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Sample records for alligators alligator mississippiensis

  1. Nonpineal melatonin in the alligator (Alligator mississippiensis).

    PubMed

    Roth, J J; Gern, W A; Roth, E C; Ralph, C L; Jacobson, E

    1980-10-31

    All living and most fossil representatives of the reptilian subclass Archosauria lack pineal bodies. Arrhythmic, low-level, nonpineal melatonin is present, however, in the blood of Alligator mississippiensis. Although pineal bodies have been implicated in circadian phenomena, these results suggest that arrhytmic melatonin in alligators may not be involved incircadian events and indicate that the pineal is not the only source of the hormone melatonin. The evolutionary loss of the pineal in Archosauria occurred during the Mesozoic, and era noted for its seasonal stability. Arrhythmic melatonin titers inalligators and pineal loss in alligators and other archosaurs may be related to Mesozoic seasonal stability. PMID:7423204

  2. OOGENESIS AND OVARIAN HISTOLOGY OF THE AMERICAN ALLIGATOR ALLIGATOR MISSISSIPPIENSIS

    EPA Science Inventory

    Although folliculogenesis and oogenesis have been observed in numerous reptiles, these phenomena have not been described in detail in a crocodilian. Oogenesis and histological features of the adult ovary of Alligator mississippiensis are described. Using a complex process, the ov...

  3. Essential fatty acid nutrition of the American alligator (Alligator mississippiensis).

    PubMed

    Staton, M A; Edwards, H M; Brisbin, I L; Joanen, T; McNease, L

    1990-07-01

    The essential fatty acid (EFA) nutrition of young American alligators (Alligator mississippiensis) was examined by feeding a variety of fats/oils with potential EFA activity. Over a 12-wk period, alligators fed diets containing 2.5 or 5.0% chicken liver oil grew longer and heavier and converted feed to body mass more efficiently than alligators fed other fat/oil combinations that lacked or contained only trace amounts of arachidonic acid [20:4(n-6)]. Alligators fed an EFA-deficient diet (containing only coconut fat as the dietary fat) were the slowest-growing animals and converted feed to body mass least efficiently. However, over a 41-wk feeding period, alligators fed this diet showed no obvious external signs of deficiency other than being reduced in size and unthrifty. Fatty acid composition of heart, liver, muscle, skin and adipose tissue lipids was influenced markedly by dietary fat composition. Tissues varied significantly in response to dietary fat composition. Heart lipids contained the lowest levels of short- and medium-chain fatty acids and the highest levels of arachidonic acid. Arachidonic acid levels were less influenced by diet than were levels of other 20- and 22-carbon polyunsaturated fatty acids. Radiotracer studies indicated that linoleic acid was converted to arachidonic acid in the liver. Nevertheless, tissue arachidonic acid levels also appeared to be maintained by concentration from dietary sources and selective conservation. It appears that a dietary source of arachidonic acid may be required for a maximum rate of growth. PMID:2114472

  4. Bioprospecting the American alligator (Alligator mississippiensis) host defense peptidome.

    PubMed

    Bishop, Barney M; Juba, Melanie L; Devine, Megan C; Barksdale, Stephanie M; Rodriguez, Carlos Alberto; Chung, Myung C; Russo, Paul S; Vliet, Kent A; Schnur, Joel M; van Hoek, Monique L

    2015-01-01

    Cationic antimicrobial peptides and their therapeutic potential have garnered growing interest because of the proliferation of bacterial resistance. However, the discovery of new antimicrobial peptides from animals has proven challenging due to the limitations associated with conventional biochemical purification and difficulties in predicting active peptides from genomic sequences, if known. As an example, no antimicrobial peptides have been identified from the American alligator, Alligator mississippiensis, although their serum is antimicrobial. We have developed a novel approach for the discovery of new antimicrobial peptides from these animals, one that capitalizes on their fundamental and conserved physico-chemical properties. This sample-agnostic process employs custom-made functionalized hydrogel microparticles to harvest cationic peptides from biological samples, followed by de novo sequencing of captured peptides, eliminating the need to isolate individual peptides. After evaluation of the peptide sequences using a combination of rational and web-based bioinformatic analyses, forty-five potential antimicrobial peptides were identified, and eight of these peptides were selected to be chemically synthesized and evaluated. The successful identification of multiple novel peptides, exhibiting antibacterial properties, from Alligator mississippiensis plasma demonstrates the potential of this innovative discovery process in identifying potential new host defense peptides. PMID:25671663

  5. Distribution of ventilation in American alligator Alligator mississippiensis

    SciTech Connect

    Bickler, P.E.; Spragg, R.G.; Hartman, M.T.; White, F.N.

    1985-10-01

    The regional distribution of ventilation in the multicameral lung of spontaneously ventilating alligators (Alligator mississippiensis) was studied with TTXe scintigraphy. Frequent gamma camera images of TTXe washin and washout were obtained and processed to allow evaluation of regional ventilation. Washin of TTXe to equilibrium occurred in three to four breaths in anterior, central, and posterior compartments. Washin was most rapid in the posterior compartment and slowest in the anterior. The structure of the lungs and distribution of ventilation of inspired gas is consistent with the rapid radial spread of gas through a parallel arrangement of lung units surrounding the central intrapulmonary bronchus. Washout to equilibrium of TTXe from all compartments occurred within three to four breaths. This rapid washin and washout of gas to all parts of the lung stands in contrast to the lungs of turtles and snakes, in which the caudal air sacs are relatively poorly ventilated.

  6. Coronary blood flow in the anesthetized American alligator (Alligator mississippiensis).

    PubMed

    Jensen, Bjarke; Elfwing, Magnus; Elsey, Ruth M; Wang, Tobias; Crossley, Dane A

    2016-01-01

    Coronary circulation of the heart evolved early within ectothermic vertebrates and became of vital importance to cardiac performance in some teleost fish, mammals and birds. In contrast, the role and function of the coronary circulation in ectothermic reptiles remains largely unknown. Here, we investigated the systemic and coronary arterial responses of five anesthetized juvenile American alligators (Alligator mississippiensis) to hypoxia, acetylcholine, adenosine, sodium nitroprusside, isoproterenol, and phenylephrine. We recorded electrocardiograms, monitored systemic blood pressure, blood flows in both aortae, and blood flow in a major coronary artery supplying most of the right ventricle. Coronary arterial blood flow was generally forward, but there was a brief retrograde flow during a ventricular contraction. Blood pressure was significantly changed in all conditions. Acetylcholine decreased coronary forward flow, but this response was confounded by the concomitant lowered work of the ventricles due to decreased heart rate and blood pressure. Coronary forward flow was poorly correlated with heart rate and mean arterial pressure across treatments. Overall changes in coronary forward flow, significant and not significant, were generally in the same direction as mean arterial pressure and ventricular power, approximated as the product of systemic cardiac output and mean arterial pressure. PMID:26436857

  7. THYROID STATUS IN JUVENILE ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED AND REFERENCE SITES ON LAKE OKEECHOBEE, FLORIDA, USA

    EPA Science Inventory

    Exposure to environmental contaminants has been shown to alter normal thyroid function in various wildlife species, including the American alligator (Alligator mississippiensis). Abnormalities in circulating levels of the thyroid hormone thyroxine (T4) have been reported in juven...

  8. Mercury in alligators (Alligator mississippiensis) in the southeastern United States

    USGS Publications Warehouse

    Jagoe, C.H.; Arnold-Hill, B.; Yanochko, G.M.; Winger, P.V.; Brisbin, I.L., Jr.

    1998-01-01

    Mercury methylation may be enhanced in wetlands and humic-rich, blackwater systems that crocodiles and alligators typically inhabit. Given their high trophic level and long life-spans, crocodilians could accumulate significant burdens of Hg. Our objectives were to survey Hg concentrations in alligators from several areas in the southeastern United States to test their utility as sentinels of Hg contamination, to examine relationships among Hg concentrations in various tissues and to look for any differences in tissue Hg concentrations among locations. We measured total Hg concentrations in alligators collected in the Florida Everglades (n = 18), the Okefenokee National Wildlife Refuge, Georgia (n = 9), the Savannah River Site (SRS), South Carolina (n = 49) and various locations in central Florida ( n = 21), sampling tissues including blood, brain, liver, kidney, muscle, bone, fat, spleen, claws and dermal scutes. Alligators from the Everglades were mostly juvenile, but Hg concentrations in tissues were high (means: liver 41.0, kidney 36.4, muscle 5.6 mg Hg/kg dry wt.). Concentrations in alligators from other locations in Florida were lower (means: liver 14.6, kidney 12.6, muscle 1.8 mg Hg/kg dry wt.), although they tended to be larger adults. Alligators from the Okefenokee were smallest and had the lowest Hg concentrations (means: liver 4.3, kidney 4.8, muscle 0.8 mg Hg/kg dry wt.). At some locations, alligator length was correlated with Hg concentrations in some internal organs. However, at three of the four locations, muscle Hg was not related to length. Tissue Hg concentrations were correlated at most locations; however, claw or dermal scute Hg explained less than 74% of the variation of Hg in muscle or organs, suggesting readily-obtained tissues, such as scutes or claws, have limited value for nondestructive screening of Hg in alligator populations.

  9. Biophysics of directional hearing in the American alligator (Alligator mississippiensis)

    PubMed Central

    Bierman, Hilary S.; Thornton, Jennifer L.; Jones, Heath G.; Koka, Kanthaiah; Young, Bruce A.; Brandt, Christian; Christensen-Dalsgaard, Jakob; Carr, Catherine E.; Tollin, Daniel J.

    2014-01-01

    Physiological and anatomical studies have suggested that alligators have unique adaptations for spatial hearing. Sound localization cues are primarily generated by the filtering of sound waves by the head. Different vertebrate lineages have evolved external and/or internal anatomical adaptations to enhance these cues, such as pinnae and interaural canals. It has been hypothesized that in alligators, directionality may be enhanced via the acoustic coupling of middle ear cavities, resulting in a pressure difference receiver (PDR) mechanism. The experiments reported here support a role for a PDR mechanism in alligator sound localization by demonstrating that (1) acoustic space cues generated by the external morphology of the animal are not sufficient to generate location cues that match physiological sensitivity, (2) continuous pathways between the middle ears are present to provide an anatomical basis for coupling, (3) the auditory brainstem response shows some directionality, and (4) eardrum movement is directionally sensitive. Together, these data support the role of a PDR mechanism in crocodilians and further suggest this mechanism is a shared archosaur trait, most likely found also in the extinct dinosaurs. PMID:24671963

  10. Identification and Characterization of the Androgen Receptor From the American Alligator, Alligator mississippiensis

    PubMed Central

    Miyagawa, Shinichi; Yatsu, Ryohei; Kohno, Satomi; Doheny, Brenna M.; Ogino, Yukiko; Ishibashi, Hiroshi; Katsu, Yoshinao; Ohta, Yasuhiko; Guillette, Louis J.

    2015-01-01

    Androgens are essential for the development, reproduction, and health throughout the life span of vertebrates, particularly during the initiation and maintenance of male sexual characteristics. Androgen signaling is mediated by the androgen receptor (AR), a member of the steroid nuclear receptor superfamily. Mounting evidence suggests that environmental factors, such as exogenous hormones or contaminants that mimic hormones, can disrupt endocrine signaling and function. The American alligator (Alligator mississippiensis), a unique model for ecological research in that it exhibits environment-dependent sex determination, is oviparous and long lived. Alligators from a contaminated environment exhibit low reproductive success and morphological disorders of the testis and phallus in neonates and juveniles, both associated with androgen signaling; thus, the alterations are hypothesized to be related to disrupted androgen signaling. However, this line of research has been limited because of a lack of information on the alligator AR gene. Here, we isolated A mississippiensis AR homologs (AmAR) and evaluated receptor-hormone/chemical interactions using a transactivation assay. We showed that AmAR responded to all natural androgens and their effects were inhibited by cotreatment with antiandrogens, such as flutamide, p,p′-dichlorodiphenyldichloroethylene, and vinclozolin. Intriguingly, we found a spliced form of the AR from alligator cDNA, which lacks seven amino acids within the ligand-binding domain that shows no response to androgens. Finally, we have initial data on a possible dominant-negative function of the spliced form of the AR against androgen-induced AmAR. PMID:25974402

  11. Identification and Characterization of the Androgen Receptor From the American Alligator, Alligator mississippiensis.

    PubMed

    Miyagawa, Shinichi; Yatsu, Ryohei; Kohno, Satomi; Doheny, Brenna M; Ogino, Yukiko; Ishibashi, Hiroshi; Katsu, Yoshinao; Ohta, Yasuhiko; Guillette, Louis J; Iguchi, Taisen

    2015-08-01

    Androgens are essential for the development, reproduction, and health throughout the life span of vertebrates, particularly during the initiation and maintenance of male sexual characteristics. Androgen signaling is mediated by the androgen receptor (AR), a member of the steroid nuclear receptor superfamily. Mounting evidence suggests that environmental factors, such as exogenous hormones or contaminants that mimic hormones, can disrupt endocrine signaling and function. The American alligator (Alligator mississippiensis), a unique model for ecological research in that it exhibits environment-dependent sex determination, is oviparous and long lived. Alligators from a contaminated environment exhibit low reproductive success and morphological disorders of the testis and phallus in neonates and juveniles, both associated with androgen signaling; thus, the alterations are hypothesized to be related to disrupted androgen signaling. However, this line of research has been limited because of a lack of information on the alligator AR gene. Here, we isolated A mississippiensis AR homologs (AmAR) and evaluated receptor-hormone/chemical interactions using a transactivation assay. We showed that AmAR responded to all natural androgens and their effects were inhibited by cotreatment with antiandrogens, such as flutamide, p,p'-dichlorodiphenyldichloroethylene, and vinclozolin. Intriguingly, we found a spliced form of the AR from alligator cDNA, which lacks seven amino acids within the ligand-binding domain that shows no response to androgens. Finally, we have initial data on a possible dominant-negative function of the spliced form of the AR against androgen-induced AmAR. PMID:25974402

  12. Survival and growth of American alligator (Alligator mississippiensis) hatchlings after artificial incubation and repatriation

    USGS Publications Warehouse

    Temsiripong, Y.; Woodward, A.R.; Ross, J.P.; Kubilis, P.S.; Percival, H.F.

    2006-01-01

    Hatchling American Alligators (Alligator mississippiensis) produced from artificially incubated wild eggs were returned to their natal areas (repatriated). We compared artificially incubated and repatriated hatchlings released within and outside the maternal alligator's home range with naturally incubated hatchlings captured and released within the maternal alligator's home range on Lake Apopka, Lake Griffin, and Orange Lake in Florida. We used probability of recapture and total length at approximately nine months after hatching as indices of survival and growth rates. Artificially incubated hatchlings released outside of the maternal alligator's home range had lower recapture probabilities than either naturally incubated hatchlings or artificially incubated hatchlings released near the original nest site. Recapture probabilities of other treatments did not differ significantly. Artificially incubated hatchlings were approximately 6% shorter than naturally incubated hatchlings at approximately nine months after hatching. We concluded that repatriation of hatchlings probably would not have long-term effects on populations because of the resiliency of alligator populations to alterations of early age-class survival and growth rates of the magnitude that we observed. Repatriation of hatchlings may be an economical alternative to repatriation of older juveniles for population restoration. However, the location of release may affect subsequent survival and growth. Copyright 2006 Society for the Study of Amphibians and Reptiles.

  13. Ecological studies on the American alligator (Alligator mississippiensis) on the Savannah River Plant

    SciTech Connect

    Seigel, R.A.; Brandt, L.A.; Knight, J.L.; Novak, S.S.

    1986-06-01

    The American alligator (Alligator mississippiensis) is the largest vertebrate of the Savannah River Plant (SRP), reaching a maximum length of 3.7 meters (12 feet) and weighing up to 175 kg (385 pounds). Currently, populations in coastal South Carolina are considered Threatened, whereas populations in inland areas (such as the SRP) are still Endangered. Because of their legal status and economic and ecological importance, it is important to determine the environmental impacts of SRP operations on the local alligator population. The major objectives under the Endangered Species Program of the Comprehensive Cooling Water Study (CCWS) were as follows: (1) document and compare the present status and distribution of alligators on the SRP to previous surveys, in order to determine long-term changes in population abundance; (2) establish baseline population and ecological parameters of the Steel Creek population so that the ecological effects of L-Reactor operations can be determined, and (3) conduct ecological research on the immediate impacts of thermal effluents on American alligators. Gladden et al., (1985) summarized data on previous population surveys, temporal changes in the Par Pond population, preliminary results of the Steel Creek surveys and Savannah River Ecology Laboratory (SREL) research on the effects of thermal effluents. This report summarizes the current status of the SRP population, presents data on the abundance, movement patterns and activity cycles of the Steel Creek population, and presents additional data on the effect of cooling water releases on alligator ecology and behavior.

  14. Blood and Plasma Biochemistry Reference Intervals for Wild Juvenile American Alligators ( Alligator mississippiensis ).

    PubMed

    Hamilton, Matthew T; Kupar, Caitlin A; Kelley, Meghan D; Finger, John W; Tuberville, Tracey D

    2016-07-01

    : American alligators ( Alligator mississippiensis ) are one of the most studied crocodilian species in the world, yet blood and plasma biochemistry information is limited for juvenile alligators in their northern range, where individuals may be exposed to extreme abiotic and biotic stressors. We collected blood samples over a 2-yr period from 37 juvenile alligators in May, June, and July to establish reference intervals for 22 blood and plasma analytes. We observed no effect of either sex or blood collection time on any analyte investigated. However, our results indicate a significant correlation between a calculated body condition index and aspartate aminotransferase and creatine kinase. Glucose, total protein, and potassium varied significantly between sampling sessions. In addition, glucose and potassium were highly correlated between the two point-of-care devices used, although they were significantly lower with the i-STAT 1 CG8+ cartridge than with the Vetscan VS2 Avian/Reptile Rotor. The reference intervals presented herein should provide baseline data for evaluating wild juvenile alligators in the northern portion of their range. PMID:27224213

  15. Exhaustive exercise training enhances aerobic capacity in American alligator (Alligator mississippiensis).

    PubMed

    Eme, John; Owerkowicz, Tomasz; Gwalthney, June; Blank, Jason M; Rourke, Bryan C; Hicks, James W

    2009-11-01

    The oxygen transport system in mammals is extensively remodelled in response to repeated bouts of activity, but many reptiles appear to be 'metabolically inflexible' in response to exercise training. A recent report showed that estuarine crocodiles (Crocodylus porosus) increase their maximum metabolic rate in response to exhaustive treadmill training, and in the present study, we confirm this response in another crocodilian, American alligator (Alligator mississippiensis). We further specify the nature of the crocodilian training response by analysing effects of training on aerobic [citrate synthase (CS)] and anaerobic [lactate dehydrogenase (LDH)] enzyme activities in selected skeletal muscles, ventricular and skeletal muscle masses and haematocrit. Compared to sedentary control animals, alligators regularly trained for 15 months on a treadmill (run group) or in a flume (swim group) exhibited peak oxygen consumption rates higher by 27 and 16%, respectively. Run and swim exercise training significantly increased ventricular mass (~11%) and haematocrit (~11%), but not the mass of skeletal muscles. However, exercise training did not alter CS or LDH activities of skeletal muscles. Similar to mammals, alligators respond to exercise training by increasing convective oxygen transport mechanisms, specifically heart size (potentially greater stroke volume) and haematocrit (increased oxygen carrying-capacity of the blood). Unlike mammals, but similar to squamate reptiles, alligators do not also increase citrate synthase activity of the skeletal muscles in response to exercise. PMID:19533151

  16. Levels of mercury in alligators (Alligator mississippiensis) collected along a transect through the Florida Everglades

    USGS Publications Warehouse

    Rumbold, D.G.; Fink, L.E.; Laine, K.A.; Niemczyk, S.L.; Chandrasekhar, T.; Wankel, Scott D.; Kendall, C.

    2002-01-01

    As part of a multi-agency study of alligator health, 28 American alligators (Alligator mississippiensis) were captured along a transect through the Florida Everglades in 1999. Liver and tail muscle tissues were sampled and analyzed on a wet weight basis for total mercury (THg) using cold-vapor atomic absorption spectrophotometry. All tissues had detectable concentrations of THg that ranged from 0.6 to 17 mg/kg in liver and from 0.1 to 1.8 mg/kg in tail muscle. THg was more concentrated in liver tissue than tail muscle, but levels were highly correlated between tissues. THg concentrations in tissue differed significantly among locations, with animals from Everglades National Park (ENP) having mean concentrations of THg in liver (10.4 mg/kg) and tail muscle (1.2 mg/kg) that were two-fold higher than basin-wide averages (4.9 and 0.64 mg/kg, respectively). The reasons for higher contamination of ENP alligators were unclear and could not be explained by differences in sex, length, weight or animal age. While ??15N values were positively correlated with THg concentrations in tail muscle, spatial patterns in isotopic composition did not explain the elevated THg levels in ENP alligators. Therefore, it appears that ENP alligators were more highly exposed to mercury in their environment than individuals in other areas. Comparisons to a previous survey by Yanochko et al. [Arch Environ Contam Toxicol 32 (1997) 323] suggest that mercury levels have declined in some Everglades alligators since 1994. ?? 2002 Elsevier Science B.V. All rights reserved.

  17. Endogenous and exogenous estrogens during embryonic development affect timing of hatch and growth in the American alligator (Alligator mississippiensis).

    PubMed

    Cruze, Lori; Roark, Alison M; Rolland, Gabrielle; Younas, Mona; Stacy, Nicole; Guillette, Louis J

    2015-06-01

    Prenatal exposure to estrogenic endocrine disrupting chemicals (EDCs) can affect length of gestation and body mass and size of offspring. However, the dose, timing, and duration of exposure as well as sex and strain of the experimental animals determine the direction and magnitude of these effects. In this study, we examined the effects of a one-time embryonic exposure to either 17 β-estradiol (E2) or bisphenol A (BPA) on rate of development and growth in American alligators (Alligator mississippiensis). Our results indicate that BPA and E2-treated alligators hatched approximately 1.4 days earlier than vehicle-treated (control) alligators, suggesting that estrogenic chemicals hasten hatching in these animals. We assessed growth rates, growth allometry, and body condition for 21 weeks after hatching and found that BPA-treated alligators grew more quickly shortly after hatching but more slowly thereafter compared to control alligators. Conversely, E2-treated alligators grew more slowly shortly after hatching but more quickly thereafter compared to control alligators. As a result of differences in growth rate, BPA-treated alligators were heavier, longer, and fatter than control alligators at age 5 weeks but were similar in size and leaner than control alligators at age 21 weeks. Biochemical analytes were examined at the end of the 21-week study to assess overall metabolic condition. We found that E2-treated alligators had significantly higher circulating plasma concentrations of cholesterol and triglycerides than control alligators while BPA-treated alligators had blood profiles comparable to control alligators. Our results provide important insights into the effects of exogenous estrogens on morphology and metabolism in an oviparous, semi-aquatic reptile. PMID:25687799

  18. In ovo and in vitro susceptibility of American alligators (Alligator mississippiensis) to avian influenza virus infection.

    PubMed

    Temple, Bradley L; Finger, John W; Jones, Cheryl A; Gabbard, Jon D; Jelesijevic, Tomislav; Uhl, Elizabeth W; Hogan, Robert J; Glenn, Travis C; Tompkins, S Mark

    2015-01-01

    Avian influenza has emerged as one of the most ubiquitous viruses within our biosphere. Wild aquatic birds are believed to be the primary reservoir of all influenza viruses; however, the spillover of H5N1 highly pathogenic avian influenza (HPAI) and the recent swine-origin pandemic H1N1 viruses have sparked increased interest in identifying and understanding which and how many species can be infected. Moreover, novel influenza virus sequences were recently isolated from New World bats. Crocodilians have a slow rate of molecular evolution and are the sister group to birds; thus they are a logical reptilian group to explore susceptibility to influenza virus infection and they provide a link between birds and mammals. A primary American alligator (Alligator mississippiensis) cell line, and embryos, were infected with four, low pathogenic avian influenza (LPAI) strains to assess susceptibility to infection. Embryonated alligator eggs supported virus replication, as evidenced by the influenza virus M gene and infectious virus detected in allantoic fluid and by virus antigen staining in embryo tissues. Primary alligator cells were also inoculated with the LPAI viruses and showed susceptibility based upon antigen staining; however, the requirement for trypsin to support replication in cell culture limited replication. To assess influenza virus replication in culture, primary alligator cells were inoculated with H1N1 human influenza or H5N1 HPAI viruses that replicate independent of trypsin. Both viruses replicated efficiently in culture, even at the 30 C temperature preferred by the alligator cells. This research demonstrates the ability of wild-type influenza viruses to infect and replicate within two crocodilian substrates and suggests the need for further research to assess crocodilians as a species potentially susceptible to influenza virus infection. PMID:25380354

  19. Polychlorinated biphenyls in eggs and chlorioallantoic membranes of American alligators (Alligator mississippiensis) from coastal South Carolina

    SciTech Connect

    Cobb, G.P.; Wood, P.D.; O`Quinn, M.

