regions across the genome, but we also detect other divergent regions apparently unlinked to color pattern differences. We also use association mapping to identify previously unmapped color pattern loci, in particular the Ro locus. Finally, we identify a new cryptic population of H. timareta in Ecuador, which occurs at relatively low altitude and is mimetic with H. melpomene malleti. PMID:24823669
The Aerodynamics of Hovering Insect Flight. III. Kinematics
NASA Astrophysics Data System (ADS)
Ellington, C. P.
1984-02-01
Insects in free flight were filmed at 5000 frames per second to determine the motion of their wings and bodies. General comments are offered on flight behaviour and manoeuvrability. Changes in the tilt of the stroke plane with respect to the horizontal provides kinematic control of manoeuvres, analogous to the type of control used for helicopters. A projection analysis technique is described that solves for the orientation of the animal with respect to a camera-based coordinate system, giving full kinematic details for the longitudinal wing and body axes from single-view films. The technique can be applied to all types of flight where the wing motions are bilaterally symmetrical: forward, backward and hovering flight, as well as properly banked turns. An analysis of the errors of the technique is presented, and shows that the reconstructed angles for wing position should be accurate to within 1-2^circ in general. Although measurement of the angles of attack was not possible, visual estimations are given. Only 11 film sequences show flight velocities and accelerations that are small enough for the flight to be considered as `hovering'. Two sequences are presented for a hover-fly using an inclined stroke plane, and nine sequences of hovering with a horizontal stroke plane by another hover-fly, two crane-flies, a drone-fly, a ladybird beetle, a honey bee, and two bumble bees. In general, oscillations in the body position from its mean motion are within measurement error, about 1-2% of the wing length. The amplitudes of oscillation for the body angle are only a few degrees, but the phase relation of this oscillation to the wingbeat cycle could be determined for a few sequences. The phase indicates that the pitching moments governing the oscillations result from the wing lift at the ends of the wingbeat, and not from the wing drag or inertial forces. The mean pitching moment of the wings, which determines the mean body angle, is controlled by shifting the centre of lift over the cycle by changing the mean positional angle of the flapping wings. Deviations of the wing tip path from the stroke plane are never large, and no consistent pattern could be found for the wing paths of different insects; indeed, variations in the path were even observed for individual insects. The wing motion is not greatly different from simple harmonic motion, but does show a general trend towards higher accelerations and decelerations at either end of the wingbeat, with constant velocities during the middle of half-strokes. Root mean square and cube root mean cube angular velocities are on average about 4 and 9% lower than simple harmonic motion. Angles of attack are nearly constant during the middle of half-strokes, typically 35^circ at a position 70% along the wing length. The wing is twisted along its length, with angles of attack at the wing base some 10-20^circ greater than at the tip. The wings rotate through about 110^circ at either end of the wingbeat during 10-20% of the cycle period. The mean velocity of the wing edges during rotation is similar to the mean flapping velocity of the wing tip and greater than the flapping velocity for more proximal wing regions, which indicates that vortex shedding during rotation is comparable with that during flapping. The wings tend to rotate as a flat plate during the first half of rotation, which ends just before, or at, the end of the half-stroke. The hover-fly using an inclined stroke plane provides a notable exception to this general pattern: pronation is delayed and overlaps the beginning of the downstroke. The wing profile flexes along a more or less localized longitudinal axis during the second half of rotation, generating the `flip' profile postulated by Weis-Fogh for the hover-flies. This profile occurs to some extent for all of the insects, and is not exceptionally pronounced for the hover-fly. By the end of rotation the wings are nearly flat again, although a slight camber can sometimes be seen. Weis-Fogh showed that beneficial aerodynamic interference can result when the left and right wings come into contact during rotation at the end of the wingbeat. His `fling' mechanism creates the circulation required for wing lift on the subsequent half-stroke, and can be seen on my films of the Large Cabbage White butterfly, a plume moth, and the Mediterranean flour moth. However, their wings `peel' apart like two pieces of paper being separated, rather than fling open rigidly about the trailing edges. A `partial fling' was found for some insects, with the wings touching only along posterior wing areas. A `near fling' with the wings separated by a fraction of the chord was also observed for many insects. There is a continuous spectrum for the separation distance between the wings, in fact, and the separation can vary for a given insect during different manoeuvres. It is suggested that these variants on Weis-Fogh's fling mechanism also generate circulation for wing lift, although less effectively than a complete fling, and that changes in the separation distance may provide a fine control over the amount of lift produced.