    1997-07-01

    Assessing chemical exposure in threatened or endangered wildlife species presents unique analytical problems. Chorioallantoic membranes (CAMs) have been proposed as surrogate tissues for evaluation of polychlorinated biphenyl (PCB) exposure in oviparous species. Research was undertaken to determine the extent of PCB accumulation in alligators (Alligator mississippiensis) at sites along the coast of South Carolina and to evaluate the utility of CAMs as surrogate tissues for determining PCB concentrations in whole alligator eggs. Polychlorinated biphenyls were found in eggs and CAMs of alligators from both sites examined. Concentrations of PCBs were higher in CAMs (p = 0.02) and eggs (p = 0.001) from sites known to contain chlorinated hydrocarbons than from more pristine sites. Total PCBs partitioned predictably (r{sup 2} > 0.59; p < 0.02) between egg and CAM tissues indicating the utility of CAMs to serve as surrogate tissues when comparing total PCB concentrations in whole eggs. Tetrachloro through octachloro biphenyl homologues and total PCBs in CAMs from reference areas were correlated with concentrations of these homologues in eggs. At contaminated sites, total PCB concentrations in CAMs were correlated with total PCB concentrations in eggs.

  20. Global DNA methylation loss associated with mercury contamination and aging in the American alligator (Alligator mississippiensis).

    PubMed

    Nilsen, Frances M; Parrott, Benjamin B; Bowden, John A; Kassim, Brittany L; Somerville, Stephen E; Bryan, Teresa A; Bryan, Colleen E; Lange, Ted R; Delaney, J Patrick; Brunell, Arnold M; Long, Stephen E; Guillette, Louis J

    2016-03-01

    Mercury is a widespread environmental contaminant with exposures eliciting a well-documented catalog of adverse effects. Yet, knowledge regarding the underlying mechanisms by which mercury exposures are translated into biological effects remains incomplete. DNA methylation is an epigenetic modification that is sensitive to environmental cues, and alterations in DNA methylation at the global level are associated with a variety of diseases. Using a liquid chromatography tandem mass spectrometry-based (LC-MS/MS) approach, global DNA methylation levels were measured in red blood cells of 144 wild American alligators (Alligator mississippiensis) from 6 sites with variable levels of mercury contamination across Florida's north-south axis. Variation in mercury concentrations measured in whole blood was highly associated with location, allowing the comparison of global DNA methylation levels across different "treatments" of mercury. Global DNA methylation in alligators across all locations was weakly associated with increased mercury exposure. However, a much more robust relationship was observed in those animals sampled from locations more highly contaminated with mercury. Also, similar to other vertebrates, global DNA methylation appears to decline with age in alligators. The relationship between age-associated loss of global DNA methylation and varying mercury exposures was examined to reveal a potential interaction. These findings demonstrate that global DNA methylation levels are associated with mercury exposure, and give insights into interactions between contaminants, aging, and epigenetics. PMID:26748003

  1. Global DNA methylation loss associated with mercury contamination and aging in the American alligator (Alligator mississippiensis)

    PubMed Central

    Nilsen, Frances M.; Parrott, Benjamin B.; Bowden, John A.; Kassim, Brittany L.; Somerville, Stephen E.; Bryan, Teresa A.; Bryan, Colleen E.; Lange, Ted R.; Delaney, J. Patrick; Brunell, Arnold M.; Long, Stephen E.; Guillette, Louis J.

    2016-01-01

    Mercury is a widespread environmental contaminant with exposures eliciting a well-documented catalog of adverse effects. Yet, knowledge regarding the underlying mechanisms by which mercury exposures are translated into biological effects remains incomplete. DNA methylation is an epigenetic modification that is sensitive to environmental cues, and alterations in DNA methylation at the global level are associated with a variety of diseases. Using a liquid chromatography tandem mass spectrometry-based (LC-MS/MS) approach, global DNA methylation levels were measured in red blood cells of 144 wild American alligators (Alligator mississippiensis) from 6 sites with variable levels of mercury contamination across Florida’s north-south axis. Variation in mercury concentrations measured in whole blood was highly associated with location, allowing the comparison of global DNA methylation levels across different “treatments” of mercury. Global DNA methylation in alligators across all locations was weakly associated with increased mercury exposure. However, a much more robust relationship was observed in those animals sampled from locations more highly contaminated with mercury. Also, similar to other vertebrates, global DNA methylation appears to decline with age in alligators. The relationship between age-associated loss of global DNA methylation and varying mercury exposures was examined to reveal a potential interaction. These findings demonstrate that global DNA methylation levels are associated with mercury exposure, and give insights into interactions between contaminants, aging, and epigenetics. PMID:26748003

  2. Morphogenesis and patterning of the phallus and cloaca in the American alligator, alligator mississippiensis.

    PubMed

    Gredler, Marissa L; Seifert, Ashley W; Cohn, Martin J

    2015-01-01

    In most animals, reproduction by internal fertilization is facilitated by an intromittent organ, such as the penis in amniote vertebrates. Recent progress has begun to uncover the mechanisms of mammalian external genital development; however, comparatively little is known about the development of the reptilian penis and clitoris. Here, we describe the development of the phallus and cloaca in the American alligator, Alligator mississippiensis. The embryonic precursor of the penis and clitoris is the genital tubercle, which forms by the budding of genital mesenchyme beneath the ventral body wall ectoderm, adjacent to the cloacal membrane. The cloacal lips develop from another pair of outgrowths, the lateral swellings. Early development of the alligator phallus, cloaca, and urogenital ducts generally resembles that of other reptiles, suggesting that differences in adult reptilian phallus and cloacal anatomy arise at later stages. The phallic sulcus is derived from the cloacal endoderm, indicating that the crocodilian sulcus is functionally and developmentally homologous to the mammalian urethra. Initial external genital outgrowth and patterning occur prior to temperature-dependent sex determination. Our analysis of alligator phallus and cloaca development suggests that modifications of an ancestral program of urogenital development could have generated the morphological diversity found in the external genitalia of modern amniotes. PMID:24993090

  3. Fluctuating water depths affect American alligator (Alligator mississippiensis) body condition in the Everglades, Florida, USA

    USGS Publications Warehouse

    Brandt, Laura A.; Beauchamp, Jeffrey S.; Jeffery, Brian M.; Cherkiss, Michael S.; Mazzotti, Frank J.

    2016-01-01

    Successful restoration of wetland ecosystems requires knowledge of wetland hydrologic patterns and an understanding of how those patterns affect wetland plant and animal populations.Within the Everglades, Florida, USA restoration, an applied science strategy including conceptual ecological models linking drivers to indicators is being used to organize current scientific understanding to support restoration efforts. A key driver of the ecosystem affecting the distribution and abundance of organisms is the timing, distribution, and volume of water flows that result in water depth patterns across the landscape. American alligators (Alligator mississippiensis) are one of the ecological indicators being used to assess Everglades restoration because they are a keystone species and integrate biological impacts of hydrological operations through all life stages. Alligator body condition (the relative fatness of an animal) is one of the metrics being used and targets have been set to allow us to track progress. We examined trends in alligator body condition using Fulton’s K over a 15 year period (2000–2014) at seven different wetland areas within the Everglades ecosystem, assessed patterns and trends relative to restoration targets, and related those trends to hydrologic variables. We developed a series of 17 a priori hypotheses that we tested with an information theoretic approach to identify which hydrologic factors affect alligator body condition. Alligator body condition was highest throughout the Everglades during the early 2000s and is approximately 5–10% lower now (2014). Values have varied by year, area, and hydrology. Body condition was positively correlated with range in water depth and fall water depth. Our top model was the “Current” model and included variables that describe current year hydrology (spring depth, fall depth, hydroperiod, range, interaction of range and fall depth, interaction of range and hydroperiod). Across all models, interaction

  4. Pathology, physiologic parameters, tissue contaminants, and tissue thiamine in morbid and healthy central Florida adult American alligators (Alligator mississippiensis).

    PubMed

    Honeyfield, Dale C; Ross, J Perran; Carbonneau, Dwayne A; Terrell, Scott P; Woodward, Allan R; Schoeb, Trenton R; Perceval, H Franklin; Hinterkopf, Joy P

    2008-04-01

    An investigation of adult alligator (Alligator mississippiensis) mortalities in Lake Griffin, central Florida, was conducted from 1998-2004. Alligator mortality was highest in the months of April and May and annual death count peaked in 2000. Bacterial pathogens, heavy metals, and pesticides were not linked with the mortalities. Blood chemistry did not point to any clinical diagnosis, although differences between impaired and normal animals were noted. Captured alligators with signs of neurologic impairment displayed unresponsive and uncoordinated behavior. Three of 21 impaired Lake Griffin alligators were found to have neural lesions characteristic of thiamine deficiency in the telencephalon, particularly the dorsal ventricular ridge. In some cases, lesions were found in the thalamus, and parts of the midbrain. Liver and muscle tissue concentrations of thiamine (vitamin B(1)) were lowest in impaired Lake Griffin alligators when compared to unimpaired alligators or to alligators from Lake Woodruff. The consumption of thiaminase-positive gizzard shad (Dorosoma cepedianum) is thought to have been the cause of the low tissue thiamine and resulting mortalities. PMID:18436661

  5. Pathology, physiologic parameters, tissue contaminants, and tissue thiamine in morbid and healthy central Florida adult American alligators (Alligator mississippiensis)

    USGS Publications Warehouse

    Honeyfield, D.C.; Ross, J.P.; Carbonneau, D.A.; Terrell, S.P.; Woodward, A.R.; Schoeb, T.R.; Perceval, H.F.; Hinterkopf, J.P.

    2008-01-01

    An investigation of adult alligator (Alligator mississippiensis) mortalities in Lake Griffin, central Florida, was conducted from 1998-2004. Alligator mortality was highest in the months of April and May and annual death count peaked in 2000. Bacterial pathogens, heavy metals, and pesticides were not linked with the mortalities. Blood chemistry did not point to any clinical diagnosis, although differences between impaired and normal animals were noted. Captured alligators with signs of neurologic impairment displayed unresponsive and uncoordinated behavior. Three of 21 impaired Lake Griffin alligators were found to have neural lesions characteristic of thiamine deficiency in the telencephalon, particularly the dorsal ventricular ridge. In some cases, lesions were found in the thalamus, and parts of the midbrain. Liver and muscle tissue concentrations of thiamine (vitamin B"1) were lowest in impaired Lake Griffin alligators when compared to unimpaired alligators or to alligators from Lake Woodruff. The consumption of thiaminase-positive gizzard shad (Dorosoma cepedianum) is thought to have been the cause of the low tissue thiamine and resulting mortalities. ?? Wildlife Disease Association 2008.

  6. Differential limb scaling in the american alligator (Alligator mississippiensis) and its implications for archosaur locomotor evolution.

    PubMed

    Livingston, Victoria J; Bonnan, Matthew F; Elsey, Ruth M; Sandrik, Jennifer L; Wilhite, D Ray

    2009-06-01

    Bipedalism evolved multiple times within archosaurs, and relatively shorter forelimbs characterize both crocodyliforms and nonavian dinosaurs. Analysis of a comprehensive ontogenetic sequence of specimens (embryo to adult) of the sauropodomorph Massospondylus has shown that bipedal limb proportions result from negative forelimb allometry. We ask, is negative forelimb allometry a pattern basal to archosaurs, amplified in certain taxa to produce bipedalism? Given the phylogenetic position of extant crocodylians and their relatively shorter forelimb, we tested the hypothesis that prevalent negative forelimb allometry is present in Alligator mississippiensis from a sample of wild specimens from embryonic to adult sizes. Long bone lengths (humerus, radius, ulna, femur, tibia, fibula, third metapodials) were measured with their epiphyseal cartilage intact at all sizes. Our results show an overall isometric pattern for most elements regressed on femur length, humerus length, or total limb length. However, negative allometry was prevalent for the ulna, and the third metapodials scale with positive allometry embryonically. These data suggest that the general forelimb proportions in relation to the hindlimb do not change significantly with increasing size in A. mississippiensis. The negative allometry of the ulna and embryonicaly positive allometry of the third metapodials appears to be related to maintaining the functional integrity of the limbs. We show that this pattern is different from that of the sauropodomorph Massospondylus, and we suggest that if bipedalism in archosaurs is tied, in part, to negative forearm allometry, it was either secondarily lost through isometric scaling, or never developed in the ancestor of A. mississippiensis. PMID:19462445

  7. Ecological studies on the American alligator (Alligator mississippiensis) on the Savannah River Plant. Comprehensive Cooling Water Study: Final report

    SciTech Connect

    Seigel, R.A.; Brandt, L.A.; Knight, J.L.; Novak, S.S.

    1986-06-01

    The American alligator (Alligator mississippiensis) is the largest vertebrate of the Savannah River Plant (SRP), reaching a maximum length of 3.7 meters (12 feet) and weighing up to 175 kg (385 pounds). Currently, populations in coastal South Carolina are considered Threatened, whereas populations in inland areas (such as the SRP) are still Endangered. Because of their legal status and economic and ecological importance, it is important to determine the environmental impacts of SRP operations on the local alligator population. The major objectives under the Endangered Species Program of the Comprehensive Cooling Water Study (CCWS) were as follows: (1) document and compare the present status and distribution of alligators on the SRP to previous surveys, in order to determine long-term changes in population abundance; (2) establish baseline population and ecological parameters of the Steel Creek population so that the ecological effects of L-Reactor operations can be determined, and (3) conduct ecological research on the immediate impacts of thermal effluents on American alligators. Gladden et al., (1985) summarized data on previous population surveys, temporal changes in the Par Pond population, preliminary results of the Steel Creek surveys and Savannah River Ecology Laboratory (SREL) research on the effects of thermal effluents. This report summarizes the current status of the SRP population, presents data on the abundance, movement patterns and activity cycles of the Steel Creek population, and presents additional data on the effect of cooling water releases on alligator ecology and behavior.

  8. Post-hatching development of Alligator mississippiensis ovary and testis

    PubMed Central

    Moore, Brandon C.; Hamlin, Heather J.; Botteri, Nicole L.; Lawler, Ashley N.; Mathavan, Ketan K.; Guillette, Louis J.

    2009-01-01

    We investigated ovary and testis development of Alligator mississippiensis during the first five months post-hatch. To better describe follicle assembly and seminiferous cord development, we employed histochemical techniques to detect carbohydrate-rich extracellular matrix components in one-week, one-month, three-month, and five-month-old gonads. We found profound morphological changes in both ovary and testis. During this time, oogenesis progressed up to diplotene arrest and meiotic germ cells increasingly interacted with follicular cells. Concomitant with follicles becoming invested with full complements of granulosa cells, a periodic acid Schiff’s (PAS)-positive basement membrane formed. As follicles enlarged and thecal layers were observed, basement membranes and thecal compartments gained periodic acid-methionine silver (PAMS)-reactive fibers. The ovarian medulla increased first PAS- and then PAMS-reactivity as it fragmented into wide lacunae lined with low cuboidal to squamous epithelia. During this same period, testicular germ cells found along the tubule margins were observed progressing from spermatogonia to round spermatids located within the center of tubules. Accompanying this meiotic development, interstitial Leydig cell clusters become more visible and testicular capsules thickened. During the observed testis development, the thickening tunica albuginea and widening interstitial tissues showed increasing PAS- and PAMS-reactivity. We observed putative inter-sex structures in both ovary and testis. On the coelomic aspect of testes were cell clusters with germ cell morphology and at the posterior end of ovaries, we observed “medullary rests” resembling immature testis cords. We hypothesize laboratory conditions accelerated gonad maturation due to optimum conditions, including nutrients and temperature. Laboratory alligators grew more rapidly and with increased body conditions compared to previous measured, field-caught animals. Additionally, we

  9. Mathematical models for growth in alligator (Alligator mississippiensis) embryos developing at different incubation temperatures.

    PubMed Central

    Bardsley, W G; Ackerman, R A; Bukhari, N A; Deeming, D C; Ferguson, M W

    1995-01-01

    A variety of model-based (growth models) and model-free (cubic splines, exponentials) equations were fitted using weighted-nonlinear least squares regression to embryonic growth data from Alligator mississippiensis eggs incubated at 30 and 33 degrees C. Goodness of fit was estimated using a chi 2 on the sum of squared, weighted residuals, and run and sign tests on the residuals. One of the growth models used (Preece & Baines, 1978) was found to be superior to the classical growth models (exponential, monomolecular, logistic, Gompertz, von Bertalanffy) and gave an adequate fit to all longitudinal measures taken from the embryonic body and embryonic mass. However, measurements taken from the head could not be fitted by growth models but were adequately fitted by weighted least squares cubic splines. Data for the stage of development were best fitted by a sum of 2 exponentials with a transition point. Comparison of the maximum growth rates and parameter values, indicated that the growth data at 30 degrees C could be scaled to 33 degrees C to multiplying the time by a scaling factor of 1.2. This is equivalent to a Q10 of about 1.86 or, after solving the Arrhenius equation, an E++ of 46.9 kJmol-1. This may be interpreted as indicating a common rate-limiting step in development at the 2 temperatures. PMID:7591979

  10. ALTERATIONS IN SEXUALLY DIMORPHIC BIOTRANSFORMATION OF TESTOSTERONE IN JUVENILE AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED LAKES

    EPA Science Inventory

    The goal of this study was to determine whether hepatic biotransformation of testosterone is normally sexually dimorphic in juvenile alligators and whether living in a contaminated environment affects hepatic dimorphism. Lake Woodruff served as our reference site. Moonshine Bay, ...

  11. MORPHOLOGICAL VARIATION IN HATCHLING AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM THREE FLORIDA LAKES

    EPA Science Inventory

    Morphological variation of 508 hatchling alligators from three lakes in north central Florida (Lakes Woodruff, Apopka, and Orange) was analyzed using multivariate statistics. Morphological variation was found among clutches as well as among lakes. Principal components analysis wa...

  12. Home range and movements of American alligators (Alligator mississippiensis) in an estuary habitat

    USGS Publications Warehouse

    Fujisaki, Ikuko; Hart, Kristen M.; Mazzotti, Frank J.; Cherkiss, Michael S.; Sartain-Iverson, Autumn R.; Jeffery, Brian M.; Beauchamp, Jeffrey S.; Denton, Mathew J.

    2014-01-01

    This study reveals consistent use of estuary habitat by American alligators. The alligators showed variations in their movement pattern and seasonal habitat, with movement attributable to environmental factors. Although satellite-derived locations were more dispersed compared to locations collected using VHF radio-tags, data collected from VHF tracking omitted some habitat used for a short period of time, indicating the effectiveness of satellite telemetry to continuously track animals for ecosystem-scale studies.

  13. Urinary Phthalate Metabolites in American Alligators (Alligator mississippiensis) from Selected Florida Wetlands.

    PubMed

    Brock, John W; Bell, Jane Margaret; Guillette, Louis J

    2016-07-01

    Phthalates have been shown to cause endocrine disruption in laboratory animals and are associated with altered development of the reproductive system in humans. Further, human have significant exposure to phthalates. However, little is known concerning the exposure of wildlife to phthalates. We report urinary phthalate metabolite concentrations from fifty juvenile alligators from three Florida lakes and a site in the Everglades. Urinary phthalate monoester concentrations varied widely among alligators from the different sites but also among alligators from the same site. Mono-2-ethylhexy phthalate and monobutyl phthalate were found in most samples of alligator urine with maximums of 35,700 ng/mL and 193 ng/mL, respectively. Monobenzyl phthalate was found in 5 alligators with a maximum of 66.7 ng/mL. Other monoesters were found in only one or two alligator urine samples. The wide variation within and among sites, in addition to the high levels of mEHP, mBP and mBzP, is consistent with exposure arising from the intermittent spraying of herbicide formulations to control invasive aquatic plants in Florida freshwater sites. Phthalate diesters are used as adjuvants in many of these formulations. PMID:26743198

  14. Computed tomography of granulomatous pneumonia with oxalosis in an American alligator (Alligator mississippiensis) associated with Metarhizium anisopliae var anisopliae.

    PubMed

    Hall, Natalie H; Conley, Kenneth; Berry, Clifford; Farina, Lisa; Sigler, Lynne; Wellehan, James F X; Roehrl, Michael H A; Heard, Darryl

    2011-12-01

    An 18-yr-old, male, albino, American alligator (Alligator mississippiensis) was evaluated for decreased appetite and abnormal buoyancy. Computed tomography (CT) of the coelomic cavity showed multifocal mineral and soft tissue attenuating pulmonary masses consistent with pulmonary fungal granulomas. Additionally, multifocal areas of generalized, severe emphysema and pulmonary and pleural thickening were identified. The alligator was euthanized and necropsy revealed severe fungal pneumonia associated with oxalosis. Metarhizium anisopliae var. anisopliae was cultured from lung tissue and exhibited oxalate crystal formation in vitro. Crystals were identified as calcium oxalate monohydrate by X-ray powder defractometry. Fungal identification was based on morphology, including tissue sporulation, and DNA sequence analysis. This organism is typically thought of as an entomopathogen. Clinical signs of fungal pneumonia in nonavian reptiles are often inapparent until the disease is at an advanced stage, making antemortem diagnosis challenging. This case demonstrates the value of CT for pulmonary assessment and diagnosis of fungal pneumonia in the American alligator. Fungal infection with associated oxalosis should not be presumed to be aspergillosis. PMID:22204066

  15. Low cost of pulmonary ventilation in American alligators (Alligator mississippiensis) stimulated with doxapram.

    PubMed

    Skovgaard, Nini; Crossley, Dane A; Wang, Tobias

    2016-04-01

    To determine the costs of pulmonary ventilation without imposing severe oxygen limitations or acidosis that normally accompany exposures to hypoxia or hypercapnia, we opted to pharmacologically stimulate ventilation with doxapram (5 and 10 mg kg(-1)) in alligators. Doxapram is used clinically to alleviate ventilatory depression in response to anaesthesia and acts primarily on the peripheral oxygen-sensitive chemoreceptors. Using this approach, we investigated the hypothesis that pulmonary ventilation is relatively modest in comparison to resting metabolic rate in crocodilians and equipped seven juvenile alligators with masks for concurrent determination of ventilation and oxygen uptake. Doxapram elicited a dose-dependent and up to fourfold rise in ventilation, primarily by increasing ventilatory frequency. The accompanying rise in oxygen uptake was very small; ventilation in resting animals constitutes no more than 5% of resting metabolic rate. The conclusion that pulmonary ventilation is energetically cheap is consistent with earlier studies on alligators where ventilation was stimulated by hypoxia or hypercapnia. PMID:26896538

  16. Periods of cardiovascular susceptibility to hypoxia in embryonic american alligators (Alligator mississippiensis).

    PubMed

    Tate, Kevin B; Rhen, Turk; Eme, John; Kohl, Zachary F; Crossley, Janna; Elsey, Ruth M; Crossley, Dane A

    2016-06-01

    During embryonic development, environmental perturbations can affect organisms' developing phenotype, a process known as developmental plasticity. Resulting phenotypic changes can occur during discrete, critical windows of development. Critical windows are periods when developing embryos are most susceptible to these perturbations. We have previously documented that hypoxia reduces embryo size and increases relative heart mass in American alligator, and this study identified critical windows when hypoxia altered morphological, cardiovascular function and cardiac gene expression of alligator embryos. We hypothesized that incubation in hypoxia (10% O2) would increase relative cardiac size due to cardiac enlargement rather than suppression of somatic growth. We exposed alligator embryos to hypoxia during discrete incubation periods to target windows where the embryonic phenotype is altered. Hypoxia affected heart growth between 20 and 40% of embryonic incubation, whereas somatic growth was affected between 70 and 90% of incubation. Arterial pressure was depressed by hypoxic exposure during 50-70% of incubation, whereas heart rate was depressed in embryos exposed to hypoxia during a period spanning 70-90% of incubation. Expression of Vegf and PdgfB was increased in certain hypoxia-exposed embryo treatment groups, and hypoxia toward the end of incubation altered β-adrenergic tone for arterial pressure and heart rate. It is well known that hypoxia exposure can alter embryonic development, and in the present study, we have identified brief, discrete windows that alter the morphology, cardiovascular physiology, and gene expression in embryonic American alligator. PMID:27101296

  17. Perfluorinated Alkyl Acids in Plasma of American Alligators (Alligator Mississippiensis) from Florida and South Carolina

    NASA Technical Reports Server (NTRS)

    Bangma, Jacqueline T.; Bowden, John A.; Brunell, Arnold M.; Christie, Ian; Finnell, Brendan; Guillette, Matthew P.; Jones, Martin; Lowers, Russell H.; Rainwater, Thomas R.; Reiner, Jessica L.; Wilkinson, Philip M.; Guillette, Louis J., Jr.