Schertel, Claus; Albarca, Monica; Rockel-Bauer, Claudia; Kelley, Nicholas W.; Bischof, Johannes; Hens, Korneel
2015-01-01
Transcription factors (TFs) are key regulators of cell fate. The estimated 755 genes that encode DNA binding domain-containing proteins comprise ∼5% of all Drosophila genes. However, the majority has remained uncharacterized so far due to the lack of proper genetic tools. We generated 594 site-directed transgenic Drosophila lines that contain integrations of individual UAS-TF constructs to facilitate spatiotemporally controlled misexpression in vivo. All transgenes were expressed in the developing wing, and two-thirds induced specific phenotypic defects. In vivo knockdown of the same genes yielded a phenotype for 50%, with both methods indicating a great potential for misexpression to characterize novel functions in wing growth, patterning, and development. Thus, our UAS-TF library provides an important addition to the genetic toolbox of Drosophila research, enabling the identification of several novel wing development-related TFs. In parallel, we established the chromatin landscape of wing imaginal discs by ChIP-seq analyses of five chromatin marks and RNA Pol II. Subsequent clustering revealed six distinct chromatin states, with two clusters showing enrichment for both active and repressive marks. TFs that carry such “bivalent” chromatin are highly enriched for causing misexpression phenotypes in the wing, and analysis of existing expression data shows that these TFs tend to be differentially expressed across the wing disc. Thus, bivalently marked chromatin can be used as a marker for spatially regulated TFs that are functionally relevant in a developing tissue. PMID:25568052
Efficiency of lift production in flapping and gliding flight of swifts.
Henningsson, Per; Hedenström, Anders; Bomphrey, Richard J
2014-01-01
Many flying animals use both flapping and gliding flight as part of their routine behaviour. These two kinematic patterns impose conflicting requirements on wing design for aerodynamic efficiency and, in the absence of extreme morphing, wings cannot be optimised for both flight modes. In gliding flight, the wing experiences uniform incident flow and the optimal shape is a high aspect ratio wing with an elliptical planform. In flapping flight, on the other hand, the wing tip travels faster than the root, creating a spanwise velocity gradient. To compensate, the optimal wing shape should taper towards the tip (reducing the local chord) and/or twist from root to tip (reducing local angle of attack). We hypothesised that, if a bird is limited in its ability to morph its wings and adapt its wing shape to suit both flight modes, then a preference towards flapping flight optimization will be expected since this is the most energetically demanding flight mode. We tested this by studying a well-known flap-gliding species, the common swift, by measuring the wakes generated by two birds, one in gliding and one in flapping flight in a wind tunnel. We calculated span efficiency, the efficiency of lift production, and found that the flapping swift had consistently higher span efficiency than the gliding swift. This supports our hypothesis and suggests that even though swifts have been shown previously to increase their lift-to-drag ratio substantially when gliding, the wing morphology is tuned to be more aerodynamically efficient in generating lift during flapping. Since body drag can be assumed to be similar for both flapping and gliding, it follows that the higher total drag in flapping flight compared with gliding flight is primarily a consequence of an increase in wing profile drag due to the flapping motion, exceeding the reduction in induced drag.
Efficiency of Lift Production in Flapping and Gliding Flight of Swifts
Henningsson, Per; Hedenström, Anders; Bomphrey, Richard J.