    2016-01-01

    This study aimed to quantitate fourteen perfluoroalkyl acids (PFAAs) in 125 adult American alligators at twelve sites across the southeastern US. Of those fourteen PFAAs, nine were detected in 65% - 100% of the samples: PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTriA, PFTA, PFHxS, and PFOS. Males (across all sites) showed significantly higher concentrations of four PFAAs: PFOS (p = 0.01), PFDA (p = 0.0003), PFUnA (p = 0.021), and PFTriA (p = 0.021). Concentrations of PFOS, PFHxS, and PFDA in plasma were significantly different among the sites in each sex. Alligators at Merritt Island National Wildlife Refuge and Kiawah Nature Conservancy both exhibited some of the highest PFOS concentrations (medians 99.5 ng/g and 55.8 ng/g respectively) in plasma measured to date in a crocodilian species. A number of positive correlations between PFAAs and snout-vent length (SVL) were observed in both sexes suggesting PFAA body burdens increase with increasing size. In addition, several significant correlations among PFAAs in alligator plasma may suggest conserved sources of PFAAs at each site throughout the greater study area. This study is the first to report PFAAs in American alligators, reveals potential PFAA hot spots in Florida and South Carolina, and provides and additional contaminant of concern when assessing anthropogenic impacts on ecosystem health.

  18. Variations in hepatic biomarkers in American alligators (Alligator mississippiensis) from three sites in Florida, USA.

    PubMed

    Gunderson, Mark P; Pickett, Melissa A; Martin, Justin T; Hulse, Elizabeth J; Smith, Spenser S; Smith, Levi A; Campbell, Rachel M; Lowers, Russell H; Boggs, Ashley S P; Guillette, Louis J

    2016-07-01

    Sub-individual biomarkers are sub-lethal biological responses commonly used in the assessment of wildlife exposure to environmental contaminants. In this study, we examined the activity of glutathione-s-transferase (GST) and lactate dehydrogenase (LDH), and metallothionein (MT) concentrations among captive-raised alligator hatchlings, wild-caught juveniles, and wild-caught adults. Juveniles and adults were collected from three locations in Florida (USA) with varying degrees of contamination (i.e. Lake Apopka (organochlorine polluted site), Merritt Island National Wildlife Refuge (NWR) (metal polluted site), and Lake Woodruff NWR (reference site)). We examined whether changes in the response of these three biomarkers were age and sex dependent or reflected site-specific variations of environmental contaminants. Juvenile alligators from Merritt Island NWR had higher MT concentrations and lower GST activity compared to those from the other two sites. This outcome was consistent with higher metal pollution at this location. Sexually dimorphic patterns of MT and GST (F > M) were observed in juvenile alligators from all sites, although this pattern was not observed in adults. GST activity was lower in captive-raised alligators from Lake Apopka and Merritt Island NWR as compared to animals from Lake Woodruff NWR, suggesting a possible developmental modulator at these sites. No clear patterns were observed in LDH activity. We concluded that GST and MT demonstrate age and sex specific patterns in the alligators inhabiting these study sites and that the observed variation among sites could be due to differences in contaminant exposure. PMID:27111470

  19. Influence of collection time on hematologic and immune markers in the American alligator (Alligator mississippiensis).

    PubMed

    Finger, John W; Williams, Robert J; Hamilton, Matthew T; Elsey, Ruth M; Oppenheimer, Victor A; Holladay, Steven D; Gogal, Robert M

    2015-01-01

    Crocodilians are important keystone species and indicators of environmental health. Much remains unknown, however regarding utility of field-collected crocodilian blood samples for ecologic assessments. Field sampling sites are also often distant to analysis centers, necessitating development of new techniques and panels of assays that will yield environmentally relevant data. Stability and viability of hematological and immunological indices have been of particular interest for linking ecosystem health to biomarkers in resident species. In this study, we investigated the effect of time at analysis post-blood sampling at 4 and 24 hr on a panel of potential biomarkers in alligator blood. Our results suggest alligator blood samples can be reliably evaluated for both hematologic and immunologic profile 24 hr after sampling. PMID:25560415

  20. Morphology and histochemistry of juvenile male American alligator (Alligator mississippiensis) phallus.

    PubMed

    Moore, Brandon C; Mathavan, Ketan; Guillette, Louis J

    2012-02-01

    Phalli of male crocodilians transfer sperm to female cloaca during sexual intercourse, resulting in internal fertilization. For over a century there have been scientific descriptions of crocodilian phallus morphologies; however, little work has presented detailed cellular-level analyses of these structures. Here we present a histological investigation of the complex functional anatomy of the juvenile male American alligator phallus, including fibrous and vascular erectile structures, a variety of secretory epithelium morphologies, and observed immune cells. Using 3D reconstruction software, we show the shape and location of vascular erectile tissues within the phallus. Histochemical staining detected mucin-rich secretory cells in glandular epithelial cells of the phallic shaft and also of the semen-conducting ventral sulcus. Lymphoid aggregates, lymphocytes, and epithelial mucin coats suggest an active immune system in the phallus defending from both the external and intracloacal environments. These results better characterize the complexity of the alligator phallus and predict later reproductive functions during adulthood. PMID:22190479

  1. Development of sympathetic cardiovascular control in embryonic, hatchling, and yearling female American alligator (Alligator mississippiensis).

    PubMed

    Eme, John; Elsey, Ruth M; Crossley, Dane A

    2013-06-01

    We used arterial tyramine injections to study development of sympathetic actions on in vivo heart rate and blood pressure in embryonic, hatching and yearling female American alligators. Tyramine is a pharmacological tool for understanding comparative and developmental sympathetic regulation of cardiovascular function, and this indirect sympathomimetic agent causes endogenous neuronal catecholamine release, increasing blood pressure and heart rate. Arterial tyramine injection in hatchling and yearling alligators caused the typical vertebrate response - rise in heart rate and blood pressure. However, in embryonic alligators, tyramine caused a substantial and immediate bradycardia at both 70% and 90% of embryonic development. This embryonic bradycardia was accompanied by hypotension, followed by a sustained hypertension similar to the hatchling and juvenile responses. Pretreatment with atropine injection (cholinergic receptor blocker) eliminated the embryonic hypotensive bradycardia, and phentolamine pretreatment (α-adrenergic receptor blocker) eliminated the embryonic hypotensive and hypertensive responses but not the bradycardia. In addition, hexamethonium pretreatment (nicotinic receptor blocker) significantly blunted embryos' bradycardic tyramine response. However, pretreatment with 6-hydroxydopamine, a neurotoxin that destroys catecholaminergic terminals, did not eliminate the embryonic bradycardia. Tyramine likely stimulated a unique embryonic response - neurotransmitter release from preganglionic nerve terminals (blocked with hexamethonium) and an acetylcholine mediated bradycardia with a secondary norepinephrine-dependent sustained hypertension. In addition, tyramine appears to stimulate sympathetic nerve terminals directly, which contributed to the overall hypertension in the embryonic, hatchling and yearling animals. Data demonstrated that humoral catecholamine control of cardiovascular function was dominant over the immature parasympathetic nervous system

  2. Detection of Antibodies to a Pathogenic Mycoplasma in American Alligators (Alligator mississippiensis), Broad-Nosed Caimans (Caiman latirostris), and Siamese Crocodiles (Crocodylus siamensis)

    PubMed Central

    Brown, D. R.; Schumacher, I. M.; Nogueira, M. F.; Richey, L. J.; Zacher, L. A.; Schoeb, T. R.; Vliet, K. A.; Bennett, R. A.; Jacobson, E. R.; Brown, M. B.

    2001-01-01

    An epidemic of pneumonia with fibrinous polyserositis and multifocal arthritis emerged in captive American alligators (Alligator mississippiensis) in Florida, United States, in 1995. Mycoplasma alligatoris sp. nov. was cultured from multiple organs, peripheral blood, synovial fluid, and cerebrospinal fluid of affected alligators. In a subsequent experimental inoculation study, the Henle-Koch-Evans postulates were fulfilled for M. alligatoris as the etiological agent of fatal mycoplasmosis of alligators. That finding was remarkable because mycoplasmal disease is rarely fatal in animals. An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies produced by alligators in response to M. alligatoris exposure was developed by using plasma obtained from naturally infected alligators during the original epidemic. The assay was validated by using plasma obtained during an experimental dose-response study and applied to analyze plasma obtained from captive and wild crocodilian species. The ELISA reliably detected alligator seroconversion (P < 0.05) beginning 6 weeks after inoculation. The ELISA also detected seroconversion (P < 0.05) in the relatively closely related broad-nosed caiman Caiman latirostris and the relatively distantly related Siamese crocodile Crocodylus siamensis following experimental inoculation with M. alligatoris. The ELISA may be used to monitor exposure to the lethal pathogen M. alligatoris among captive, repatriated, and wild crocodilian species. PMID:11136785

  3. Validation and use of an indirect enzyme-linked immunosorbent assay for detection of antibodies to West Nile virus in American Alligators (Alligator mississippiensis) in Florida.

    PubMed

    Jacobson, Elliott R; Johnson, April J; Hernandez, Jorge A; Tucker, Sylvia J; Dupuis, Alan P; Stevens, Robert; Carbonneau, Dwayne; Stark, Lillian

    2005-01-01

    In October 2002, West Nile virus (WNV) was identified in farmed American alligators (Alligator mississippiensis) in Florida showing clinical signs and having microscopic lesions indicative of central nervous system disease. To perform seroepidemiologic studies, an indirect enzyme-linked immunosorbent assay (ELISA) was developed to determine exposure of captive and wild alligators to WNV. To validate the test, a group of WNV-seropositive and -seronegative alligators were identified at the affected farm using hemagglutination inhibition (HAI) and the plaque reduction neutralization test (PRNT). The indirect ELISA utilized a rabbit anti-alligator immunoglobulins polyclonal antibody as the secondary antibody, and inactivated WNV-infected Vero cells were used as the coating antigen. For all samples (n=58), the results of the ELISA were consistent with the HAI and PRNT findings. Plasma was collected from 669 free-ranging alligators from 21 sites across Florida in April and October 2003. Four samples collected in April and six in October were positive for WNV antibodies using HAI, PRNT, and the indirect ELISA. This indicated that wild alligators in Florida have been exposed to WNV. These findings can be used as a baseline for future surveys. PMID:15827216

  4. Concentrations of trace elements in American alligators (Alligator mississippiensis) from Florida, USA.

    PubMed

    Horai, Sawako; Itai, Takaaki; Noguchi, Takako; Yasuda, Yusuke; Adachi, Haruki; Hyobu, Yuika; Riyadi, Adi S; Boggs, Ashley S P; Lowers, Russell; Guillette, Louis J; Tanabe, Shinsuke

    2014-08-01

    Concentrations of 28 trace elements (Li, Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Tl, Hg, Pb, and Bi) in the livers of juvenile and adult American alligators inhabiting two central Florida lakes, Lake Apopka (LA), and Lake Woodruff National Wildlife Refuge (LW) and one lagoon population located in Merritt Island National Wildlife Refuge (MINWR; NASA), were determined. In juveniles from MINWR, concentrations of nine elements (Li, Fe, Ni, Sr, In, Sb, Hg, Pb and Bi) were significantly higher, whereas six elements (V, Fe, As, Sr, Hg and Bi) were elevated in adults (p<0.05) obtained from MINWR. Significant enrichment of some trace elements in adults, relative to juveniles, was observed at all three sampling areas. Specifically, Fe, Pb and Hg were significantly elevated in adults when compared to juveniles, suggesting age-dependent accumulation of these elements. Further, As, Se and Sn showed the same trend but only in animals collected from MINWR. Mean Fe concentrations in the livers of adults from LA, LW and MINWR were 1770 μg g(-1) DW, 3690 μg g(-1) DW and 5250 μg g(-1) DW, respectively. More than half of the adult specimens from LW and MINWR exhibited elevated hepatic Fe concentrations that exceed the threshold value for toxic effects in donkey, red deer and human. These results prompted us to express our concern on possible exposure and health effects in American alligators by some trace elements derived from NASA activities. PMID:24698170

  5. Mechanics of limb bone loading during terrestrial locomotion in the green iguana (Iguana iguana) and American alligator (Alligator mississippiensis).

    PubMed

    Blob, R W; Biewener, A A

    2001-03-01

    In vivo measurements of strain in the femur and tibia of Iguana iguana (Linnaeus) and Alligator mississippiensis (Daudin) have indicated three ways in which limb bone loading in these species differs from patterns observed in most birds and mammals: (i) the limb bones of I. iguana and A. mississippiensis experience substantial torsion, (ii) the limb bones of I. iguana and A. mississippiensis have higher safety factors than those of birds or mammals, and (iii) load magnitudes in the limb bones of A. mississippiensis do not decrease uniformly with the use of a more upright posture. To verify these patterns, and to evaluate the ground and muscle forces that produce them, we collected three-dimensional kinematic and ground reaction force data from subadult I. iguana and A. mississippiensis using a force platform and high-speed video. The results of these force/kinematic studies generally confirm the loading regimes inferred from in vivo strain measurements. The ground reaction force applies a torsional moment to the femur and tibia in both species; for the femur, this moment augments the moment applied by the caudofemoralis muscle, suggesting large torsional stresses. In most cases, safety factors in bending calculated from force/video data are lower than those determined from strain data, but are as high or higher than the safety factors of bird and mammal limb bones in bending. Finally, correlations between limb posture and calculated stress magnitudes in the femur of I. iguana confirm patterns observed during direct bone strain recordings from A. mississippiensis: in more upright steps, tensile stresses on the anterior cortex decrease, but peak compressive stresses on the dorsal cortex increase. Equilibrium analyses indicate that bone stress increases as posture becomes more upright in saurians because the ankle and knee extensor muscles exert greater forces during upright locomotion. If this pattern of increased bone stress with the use of a more upright posture is

  6. Achieving environmentally relevant organochlorine pesticide concentrations in eggs through maternal exposure in Alligator mississippiensis

    USGS Publications Warehouse

    Rauschenberger, R.H.; Wiebe, J.J.; Buckland, J.E.; Smith, Joe T.; Sepulveda, M.S.; Gross, T.S.

    2004-01-01

    Alligator mississippiensis eggs from organochlorine pesticide (OCP) contaminated sites in Florida exhibit high rates of embryonic mortality compared to reference sites (p<0.05). The objective of the present study was to use captive adult alligators to test the hypotheses that maternal exposure to OCPs results in increased OCP concentrations in eggs, and that increased exposure is associated with increased embryonic mortality. A total of 24 adult alligators (8 males and 16 females) were housed in eight pens. Eight females in four pens were dosed with a mixture of p,p'-DDE, toxaphene, dieldrin, and chlordane at a rate of 0.2 ? 0.01 mg/kg/day for 274 ? 8 days. Treated females produced eggs containing higher OCP concentrations (12,814 ? 813 ng/g yolk) than controls (38 ? 4 ng/g yolk). Eggs of treated females exhibited decreased viability (13 ? 22%) as compared to controls (45 ? 20%). Results indicated that 0.6% of administered OCPs were maternally transferred to the eggs of American alligators, and that maternal exposure is associated with decreased egg/embryo viability in this species.

  7. Gastric nematode diversity between estuarine and inland freshwater populations of the American alligator (Alligator mississippiensis, daudin 1802), and the prediction of intermediate hosts

    PubMed Central

    Tellez, Marisa; Nifong, James

    2014-01-01

    We examined the variation of stomach nematode intensity and species richness of Alligator mississippiensis from coastal estuarine and inland freshwater habitats in Florida and Georgia, and integrated prey content data to predict possible intermediate hosts. Nematode parasitism within inland freshwater inhabiting populations was found to have a higher intensity and species richness than those inhabiting coastal estuarine systems. This pattern potentially correlates with the difference and diversity of prey available between inland freshwater and coastal estuarine habitats. Increased consumption of a diverse array of prey was also correlated with increased nematode intensity in larger alligators. Parasitic nematodes Dujardinascaris waltoni, Brevimulticaecum tenuicolle, Ortleppascaris antipini, Goezia sp., and Contracaecum sp. were present in alligators from both habitat types. Dujardinascaris waltoni, B. tenuicolle, and O. antipini had a significantly higher abundance among inland inhabiting alligators than hosts from estuarine populations. Our findings also suggest that host specific nematode parasites of alligators may have evolved to infect multiple intermediate hosts, particularly fishes, crabs, and turtles, perhaps in response to the opportunistic predatory behaviors of alligators. PMID:25426417

  8. Seasonal acclimatisation of muscle metabolic enzymes in a reptile (Alligator mississippiensis).

    PubMed

    Seebacher, Frank; Guderley, Helga; Elsey, Ruth M; Trosclair, Phillip L

    2003-04-01

    Reptiles living in heterogeneous thermal environments are often thought to show behavioural thermoregulation or to become inactive when environmental conditions prevent the achievement of preferred body temperatures. By contrast, thermally homogeneous environments preclude behavioural thermoregulation, and ectotherms inhabiting these environments (particularly fish in which branchial respiration requires body temperature to follow water temperature) modify their biochemical capacities in response to long-term seasonal temperature fluctuations. Reptiles may also be active at seasonally varying body temperatures and could, therefore, gain selective advantages from regulating biochemical capacities. Hence, we tested the hypothesis that a reptile (the American alligator Alligator mississippiensis) that experiences pronounced seasonal fluctuations in body temperature will show seasonal acclimatisation in the activity of its metabolic enzymes. We measured body temperatures of alligators in the wild in winter and summer (N=7 alligators in each season), and we collected muscle samples from wild alligators (N=31 in each season) for analysis of metabolic enzyme activity (lactate dehydrogenase, citrate synthase and cytochrome c oxidase). There were significant differences in mean daily body temperatures between winter (15.66+/-0.43 degrees C; mean +/- S.E.M.) and summer (29.34+/-0.21 degrees C), and daily body temperatures fluctuated significantly more in winter compared with summer. Alligators compensated for lower winter temperatures by increasing enzyme activities, and the activities of cytochrome c oxidase and lactate dehydrogenase were significantly greater in winter compared with summer at all assay temperatures. The activity of citrate synthase was significantly greater in the winter samples at the winter body temperature (15 degrees C) but not at the summer body temperature (30 degrees C). The thermal sensitivity (Q(10)) of mitochondrial enzymes decreased

  9. Functional morphology of the Alligator mississippiensis larynx with implications for vocal production.

    PubMed

    Riede, Tobias; Li, Zhiheng; Tokuda, Isao T; Farmer, Colleen G

    2015-04-01

    Sauropsid vocalization is mediated by the syrinx in birds and the larynx in extant reptiles; but whereas avian vocal production has received much attention, the vocal mechanism of basal reptilians is poorly understood. The American alligator (Alligator mississippiensis) displays a large vocal repertoire during mating and in parent-offspring interactions. Although vocal outputs of these behaviors have received some attention, the underlying mechanism of sound production remains speculative. Here, we investigate the laryngeal anatomy of juvenile and adult animals by macroscopic and histological methods. Observations of the cartilaginous framework and associated muscles largely corroborate earlier findings, but one muscle, the cricoarytenoideus, exhibits a heretofore unknown extrinsic insertion that has important implications for effective regulation of vocal fold length and tension. Histological investigation of the larynx revealed a layered vocal fold morphology. The thick lamina propria consists of non-homogenous extracellular matrix containing collagen fibers that are tightly packed below the epithelium but loosely organized deep inside the vocal fold. We found few elastic fibers but comparatively high proportions of hyaluronan. Similar organizational complexity is also seen in mammalian vocal folds and the labia of the avian syrinx: convergent morphologies that suggest analogous mechanisms for sound production. In tensile tests, alligator vocal folds demonstrated a linear stress-strain behavior in the low strain region and nonlinear stress responses at strains larger than 15%, which is similar to mammalian vocal fold tissue. We have integrated morphological and physiological data in a two-mass vocal fold model, providing a systematic description of the possible acoustic space that could be available to an alligator larynx. Mapping actual call production onto possible acoustic space validates the model's predictions. PMID:25657203

  10. AFFINITY OF THE ALLIGATOR ESTROGEN RECEPTOR FOR SERUM PESTICIDE CONTAMINANTS

    EPA Science Inventory

    Top predators, like the American alligator (Alligator mississippiensis) bioaccumulate and biomagnify persistent pollutants, such as organochlorine pesticides. In a recently published study, several pesticides and pesticide metabolites not previously reported in alligator eggs wer...

  11. Chronic Ingestion of Coal Fly-Ash Contaminated Prey and Its Effects on Health and Immune Parameters in Juvenile American Alligators (Alligator mississippiensis).

    PubMed

    Finger, John W; Hamilton, Matthew T; Metts, Brian S; Glenn, Travis C; Tuberville, Tracey D

    2016-10-01

    Coal-burning power plants supply approximately 37 % of the electricity in the United States. However, incomplete combustion produces ash wastes enriched with toxic trace elements that have historically been disposed of in aquatic basins. Organisms inhabiting such habitats may accumulate these trace elements; however, studies investigating the effects on biota have been primarily restricted to shorter-lived, lower-trophic organisms. The American alligator (Alligator mississippiensis), a long-lived, top-trophic carnivore, has been observed inhabiting these basins, yet the health or immune effects of chronic exposure and possible accumulation remains unknown. In this study, we investigated how chronic dietary ingestion of prey contaminated with coal combustion wastes (CCWs) for 25 months, and subsequent accumulation of trace elements present in CCWs, affected juvenile alligator immune function and health. Alligators were assigned to one of four dietary-treatment groups including controls and those fed prey contaminated with CCWs for one, two, or three times a week. However, no effect of Dietary Treatment (p > 0.05) was observed on any immune parameter or hematological or plasma analyte we tested. Our results suggest that neither exposure to nor accumulation of low doses of CCWs had a negative effect on certain aspects of the immune and hematological system. However, future studies are required to elucidate this further. PMID:27475646

  12. Do egg-laying crocodilian (Alligator mississippiensis) archosaurs form medullary bone?

    PubMed

    Schweitzer, M H; Elsey, R M; Dacke, C G; Horner, J R; Lamm, E-T

    2007-04-01

    It is beyond question that Mesozoic dinosaurs, like Aves and Crocodylia, are archosaurs. However, within the archosaurian clade, the origin and distribution of some major features are less clear, particularly with respect to reproductive physiology. Medullary bone, a highly mineralized, bony reproductive tissue present in the endosteal cavities of all extant egg-laying birds thus far examined, has recently been reported in Tyrannosaurus rex. Its presence or absence in extant crocodilians, therefore, may shed light on the timing of its evolutionary appearance. If medullary bone is present in all three taxa, it arose before the three lineages diverged. However, if medullary bone arose after this divergence, it may be present in both extinct dinosaurs and birds, or in birds only. If present in extinct dinosaurs and birds, but not crocodilians, it would indicate that it arose in the common ancestor of this clade, thus adding support to the closer phylogenetic relationship of dinosaurs and birds relative to crocodilians. Thus, the question of whether the crocodilian Alligator mississippiensis forms medullary bone during the production of eggs has important evolutionary significance. Our examination of long bones from several alligators (two alligators with eggs in the oviducts, one that had produced eggs in the past but was not currently in reproductive phase, an immature female and an adult male) shows no differences on the endosteal surfaces of the long bones, and no evidence of medullary bone, supporting the hypothesis that medullary bone first evolved in the dinosaur-bird line, after the divergence of crocodilians from this lineage. PMID:17223615

  13. Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology

    PubMed Central

    Horner, John R.; Farlow, James O.

    2014-01-01

    Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe the bone microstructure and quantify the histovariability of appendicular elements and osteoderms from three juvenile American alligators (Alligator mississippiensis) to assess growth mark and tissue organization within and amongst individuals, with the intention of validating paleohistological interpretations. Results confirm previous observations that lamellar and parallel fibered tissue organization are typical of crocodylians, and also that crocodylians are capable of forming woven tissue for brief periods. Tissue organization and growth mark count varies across individual skeletal elements and reveal that the femur, tibia, and humerus had the highest annual apposition rates in each individual. Cyclical growth mark count also varies intraskeletally, but data suggest these inconsistencies are due to differing medullary cavity expansion rates. There was no appreciable difference in either diaphyseal circumference or cyclical growth mark circumferences between left and right element pairs from an individual if diaphyses were sampled from roughly the same location. The considerable intraskeletal data obtained here provide validation for long-held paleohistology assumptions, but because medullary expansion, cyclical growth mark formation, and variable intraskeletal growth rates are skeletal features found in tetrapod taxa living or extinct, the validations presented herein should be considered during any tetrapod bone microanalysis. PMID:24949239

  14. Trigeminal nerve morphology in Alligator mississippiensis and its significance for crocodyliform facial sensation and evolution.