2014-01-01
Many flying animals use both flapping and gliding flight as part of their routine behaviour. These two kinematic patterns impose conflicting requirements on wing design for aerodynamic efficiency and, in the absence of extreme morphing, wings cannot be optimised for both flight modes. In gliding flight, the wing experiences uniform incident flow and the optimal shape is a high aspect ratio wing with an elliptical planform. In flapping flight, on the other hand, the wing tip travels faster than the root, creating a spanwise velocity gradient. To compensate, the optimal wing shape should taper towards the tip (reducing the local chord) and/or twist from root to tip (reducing local angle of attack). We hypothesised that, if a bird is limited in its ability to morph its wings and adapt its wing shape to suit both flight modes, then a preference towards flapping flight optimization will be expected since this is the most energetically demanding flight mode. We tested this by studying a well-known flap-gliding species, the common swift, by measuring the wakes generated by two birds, one in gliding and one in flapping flight in a wind tunnel. We calculated span efficiency, the efficiency of lift production, and found that the flapping swift had consistently higher span efficiency than the gliding swift. This supports our hypothesis and suggests that even though swifts have been shown previously to increase their lift-to-drag ratio substantially when gliding, the wing morphology is tuned to be more aerodynamically efficient in generating lift during flapping. Since body drag can be assumed to be similar for both flapping and gliding, it follows that the higher total drag in flapping flight compared with gliding flight is primarily a consequence of an increase in wing profile drag due to the flapping motion, exceeding the reduction in induced drag. PMID:24587260
Semi-automatic mapping for identifying complex geobodies in seismic images
NASA Astrophysics Data System (ADS)
Domínguez-C, Raymundo; Romero-Salcedo, Manuel; Velasquillo-Martínez, Luis G.; Shemeretov, Leonid
2017-03-01
Seismic images are composed of positive and negative seismic wave traces with different amplitudes (Robein 2010 Seismic Imaging: A Review of the Techniques, their Principles, Merits and Limitations (Houten: EAGE)). The association of these amplitudes together with a color palette forms complex visual patterns. The color intensity of such patterns is directly related to impedance contrasts: the higher the contrast, the higher the color intensity. Generally speaking, low impedance contrasts are depicted with low tone colors, creating zones with different patterns whose features are not evident for a 3D automated mapping option available on commercial software. In this work, a workflow for a semi-automatic mapping of seismic images focused on those areas with low-intensity colored zones that may be associated with geobodies of petroleum interest is proposed. The CIE L*A*B* color space was used to perform the seismic image processing, which helped find small but significant differences between pixel tones. This process generated binary masks that bound color regions to low-intensity colors. The three-dimensional-mask projection allowed the construction of 3D structures for such zones (geobodies). The proposed method was applied to a set of digital images from a seismic cube and tested on four representative study cases. The obtained results are encouraging because interesting geobodies are obtained with a minimum of information.
Experimental Influence Coefficients and Vibration Modes
NASA Technical Reports Server (NTRS)
Weidman, Deene J.; Kordes, Eldon E.
1959-01-01
Test results are presented for both symmetrical and antisymmetrical static loading of a wing model mounted on a three-point support system. The first six free-free vibration modes were determined experimentally. A comparison is made of the symmetrical nodal patterns and frequencies with the symmetrical nodal patterns and frequencies calculated from the experimental influence coefficients.
Nonlinear dynamics of cortical responses to color in the human cVEP.
Nunez, Valerie; Shapley, Robert M; Gordon, James
2017-09-01
The main finding of this paper is that the human visual cortex responds in a very nonlinear manner to the color contrast of pure color patterns. We examined human cortical responses to color checkerboard patterns at many color contrasts, measuring the chromatic visual evoked potential (cVEP) with a dense electrode array. Cortical topography of the cVEPs showed that they were localized near the posterior electrode at position Oz, indicating that the primary cortex (V1) was the major source of responses. The choice of fine spatial patterns as stimuli caused the cVEP response to be driven by double-opponent neurons in V1. The cVEP waveform revealed nonlinear color signal processing in the V1 cortex. The cVEP time-to-peak decreased and the waveform's shape was markedly narrower with increasing cone contrast. Comparison of the linear dynamics of retinal and lateral geniculate nucleus responses with the nonlinear dynamics of the cortical cVEP indicated that the nonlinear dynamics originated in the V1 cortex. The nature of the nonlinearity is a kind of automatic gain control that adjusts cortical dynamics to be faster when color contrast is greater.
Superfast high-resolution absolute 3D recovery of a stabilized flapping flight process.
Li, Beiwen; Zhang, Song
2017-10-30
Scientific research of a stabilized flapping flight process (e.g. hovering) has been of great interest to a variety of fields including biology, aerodynamics, and bio-inspired robotics. Different from the current passive photogrammetry based methods, the digital fringe projection (DFP) technique has the capability of performing dense superfast (e.g. kHz) 3D topological reconstructions with the projection of defocused binary patterns, yet it is still a challenge to measure a flapping flight process with the presence of rapid flapping wings. This paper presents a novel absolute 3D reconstruction method for a stabilized flapping flight process. Essentially, the slow motion parts (e.g. body) and the fast-motion parts (e.g. wings) are segmented and separately reconstructed with phase shifting techniques and the Fourier transform, respectively. The topological relations between the wings and the body are utilized to ensure absolute 3D reconstruction. Experiments demonstrate the success of our computational framework by testing a flapping wing robot at different flapping speeds.
Underwater flight by the planktonic sea butterfly.
Murphy, David W; Adhikari, Deepak; Webster, Donald R; Yen, Jeannette
2016-02-01
In a remarkable example of convergent evolution, we show that the zooplanktonic sea butterfly Limacina helicina 'flies' underwater in the same way that very small insects fly in the air. Both sea butterflies and flying insects stroke their wings in a characteristic figure-of-eight pattern to produce lift, and both generate extra lift by peeling their wings apart at the beginning of the power stroke (the well-known Weis-Fogh 'clap-and-fling' mechanism). It is highly surprising to find a zooplankter 'mimicking' insect flight as almost all zooplankton swim in this intermediate Reynolds number range (Re=10-100) by using their appendages as paddles rather than wings. The sea butterfly is also unique in that it accomplishes its insect-like figure-of-eight wing stroke by extreme rotation of its body (what we call 'hyper-pitching'), a paradigm that has implications for micro aerial vehicle (MAV) design. No other animal, to our knowledge, pitches to this extent under normal locomotion. © 2016. Published by The Company of Biologists Ltd.
Dahal, Giri Raj; Pradhan, Sarala Joshi; Bates, Emily Anne
2017-08-01
Loss of embryonic ion channel function leads to morphological defects, but the underlying reason for these defects remains elusive. Here, we show that inwardly rectifying potassium (Irk) channels regulate release of the Drosophila bone morphogenetic protein Dpp in the developing fly wing and that this is necessary for developmental signaling. Inhibition of Irk channels decreases the incidence of distinct Dpp-GFP release events above baseline fluorescence while leading to a broader distribution of Dpp-GFP. Work by others in different cell types has shown that Irk channels regulate peptide release by modulating membrane potential and calcium levels. We found calcium transients in the developing wing, and inhibition of Irk channels reduces the duration and amplitude of calcium transients. Depolarization with high extracellular potassium evokes Dpp release. Taken together, our data implicate Irk channels as a requirement for regulated release of Dpp, highlighting the importance of the temporal pattern of Dpp presentation for morphogenesis of the wing. © 2017. Published by The Company of Biologists Ltd.
Okada, Hirokazu; Ebhardt, H Alexander; Vonesch, Sibylle Chantal; Aebersold, Ruedi; Hafen, Ernst
2016-09-01
The manner by which genetic diversity within a population generates individual phenotypes is a fundamental question of biology. To advance the understanding of the genotype-phenotype relationships towards the level of biochemical processes, we perform a proteome-wide association study (PWAS) of a complex quantitative phenotype. We quantify the variation of wing imaginal disc proteomes in Drosophila genetic reference panel (DGRP) lines using SWATH mass spectrometry. In spite of the very large genetic variation (1/36 bp) between the lines, proteome variability is surprisingly small, indicating strong molecular resilience of protein expression patterns. Proteins associated with adult wing size form tight co-variation clusters that are enriched in fundamental biochemical processes. Wing size correlates with some basic metabolic functions, positively with glucose metabolism but negatively with mitochondrial respiration and not with ribosome biogenesis. Our study highlights the power of PWAS to filter functional variants from the large genetic variability in natural populations.
Zhang, Ke; Tang, Yiwen; Meng, Jinsong; Wang, Ge; Zhou, Han; Fan, Tongxiang; Zhang, Di
2014-11-03
Polarization-sensitive color originates from polarization-dependent reflection or transmission, exhibiting abundant light information, including intensity, spectral distribution, and polarization. A wide range of butterflies are physiologically sensitive to polarized light, but the origins of polarized signal have not been fully understood. Here we systematically investigate the colorful scales of six species of butterfly to reveal the physical origins of polarization-sensitive color. Microscopic optical images under crossed polarizers exhibit their polarization-sensitive characteristic, and micro-structural characterizations clarify their structural commonality. In the case of the structural scales that have deep ridges, the polarization-sensitive color related with scale azimuth is remarkable. Periodic ridges lead to the anisotropic effective refractive indices in the parallel and perpendicular grating orientations, which achieves form-birefringence, resulting in the phase difference of two different component polarized lights. Simulated results show that ridge structures with reflecting elements reflect and rotate the incident p-polarized light into s-polarized light. The dimensional parameters and shapes of grating greatly affect the polarization conversion process, and the triangular deep grating extends the outstanding polarization conversion effect from the sub-wavelength period to the period comparable to visible light wavelength. The parameters of ridge structures in butterfly scales have been optimized to fulfill the polarization-dependent reflection for secret communication. The structural and physical origin of polarization conversion provides a more comprehensive perspective on the creation of polarization-sensitive color in butterfly wing scales. These findings show great potential in anti-counterfeiting technology and advanced optical material design.