    PubMed

    George, Ian D; Holliday, Casey M

    2013-04-01

    Modern crocodylians possess a derived sense of face touch, in which numerous trigeminal nerve-innervated dome pressure receptors speckle the face and mandible and sense mechanical stimuli. However, the morphological features of this system are not well known, and it remains unclear how the trigeminal system changes during ontogeny and how it scales with other cranial structures. Finally, when this system evolved within crocodyliforms remains a mystery. Thus, new morphological insights into the trigeminal system of extant crocodylians may offer new paleontological tools to investigate this evolutionary transformation. A cross-sectional study integrating histological, morphometric, and 3D imaging analyses was conducted to identify patterns in cranial nervous and bony structures of Alligator mississippiensis. Nine individuals from a broad size range were CT-scanned followed by histomorphometric sampling of mandibular and maxillary nerve divisions of the trigeminal nerve. Endocast volume, trigeminal fossa volume, and maxillomandibular foramen size were compared with axon counts from proximal and distal regions of the trigeminal nerves to identify scaling properties of the structures. The trigeminal fossa has a significant positive correlation with skull length and endocast volume. We also found that axon density is greater in smaller alligators and total axon count has a significant negative correlation with skull size. Six additional extant and fossil crocodyliforms were included in a supplementary scaling analysis, which found that size was not an accurate predictor of trigeminal anatomy. This suggests that phylogeny or somatosensory adaptations may be responsible for the variation in trigeminal ganglion and nerve size in crocodyliforms. PMID:23408584

  15. Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology.

    PubMed

    Woodward, Holly N; Horner, John R; Farlow, James O

    2014-01-01

    Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe the bone microstructure and quantify the histovariability of appendicular elements and osteoderms from three juvenile American alligators (Alligator mississippiensis) to assess growth mark and tissue organization within and amongst individuals, with the intention of validating paleohistological interpretations. Results confirm previous observations that lamellar and parallel fibered tissue organization are typical of crocodylians, and also that crocodylians are capable of forming woven tissue for brief periods. Tissue organization and growth mark count varies across individual skeletal elements and reveal that the femur, tibia, and humerus had the highest annual apposition rates in each individual. Cyclical growth mark count also varies intraskeletally, but data suggest these inconsistencies are due to differing medullary cavity expansion rates. There was no appreciable difference in either diaphyseal circumference or cyclical growth mark circumferences between left and right element pairs from an individual if diaphyses were sampled from roughly the same location. The considerable intraskeletal data obtained here provide validation for long-held paleohistology assumptions, but because medullary expansion, cyclical growth mark formation, and variable intraskeletal growth rates are skeletal features found in tetrapod taxa living or extinct, the validations presented herein should be considered during any tetrapod bone microanalysis. PMID:24949239

  16. In vivo bone strain and finite element modeling of the mandible of Alligator mississippiensis

    PubMed Central

    Porro, Laura B; Metzger, Keith A; Iriarte-Diaz, Jose; Ross, Callum F

    2013-01-01

    Forces experienced during feeding are thought to strongly influence the morphology of the vertebrate mandible; in vivo strain data are the most direct evidence for deformation of the mandible induced by these loading regimes. Although many studies have documented bone strains in the mammalian mandible, no information is available on strain magnitudes, orientations or patterns in the sauropsid lower jaw during feeding. Furthermore, strain gage experiments record the mechanical response of bone at a few locations, not across the entire mandible. In this paper, we present bone strain data recorded at various sites on the lower jaw of Alligator mississippiensis during in vivo feeding experiments. These data are used to understand how changes in loading regime associated with changes in bite location are related to changes in strain regime on the working and balancing sides of the mandible. Our results suggest that the working side mandible is bent dorsoventrally and twisted about its long-axis during biting, and the balancing side experiences primarily dorsoventral bending. Strain orientations are more variable on the working side than on the balancing side with changes in bite point and between experiments; the balancing side exhibits higher strain magnitudes. In the second part of this paper, we use principal strain orientations and magnitudes recorded in vivo to evaluate a finite element model of the alligator mandible. Our comparison demonstrates that strain orientations and mandibular deformation predicted by the model closely match in vivo results; however, absolute strain magnitudes are lower in the finite element model. PMID:23855772

  17. Animal-borne imaging reveals novel insights into the foraging behaviors and Diel activity of a large-bodied apex predator, the American alligator (Alligator mississippiensis).

    PubMed

    Nifong, James C; Nifong, Rachel L; Silliman, Brian R; Lowers, Russell H; Guillette, Louis J; Ferguson, Jake M; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

    2014-01-01

    Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam) to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis) in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour) as well as the probability of prey-capture success (mean = 0.52 per attack) were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals' experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal-borne imaging when

  18. Animal-Borne Imaging Reveals Novel Insights into the Foraging Behaviors and Diel Activity of a Large-Bodied Apex Predator, the American Alligator (Alligator mississippiensis)

    PubMed Central

    Nifong, James C.; Nifong, Rachel L.; Silliman, Brian R.; Lowers, Russell H.; Guillette, Louis J.; Ferguson, Jake M.; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

    2014-01-01

    Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam) to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis) in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour) as well as the probability of prey-capture success (mean = 0.52 per attack) were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals’ experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal

  19. Chronic hypercapnic incubation increases relative organ growth and reduces blood pressure of embryonic American alligator (Alligator mississippiensis).

    PubMed

    Eme, John; Crossley, Dane A

    2015-04-01

    Reptilian nests can experience natural hypoxic and hypercapnic conditions. We incubated alligator eggs at a female-only producing temperature (30°C) in three conditions: 21% O2/0.04% CO2, 21% O2/3.5% CO2 and 21% O2/7% CO2. Alligator embryos chronically incubated in high CO2 were markedly hypotensive (blood pressure reduced by 46%) and had relatively (mass-specific) enlarged hearts (dry mass increased by 20%), lungs (dry mass increased by 17%), and kidneys (dry mass increased by 14%). This study is the first to chronically incubate reptilian eggs in hypercapnia and suggests that high CO2 alters the cardiovascular phenotype of alligator embryos (low blood pressure, relatively enlarged hearts), as well as the relative size of the organs primarily responsible for acid base balance, lungs and kidneys. The lungs and kidneys are largely non-functional during embryonic development, and the embryonic phenotype of increased relative mass may be a predictive-adaptation to metabolic or respiratory acidosis, such as during exercise or high respiratory CO2. This study demonstrates that phenotypic plasticity of alligator embryos incubated in high CO2 may result in either preferential organ growth, or maintenance of organ growth with reduced somatic growth. PMID:25499241

  20. Olfactory and solitary chemosensory cells: two different chemosensory systems in the nasal cavity of the American alligator, Alligator mississippiensis

    PubMed Central

    Hansen, Anne

    2007-01-01

    Background The nasal cavity of all vertebrates houses multiple chemosensors, either innervated by the Ist (olfactory) or the Vth (trigeminal) cranial nerve. Various types of receptor cells are present, either segregated in different compartments (e.g. in rodents) or mingled in one epithelium (e.g. fish). In addition, solitary chemosensory cells have been reported for several species. Alligators which seek their prey both above and under water have only one nasal compartment. Information about their olfactory epithelium is limited. Since alligators seem to detect both volatile and water-soluble odour cues, I tested whether different sensory cell types are present in the olfactory epithelium. Results Electron microscopy and immunocytochemistry were used to examine the sensory epithelium of the nasal cavity of the American alligator. Almost the entire nasal cavity is lined with olfactory (sensory) epithelium. Two types of olfactory sensory neurons are present. Both types bear cilia as well as microvilli at their apical endings and express the typical markers for olfactory neurons. The density of these olfactory neurons varies along the nasal cavity. In addition, solitary chemosensory cells innervated by trigeminal nerve fibres, are intermingled with olfactory sensory neurons. Solitary chemosensory cells express components of the PLC-transduction cascade found in solitary chemosensory cells in rodents. Conclusion The nasal cavity of the American alligator contains two different chemosensory systems incorporated in the same sensory epithelium: the olfactory system proper and solitary chemosensory cells. The olfactory system contains two morphological distinct types of ciliated olfactory receptor neurons. PMID:17683564

  1. Sex-steroid and thyroid hormone concentrations in juvenile alligators (Alligator mississippiensis) from contaminated and reference lakes in Florida, USA

    USGS Publications Warehouse

    Grain, D.A.; Guillette, L.J., Jr.; Pickford, D.B.; Percival, H.F.; Woodward, A.R.

    1998-01-01

    Sex-steroid and thyroid hormones are critical regulators of growth and reproduction in all vertebrates, and several recent studies suggest that environmental chemicals can alter circulating concentrations of these hormones. This study examines plasma concentrations of estradiol-171?? (E2), testosterone (T), triiodothyronine (T3), and thyroxine (T4) in juvenile alligators (60-140 cm total length) from two contaminated lakes and one reference lake in Florida. First, the data were analyzed by comparing hormone concentrations among males and females from the different lakes. Whereas there were no differences in plasma E2 concentrations among animals of the three lakes, male alligators from the contaminated lakes (Lake Apopka and Lake Okeechobee) had significantly lower plasma T concentrations compared 10 males from the reference take (Lake Woodruff). Concentrations of thyroid hormones also differed in animals of the three lakes, with T4 concentrations being elevated in Lake Okeechobee males compared to Lake Woodruff males. Second, the relationship between body size and hormone concentration was examined using regression analysis. Most notably for steroid hormones, no clear relationship was detected between E2 and total length in Apopka females (r2 0.09, p = 0.54) or between T and total length in Apopka males (r2 = 0.007, p = 0.75). Females from Apopka (r2 = 0.318, p = 0.09) and Okeechobee (r2 = 0.222, p = 0.09) exhibited weak correlations between T3 and total length. Males from Apopka (r2 = 0.015, p = 0.66) and Okeechobee (r2 = 0.128, p = 0.19) showed no correlation between T4 and total length. These results indicate: some of the previously reported abnormalities in steroid hormones of hatchling alligators persist, at least, through the juvenile years; steroid and thyroid hormones are related to body size in juvenile alligators from the reference lake, whereas alligators living in lakes Apopka and Okeechobee experience alterations in circulating thyroid and steroid

  2. Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser

    SciTech Connect

    Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.; Tuberville, Tracey D.

    2016-01-01

    The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3₋), total carbon dioxide (TCO2), base excess (BE), partial pressure of oxygen (PO2), oxygen saturation (sO2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. In conclusion, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood.

  3. Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser

    DOE PAGESBeta

    Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.; Tuberville, Tracey D.

    2016-01-01

    The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressuremore » of carbon dioxide (PCO2), bicarbonate (HCO3₋), total carbon dioxide (TCO2), base excess (BE), partial pressure of oxygen (PO2), oxygen saturation (sO2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. In conclusion, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood.« less

  4. Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser.

    PubMed

    Hamilton, Matthew T; Finger, John W; Winzeler, Megan E; Tuberville, Tracey D

    2016-01-01

    The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3 (-)), total carbon dioxide (TCO2), base excess (BE), partial pressure of oxygen (PO2), oxygen saturation (sO2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F 2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. Lastly, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood. PMID:27382469

  5. Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser

    PubMed Central

    Hamilton, Matthew T.; Finger, John W.; Winzeler, Megan E.; Tuberville, Tracey D.

    2016-01-01

    The assessment of wildlife health has been enhanced by the ability of point-of-care (POC) blood analysers to provide biochemical analyses of non-domesticated animals in the field. However, environmental limitations (e.g. temperature, atmospheric humidity and rain) and lack of reference values may inhibit researchers from using such a device with certain wildlife species. Evaluating the use of alternative sample types, such as plasma, in a POC device may afford researchers the opportunity to delay sample analysis and the ability to use banked samples. In this study, we examined fresh whole blood, fresh plasma and frozen plasma (sample type) pH, partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3−), total carbon dioxide (TCO2), base excess (BE), partial pressure of oxygen (PO2), oxygen saturation (sO2) and lactate concentrations in 23 juvenile American alligators (Alligator mississippiensis) using an i-STAT CG4+ cartridge. Our results indicate that sample type had no effect on lactate concentration values (F2,65 = 0.37, P = 0.963), suggesting that the i-STAT analyser can be used reliably to quantify lactate concentrations in fresh and frozen plasma samples. In contrast, the other seven blood parameters measured by the CG4+ cartridge were significantly affected by sample type. Lastly, we were able to collect blood samples from all alligators within 2 min of capture to establish preliminary reference ranges for juvenile alligators based on values obtained using fresh whole blood. PMID:27382469

  6. Ontogeny of the Middle-Ear Air-Sinus System in Alligator mississippiensis (Archosauria: Crocodylia)

    PubMed Central

    Dufeau, David L.; Witmer, Lawrence M.

    2015-01-01

    Modern crocodylians, including Alligator mississippiensis, have a greatly elaborated system of pneumatic sinuses invading the cranium. These sinuses invade nearly all the bones of the chondrocranium and several bony elements of the splanchnocranium, but patterns of postnatal paratympanic sinus development are poorly understood and documented. Much of crocodylomorph—indeed archosaurian—evolution is characterized by the evolution of various paratympanic air sinuses, the homologies of which are poorly understood due in large part to the fact that individual sinuses tend to become confluent in adults, obscuring underlying patterns. This study seeks to explore the ontogeny of these sinuses primarily to clarify the anatomical relations of the individual sinuses before they become confluent and thus to provide the foundation for later studies testing hypotheses of homology across extant and extinct Archosauria. Ontogeny was assessed using computed tomography in a sample of 13 specimens covering an almost 19-fold increase in head size. The paratympanic sinus system comprises two major inflations of evaginated pharyngeal epithelium: the pharyngotympanic sinus, which communicates with the pharynx via the lateral (true) Eustachian tubes and forms the cavum tympanicum proprium, and the median pharyngeal sinus, which communicates with the pharynx via the median pharyngeal tube. Each of these primary inflations gives rise to a number of secondary inflations that further invade the bones of the skull. The primary sinuses and secondary diverticula are well developed in perinatal individuals of Alligator, but during ontogeny the number and relative volumes of the secondary diverticula are reduced. In addition to describing the morphological ontogeny of this sinus system, we provide some preliminary exploratory analyses of sinus function and allometry, rejecting the hypothesis that changes in the volume of the paratympanic sinuses are simply an allometric function of braincase

  7. Functional specialization and ontogenetic scaling of limb anatomy in Alligator mississippiensis

    PubMed Central

    Allen, Vivian; Elsey, Ruth M; Jones, Nicola; Wright, Jordon; Hutchinson, John R

    2010-01-01

    Crocodylians exhibit a fascinating diversity of terrestrial gaits and limb motions that remain poorly described and are of great importance to understanding their natural history and evolution. Their musculoskeletal anatomy is pivotal to this diversity and yet only qualitative studies of muscle-tendon unit anatomy exist. The relative masses and internal architecture (fascicle lengths and physiological cross-sectional areas) of muscles of the pectoral and pelvic limbs of American alligators (Alligator mississippiensis Daudin 1801) were recorded for an ontogenetic series of wild specimens (n = 15, body masses from 0.5 to 60 kg). The data were analysed by reduced major axis regression to determine scaling relationships with body mass. Physiological cross-sectional areas and therefore muscle force-generating capacity were found to be greater in the extensor (anti-gravity) muscles of the pelvic limb than in the pectoral limb, reflecting how crocodylians differ from mammals in having greater loading of the hindlimbs than the forelimbs. Muscle masses and architecture were generally found to scale isometrically with body mass, suggesting an ontogenetic decrease in terrestrial athleticism. This concurs with the findings of previous studies showing ontogenetic decreases in limb bone length and the general scaling principle of a decline of strength : weight ratios with increasing size in animals. Exceptions to isometric scaling found included positive allometry in fascicle length for extensor musculature of both limbs, suggesting an ontogenetic increase in working range interpreted as increasing postural variability – in particular the major hip extensors – the interpretation of which is complicated by previous described ontogenetic increase of moment arms for these muscles. PMID:20148991

  8. Ontogeny of the Middle-Ear Air-Sinus System in Alligator mississippiensis (Archosauria: Crocodylia).

    PubMed

    Dufeau, David L; Witmer, Lawrence M

    2015-01-01

    Modern crocodylians, including Alligator mississippiensis, have a greatly elaborated system of pneumatic sinuses invading the cranium. These sinuses invade nearly all the bones of the chondrocranium and several bony elements of the splanchnocranium, but patterns of postnatal paratympanic sinus development are poorly understood and documented. Much of crocodylomorph--indeed archosaurian--evolution is characterized by the evolution of various paratympanic air sinuses, the homologies of which are poorly understood due in large part to the fact that individual sinuses tend to become confluent in adults, obscuring underlying patterns. This study seeks to explore the ontogeny of these sinuses primarily to clarify the anatomical relations of the individual sinuses before they become confluent and thus to provide the foundation for later studies testing hypotheses of homology across extant and extinct Archosauria. Ontogeny was assessed using computed tomography in a sample of 13 specimens covering an almost 19-fold increase in head size. The paratympanic sinus system comprises two major inflations of evaginated pharyngeal epithelium: the pharyngotympanic sinus, which communicates with the pharynx via the lateral (true) Eustachian tubes and forms the cavum tympanicum proprium, and the median pharyngeal sinus, which communicates with the pharynx via the median pharyngeal tube. Each of these primary inflations gives rise to a number of secondary inflations that further invade the bones of the skull. The primary sinuses and secondary diverticula are well developed in perinatal individuals of Alligator, but during ontogeny the number and relative volumes of the secondary diverticula are reduced. In addition to describing the morphological ontogeny of this sinus system, we provide some preliminary exploratory analyses of sinus function and allometry, rejecting the hypothesis that changes in the volume of the paratympanic sinuses are simply an allometric function of braincase

  9. Hepatic and renal trace element concentrations in American alligators (Alligator mississippiensis) following chronic dietary exposure to coal fly ash contaminated prey.

    PubMed

    Tuberville, Tracey D; Scott, David E; Metts, Brian S; Finger, John W; Hamilton, Matthew T

    2016-07-01

    Little is known about the propensity of crocodilians to bioaccumulate trace elements as a result of chronic dietary exposure. We exposed 36 juvenile alligators (Alligator mississippiensis) to one of four dietary treatments that varied in the relative frequency of meals containing prey from coal combustion waste (CCW)-contaminated habitats vs. prey from uncontaminated sites, and evaluated tissue residues and growth rates after 12 mo and 25 mo of exposure. Hepatic and renal concentrations of arsenic (As), cadmium (Cd) and selenium (Se) varied significantly among dietary treatment groups in a dose-dependent manner and were higher in kidneys than in livers. Exposure period did not affect Se or As levels but Cd levels were significantly higher after 25 mo than 12 mo of exposure. Kidney As and Se levels were negatively correlated with body size but neither growth rates nor body condition varied significantly among dietary treatment groups. Our study is among the first to experimentally examine bioaccumulation of trace element contaminants in crocodilians as a result of chronic dietary exposure. A combination of field surveys and laboratory experiments will be required to understand the effects of different exposure scenarios on tissue residues, and ultimately link these concentrations with effects on individual health. PMID:27149145

  10. METALS AND METALLOIDS IN TISSUES OF AMERICAN ALLIGATORS IN THREE FLORIDA LAKES

    EPA Science Inventory

    Concentrations of metals and selenium were examined in tissues of American alligators (Alligator mississippiensis) from three lakes in central Florida, in one of which alligators have exhibited reproductive or developmental defects. Our overall objective was to determine whether ...

  11. Thermal acclimation, mitochondrial capacities and organ metabolic profiles in a reptile (Alligator mississippiensis).

    PubMed

    Guderley, Helga; Seebacher, Frank

    2011-01-01

    Reptiles thermoregulate behaviourally, but change their preferred temperature and the optimal temperature for performance seasonally. We evaluated whether the digestive and locomotor systems of the alligator show parallel metabolic adjustments during thermal acclimation. To this end, we allowed juvenile alligators to grow under thermal conditions typical of winter and summer, providing them with seasonally appropriate basking opportunities. Although mean body temperatures of alligators in these groups differed by approximately 10°C, their growth and final anatomic status was equivalent. While hepatic mitochondria isolated from cold-acclimated alligators had higher oxidative capacities at 30°C than those from warm-acclimated alligators, the capacities did not differ at 20°C. Cold acclimation decreased maximal oxidative capacities of muscle mitochondria. For mitochondria from both organs and acclimation groups, palmitate increased oligomycin-inhibited respiration. GDP addition reduced palmitate-uncoupled rates more in liver mitochondria from warm- than cold-acclimated alligators. In muscle mitochondria, carboxyatractyloside significantly reduced palmitate-uncoupled rates. This effect was not changed by thermal acclimation. The aerobic capacity of liver, skeletal muscle and duodenum, as estimated by activities of cytochrome c oxidase (COX), increased with cold acclimation. At acclimation temperatures, the activities of COX and citrate synthase (CS) in these organs were equivalent. By measuring COX and CS in isolated mitochondria and tissue extracts, we estimated that cold acclimation did not change the mitochondrial content in liver, but increased that of muscle. The thermal compensation of growth rates and of the aerobic capacity of the locomotor and digestive systems suggests that alligators optimised metabolic processes for the seasonally altered, preferred body temperature. The precision of this compensatory response exceeds that typically shown by aquatic

  12. POPS IN ALLIGATOR LIVERS FROM LAKE APOPKA, FLORIDA, USA

    EPA Science Inventory

    Reproductive disorders in American alligators (Alligator mississippiensis) inhabiting Lake Apopka, Florida, have been observed for several years. Such disorders are hypothesized to be caused by endocrine disrupting contaminants occurring in the Lake due to pesticide spills and ...

  13. SEASONAL VARIATION IN PLASMA SEX STEROID CONCENTRATION IN JUVENILE ALLIGATORS

    EPA Science Inventory

    Seasonal variation in plasma sex steroid concentrations is common in mature vertebrates, and is occasionally seen in juvenile animals. In this study, we examine the seasonal pattern of sex hormone concentration in juvenile American alligators (Alligator mississippiensis) and make...

  14. Predicting maternal body burdens of organochlorine pesticides from eggs and evidence of maternal transfer in Alligator mississippiensis

    USGS Publications Warehouse

    Rauschenberger, R.H.; Sepulveda, M.S.; Wiebe, J.J.; Szabo, N.J.; Gross, T.S.

    2004-01-01

    Few data exist regarding maternal-embryonal transfer of organochlorine pesticides (OCPs) in reptiles. The objective of the present study was to evaluate maternal transfer of OCPs in American alligators (Alligator mississippiensis) from low-, intermediate-, and high-OCP-exposure sites. Overall, total OCP burdens ranged from less than 0.8 ppb in blood to more than 44,000 ppb in abdominal adipose tissue (wet wt concentrations). Lipid-adjusted ratios of maternal adipose burdens (total OCPs) to yolk burdens were close to one (0.94 ?? 0.31:1), suggesting that animals were in steady state and that OCPs in eggs originated from adipose lipids. In contrast, lipid-adjusted muscle and liver OCP burdens were greater than yolk OCP burdens, suggesting that lipids in muscle were not utilized during oogenesis and that nonlipid liver tissue sequesters OCPs. Predictive equations were derived for several tissues and several OCP analytes with r2 values ranging from 0.40 to 0.99 (p < 0.05). We suggest that yolk burdens are predictive of maternal tissue burdens for certain tissues and OCPs and that certain OCPs are maternally transferred in the American alligator. Furthermore, we suggest that future studies should investigate the applicability of these predictive equations for assessing maternal exposure in other crocodilian species.

  15. Subglottal pressure and fundamental frequency control in contact calls of juvenile Alligator mississippiensis

    PubMed Central

    Riede, Tobias; Tokuda, Isao T.; Farmer, C. G.

    2011-01-01

    SUMMARY Vocalization is rare among non-avian reptiles, with the exception of the crocodilians, the sister taxon of birds. Crocodilians have a complex vocal repertoire. Their vocal and respiratory system is not well understood but appears to consist of a combination of features that are also found in the extremely vocal avian and mammalian taxa. Anatomical studies suggest that the alligator larynx is able to abduct and adduct the vocal folds, but not to elongate or shorten them, and is therefore lacking a key regulator of frequency, yet alligators can modulate fundamental frequency remarkably well. We investigated the morphological and physiological features of sound production in alligators. Vocal fold length scales isometrically across a wide range of alligator body sizes. The relationship between fundamental frequency and subglottal pressure is significant in some individuals at some isolated points, such as call onset and position of maximum fundamental frequency. The relationship is not consistent over large segments of the call. Fundamental frequency can change faster than expected by pressure changes alone, suggesting an active motor pattern controls frequency and is intrinsic to the larynx. We utilized a two-mass vocal fold model to test whether abduction and adduction could generate this motor pattern. The fine-tuned interplay between subglottal pressure and glottal adduction can achieve frequency modulations much larger than those resulting from subglottal pressure variations alone and of similar magnitude, as observed in alligator calls. We conclude that the alligator larynx represents a sound source with only two control parameters (subglottal pressure and vocal fold adduction) in contrast to the mammalian larynx in which three parameters can be altered to modulate frequency (subglottal pressure, vocal fold adduction and length/tension). PMID:21865521

  16. Mortality of American alligators attributed to cannibalism

    USGS Publications Warehouse

    Delany, Michael F.; Woodward, Allan R.; Kiltie, Richard A.; Moore, Clinton T.

    2011-01-01

    Mortality of juvenile (Alligator mississippiensis) attributed to cannibalism on Orange Lake, Florida was examined. Alligator web tags used in mark–recapture studies were found in 12% of 267 stomachs sampled from alligators ≥168 cm TL. Captive alligators retained 76% of force-fed tags during a 588-d tag-retention trial. Models relating the probability of tag recovery to the annual probabilities of juvenile survival, cannibalism, tag retention, adult survival, and adult harvest suggested that cannibalism may on average remove 6–7% of the juvenile alligator population annually. Vulnerability continued to 140 cm TL (age 6–8 yr). Cannibalism of juveniles may serve to regulate the alligator population on Orange Lake. Alligator cannibalism may vary widely among populations, depending on demography and environmental conditions. The role and importance of cannibalism in alligator population dynamics should be more fully assessed and environmental and population factors that influence cannibalism identified to better evaluate management programs.

  17. Alligator diet in relation to alligator mortality on Lake Griffin, FL

    USGS Publications Warehouse

    Rice, A.N.; Ross, J.P.; Woodward, A.R.; Carbonneau, D.A.; Percival, H.F.

    2007-01-01

    Alligator mississippiensis (American Alligators) demonstrated low hatch-rate success and increased adult mortality on Lake Griffin, FL, between 1998 and 2003. Dying Lake Griffin alligators with symptoms of poor motor coordination were reported to show specific neurological impairment and brain lesions. Similar lesions were documented in salmonines that consumed clupeids with high thiaminase levels. Therefore, we investigated the diet of Lake Griffin alligators and compared it with alligator diets from two lakes that exhibited relatively low levels of unexplained alligator mortality to see if consumption of Dorosoma cepedianum (gizzard shad) could be correlated with patterns of mortality. Shad in both lakes Griffin and Apopka had high levels of thiaminase and Lake Apopka alligators were consuming greater amounts of shad relative to Lake Griffin without showing mortality rates similar to Lake Griffin alligators. Therefore, a relationship between shad consumption alone and alligator mortality is not supported.

  18. Growth rates of Chinese and American alligators.

    PubMed

    Herbert, J D; Coulson, T D; Coulson, R A

    2002-04-01

    Growth rates in two closely related species, Alligator mississippiensis (American alligator) and Alligator sinensis (Chinese alligator), were compared under identical conditions for at least 1 year after hatching. When hatched, Chinese alligators were approximately 2/3 the length and approximately 1/2 the weight of American alligator hatchlings. At the end of 1 year of growth in captivity in heated chambers, the Chinese alligators were approximately 1/2 as long and weighed approximately 1/10 as much as American alligator yearlings. When the animals were maintained at 31 degrees C, Chinese alligator food consumption and length gain rates dropped to near zero during autumn and winter and body weights decreased slightly, apparently in response to the change in day length. At constant temperature (31 degrees C), food consumption by American alligators remained high throughout the year. Length gain rates in American alligators decreased slowly as size increased, but were not affected by photoperiod. Daily weight gains in American alligators increased steadily throughout the year. In autumn, provision of artificial light for 18 h a day initially stimulated both length and weight gain in Chinese alligators, but did not affect growth in American alligators. Continuation of the artificial light regimen seemed to cause deleterious effects in the Chinese alligators after several months, however, so that animals exposed to the normal light cycle caught up to and then surpassed the extra-light group in size. Even after removal of the artificial light, it was several months before these extra-light animals reverted to a normal growth pattern. These findings may be of interest to those institutions engaged in captive growth programs intended to provide animals for reintroduction to the wild or to protected habitat. PMID:11897202

  19. Histological organization and its relationship to function in the femur of Alligator mississippiensis

    PubMed Central

    Lee, Andrew H

    2004-01-01

    Histological analysis of a growth series of alligator femora tests the correlation between strain milieu and microstructure. From mid-diaphyseal cross-sections of these femora (n = 7), vascular canal orientation and density as well as collagen fibre organization were recorded. Throughout ontogeny, the proportion of transverse–spiral (TS) collagen in the dorsal cortex is significantly greater than it is in the ventral cortex (P = 0.008). This regional difference in the proportion of TS collagen is correlated with a regional difference in the state of peak principal strain (compressive or tensile). Nevertheless, the predominant orientation of collagen fibres is longitudinal, which is inconsistent with biomechanical hypotheses that involve peak principal or shear strains. Although the density and orientation of vascular canals do not show significant regional differences (P = 0.26 and P = 0.26, respectively), as with collagen orientation, the vascular canal orientation is predominantly longitudinal. The longitudinal organization of both the vascular canals and the collagen fibres is probably a consequence of longitudinal shifting of subperiosteal osteoid during femoral lengthening. When taken together, these data suggest that growth dynamics is the dominant influence on the histological organization of primary bony tissues in alligator femora. PMID:15032909

  20. New insight into the anatomy of the hyolingual apparatus of Alligator mississippiensis and implications for reconstructing feeding in extinct archosaurs.

    PubMed

    Li, Zhiheng; Clarke, Julia A

    2015-07-01

    Anatomical studies of the cranium of crocodilians motivated by an interest in its function in feeding largely focused on bite force, the jaw apparatus and associated muscles innervated by the trigeminal nerve. However, the ossified and cartilaginous elements of the hyoid and the associated hyolingual muscles, innervated by the facial, hypoglossal and glossopharyngeal nerves, received much less attention. Crocodilians are known to retain what are ancestrally the 'Rhythmic Hyobranchial Behaviors' such as buccal oscillation, but show diminished freedom and movement for the hyobranchial apparatus and the tongue in food transport and manipulation. Feeding among crocodilians, generally on larger prey items than other reptilian outgroups, involves passive transport of the food within the mouth. The tongue in extant crocodilians is firmly attached to the buccal floor and shows little movement during feeding. Here, we present a detailed anatomical description of the myology of the hyolingual apparatus of Alligator mississippiensis, utilizing contrast-enhanced micro-computed tomography and dissection. We construct the first three-dimensional (3D) description of hyolingual myology in Alligator mississippiensis and discuss the detailed implications of these data for our understanding of hyolingual muscle homology across Reptilia. These anatomical data and an evaluation of the fossil record of hyoid structures also shed light on the evolution of feeding in Reptilia. Simplification of the hyoid occurs early in the evolution of archosaurs. A hyoid with only one pair of ceratobranchials and a weakly ossified or cartilaginous midline basihyal is ancestral to Archosauriformes. The comparison with non-archosaurian reptilian outgroup demonstrates that loss of the second set of ceratobranchials as well as reduced ossification in basihyal occurred prior to the origin of crown-clade archosaurs, crocodilians and birds. Early modification in feeding ecology appears to characterize the

  1. Persistent Organochlorine Pesticides and their Metabolites in Alligator Livers from Lakes Apopka and Woodruff, Florida, USA

    EPA Science Inventory

    Reproductive disorders in American alligators (Alligator mississippiensis) inhabiting Lake Apopka, Florida, have been observed for several years. Such disorders are hypothesized to be caused by endocrine disrupting contaminants occurring in the Lake due to pesticide spills and ...

  2. Laser ablation ICP-MS analysis of the radial distribution of lead in the femur of Alligator mississippiensis.

    PubMed

    Seltzer, Michael D; Lance, Valentine A; Elsey, Ruth M

    2006-06-15

    A laser ablation ICP-MS technique has been used to examine the radial distribution of lead in transverse sections of alligator femur. Annual bone growth in the femur results in the deposition of incremental layers of calcified tissue at the periphery of existing bone. Patterns of lead concentration within these layers provide a record of time-dependent accumulation from which exposure history can potentially be deduced. Femur specimens obtained from captive-reared alligators exhibited levels of lead accumulation that were entirely consistent with previously documented clinical signs of lead intoxication. In contrast, femurs obtained from wild alligators contained only minor amounts of lead that were likely accumulated as a result of incidental exposure. PMID:15982720

  3. Organizational Changes to Thyroid Regulation in Alligator mississippiensis: Evidence for Predictive Adaptive Responses

    PubMed Central

    Boggs, Ashley S. P.; Lowers, Russell H.; Cloy-McCoy, Jessica A.; Guillette, Louis J.

    2013-01-01

    During embryonic development, organisms are sensitive to changes in thyroid hormone signaling which can reset the hypothalamic-pituitary-thyroid axis. It has been hypothesized that this developmental programming is a ‘predictive adaptive response’, a physiological adjustment in accordance with the embryonic environment that will best aid an individual's survival in a similar postnatal environment. When the embryonic environment is a poor predictor of the external environment, the developmental changes are no longer adaptive and can result in disease states. We predicted that endocrine disrupting chemicals (EDCs) and environmentally-based iodide imbalance could lead to developmental changes to the thyroid axis. To explore whether iodide or EDCs could alter developmental programming, we collected American alligator eggs from an estuarine environment with high iodide availability and elevated thyroid-specific EDCs, a freshwater environment contaminated with elevated agriculturally derived EDCs, and a reference freshwater environment. We then incubated them under identical conditions. We examined plasma thyroxine and triiodothyronine concentrations, thyroid gland histology, plasma inorganic iodide, and somatic growth at one week (before external nutrition) and ten months after hatching (on identical diets). Neonates from the estuarine environment were thyrotoxic, expressing follicular cell hyperplasia (p = 0.01) and elevated plasma triiodothyronine concentrations (p = 0.0006) closely tied to plasma iodide concentrations (p = 0.003). Neonates from the freshwater contaminated site were hypothyroid, expressing thyroid follicular cell hyperplasia (p = 0.01) and depressed plasma thyroxine concentrations (p = 0.008). Following a ten month growth period under identical conditions, thyroid histology (hyperplasia p = 0.04; colloid depletion p = 0.01) and somatic growth (body mass p<0.0001; length p = 0.02) remained altered among the

  4. Post-hatching development of mitochondrial function, organ mass and metabolic rate in two ectotherms, the American alligator (Alligator mississippiensis) and the common snapping turtle (Chelydra serpentina).

    PubMed

    Sirsat, Sarah K G; Sirsat, Tushar S; Price, Edwin R; Dzialowski, Edward M

    2016-01-01

    The ontogeny of endothermy in birds is associated with disproportionate growth of thermogenic organs and increased mitochondrial oxidative capacity. However, no similar study has been made of the development of these traits in ectotherms. For comparison, we therefore investigated the metabolism, growth and muscle mitochondrial function in hatchlings of a turtle and a crocodilian, two ectotherms that never develop endothermy. Metabolic rate did not increase substantially in either species by 30 days post-hatching. Yolk-free body mass and heart mass did not change through 30 days in alligators and heart mass was a constant proportion of body mass, even after 1 year. Yolk-free body mass and liver mass grew 36% and 27%, respectively, in turtles during the first 30 days post-hatch. The mass-specific oxidative phosphorylation capacity of mitochondria, assessed using permeabilized muscle fibers, increased by a non-significant 47% in alligator thigh and a non-significant 50% in turtle thigh over 30 days, but did not increase in the heart. This developmental trajectory of mitochondrial function is slower and shallower than that previously observed in ducks, which demonstrate a 90% increase in mass-specific oxidative phosphorylation capacity in thigh muscles over just a few days, a 60% increase in mass-specific oxidative phosphorylation capacity of the heart over a few days, and disproportionate growth of the heart and other organs. Our data thus support the hypothesis that these developmental changes in ducks represent mechanistic drivers for attaining endothermy. PMID:26962048

  5. Post-hatching development of mitochondrial function, organ mass and metabolic rate in two ectotherms, the American alligator (Alligator mississippiensis) and the common snapping turtle (Chelydra serpentina)

    PubMed Central

    Sirsat, Sarah K. G.; Sirsat, Tushar S.; Price, Edwin R.; Dzialowski, Edward M.

    2016-01-01

    ABSTRACT The ontogeny of endothermy in birds is associated with disproportionate growth of thermogenic organs and increased mitochondrial oxidative capacity. However, no similar study has been made of the development of these traits in ectotherms. For comparison, we therefore investigated the metabolism, growth and muscle mitochondrial function in hatchlings of a turtle and a crocodilian, two ectotherms that never develop endothermy. Metabolic rate did not increase substantially in either species by 30 days post-hatching. Yolk-free body mass and heart mass did not change through 30 days in alligators and heart mass was a constant proportion of body mass, even after 1 year. Yolk-free body mass and liver mass grew 36% and 27%, respectively, in turtles during the first 30 days post-hatch. The mass-specific oxidative phosphorylation capacity of mitochondria, assessed using permeabilized muscle fibers, increased by a non-significant 47% in alligator thigh and a non-significant 50% in turtle thigh over 30 days, but did not increase in the heart. This developmental trajectory of mitochondrial function is slower and shallower than that previously observed in ducks, which demonstrate a 90% increase in mass-specific oxidative phosphorylation capacity in thigh muscles over just a few days, a 60% increase in mass-specific oxidative phosphorylation capacity of the heart over a few days, and disproportionate growth of the heart and other organs. Our data thus support the hypothesis that these developmental changes in ducks represent mechanistic drivers for attaining endothermy. PMID:26962048

  6. Elemental Levels Analyzed by PIXE in Florida Alligators

    SciTech Connect

    Kuharik, J.C.; Kravchenko, I.I.; Dunnam, F.E.; Rinsvelt, H.A. van; Ross, J.P.

    2003-08-26

    Unusual and alarming mortality of alligators (Alligator mississippiensis) has been reported from Lake Griffin, Florida, where almost 400 dead alligators have been observed since 1997. In addition, the hatch rate for alligator eggs around Lake Griffin fell below 10% and remains low (30-45%) while the normal hatch rate is typically 80%. Standard diagnostic methods have been ineffective in determining the cause of the phenomenon. Many possibilities have been considered including pollutants, nutrition, and toxic algae. Particle Induced X-ray Emission (PIXE) analysis is highly suitable for investigating concentrations of a wide range of elements in animal tissue. Liver, kidney and spinal cord tissues from healthy and sick alligators have been analyzed by PIXE for elemental content. Initial results showed positive correlation between certain elements and neural impairment and morbidity of alligators in Lake Griffin, but have failed to prove significant.

  7. Elemental Levels Analyzed by PIXE in Florida Alligators

    NASA Astrophysics Data System (ADS)

    Kuharik, J. C.; Kravchenko, I. I.; Dunnam, F. E.; Van Rinsvelt, H. A.; Ross, J. P.

    2003-08-01

    Unusual and alarming mortality of alligators (Alligator mississippiensis) has been reported from Lake Griffin, Florida, where almost 400 dead alligators have been observed since 1997. In addition, the hatch rate for alligator eggs around Lake Griffin fell below 10% and remains low (30-45%) while the normal hatch rate is typically 80%. Standard diagnostic methods have been ineffective in determining the cause of the phenomenon. Many possibilities have been considered including pollutants, nutrition, and toxic algae. Particle Induced X-ray Emission (PIXE) analysis is highly suitable for investigating concentrations of a wide range of elements in animal tissue. Liver, kidney and spinal cord tissues from healthy and sick alligators have been analyzed by PIXE for elemental content. Initial results showed positive correlation between certain elements and neural impairment and morbidity of alligators in Lake Griffin, but have failed to prove significant.

  8. The utility of captive animals in actualistic research: A geometric morphometric exploration of the tooth row of Alligator mississippiensis suggesting ecophenotypic influences and functional constraints.

    PubMed

    Drumheller, Stephanie K; Wilberg, Eric W; Sadleir, Rudyard W

    2016-07-01

    Captive broad snouted crocodylians are generally thought to have wider, shorter rostra than their wild counterparts. Interpreted to reflect morphological change in response to the conditions of captivity, this qualitative pattern could affect the utility of these animals in a variety of fields of research. However, due to relative ease of access and availability of life history data, captive animals are often utilized in actualistic research. Thus, this issue should be addressed in more detail. Here we explore snout shape variation between captive and wild members of Alligator mississippiensis using two-dimensional (2D) morphometric techniques. Several landmark schemesare used to assess the utility of different aspects of morphology in distinguishing the groups. While statistical analyses consistently differentiated between the groups, the area of morphospace occupied by wild members of A. mississippiensis generally overlapped with the larger area encompassing the captive specimens. This indicates that the captive condition is not as uniform as previously thought and instead encompasses a large spectrum of morphologies, ranging from the stereotypical broad, shortened snouts to outlines that are indistinguishable from the wild morphotype. These results align well with the interpretation that this change reflects an extreme example of ecophenotypy, since ranched, farmed, or zoo organisms are held in an array of enclosures, ranging from indoor, climate controlled pens to outdoor, more natural areas. This variation in environments should be reflected in different reactions to the animals' surroundings, resulting in a broad spectrum of morphotypes. While wild specimens are still preferred, especially for fine scale analyses, these results indicate that not all captive members of A. mississippiensis exhibit the extreme morphological alterations often cited in the literature. Weighing the conditions in which the animals are held and exploring the possibility of

  9. TEMPORAL AND SPATIAL VARIATION IN PLASMA THYROXINE (T4) CONCENTRATIONS IN JUVENILE ALLIGATORS COLLECTED FROM LAKE OKEECHOBEE AND THE NORTHERN EVERGLADES, FLORIDA, USA

    EPA Science Inventory

    We examined variation in plasma thyroxine (T4) in juvenile American alligators (Alligator mississippiensis) collected from three sites within the Kissimmee River drainage basin (FL, USA). Based on historical sediment data, Moonshine Bay served as the low contaminant exposure site...

  10. Hexavalent chromium is cytotoxic and genotoxic to American alligator cells.

    PubMed

    Wise, Sandra S; Wise, Catherine; Xie, Hong; Guillette, Louis J; Zhu, Cairong; Wise, John Pierce; Wise, John Pierce

    2016-02-01

    Metals are a common pollutant in the aquatic ecosystem. With global climate change, these levels are anticipated to rise as lower pH levels allow sediment bound metals to be released. The American alligator (Alligator mississippiensis) is an apex predator in the aquatic ecosystem and is considered a keystone species; as such it serves as a suitable monitor for localized pollution. One metal of increasing concern is hexavalent chromium (Cr(VI)). It is present in the aquatic environment and is a known human carcinogen and reproductive toxicant. We measured the cytotoxicity and genotoxicity of Cr(VI) in American alligator cells derived from scute tissue. We found that particulate and soluble Cr(VI) are both cytotoxic and genotoxic to alligator cells in a concentration-dependent manner. These data suggest that alligators may be used as a model for assessing the effects of environmental Cr(VI) contamination as well as for other metals of concern. PMID:26730726

  11. A big alligator snacks on a smaller alligator

    NASA Technical Reports Server (NTRS)

    1998-01-01

    A large alligator attacks and eats a smaller one in a natural display of cannibalism. Although this event has been observed infrequently by Kennedy Space Center's staff photographers, it is common feeding behavior among the wild alligator population on the space center. Alligators are carnivorous and will eat any living thing that crosses their paths and is small enough for them to kill. For this reason, it is dangerous to feed wild alligators, and in Florida, it is also illegal. Kennedy Space Center is located on the Merritt Island National Wildlife Refuge which is operated by the U.S. Fish and Wildlife Service.

  12. The 'Angry Alligator'

    NASA Technical Reports Server (NTRS)

    1966-01-01

    The Augmented Target Docking Adapter (ATDA) as seen from the Gemini 9 spacecraft during one of their three rendezvous in space. The ATDA and Gemini 9 spacecraft are 66.5 ft. apart. Failure of the docking adapter protective cover to fully separate on the ATDA prevented the docking of the two spacecraft. The ATDA was described by the Gemini 9 crew as an 'angry alligator.'

  13. Hypoxic alligator embryos: chronic hypoxia, catecholamine levels and autonomic responses of in ovo alligators.

    PubMed

    Eme, John; Altimiras, Jordi; Hicks, James W; Crossley, Dane A

    2011-11-01

    Hypoxia is a naturally occurring environmental challenge for embryonic reptiles, and this is the first study to investigate the impact of chronic hypoxia on the in ovo development of autonomic cardiovascular regulation and circulating catecholamine levels in a reptile. We measured heart rate (f(H)) and chorioallantoic arterial blood pressure (MAP) in normoxic ('N21') and hypoxic-incubated ('H10'; 10% O(2)) American alligator embryos (Alligator mississippiensis) at 70, 80 and 90% of development. Embryonic alligator responses to adrenergic blockade with propranolol and phentolamine were very similar to previously reported responses of embryonic chicken, and demonstrated that embryonic alligator has α and β-adrenergic tone over the final third of development. However, adrenergic tone originates entirely from circulating catecholamines and is not altered by chronic hypoxic incubation, as neither cholinergic blockade with atropine nor ganglionic blockade with hexamethonium altered baseline cardiovascular variables in N21 or H10 embryos. In addition, both atropine and hexamethonium injection did not alter the generally depressive effects of acute hypoxia - bradycardia and hypotension. However, H10 embryos showed significantly higher levels of noradrenaline and adrenaline at 70% of development, as well as higher noradrenaline at 80% of development, suggesting that circulating catecholamines reach maximal levels earlier in incubation for H10 embryos, compared to N21 embryos. Chronically elevated levels of catecholamines may alter the normal balance between α and β-adrenoreceptors in H10 alligator embryos, causing chronic bradycardia and hypotension of H10 embryos measured in normoxia. PMID:21798363

  14. The impact of bone and suture material properties on mandibular function in Alligator mississippiensis: testing theoretical phenotypes with finite element analysis

    PubMed Central

    Reed, David A; Porro, Laura B; Iriarte-Diaz, Jose; Lemberg, Justin B; Holliday, Casey M; Anapol, Fred; Ross, Callum F

    2011-01-01

    Abstract The functional effects of bone and suture stiffness were considered here using finite element models representing three different theoretical phenotypes of an Alligator mississippiensis mandible. The models were loaded using force estimates derived from muscle architecture in dissected specimens, constrained at the 18th and 19th teeth in the upper jaw and 19th tooth of the lower jaw, as well as at the quadrate-articular joint. Stiffness was varied systematically in each theoretical phenotype. The three theoretical phenotypes included: (i) linear elastic isotropic bone of varying stiffness and no sutures; (ii) linear elastic orthotropic bone of varying stiffness with no sutures; and (iii) linear elastic isotropic bone of a constant stiffness with varying suture stiffness. Variation in the isotropic material properties of bone primarily resulted in changes in the magnitude of principal strain. By comparison, variation in the orthotropic material properties of bone and isotropic material properties of sutures resulted in: a greater number of bricks becoming either more compressive or more tensile, changing between being either dominantly compressive or tensile, and having larger changes in the orientation of maximum principal strain. These data indicate that variation in these model properties resulted in changes to the strain regime of the model, highlighting the importance of using biologically verified material properties when modeling vertebrate bones. When bones were compared within each set, the response of each to changing material properties varied. In two of the 12 bones in the mandible, varied material properties within sutures resulted in a decrease in the magnitude of principal strain in bricks adjacent to the bone/suture interface and decreases in stored elastic energy. The varied response of the mandibular bones to changes in suture stiffness highlights the importance of defining the appropriate functional unit when addressing relationships of

  15. The impact of bone and suture material properties on mandibular function in Alligator mississippiensis: testing theoretical phenotypes with finite element analysis.

    PubMed

    Reed, David A; Porro, Laura B; Iriarte-Diaz, Jose; Lemberg, Justin B; Holliday, Casey M; Anapol, Fred; Ross, Callum F

    2011-01-01

    The functional effects of bone and suture stiffness were considered here using finite element models representing three different theoretical phenotypes of an Alligator mississippiensis mandible. The models were loaded using force estimates derived from muscle architecture in dissected specimens, constrained at the 18th and 19th teeth in the upper jaw and 19th tooth of the lower jaw, as well as at the quadrate-articular joint. Stiffness was varied systematically in each theoretical phenotype. The three theoretical phenotypes included: (i) linear elastic isotropic bone of varying stiffness and no sutures; (ii) linear elastic orthotropic bone of varying stiffness with no sutures; and (iii) linear elastic isotropic bone of a constant stiffness with varying suture stiffness. Variation in the isotropic material properties of bone primarily resulted in changes in the magnitude of principal strain. By comparison, variation in the orthotropic material properties of bone and isotropic material properties of sutures resulted in: a greater number of bricks becoming either more compressive or more tensile, changing between being either dominantly compressive or tensile, and having larger changes in the orientation of maximum principal strain. These data indicate that variation in these model properties resulted in changes to the strain regime of the model, highlighting the importance of using biologically verified material properties when modeling vertebrate bones. When bones were compared within each set, the response of each to changing material properties varied. In two of the 12 bones in the mandible, varied material properties within sutures resulted in a decrease in the magnitude of principal strain in bricks adjacent to the bone/suture interface and decreases in stored elastic energy. The varied response of the mandibular bones to changes in suture stiffness highlights the importance of defining the appropriate functional unit when addressing relationships of

  16. Estimating sighting proportions of American alligator nests during helicopter survey

    USGS Publications Warehouse

    Rice, Kenneth G.; Percival, H. Franklin; Woodward, Allan R.

    2000-01-01

    Proportions of American alligator (Alligator mississippiensis) nests sighted during aerial survey in Florida were estimated based upon multiple surveys by different observers. We compared sighting proportions across habitats, nesting seasons, and observer experience levels. The mean sighting proportion across all habitats and years was 0.736 (SE=0.024). Survey counts corrected by the mean sighting proportion reliably predicted total nest counts (7?2=0.933). Sighting proportions did not differ by habitat type (P=0.668) or year P=0.328). Experienced observers detected a greater proportion of nests (P<0.0001) than did either less experienced or inexperienced observers. Reliable estimates of nest abundance can be derived from aerial counts of alligator nests when corrected by the appropriate sighting proportion.

  17. Spatial and temporal variability in estuary habitat use by American alligators

    USGS Publications Warehouse

    Fujisaki, Ikuko; Hart, Kristen M.; Cherkiss, Michael S.; Mazzotti, Frank J.; Beauchamp, Jeffrey S.; Jeffery, Brian M.; Brandt, Laura A.

    2016-01-01

    Estuarine habitat occupied by Alligator mississippiensis, a primarily freshwater species, is spatially and temporally heterogeneous largely due to a salinity gradient that fluctuates. Using long-term night light survey data, we examined seasonal patterns in alligators’ habitat use by size classes in midstream and downstream estuary zones of Shark River, Everglades National Park, in southern Florida. We observed predominantly large-sized alligators (total length ≥ 1.75 m); observations of alligators in the small size classes (0.5 m ≤ total length < 1.25 m) were rare especially in the higher-salinity downstream zone. The density of alligators in the downstream zone was lower than that of the midstream zone during the dry season when salinity increases due to reduced precipitation. Conversely, the density of the large size alligators was higher in the downstream zone than in the midstream zone during the wet season, likely because of reduced salinity. We also found a significant declining trend over time in the number of alligators in the dry season, which coincides with the reported decline in alligator relative density in southern Florida freshwater wetlands. Our results indicated high adaptability of alligators to the fluctuating habitat conditions. Use of estuaries by alligators is likely driven in part by physiology and possibly by reproductive cycle, and our results supported their opportunistic use of estuary habitat and ontogenetic niche shifts.

  18. Umbilical scarring in hatchling American alligators

    USGS Publications Warehouse

    Wiebe, J.J.; Sepulveda, M.S.; Buckland, J.E.; Anderson, S.R.; Gross, T.S.

    2004-01-01

    Umbilical scarring is the presence of excess scar tissue deposited between abdominal dermal layers at the site of yolk sac absorption in hatchling American alligators (Alligator mississippiensis). The presence of this dermal condition plays a key evaluatory role in the overall quality and subsequent value for various commercial leather products. Despite the prevalent nature of this condition, currently the industry has no standardized protocols for its quantification. The objectives of this study were to examine the relationship between hatchling weight and age and incidence of umbilical scarring and to develop a quantifiable and reproducible technique to measure this dermal condition in hatchling American alligators. Thirty eggs from each of nine clutches were incubated in two separate incubators at different facilities and hatchling umbilical scarring was measured at 2 and 10 days of age using digital calipers. Umbilical area was calculated by multiplying umbilical length times umbilical width. There was a significant effect of both age and clutch on umbilical area (overall decline of 64%) by 10 days post-hatch. However, only five of the nine clutches utilized expressed a noticeable decline in the size of this dermal condition (range 67-74%). We had hypothesized that larger hatchlings would have larger umbilical areas and a slower rate of improvement in this condition during the first few days post-hatch. The differences in umbilical area and percent decline with age across clutches, however, were not associated with differences in initial hatchling weights. Within clutches and time periods, hatchling weight had no significant effect on the size and/or rate of decline of this condition. ?? 2004 Published by Elsevier B.V.

  19. Alligators in the Sewers? Really?

    ERIC Educational Resources Information Center

    Egbert, Joy

    2009-01-01

    A large number of alligators, flushed down toilets as babies, have grown up and proliferated in the bowels of New York City. Over the years, they have grown in number and size and frequently terrorize those foolish enough to visit the subways. This tale has been making its way around the Internet ever since there's been an Internet. It's wild…

  20. Biomonitoring Heavy Metal Pollution Using an Aquatic Apex Predator, the American Alligator, and Its Parasites.

    PubMed

    Tellez, Marisa; Merchant, Mark

    2015-01-01

    Monitoring the bioaccumulation of chemical elements within various organismal tissues has become a useful tool to survey current or chronic levels of heavy metal exposure within an environment. In this study, we compared the bioaccumulations of As, Cd, Cu, Fe, Pb, Se, and Zn between the American alligator, Alligator mississippiensis, and its parasites in order to establish their use as bioindicators of heavy metal pollution. Concomitant with these results, we were interested to determine if parasites were more sensitive bioindicators of heavy metals relative to alligators. We found parasites collectively accumulated higher levels of As, Cu, Se, and Zn in comparison to their alligator hosts, whereas Fe, Cd, and Pb concentrations were higher in alligators. Interestingly, Fe levels were significantly greater in intestinal trematodes than their alligator hosts when analyzed independently from other parasitic taxa. Further analyses showed alligator intestinal trematodes concentrated As, Cu, Fe, Se, and Zn at significantly higher levels than intestinal nematodes and parasites from other organs. However, pentastomids also employed the role as a good biomagnifier of As. Interestingly, parasitic abundance decreased as levels of As increased. Stomach and intestinal nematodes were the poorest bioaccumulators of metals, yet stomach nematodes showed their ability to concentrate Pb at orders of magnitude higher in comparison to other parasites. Conclusively, we suggest that parasites, particularly intestinal trematodes, are superior biomagnifiers of As, Cu, Se, and Zn, whereas alligators are likely good biological indicators of Fe, Cd, and Pb levels within the environment. PMID:26555363

  1. Biomonitoring Heavy Metal Pollution Using an Aquatic Apex Predator, the American Alligator, and Its Parasites

    PubMed Central

    Tellez, Marisa; Merchant, Mark

    2015-01-01

    Monitoring the bioaccumulation of chemical elements within various organismal tissues has become a useful tool to survey current or chronic levels of heavy metal exposure within an environment. In this study, we compared the bioaccumulations of As, Cd, Cu, Fe, Pb, Se, and Zn between the American alligator, Alligator mississippiensis, and its parasites in order to establish their use as bioindicators of heavy metal pollution. Concomitant with these results, we were interested to determine if parasites were more sensitive bioindicators of heavy metals relative to alligators. We found parasites collectively accumulated higher levels of As, Cu, Se, and Zn in comparison to their alligator hosts, whereas Fe, Cd, and Pb concentrations were higher in alligators. Interestingly, Fe levels were significantly greater in intestinal trematodes than their alligator hosts when analyzed independently from other parasitic taxa. Further analyses showed alligator intestinal trematodes concentrated As, Cu, Fe, Se, and Zn at significantly higher levels than intestinal nematodes and parasites from other organs. However, pentastomids also employed the role as a good biomagnifier of As. Interestingly, parasitic abundance decreased as levels of As increased. Stomach and intestinal nematodes were the poorest bioaccumulators of metals, yet stomach nematodes showed their ability to concentrate Pb at orders of magnitude higher in comparison to other parasites. Conclusively, we suggest that parasites, particularly intestinal trematodes, are superior biomagnifiers of As, Cu, Se, and Zn, whereas alligators are likely good biological indicators of Fe, Cd, and Pb levels within the environment. PMID:26555363

  2. Estimating trends in alligator populations from nightlight survey data

    USGS Publications Warehouse

    Fujisaki, Ikuko; Mazzotti, F.J.; Dorazio, R.M.; Rice, K.G.; Cherkiss, M.; Jeffery, B.

    2011-01-01

    Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of American alligators (Alligator mississippiensis) in subareas of Everglades wetlands in Florida using nightlight survey data. During 2001-2008, there were declining trends in abundance of small and/or medium sized animals in a majority of subareas, whereas abundance of large sized animals had either demonstrated an increased or unclear trend. For small and large sized class animals, estimated detection probability declined as water depth increased. Detection probability of small animals was much lower than for larger size classes. The declining trend of smaller alligators may reflect a natural population response to the fluctuating environment of Everglades wetlands under modified hydrology. It may have negative implications for the future of alligator populations in this region, particularly if habitat conditions do not favor recruitment of offspring in the near term. Our study provides a foundation to improve inferences made from nightlight surveys of other crocodilian populations. ?? 2011 US Government.

  3. Estimating trends in alligator populations from nightlight survey data

    USGS Publications Warehouse

    Fujisaki, Ikuko; Mazzotti, Frank J.; Dorazio, Robert M.; Rice, Kenneth G.; Cherkiss, Michael; Jeffery, Brian

    2011-01-01

    Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of American alligators (Alligator mississippiensis) in subareas of Everglades wetlands in Florida using nightlight survey data. During 2001–2008, there were declining trends in abundance of small and/or medium sized animals in a majority of subareas, whereas abundance of large sized animals had either demonstrated an increased or unclear trend. For small and large sized class animals, estimated detection probability declined as water depth increased. Detection probability of small animals was much lower than for larger size classes. The declining trend of smaller alligators may reflect a natural population response to the fluctuating environment of Everglades wetlands under modified hydrology. It may have negative implications for the future of alligator populations in this region, particularly if habitat conditions do not favor recruitment of offspring in the near term. Our study provides a foundation to improve inferences made from nightlight surveys of other crocodilian populations.

  4. Jumping the Alligators in the Ditch.

    ERIC Educational Resources Information Center

    Barber, Rims

    Poor black young people in rural Mississippi contemplate their schooling with the same feelings as their friends who dare to jump the local ditches filled with alligators: the odds are against escaping the alligators, and the advantages of getting to the far side are not very apparent. Living in conditions of extreme poverty, these young people…

  5. Survival of young American alligators on a Florida lake

    USGS Publications Warehouse

    Woodward, A.R.; Hines, T.C.; Abercrombie, C.L.; Nichols, J.D.

    1987-01-01

    A capture-recapture study was conducted on Orange Lake, Florida, from 1979 through 1984 to estimate survival rates of young in an American alligator (Alligator mississippiensis) populations. Hatchlings remained together in sibling groups (pods) for at least their 1st year and then began to disperse during their 2nd spring and summer. Mortality through mid-November of their 1st year was negligible. Jolly-Seber (JS) survival estimates of hatchlings for 6 and 12 months were 76 and 41%, respectively. The 2-year JS estimate for the 1980 cohort was 8%. Minimum-Known-Alive (MKA) survival values were 72 and 46% of JS estimates for 6 months and 1 year of age. Survival during the 2nd 6 months of life (spring-summer) tended to be lower than survival during the 1st 6 months (fall-winter).

  6. Concentrations of contaminants in muscle of the American alligator in Florida

    SciTech Connect

    Delany, M.F.; Bell, J.U.; Sundlof, S.F.

    1988-01-01

    Samples of tail muscle from 32 American alligators (Alligator mississippiensis) in Florida were analyzed for contaminant concentrations to provide preliminary information on the potential public health hazard of meat consumption. Detectable levels were found for eight metals; copper, zinc, iron, chromium, mercury, lead, cadmium and arsenic. Mean residue was highest for mercury (geometric mean = 0.61 ppm). DDE, DDD, DDT, dieldrin, heptachlor epoxide, lindane, and PCB's were found. Mean residue concentrations were compared by lake. Alligators appeared to be suitable monitors of environmental pollution. Concentrations of contaminants found in these animals probably pose little threat to public health. However, recommendations must await analysis of larger sample sizes and information on amount and frequency of meat consumption. Alligators killed for human consumption should continue to be monitored for contaminant residues.

  7. Use of alligator hole abundance and occupancy rate as indicators for restoration of a human-altered wetland

    USGS Publications Warehouse

    Fujisaki, Ikuko; Mazzotti, Frank J.; Hart, Kristen M.; Rice, Kenneth G.; Ogurcak, Danielle; Rochford, Michael; Jeffery, Brian M.; Brandt, Laura A.; Cherkiss, Michael S.

    2012-01-01

    Use of indicator species as a measure of ecosystem conditions is an established science application in environmental management. Because of its role in shaping wetland systems, the American alligator (Alligator mississippiensis) is one of the ecological indicators for wetland restoration in south Florida, USA. We conducted landscape-level aerial surveys of alligator holes in two different habitats in a wetland where anthropogenic modification of surface hydrology has altered the natural system. Alligator holes were scarcer in an area where modified hydrology caused draining and frequent dry-downs compared to another area that maintains a functional wetland system. Lower abundance of alligator holes indicates lack of alligator activities, lower overall species diversity, and lack of dry-season aquatic refugia for other organisms. The occupancy rate of alligator holes was lower than the current restoration target for the Everglades, and was variable by size class with large size-class alligators predominantly occupying alligator holes. This may indicate unequal size-class distribution, different habitat selection by size classes, or possibly a lack of recruitment. Our study provides pre-restoration baseline information about one indicator species for the Everglades. Success of the restoration can be assessed via effective synthesis of information derived by collective research efforts on the entire suite of selected ecological indicators.

  8. On the variability of alligator sex ratios

    USGS Publications Warehouse

    Nichols, J.D.; Chabreck, R.H.

    1980-01-01

    Samples of alligators from wild and 'farm' populations exhibited disproportionate sex ratios. Males predominated among young alligators from wild populations, whereas females were much more abundant than males in the farm population, where resources were superabundant. These results and other considerations lead us to hypothesize that environmental factors influence sex determination in alligators. During favorable environmental conditions natural selection is expected to favor a preponderance of the sex whose individuals exhibit the greater environmentally associated variation in relative fitness. We hypothesize that environmentally associated variation in age at sexual maturity of females produces sufficient variation in relative fitness of females to result in selection for low sex ratios during periods of resource abundance.

  9. Comparison of metabolic substrates in alligators and several birds of prey.

    PubMed

    Sweazea, Karen L; McMurtry, John P; Elsey, Ruth M; Redig, Patrick; Braun, Eldon J

    2014-08-01

    On average, avian blood glucose concentrations are 1.5-2 times those of mammals of similar mass and high concentrations of insulin are required to lower blood glucose. Whereas considerable data exist for granivorous species, few data are available for plasma metabolic substrate and glucoregulatory hormone concentrations for carnivorous birds and alligators. Birds and mammals with carnivorous diets have higher metabolic rates than animals consuming diets with less protein whereas alligators have low metabolic rates. Therefore, the present study was designed to compare substrate and glucoregulatory hormone concentrations in several birds of prey and a phylogenetically close relative of birds, the alligator. The hypothesis was that the combination of carnivorous diets and high metabolic rates favored the evolution of greater protein and fatty acid utilization leading to insulin resistance and high plasma glucose concentrations in carnivorous birds. In contrast, it was hypothesized that alligators would have low substrate utilization attributable to a low metabolic rate. Fasting plasma substrate and glucoregulatory hormone concentrations were compared for bald eagles (Haliaeetus leucocephalus), great horned owls (Bubo virginianus), red-tailed hawks (Buteo jamaicensis), and American alligators (Alligator mississippiensis). Avian species had high circulating β-hydroxybutyrate (10-21 mg/dl) compared to alligators (2.81 ± 0.16 mg/dl). In mammals high concentrations of this byproduct of fatty acid utilization are correlated with insulin resistance. Fasting glucose and insulin concentrations were positively correlated in eagles whereas no relationship was found between these variables for owls, hawks or alligators. Additionally, β-hydroxybutyrate concentrations were low in alligators. Similar to carnivorous mammals, ingestion of a high protein diet may have favored the utilization of fatty acids and protein for energy thereby promoting the development of insulin

  10. American alligator digestion rate of blue crabs and its implications for stomach contents analysis

    USGS Publications Warehouse

    Nifong, James C.; Rosenblatt, Adam E.; Johnson, Nathan A.; Barichivich, William; Silliman, Brian; Heithaus, Michael R.

    2012-01-01

    Stomach contents analysis (SCA) provides a snap-shot observation of a consumer's diet. Interpretation of SCA data can be complicated by many factors, including variation in gastric residence times and digestion rates among prey taxa. Although some SCA methods are reported to efficiently remove all stomach contents, the effectiveness of these techniques has rarely been tested for large irregular shaped prey with hard exoskeletons. We used a controlled feeding trial to estimate gastric residency time and decomposition rate of a large crustacean prey item, the Blue Crab (Callinectes sapidus), which is consumed by American Alligators (Alligator mississippiensis), an abundant apex predator in coastal habitats of the southeastern United States. The decomposition rate of C. sapidus in the stomachs of A. mississippiensis followed a predictable pattern, and some crab pieces remained in stomachs for at least 14 days. We also found that certain portions of C. sapidus were prone to becoming caught within the stomach or esophagus, meaning not all crab parts are consistently recovered using gastric lavage techniques. However, because the state of decomposition of crabs was predictable, it is possible to estimate time since consumption for crabs recovered from wild alligators. This information, coupled with a detailed understanding of crab distributions and alligator movement tactics could help elucidate patterns of cross-ecosystem foraging by the American Alligator in coastal habitats

  11. Relationship between body condition of American alligators and water depth in the Everglades, Florida

    USGS Publications Warehouse

    Fujisaki, Ikuko; Rice, Kenneth G.; Pearlstine, Leonard G.; Mazzotti, Frank J.

    2009-01-01

    Feeding opportunities of American alligators (Alligator mississippiensis) in freshwater wetlands in south Florida are closely linked to hydrologic conditions. In the Everglades, seasonally and annually fluctuating surface water levels affect populations of aquatic organisms that alligators consume. Since prey becomes more concentrated when water depth decreases, we hypothesized an inverse relationship between body condition and water depth in the Everglades. On average, condition of adult alligators in the dry season was significantly higher than in the wet season, but this was not the case for juveniles/subadults. The correlation between body condition and measured water depth at capture locations was weak; however, there was a significant negative correlation between the condition and predicted water depth prior to capture for all animals except for spring juveniles/subadults which had a weak positive condition-water depth relationship. Overall, a relatively strong inverse correlation occurred at 10-49 days prior to the capture day, suggesting that current body condition of alligators may depend on feeding opportunities during that period. Fitted regression of body condition on water depth (mean depth of 10 days when condition-water depth correlation was greatest) resulted in a significantly negative slope, except for spring adult females and spring juveniles/subadults for which slopes were not significantly different from zero. Our results imply that water management practices may be critical for alligators in the Everglades since water depth can affect animal condition in a relatively short period of time.

  12. Occurrence of decabromodiphenyl ethane in captive Chinese alligators (Alligator sinensis) from China.

    PubMed

    Hong, Bing; Wu, Ting; Zhao, Guangchao; Sun, Yuxin; Wang, Xinming; Zhao, Juan; Yi, Zhigang; Wu, Xiaobing; Mai, Bixian

    2015-01-01

    Decabromodiphenyl ethane (DBDPE), a replacement for decabromodiphenyl ether (deca-BDE), was investigated in captive Chinese alligators from China. DBDPE was detected in adult tissues, neonates and eggs of Chinese alligators with concentrations ranging from 4.74-192, 0.24-1.94, and 0.01-0.51 ng g(-1) lipid weight, respectively. Compared to PBDEs and PCBs, DBDPE contamination was limited in Chinese alligators. Additionally, DBDPE concentrations in adult muscles were one to three orders of magnitude higher than those in neonates and eggs, suggesting the limited maternal transfer potential of DBDPE in Chinese alligators. This is the first study to report the occurrence of DBDPE in Chinese alligators. PMID:25159734

  13. Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators.

    PubMed

    Strickland, Bradley A; Vilella, Francisco J; Belant, Jerrold L

    2016-01-01

    Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance

  14. 75 FR 34365 - Safety Zone, Alligator River, NC

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-17

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone, Alligator River, NC AGENCY: Coast Guard... the waters of the Alligator River at East Lake, North Carolina. The safety zone is intended to... on the Alligator River makes safety zone regulations necessary to provide for the safety...

  15. Coplanar PCB distribution between chorioallantoic membranes and eggs of alligators and Loggerhead sea turtles

    SciTech Connect

    Bargar, T.A.; Cobb, G.P.

    1995-12-31

    The relative distribution of coplanar polychlorinated biphenyls (PCBs) between chorioallantoic membranes (CAMS) and eggs was investigated in inviable American alligator (Alligator mississippiensis) and Loggerhead sea turtle (Caretta caretra) eggs. Cam and egg extracts were fractionated by HPLC using a porous graphitic column (PGC) and an in line switching valve to separate coplanar from non-coplanar PCBs. The fractions were collected, concentrated by nitrogen evaporation, and injected on GC-ECD (60M DB-5 capillary column) for quantification. Alligator and Loggerhead sea turtle eggs contain toxicologically significant coplanar PCBs. Mono-ortho substituted PCBs were present with greater frequency relative to non-ortho substituted PCBs in both eggs and CAMS. The presence of coplanar PCBs in eggs appears to be correlated to coplanar PCB presence in CAMS. The chorioallantoic membrane could serve as a biomarker of embryo exposure to coplanar PCBs.

  16. An algae-covered alligator rests warily

    NASA Technical Reports Server (NTRS)

    2000-01-01

    An algae-covered alligator keeps a wary eye open as it rests in one of the ponds at Kennedy Space Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  17. A mother alligator protects her young

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In the water near Kennedy Space Center, a mother alligator gathers her six offspring. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  18. International Alligator Rivers Analog Project

    SciTech Connect

    Bichard, G.F.

    1988-01-01

    The Australian Nuclear Science and Technology Organization (ANSTO), the Japan Atomic Energy Research Institute, the Swedish Nuclear Power Inspectorate, the U.K. Department of the Environment, the US Nuclear Regulatory Commission (NRC), and the Power Reactor and Nuclear Fuel Development Corporation of Japan are participating under the aegis of the Nuclear Energy Agency in the International Alligator Rivers Analog Project. The project has a duration of 3 yr, starting in 1988. The project has grown out of a research program on uranium ore bodies as analogs of high-level waste (HLW) repositories undertaken by ANSTO supported by the NRC. A primary objective of the project is to develop an approach to radionuclide transport model validation that may be used by the participants to support assessments of the safety of radioactive waste repositories. The approach involves integrating mathematical and physical modeling with hydrological and geochemical field and laboratory investigations of the analog site. The Koongarra uranium ore body has been chosen as the analog site because it has a secondary ore body that has formed over the past million years as a result of leaching by groundwater flowing through fractures in the primary ore body.

  19. Effects of egg and hatchling harvest on American alligators in Florida

    USGS Publications Warehouse

    Rice, K.G.; Percival, H.F.; Woodward, A.R.; Jennings, Michael L.

    1999-01-01

    Harvest of crocodilian eggs and young for captive rearing (ranching) has been used worldwide as an option for producing crocodilian skins and meat from wild stock. The long-term effects of harvesting a certain proportion of early age class, wild American alligators (Alligator mississippiensis) without repatriation is unknown. We removed an estimated 50% of annual production of alligators on Lakes Griffin and Jesup in central Florida over an 11-year period and monitored population levels via night-light counts. Densities of the total alligator population increased (P 0.117), and subadult (122-182 cm TL) alligators increased (P < 0.011) on harvest areas. The density of juveniles on the control area increased (P = 0.006), and the density of subadults showed some evidence of increasing (P = 0.088). No changes were detected in size distributions on the treatment areas. Nest production, as observed from aerial helicopter surveys, increased (P < 0.039) on Lake Woodruff NWR and Lake Jesup and showed some evidence of an increase on Lake Griffin (P = 0.098) during 1983-91. A 50% harvest rate of eggs or hatchlings did not adversely affect recruitment into the subadult or adult size classes.

  20. The influence of regional hydrology on nesting behavior and nest fate of the American alligator

    USGS Publications Warehouse

    Ugarte, Cristina A.; Bass, Oron L.; Nuttle, William; Mazzotti, Frank J.; Rice, Kenneth G.; Fujisaki, Ikuko; Whelan, Kevin R.T.

    2013-01-01

    Hydrologic conditions are critical to the nesting behavior and reproductive success of crocodilians. In South Florida, USA, growing human settlement has led to extensive surface water management and modification of historical water flows in the wetlands, which have affected regional nesting of the American alligator (Alligator mississippiensis). Although both natural and anthropogenic factors are considered to determine hydrologic conditions, the aspects of hydrological patterns that affect alligator nest effort, flooding (partial and complete), and failure (no hatchling) are unclear. We deconstructed annual hydrological patterns using harmonic models that estimated hydrological matrices including mean, amplitude, timing of peak, and periodicity of surface water depth and discharge and examined their effects on alligator nesting using survey data from Shark Slough, Everglades National Park, from 1985 to 2005. Nest effort increased in years with higher mean and lesser periodicity of water depth. A greater proportion of nests were flooded and failed when peak discharge occurred earlier in the year. Also, nest flooding rates were greater in years with greater periodicity of water depth, and nest failure rate was greater when mean discharge was higher. This study guides future water management decisions to mitigate negative impacts on reproduction of alligators and provides wildlife managers with a tool for assessing and modifying annual water management plans to conserve crocodilians and other wetland species.

  1. Body temperatures and behavior of American alligators during cold winter weather

    SciTech Connect

    Brisbin, I.L., Jr.; Standora, E.A.; Vargo, M.J.

    1982-04-01

    Data from two large (188 and 135 kg) male alligators (Alligator mississippiensis) indicated that 4-5 C seemed to be the lowest body temperatures that they could endure with subsequent recovery. Although one animal in shallow water managed to keep a breathing hole open for several days, in ice that was 1.5 cm thick, it later died following a decrease of its body temperature to 4.0 C. The second alligator which was located in a deeper portion of the reservoir used both terrestrial and aquatic basking behavior to raise its body temperature and level of activity. Except in the case of basking events, there was not clear evidence of significant evaluations of the body temperatures of either the live or dead alligators above those of their adjacent water. When located side-by-side, diurnal cycles of deep body temperatures exceeding adjacent water temperatures to a maximum extent near dawn and usually falling below water temperatures during the afternoon and early evening hours. The physical properties and thermal inertia of the bodies of such large alligators, when placed in appropriate microclimates, may be sufficient in themselves to explain the general patterns and levels of body temperature changes observed at these low temperatures.

  2. The isolation of parvalbumin isoforms from the tail muscle of the American alligator (Alligator mississipiensis).

    PubMed

    Laney, E L; Shabanowitz, J; King, G; Hunt, D F; Nelson, D J

    1997-04-01

    Multiple parvalbumin isoforms have been detected in the tail (skeletal) muscle of the American alligator (Alligator mississipiensis). One of these isoforms (APV-1) has been highly purified and partially characterized. Protein purification involved mainly gel filtration and anion exchange chromatography, and characterization included gel electrophoresis, amino acid composition analysis, metal ion analysis, MALDI-TOF and ESI mass spectrometry, ultraviolet and fluorescence spectroscopy, and one- and two-dimensional 500 MHz proton NMR spectroscopy. The alligator isoforms are rich in phenylalanine and deficient in the other aromatic residues as is typical for parvalbumins. In fact, the one highly purified isoform that forms the basis of this study has only phenyl-alanine as an aromatic residue. Ion exchange chromatography further indicates that this isoform has a relatively high isoelectric point (pl approximately 5.0), indicating that it is an alpha-lineage parvalbumin. This alligator parvalbumin isoform is unusual in that it has an atypically high Ca2+ content (almost 3.0 mole of Ca2+ per mole of protein) following purification, a fact supported by terbium fluorescence titration experiments. Preliminary comparative analysis of the highly purified alligator parvalbumin isoform (in the Ca2-loaded state) by two-dimensional 1H-NMR (2D 1H TOCSY and 2D 1H NOESY) indicates that there is considerable similarity in structure between the alligator protein and a homologous protein obtained from the silver hake (a saltwater fish species). PMID:9076974

  3. Bio-gas production from alligator weeds

    NASA Technical Reports Server (NTRS)

    Latif, A.

    1976-01-01

    Laboratory experiments were conducted to study the effect of temperature, sample preparation, reducing agents, light intensity and pH of the media, on bio-gas and methane production from the microbial anaerobic decomposition of alligator weeds (Alternanthera philoxeroides. Efforts were also made for the isolation and characterization of the methanogenic bacteria.

  4. Alternathera philoxeroides (Martius) Grisebach - alligator weed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biological control of Alternanthera philoxeroides, alligator weed, began when George Vogt, USDA, conducted several surveys by public transport in South America during the 1960s. Three agents were released in USA and two of them, the flea beetle Agasicles hygrophila and the moth Arcola malloi were re...

  5. Crocodiles and Alligators. Young Discovery Library Series.

    ERIC Educational Resources Information Center

    Farre, Marie

    This book is written for children ages 5 through 10. Part of a series designed to develop their curiosity, fascinate them and educate them, this volume describes the physical characteristics, behavior, and peculiar habits of crocodiles, including how to distinguish them from close relatives such as alligators, cayman, and gharials. (YP)

  6. Possible generational effects of habitat degradation on alligator reproduction

    USGS Publications Warehouse

    Fujisaki, Ikuko; Rice, K.G.; Woodward, A.R.; Percival, H.F.

    2007-01-01

    Population decline of the American alligator (Alligator mississippiensis) was observed in Lake Apopka in central Florida, USA, in the early 1980s. This decline was thought to result from adult mortality and nest failure caused by anthropogenic increases in sediment loads, nutrients, and contaminants. Reproductive impairment also was reported. Extensive restoration of marshes associated with Lake Apopka has been conducted, as well as some limited restoration measures on the lake. Monitoring by the Florida Fish and Wildlife Conservation Commission (FFWCC) has indicated that the adult alligator population began increasing in the early 1990s. We expected that the previously reported high proportion of complete nest failure (??0) during the 1980s may have decreased. We collected clutches from alligator nests in Lake Apopka from 1983 to 2003 and from 5 reference areas from 1988 to 1991, and we artificially incubated them. We used a Bayesian framework with Gibbs sampler of Markov chain Monte Carlo simulation to analyze ??0. Estimated ??0was consistently higher in Lake Apopka compared with reference areas, and the difference in ??0 ranged from 0.19 to 0.56. We conducted change point analysis to identify and test the significance of the change point in ??0in Lake Apopka between 1983 and 2003, indicating the point of reproductive recovery. The estimated Bayes factor strongly supported the single change point hypothesis against the no change point hypothesis. The major downward shift in ??0 probably occurred in the mid-1990s, approximately a generation after the major population decline in the 1980s. Furthermore, estimated ??0 values after the change point (0.21) were comparable with those of reference areas (0.07-0.31). These results combined with the monitoring by FFWCC seem to suggest that anthropogenic habitat degradation caused reproductive impairment of adult females and decreases in ??0 occurred with the sexual maturity of a new generation of breeding females. Long

  7. A mother alligator protects her young

    NASA Technical Reports Server (NTRS)

    2000-01-01

    American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  8. TRPV4 associates environmental temperature and sex determination in the American alligator

    PubMed Central

    Yatsu, Ryohei; Miyagawa, Shinichi; Kohno, Satomi; Saito, Shigeru; Lowers, Russell H.; Ogino, Yukiko; Fukuta, Naomi; Katsu, Yoshinao; Ohta, Yasuhiko; Tominaga, Makoto; Guillette Jr, Louis J.; Iguchi, Taisen

    2015-01-01

    Temperature-dependent sex determination (TSD), commonly found among reptiles, is a sex determination mode in which the incubation temperature during a critical temperature sensitive period (TSP) determines sexual fate of the individual rather than the individual’s genotypic background. In the American alligator (Alligator mississippiensis), eggs incubated during the TSP at 33 °C (male producing temperature: MPT) yields male offspring, whereas incubation temperatures below 30 °C (female producing temperature: FPT) lead to female offspring. However, many of the details of the underlying molecular mechanism remains elusive, and the molecular link between environmental temperature and sex determination pathway is yet to be elucidated. Here we show the alligator TRPV4 ortholog (AmTRPV4) to be activated at temperatures proximate to the TSD-related temperature in alligators, and using pharmacological exposure, we show that AmTRPV4 channel activity affects gene expression patterns associated with male differentiation. This is the first experimental demonstration of a link between a well-described thermo-sensory mechanism, TRPV4 channel, and its potential role in regulation of TSD in vertebrates, shedding unique new light on the elusive TSD molecular mechanism. PMID:26677944

  9. TRPV4 associates environmental temperature and sex determination in the American alligator.

    PubMed

    Yatsu, Ryohei; Miyagawa, Shinichi; Kohno, Satomi; Saito, Shigeru; Lowers, Russell H; Ogino, Yukiko; Fukuta, Naomi; Katsu, Yoshinao; Ohta, Yasuhiko; Tominaga, Makoto; Guillette, Louis J; Iguchi, Taisen

    2015-01-01

    Temperature-dependent sex determination (TSD), commonly found among reptiles, is a sex determination mode in which the incubation temperature during a critical temperature sensitive period (TSP) determines sexual fate of the individual rather than the individual's genotypic background. In the American alligator (Alligator mississippiensis), eggs incubated during the TSP at 33 °C (male producing temperature: MPT) yields male offspring, whereas incubation temperatures below 30 °C (female producing temperature: FPT) lead to female offspring. However, many of the details of the underlying molecular mechanism remains elusive, and the molecular link between environmental temperature and sex determination pathway is yet to be elucidated. Here we show the alligator TRPV4 ortholog (AmTRPV4) to be activated at temperatures proximate to the TSD-related temperature in alligators, and using pharmacological exposure, we show that AmTRPV4 channel activity affects gene expression patterns associated with male differentiation. This is the first experimental demonstration of a link between a well-described thermo-sensory mechanism, TRPV4 channel, and its potential role in regulation of TSD in vertebrates, shedding unique new light on the elusive TSD molecular mechanism. PMID:26677944

  10. HISTOPATHOLOGY OF GASTRIC WALL IN CHINESE ALLIGATOR ALLIGATOR SINENSIS INFECTED WITH ORTLEPPASCARIS SINENSIS (NEMATODA: ASCARIDOIDEA).

    PubMed

    Zhao, Jinhong; Wang, Shaosheng; Tu, Genjun; Zhou, Yongkang; Wu, Xiaobing; Li, Chaopin

    2015-01-01

    Crocodiles are susceptible to infection with a wide array of external and internal gastrointestinal helminths, yet little is known on the histopathology following infection or the effects of these parasites. The present study was aimed at evaluating the impact of infection by Ortleppascaris sinensis (Nematoda: Ascaridoidea) on the stomach of captive Alligator sinensis. The histological examination of the stomach revealed presence of superficial ulcer in mucous layer and granulomatous inflammation in submucous layer at entire gastric walls of the Alligator sinensis. Our findings also confirm that development of Ortleppascaris sinensis is in close association with the wall of the stomach. PMID:26319836

  11. Contaminants in American alligator eggs from Lake Apopka, Lake Griffin, and Lake Okeechobee, Florida

    USGS Publications Warehouse

    Heinz, G.H.; Percival, H.F.; Jennings, Michael L.

    1991-01-01

    Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), and 16 elements were measured in American alligator (Alligator mississippiensis) eggs collected in 1984 from Lakes Apopka, Griffin, and Okeechobee in central and south Florida. Organochlorine pesticides were highest in eggs from Lake Apopka. None of the elements appeared to be present at harmful concentrations in eggs from any of the lakes. A larger sample of eggs was collected in 1985, but only from Lakes Griffin, a lake where eggs were relatively clean, and Apopka, where eggs were most contaminated. In 1985, hatching success of artificially incubated eggs was lower for Lake Apopka, and several organochlorine pesticides were higher than in eggs from Lake Griffin. However, within Lake Apopka, higher levels of pesticides in chemically analyzed eggs were not associated with reduced hatching success of the remaining eggs in the clutch. Therefore, it did not appear that any of the pesticides we measured were responsible for the reduced hatching of Lake Apopka eggs.

  12. Molecular and functional characterization of BAFF from the Yangtze alligator (Alligator sinensis, Alligatoridae).

    PubMed

    Zhang, Jia-Xin; Song, Ren; Sang, Ming; Sun, Si-Qing; Ma, Lei; Zhang, Jie; Zhang, Shuang-Quan

    2015-10-01

    B-cell activating factor (BAFF) from the TNF family is critical for B-cell survival and maturation. In this study, we identified a Yangtze alligator (Alligator sinensis, Alligatoridae) BAFF cDNA, designated as asBAFF, using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The open reading frame of this cDNA encodes a 287-amino acid protein containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian and avian BAFF. The amino acid identity between biologically soluble asBAFF (assBAFF) and csBAFF, hsBAFF, and msBAFF is 94, 76, and 71%, respectively. Real-time quantitative PCR analysis showed that the asBAFF gene is strongly expressed in the spleen. Since BAFF is always expressed as inclusion bodies in bacteria, it is difficult to purify. To enhance the soluble expression of assBAFF in Escherichia coli, we fused the extracellular region of the asBAFF gene to a small ubiquitin-related modifier gene (SUMO). Purified assBAFF was able to promote the survival of splenic lymphocytes and co-stimulate the proliferation of mouse B cells with anti-mouse IgM. These findings suggest that asBAFF plays an important role in the survival and proliferation of Yangtze alligator B cells, and because it is evolutionarily highly conserved, functional cross-reactivity exists between mammalian and Yangtze alligator BAFF. PMID:26116474

  13. The first fossil skull of Alligator sinensis from the Pleistocene, Taiwan, with a paleogeographic implication of the species

    NASA Astrophysics Data System (ADS)

    Hsi-yin, Shan; Yen-nien, Cheng; Xiao-chun, Wu

    2013-06-01

    A nearly complete fossil skull of Alligatoridae from the Pleistocene, Penghu Channel, east of Taiwan, is reported. It can be referred to the most latest clade of Alligatorinae, which includes Alligator sinensis, Alligator mississippiensis and Alligator mefferdi, on the basis of the following features: the splenial is excluded from the mandibular symphysis; the anterior tip of the splenial passes dorsal to the Meckelian groove; and the mandible is gently curved between the fourth alveoli and the mid dentary. It differs from A. mississippiensis and A. mefferdi mainly in the following characters: the breadth between the supratemporal fenestrae is approximately equal to the interorbital width, the snout is about half the length of the skull; and the anterior part of the snout is subtriangular in dorsal view. These features suggest that the Penghu alligator is most probably referable to A. sinensis. This is the only fossil skull of A. sinensis known. The discovery of the skull in Penghu Channel not only provides the first solid fossil evidence to indicate that the geological distribution of A. sinensis extended farther southeast than the historical/archeological range of the species but also adds new information on the biodiversity of the Penghu fauna.

  14. The Good, the Bad, and the Unknown: Microbial Symbioses of the American Alligator.

    PubMed

    Keenan, Sarah W; Elsey, Ruth M

    2015-12-01

    Vertebrates coexist with microorganisms in diverse symbiotic associations that range from beneficial to detrimental to the host. Most research has aimed at deciphering the nature of the composite microbial assemblage's genome, or microbiome, from the gastrointestinal (GI) tract and skin of mammals (i.e., humans). In mammals, the GI tract's microbiome aids digestion, enhances uptake of nutrients, and prevents the establishment of pathogenic microorganisms. However, because the GI tract microbiome of the American alligator (Alligator mississippiensis) is distinct from that of all other vertebrates studied to date, being comprised of Fusobacteria in the lower GI tract with lesser abundances of Firmicutes, Proteobacteria, and Bacteroidetes, the function of these assemblages is largely unknown. This review provides a synthesis of our current understanding of the composition of alligators' microbiomes, highlights the potential role of microbiome members in alligators' health (the good), and presents a brief summary of microorganisms detrimental to alligators' health (the bad) including Salmonella spp. and others. Microbial assemblages of the GI tract have co-evolved with their vertebrate host over geologic time, which means that evolutionary hypotheses can be tested using information about the microbiome. For reptiles and amphibians, the number of taxa studied at present is limited, thereby restricting evolutionary insights. Nevertheless, we present a compilation of our current understanding of reptiles' and amphibians' microbiomes, and highlight future avenues of research (the unknown). As in humans, composition of microbiome assemblages provides a promising tool for assessing hosts' health or disease. By further exploring present-day associations between symbiotic microorganisms in the microbiomes of reptiles and amphibians, we can better identify good (beneficial) and bad (detrimental) microorganisms, and unravel the evolutionary history of the acquisition of

  15. Habitat Suitability Index Models: American Alligator

    USGS Publications Warehouse

    Newsom, John D.; Joanen, Ted; Howard, Rebecca J.

    1987-01-01

    A review and synthesis of existing information were used to develop a model for evaluating American alligator habitat quality. The model is applicable in marshes along the northern Gulf of Mexico. It is scaled to produce an index between 0 (unsuitable habitat) and 1.0 (optimal habitat). Habitat suitability index models are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for model application and techniques for measuring model variables are described.

  16. WILDLIFE - ALLIGATOR BEGINS TO CROSS KENNEDY PARKWAY

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Harold O'Connor, manager of the Merritt Island Wildlife Refuge, watches a 10-foot-long alligator inch its way toward a busy highway at the Kennedy Space Center. O'Connor, aided by assistant Jerome Carroll, not shown, guided the large gator to safety in a nearby pond, several miles south of the Vehicle Assembly Building, in background. The Apollo 12 astronauts will be launched no earlier than November 14, 1969, from the Kennedy Space Center on the Nation's second manned lunar landing mission.

  17. American Alligator Research on the Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Lowers, Russell H.

    2010-01-01

    This slide presentation reviews the research conducted at the Kennedy Space Center on the American Alligator. The objectives of the research were to establish life history baseline at the Kennedy Space Center and at the Merit Island National Wildlife Reserve (MINWR). Some of the factors that were examined are: nesting success, movement patterns, and population structure. Another objective was to determine the overall health of the alligator population, by analyzing blood and tissue chemistry, and urine analysis. A third objective was to compare alligators at KSC/MINWR to the statewide population. Some of the results are shown in charts and graphs.

  18. Reproductive toxins and alligator abnormalities at Lake Apopka, Florida.

    PubMed Central

    Semenza, J C; Tolbert, P E; Rubin, C H; Guillette, L J; Jackson, R J

    1997-01-01

    The alligator population at Lake Apopka in central Florida declined dramatically between 1980 and 1987. Endocrine-disrupting chemicals and specifically DDT metabolites have been implicated in the alligators' reproductive failure. The DDT metabolite hypothesis is based largely on the observation of elevated concentrations of p,p-DDE and p,p-DDD in alligator eggs obtained from Lake Apopka in 1984 and 1985. In the following commentary, we draw attention to two nematocides that are established reproductive toxins in humans, dibromochloropropane (DBCP) and ethylene dibromide (EDB), which could also have played a role in the reproductive failure observed in alligators from Lake Apopka in the early 1980s. Images Figure 1. PMID:9349835

  19. An alligator basks in the sun at KSC.

    NASA Technical Reports Server (NTRS)

    2000-01-01

    On the bank of a levee near Schwartz Rd. at Kennedy Space Center, an alligator suns itself with a wary eye out for trespassers. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the Merritt Island National Wildlife Refuge, which shares a boundary with the Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  20. ENDOCRINE DISRUPTING CONTAMINANTS AND ALLIGATOR EMBRYOS: A LESSON FROM WILDLIFE?

    EPA Science Inventory

    Many xenobiotic compounds introduced into the environment by human activity adversely affect wildlife. A number of these contaminants have been hypothesized to induce non lethal, multigenerational effects by acting as endocrine disrupting agents. One case is that of the alligator...

  1. 109. Doughton Park Recreation Area. View of alligator back and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    109. Doughton Park Recreation Area. View of alligator back and the parkway seen from bluff mountain. Looking west. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  2. Incubation history prior to the canonical thermosensitive period determines sex in the American alligator.

    PubMed

    McCoy, Jessica A; Parrott, Benjamin B; Rainwater, Thomas R; Wilkinson, Phillip M; Guillette, Louis J

    2015-10-01

    Despite the widespread occurrence of environmental sex determination (ESD) among vertebrates, our knowledge of the temporal dynamics by which environmental factors act on this process remains limited. In many reptiles, incubation temperature determines sex during a discrete developmental window just prior to and coincident with the differentiation of the gonads. Yet, there is substantial variation in sex ratios among different clutches of eggs incubated at identical temperatures during this period. Here, we test the hypothesis that temperatures experienced prior to the reported thermosensitive period for alligators (Alligator mississippiensis) can impact how the sex determination system responds to thermal cues later in development. Temperature shift experiments on eggs collected from the field within 24  h of oviposition were employed to decouple various maternal influences from thermal effects, and results demonstrate a previously undefined window of thermosensitivity occurring by stage 15 of embryonic development, six stages earlier than previously reported. We also examine the intrasexual expression of several male- and female-biased genes and show that while male-biased genes display no intrasexual differences, ovarian CYP19A1 (aromatase) transcript abundance differs by approximately twofold depending on thermal exposures experienced at early stages of embryonic development. These findings expand our understanding of the ESD in the alligator and provide the rationale for reevaluation of the temporal dynamics of sex determination in other crocodilians. PMID:26183894

  3. Population status of the American alligator on the Savannah River Plant, South Carolina

    SciTech Connect

    Murphy, T.M.

    1981-04-01

    Estimates are presented of alligator numbers, size distribution, sex ratios, reproductive effort, and population trends for all major components of the entire Savannah River Plant (SRP) alligator population. Savannah River Plant operations have impacted the alligator population in many different ways. The formation of man-made reservoirs has dramatically increased the amount of aquatic habitat available to alligators and has therefore increased the carrying capacity of the SRP site for this species. The thermal alteration of aquatic habitats on the SRP has also impacted the resident alligator population. Temperature elevations of aquatic habitat to greater than 38/sup 0/C result in the loss of this habitat to alligators. Moderate thermal increases on the other hand are responded to by alligator movement. The current information available on the alligators of the SRP suggests the following future trends: low density populations distant from thermally altered areas will continue at a low density with the exception of localized increases.

  4. Nutrient and organochlorine pesticide concentrations in American alligator eggs and their associations with clutch viability.

    PubMed

    Rauschenberger, R Heath; Sepúlveda, Maria S; Wiebe, Jon J; Wiebe, Janet E; Honeyfield, Dale C; Gross, Timothy S

    2009-12-01

    Since the early 1900s, the lakes of the Ocklawaha basin in central Florida have experienced ecological degradation due to anthropogenic development. One species affected by this degradation is the American alligator Alligator mississippiensis, which has suffered from poor clutch viability and embryo mortality. Although some studies indicate that organochlorine pesticides (OCPs) may be involved, OCPs do not account for all of the variation seen in hatch rates. Indeed, nutrition and non-OCP contaminants have been associated with developmental problems in fish and birds. Our study evaluated embryo mortality in alligators at reference and OCP-contaminated sites as a function of exposure to OCPs, polychlorinated biphenyls (PCBs), and polyaromatic hydrocarbons (PAHs), along with egg nutrients (Zn, Se, and vitamins A, E, and B1). The four-pronged study consisted of a case-control cohort study, an expanded field study, a topical egg treatment thiamine amelioration experiment, and a topical egg treatment thiamine antagonist experiment. The results from the two field studies suggested that the total thiamine levels in the eggs were positively associated with clutch viability and negatively associated with the lipid content and certain OCPs measured in egg yolks. In addition, PCBs, PAHs, Zn, Se, and vitamins A and E were not found to be associated with the observed clutch viability defects. The thiamine levels in the eggs explained 38% of the variation in clutch survival in the case-control cohort study and 27% in the expanded field study. The topical egg treatment experiments were successful in elevating the thiamine concentrations in the albumin but not the yolk. No significant differences were noted among treatment groups in either egg treatment experiment with respect to clutch survival. In summary, thiamine egg concentrations explain some of the variation in the clutch viability of free-ranging alligators, but the cause-effect relationships are still unclear. PMID

  5. Microsatellite DNA analyses support an east-west phylogeographic split of American alligator populations.

    PubMed

    Davis, Lisa M; Glenn, Travis C; Strickland, Denise C; Guillette, Louis J; Elsey, Ruth M; Rhodes, Walter E; Dessauer, Herbert C; Sawyer, Roger H

    2002-12-15

    We examined the population genetic structure of American alligators (Alligator mississippiensis) sampled from 12 localities across the southeastern United States. The primary goal of this study was to determine the extent of population differentiation among alligators from four Florida lakes using eight microsatellite loci and compare the results to additional sites located at varying distances from them. Analyses of population structure revealed little differentiation (F(ST)=0.039; Rho=0.012) among the four Florida lakes, Apopka, Griffin, Orange and Woodruff, which are all located in the St. John&'s River watershed in north-central Florida. Further, there was little differentiation among these samples and samples collected from the Everglades National Park (F(ST)=0.044; Rho=0.009) and south Georgia (F(ST)=0.045; Rho=0.032). Therefore, these six samples were pooled together as a "FL/sGA group." Similarly, samples collected in the western extent of the range, Anahuac National Wildlife Refuge in Texas and Salvador Wildlife Management Area, Marsh Island Wildlife Refuge and Rockefeller Wildlife Refuge in Louisiana, also lacked population structure (F(ST)=0.024; R(ST)=0.040). These four populations were pooled into the "TX/LA group." Comparisons of these two groups with samples taken from the Santee Coastal Reserve in South Carolina and Mobile, Alabama yielded three to four times more differentiation among groups (F(ST)=0.131; Rho=0.187). These and other analyses support the hypothesis of an east-west phylogeographic split in American alligator populations and are consistent with studies of many freshwater fish and aquatic and terrestrial turtles distributed throughout this same geographic region. PMID:12461815

  6. Unidirectional airflow in the lungs of alligators.

    PubMed

    Farmer, C G; Sanders, Kent

    2010-01-15

    The lungs of birds move air in only one direction during both inspiration and expiration through most of the tubular gas-exchanging bronchi (parabronchi), whereas in the lungs of mammals and presumably other vertebrates, air moves tidally into and out of terminal gas-exchange structures, which are cul-de-sacs. Unidirectional flow purportedly depends on bellowslike ventilation by air sacs and may have evolved to meet the high aerobic demands of sustained flight. Here, we show that air flows unidirectionally through parabronchi in the lungs of the American alligator, an amphibious ectotherm without air sacs, which suggests that this pattern dates back to the basal archosaurs of the Triassic and may have been present in their nondinosaur descendants (phytosaurs, aetosaurs, rauisuchians, crocodylomorphs, and pterosaurs) as well as in dinosaurs. PMID:20075253

  7. 33 CFR 165.T05-0091 - Safety Zone; Alligator River, NC.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; Alligator River, NC... Safety Zone; Alligator River, NC. (a) Definitions. For the purposes of this section, Captain of the Port... on the waters of the Alligator River centered at (35°54′3″ N/076°00′25″ W) a position directly...

  8. Slow isotope turnover rates and low discrimination values in the American alligator: implications for interpretation of ectotherm stable isotope data.

    PubMed

    Rosenblatt, Adam E; Heithaus, Michael R

    2013-01-01

    Stable isotope analysis has become a standard ecological tool for elucidating feeding relationships of organisms and determining food web structure and connectivity. There remain important questions concerning rates at which stable isotope values are incorporated into tissues (turnover rates) and the change in isotope value between a tissue and a food source (discrimination values). These gaps in our understanding necessitate experimental studies to adequately interpret field data. Tissue turnover rates and discrimination values vary among species and have been investigated in a broad array of taxa. However, little attention has been paid to ectothermic top predators in this regard. We quantified the turnover rates and discrimination values for three tissues (scutes, red blood cells, and plasma) in American alligators (Alligator mississippiensis). Plasma turned over faster than scutes or red blood cells, but turnover rates of all three tissues were very slow in comparison to those in endothermic species. Alligator δ(15)N discrimination values were surprisingly low in comparison to those of other top predators and varied between experimental and control alligators. The variability of δ(15)N discrimination values highlights the difficulties in using δ(15)N to assign absolute and possibly even relative trophic levels in field studies. Our results suggest that interpreting stable isotope data based on parameter estimates from other species can be problematic and that large ectothermic tetrapod tissues may be characterized by unique stable isotope dynamics relative to species occupying lower trophic levels and endothermic tetrapods. PMID:23303328

  9. Alligator physiology and life history: the importance of temperature.

    PubMed

    Lance, Valentine A

    2003-07-01

    Alligators are the most northerly distributed of the extant Crocodilia. Reproducing populations are found as far north as 35 degrees latitude in the freshwater marshes and rivers of coastal North Carolina, and as far south as 25 degrees latitude in the Florida Keys. Thus different populations are exposed to very different annual thermal cycles. Alligators stop eating when ambient temperature drops below 16 degrees C. This anorexia lasts at least 6 months at 35 degrees latitude. In southwest Louisiana alligators stop feeding in October and do not resume feeding until late March or early April. It is only during the warmer months when actively feeding that growth occurs. Even with this restricted growing season Louisiana alligators grow about 30 cm a year for the first 6 years. When alligators reach sexual maturity at about 1.85 m total length growth slows in both sexes, but is significantly slower in females than males. As a result of differences in thermal regime sexual maturity is estimated at around 18 years in North Carolina and about 10 years in Louisiana. Females lay one clutch of around 40 eggs in June, but the time of nesting is also tightly linked to temperature. In a cool spring nesting can occur as late as July 5th, and in a warm spring as early as June 5th. Immature male alligators undergo a seasonal hormonal cycle similar to fully mature breeding males, but testosterone levels differ by an order of magnitude. The number of mature females reproducing each year is rarely greater than 50%, but data on internest interval is lacking. Immature female alligators show no seasonal hormonal cycle. PMID:12855291

  10. The alligator gut microbiome and implications for archosaur symbioses

    PubMed Central

    Keenan, Sarah W.; Engel, Annette Summers; Elsey, Ruth M.

    2013-01-01

    Among vertebrate gastrointestinal microbiome studies, complete representation of taxa is limited, particularly among reptiles. Here, we provide evidence for previously unrecognized host-microbiome associations along the gastrointestinal tract from the American alligator, a crown archosaur with shared ancestry to extinct taxa, including dinosaurs. Microbiome compositional variations reveal that the digestive system consists of multiple, longitudinally heterogeneous microbiomes that strongly correlate to specific gastrointestinal tract organs, regardless of rearing histories or feeding status. A core alligator gut microbiome comprised of Fusobacteria, but depleted in Bacteroidetes and Proteobacteria common to mammalians, is compositionally unique from other vertebrate gut microbiomes, including other reptiles, fish, and herbivorous and carnivorous mammals. As such, modern alligator gut microbiomes advance our understanding of archosaur gut microbiome evolution, particularly if conserved host ecology has retained archosaur-specific symbioses over geologic time. PMID:24096888

  11. An urban Northeastern United States alligator bite.

    PubMed

    Shepherd, Suzanne Moore; Shoff, William H

    2014-05-01

    Individuals who live and work in the Southeastern coastal range of the 3 US crocodilian carnivores, American alligators, American crocodiles, and caiman, understand the risks of reptile-human encounters. Individuals who live in other parts of the country maybe exposed through contact with exotic pets at private homes, small menageries, or petting zoos or from escaped or abandoned animals. During these encounters, individuals may be severely injured.Emergency medical services, law enforcement, and animal welfare workers in nonhabitat areas are usually not trained in the handling and safe removal of injured individuals from the scene when the reptile is present. The emergency management of large crocodilian injuries is similar to that of other major trauma; however, providers also must take into consideration the significant crush component potentially inflicted by the tremendous bite power and shaking inflicting during attacks by these large reptiles, appropriate antibiotic coverage for less common organisms that inhabit their mouths, and management of possible psychological distress, including posttraumatic stress disorder produced by such an unusual attack. Emergency physicians should support the development of a readily available national database of scientifically collect information on attacks to inform appropriate care and support efforts to explore responsible measures that the USDA Animal and Plant Health Inspection Service and other appropriate local, state, and federal agencies can take to ensure ethical and biologically sustainable management of our large reptiles, which also helps to ensure the safety of the public. PMID:24332253

  12. Potential molecular wires and molecular alligator clips

    NASA Astrophysics Data System (ADS)

    Schumm, Jeffry S.; Pearson, Darren L.; Jones, LeRoy, II; Hara, Ryuichiro; Tour, James M.

    1996-12-01

    The synthesis of oligo(2-ethylphenylene-ethynylene)s, oligo(2-(0957-4484/7/4/023/img1-ethylheptyl)phenylene-ethynylene)s, and oligo(3-ethylthiophene-ethynylene)s is described via an iterative divergent convergent approach. Synthesized were the monomer, dimer, tetramer, octamer and 16-mer of the oligo(3-ethylthiophene-ethynylene)s and oligo(2-0957-4484/7/4/023/img1-ethylheptyl)phenylene-ethynylene)s. The 16-mers are 100 Å and 128 Å long, respectively. At each stage in the iteration, the length of the framework doubles. Only three sets of reaction conditions are needed for the entire iterative synthetic sequence; an iodination, a protodesilylation, and a Pd/Cu-catalyzed cross coupling. The oligomers were characterized spectroscopically and by mass spectrometry. The optical properties are presented which show the stage of optical absorbance saturation. The size exclusion chromatography values for the number average weights, relative to polystyrene, illustrate the tremendous differences in the hydrodynamic volume of these rigid rod oligomers versus the random coils of polystyrene. These differences become quite apparent at the octamer stage. The preparation of thiol-protected end groups is described. These may serve as molecular alligator clips for adhesion to gold surfaces. These oligomers may act as molecular wires in molecular electronic devices and they also serve as useful models for understanding related bulk polymers.

  13. Alligator osteoderms: mechanical behavior and hierarchical structure.

    PubMed

    Chen, Irene H; Yang, Wen; Meyers, Marc A

    2014-02-01

    Osteoderms are bony scutes embedded underneath the dermal layers of the skin acting as a protection of the alligator (Archosauria: Crocodylia) internal organs and tissues. Additionally, these scutes function as an aid in temperature regulation. The scutes are inter-linked by fibrous connective tissue. They have properties similar to bone and thus have the necessary toughness to provide protection against predators. The scutes consist of hydroxyapatite and have a porosity of approximately 12%. They have a disc-like morphology with a ridge along the middle of the plate, called the keel; the outer perimeter of the disc has depressions, grooves, and jagged edges which anchor the collagen and act as sutures. Computerized tomography reveals the pattern of elongated pores, which emanate from the keel in a radial pattern. Micro-indentation measurements along the cross-section show a zigzag behavior due to the porosity. Compression results indicate that the axial direction is the strongest (UTS ~67 MPa) and toughest (11 MJ/m(3)); this is the orientation in which they undergo the largest external compression forces from predator teeth. Toughening mechanisms are identified through observation of the damage progression and interpreted in mechanistic terms. They are: flattening of pores, microcrack opening, and microcrack growth and coalescence. Collagen plays an essential role in toughening and plasticity by providing bridges that impede the opening of the cracks and prevent their growth. PMID:24411399

  14. Morphological and molecular characterization of Ortleppascaris sinensis sp. nov. (Nematoda: Ascaridoidea) from the Chinese alligator Alligator sinensis.

    PubMed

    Zhao, J H; Wang, S S; Tu, G J; Zhou, Y K; Wu, X B

    2016-05-01

    A new nematode species, Ortleppascaris sinensis sp. nov. (Ascaridoidea), is described from specimens found in the stomach and intestine of the Chinese alligator Alligator sinensis Fauvel, 1879 (Crocodilian: Alligatoridae) in the National Nature Reserve of Chinese Alligator (Chinese Crocodile Lake) in Anhui Province, China. This is the first description of O. sinensis sp. nov. in both China and this crocodile host, increasing its distribution in South Asia as well as expanding the number of helminths known to infect this crocodile. The detailed description of O. sinensis sp. nov., based on light and scanning electron microscopic examination, provides new taxonomic data for this species, and we also report sequences of the internal transcribed spacers (ITS), small subunit DNA segments (18S) and the cytochrome oxidase I (COI) gene. PMID:25882968

  15. Voltage oscillations and ionic conductances in hair cells isolated from the alligator cochlea.

    PubMed

    Fuchs, P A; Evans, M G

    1988-12-01

    Tall hair cells were isolated by enzymatic and mechanical dissociation from selected regions of the apical half of the alligator (A. mississippiensis) cochlea. Single cells were subjected to voltage-clamp and current-clamp using the tight-seal whole-cell recording technique. Most hair cells isolated from the apex of the cochlea produced slowly regenerative depolarizations or Na action potentials during current injection, whereas hair cells isolated from more basal regions usually produced voltage oscillations (ringing) in response to depolarizing current injection, an indication of electrical resonance. Resonant frequencies ranged from 50 to 157 Hz in different cells. The higher-frequency cells tended to have larger and more rapidly activating outward currents than did the lower-frequency cells. An inward Ca current and an outward Ca-activated K current were present in all hair cells. In addition, an inwardly rectifying current and a small, transient outward current were often seen. Thus, we conclude that an electrical tuning mechanism is present in alligator hair cells. The role of the ionic conductances in shaping hair cell responses to current injection, and the possible contributions of these electrical responses to cochlear function are discussed. PMID:3244125

  16. Three-dimensional skeletal kinematics of the shoulder girdle and forelimb in walking Alligator

    PubMed Central

    Baier, David B; Gatesy, Stephen M

    2013-01-01

    Crocodylians occupy a key phylogenetic position for investigations of archosaur locomotor evolution. Compared to the well-studied hindlimb, relatively little is known about the skeletal movements and mechanics of the forelimb. In this study, we employed manual markerless XROMM (X-ray Reconstruction Of Moving Morphology) to measure detailed 3-D kinematics of the shoulder girdle and forelimb bones of American alligators (Alligator mississippiensis) walking on a treadmill. Digital models of the interclavicle, scapulocoracoid, humerus, radius and ulna were created using a 3-D laser scanner. Models were articulated and aligned to simultaneously recorded frames of fluoroscopic and standard light video to reconstruct and measure joint motion. Joint coordinate systems were established for the coracosternal, glenohumeral and elbow joints. Our analysis revealed that the limb joints only account for about half of fore/aft limb excursion; the remaining excursion results from shoulder girdle movements and lateral bending of the vertebral column. Considerable motion of each scapulocoracoid relative to the vertebral column is consistent with coracosternal mobility. The hemisellar design of the glenohumeral joint permits some additional translation, or sliding in the fore-aft plane, but this movement does not have much of an effect on the distal excursion of the bone. PMID:24102540

  17. Alligators and crocodiles as indicators for restoration of Everglades ecosystems

    USGS Publications Warehouse

    Mazzotti, Frank J.; Best, G. Ronnie; Brandt, Laura A.; Cherkiss, Michael S.; Jeffery, Brian M.; Rice, Kenneth G.

    2009-01-01

    Alligators and crocodiles integrate biological impacts of hydrological operations, affecting them at all life stages through three key aspects of Everglades ecology: (1) food webs, (2) diversity and productivity, and (3) freshwater flow. Responses of crocodilians are directly related to suitability of environmental conditions and hydrologic change. Correlations between biological responses and environmental conditions contribute to an understanding of species' status and trends over time. Positive or negative trends of crocodilian populations relative to hydrologic changes permit assessment of positive or negative trends in restoration. The crocodilian indicator uses monitoring parameters (performance measures) that have been shown to be both effective and efficient in tracking trends. The alligator component uses relative density (reported as an encounter rate), body condition, and occupancy rates of alligator holes; the crocodile component uses juvenile growth and hatchling survival. We hypothesize that these parameters are correlated with hydrologic conditions including depth, duration, timing, spatial extent and water quality. Salinity is a critical parameter in estuarine habitats. Assessments of parameters defined for crocodilian performance measures support these hypotheses. Alligators and crocodiles are the charismatic megafauna of the Everglades. They are both keystone and flagship species to which the public can relate. In addition, the parameters used to track trends are easy to understand. They provide answers to the following questions: How has the number of alligators or crocodiles changed? Are the animals fatter or thinner than they should be? Are the animals in the places (in terms of habitat and geography) where they should be? As surely as there is no other Everglades, no other single species defines the Everglades as does the American alligator. The Everglades is the only place in the world where both alligators and crocodiles exist. Crocodilians

  18. Necropsy findings in American alligator late-stage embryos and hatchlings from northcentral Florida lakes contaminated with organochlorine pesticides

    USGS Publications Warehouse

    Sepulveda, M.S.; Del, Piero F.; Wiebe, J.J.; Rauschenberger, H.R.; Gross, T.S.

    2006-01-01

    Increased American alligator (Alligator mississippiensis) embryo and neonatal mortality has been reported from several northcentral Florida lakes contaminated with old-use organochlorine pesticides (OCPs). However, a clear relationship among these contaminants and egg viability has not been established, suggesting the involvement of additional factors in these mortalities. Thus, the main objective of this study was to determine the ultimate cause of mortality of American alligator late-stage embryos and hatchlings through the conduction of detailed pathological examinations, and to evaluate better the role of OCPs in these mortalities. Between 2000 and 2001, 236 dead alligators were necropsied at or near hatching (after ???65 days of artificial incubation and up to 1 mo of age posthatch). Dead animals were collected from 18 clutches ranging in viability from 0% to 95%. Total OCP concentrations in yolk ranged from ???100 to 52,000 ??g/kg, wet weight. The most common gross findings were generalized edema (34%) and organ hyperemia (29%), followed by severe emaciation (14%) and gross deformities (3%). Histopathologic examination revealed lesions in 35% of the animals, with over half of the cases being pneumonia, pulmonary edema, and atelectasis. Within and across clutches, dead embryos and hatchlings compared with their live cohorts were significantly smaller and lighter. Although alterations in growth and development were not related to yolk OCPs, there was an increase in prevalence of histologic lesions in clutches with high OCPs. Overall, these results indicate that general growth retardation and respiratory abnormalities were a major contributing factor in observed mortalities and that contaminants may increase the susceptibility of animals to developing certain pathologic conditions. ?? Wildlife Disease Association 2006.

  19. 33 CFR 334.760 - Naval Support Activity Panama City and Alligator Bayou, a tributary of St. Andrew Bay, Fla...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... City and Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. 334.760 Section... Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. (a) The area. The waters within... the south side of the entrance to Alligator Bayou; thence directly across the entrance to a point...

  20. 33 CFR 334.760 - Naval Support Activity Panama City and Alligator Bayou, a tributary of St. Andrew Bay, Fla...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... City and Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. 334.760 Section... Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. (a) The area. The waters within... the south side of the entrance to Alligator Bayou; thence directly across the entrance to a point...

  1. 50 CFR 23.70 - How can I trade internationally in American alligator and other crocodilian skins, parts, and...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... American alligator and other crocodilian skins, parts, and products? 23.70 Section 23.70 Wildlife and... in Certain Specimens § 23.70 How can I trade internationally in American alligator and other... section, crocodilian means all species of alligator, caiman, crocodile, and gavial of the order...

  2. 50 CFR 23.70 - How can I trade internationally in American alligator and other crocodilian skins, parts, and...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... American alligator and other crocodilian skins, parts, and products? 23.70 Section 23.70 Wildlife and... in Certain Specimens § 23.70 How can I trade internationally in American alligator and other... section, crocodilian means all species of alligator, caiman, crocodile, and gavial of the order...

  3. 50 CFR 23.70 - How can I trade internationally in American alligator and other crocodilian skins, parts, and...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... American alligator and other crocodilian skins, parts, and products? 23.70 Section 23.70 Wildlife and... in Certain Specimens § 23.70 How can I trade internationally in American alligator and other... section, crocodilian means all species of alligator, caiman, crocodile, and gavial of the order...

  4. 50 CFR 23.70 - How can I trade internationally in American alligator and other crocodilian skins, parts, and...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... American alligator and other crocodilian skins, parts, and products? 23.70 Section 23.70 Wildlife and... in Certain Specimens § 23.70 How can I trade internationally in American alligator and other... section, crocodilian means all species of alligator, caiman, crocodile, and gavial of the order...

  5. 33 CFR 334.760 - Naval Support Activity Panama City and Alligator Bayou, a tributary of St. Andrew Bay, Fla...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... City and Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. 334.760 Section... Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. (a) The area. The waters within... the south side of the entrance to Alligator Bayou; thence directly across the entrance to a point...

  6. 50 CFR 23.70 - How can I trade internationally in American alligator and other crocodilian skins, parts, and...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... American alligator and other crocodilian skins, parts, and products? 23.70 Section 23.70 Wildlife and... in Certain Specimens § 23.70 How can I trade internationally in American alligator and other... section, crocodilian means all species of alligator, caiman, crocodile, and gavial of the order...

  7. 33 CFR 334.760 - Naval Support Activity Panama City and Alligator Bayou, a tributary of St. Andrew Bay, Fla...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... City and Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. 334.760 Section... Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. (a) The area. The waters within... the south side of the entrance to Alligator Bayou; thence directly across the entrance to a point...

  8. 33 CFR 334.760 - Naval Support Activity Panama City and Alligator Bayou, a tributary of St. Andrew Bay, Fla...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... City and Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. 334.760 Section... Alligator Bayou, a tributary of St. Andrew Bay, Fla.; naval restricted area. (a) The area. The waters within... the south side of the entrance to Alligator Bayou; thence directly across the entrance to a point...

  9. A new alligator-clip compound for molecular electronics

    NASA Astrophysics Data System (ADS)

    Jacob, Timo; Blanco, Mario; Goddard, William A.

    2004-06-01

    We used the B3LYP flavor of density functional calculations to study new alligator-clip compounds for molecular electronics with platinum electrodes. First, with commonly used S-based linkage molecule 3-methyl-1,2-dithiolane (MDTL) we find that after chemisorption on Pt(1 1 1) the most stable structure is ring-opened with a binding energy of 32.44 kcal/mol. Among several alternative alligator-clip compounds we find that P-based molecules lead to much higher binding energies. For the ring-closed structure of 3-methyl-1,2-diphospholane (MDPL) a binding energy of 47.72 kcal/mol was calculated and even 54.88 kcal/mol for the ring-opened molecule. Thus, MDPL provides a more stable link to the metal surface and might increase the conductance.

  10. Water Hyacinths and Alligator Weeds for Final Filtration of Sewage

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.; Gordon, J.

    1976-01-01

    The potential of water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxerides) (Mart.) Griesb. as secondary and tertiary filtration systems for domestic sewage was demonstrated. These two vascular aquatic plants reduced the suspended solids, total Kjeldahl nitrogen, total phosphorus, BOD sub 5, and total organic carbon levels in domestic sewage from 60 percent to 98 percent within a two week period. These plants grown in domestic sewage were also free of toxic levels of trace heavy metals.

  11. 78 FR 57480 - Safety Zone; 2013 Annual Islamorada Swim for Alligator Lighthouse, Atlantic Ocean; Islamorada, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ...) 366-9826. SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; 2013 Annual Islamorada Swim for Alligator... Islamorada, Florida, during the 2013 Annual Islamorada Swim for Alligator Lighthouse on September 21,...

  12. WILDLIFE - ALLIGATOR STROLLS FROM TURN BASIN TO LC 39 PRESS SITE GRANDSTAND

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A 12-foot alligator worked his way up from the turn basin at Press Site 39 to the grandstand seats. The toothy reptile was later wrangled by wildlife trappers who relocated him to a less populated area on KSC. The alligator is one of approximately 4,000 on KSC/Merritt Island National Wildlife Refuge.

  13. PLASMA STEROID CONCENTRATIONS IN RELATION TO SIZE AND AGE IN JUVENILE ALLIGATORS FROM TWO FLORIDA LAKES.

    EPA Science Inventory

    Previous studies have reported a number of physiological differences among juvenile alligators from two well-studied populations (Lake Apopka and Lake Woodruff) in north central Florida. These studies obtained alligators of similar size from each lake under the assumption that th...

  14. Alligators and Crocodiles Have High Paracellular Absorption of Nutrients, But Differ in Digestive Morphology and Physiology.

    PubMed

    Tracy, Christopher R; McWhorter, Todd J; Gienger, C M; Starck, J Matthias; Medley, Peter; Manolis, S Charlie; Webb, Grahame J W; Christian, Keith A

    2015-12-01

    Much of what is known about crocodilian nutrition and growth has come from animals propagated in captivity, but captive animals from the families Crocodilidae and Alligatoridae respond differently to similar diets. Since there are few comparative studies of crocodilian digestive physiology to help explain these differences, we investigated young Alligator mississippiensis and Crocodylus porosus in terms of (1) gross and microscopic morphology of the intestine, (2) activity of the membrane-bound digestive enzymes aminopeptidase-N, maltase, and sucrase, and (3) nutrient absorption by carrier-mediated and paracellular pathways. We also measured gut morphology of animals over a larger range of body sizes. The two species showed different allometry of length and mass of the gut, with A. mississippiensis having a steeper increase in intestinal mass with body size, and C. porosus having a steeper increase in intestinal length with body size. Both species showed similar patterns of magnification of the intestinal surface area, with decreasing magnification from the proximal to distal ends of the intestine. Although A. mississippiensis had significantly greater surface-area magnification overall, a compensating significant difference in gut length between species meant that total surface area of the intestine was not significantly different from that of C. porosus. The species differed in enzyme activities, with A. mississippiensis having significantly greater ability to digest carbohydrates relative to protein than did C. porosus. These differences in enzyme activity may help explain the differences in performance between the crocodilian families when on artificial diets. Both A. mississippiensis and C. porosus showed high absorption of 3-O methyl d-glucose (absorbed via both carrier-mediated and paracellular transport), as expected. Both species also showed surprisingly high levels of l-glucose-uptake (absorbed paracellularly), with fractional absorptions as high as those

  15. Organochlorine pesticides and thiamine in eggs of largemouth bass and American alligators and their relationship with early life-stage mortality

    USGS Publications Warehouse

    Sepulveda, M.S.; Wiebe, J.J.; Honeyfield, D.C.; Rauschenberger, H.R.; Hinterkopf, J.P.; Johnson, W.E.; Gross, T.S.

    2004-01-01

    Thiamine deficiency has been linked to early mortality syndrome in salmonids in the Great Lakes. This study was conducted to compare thiamine concentrations in American alligators (Alligator mississippiensis) and Florida largemouth bass (Micropterus salmoides floridanus) eggs from sites with high embryo mortality and high exposure to organochlorine pesticides (OCPs) (Lakes Apopka and Griffin, and Emeralda Marsh, Florida, USA) to those from sites that have historically exhibited low embryo mortality and low OCPs (Lakes Woodruff and Orange, Florida). During June-July 2000, 20 alligator clutches were collected from these sites, artificially incubated, and monitored for embryo mortality. Thiamine and OCPs were measured in one egg/clutch. During February 2002, 10 adult female bass were collected from Emeralda Marsh and Lake Woodruff and mature ovaries analyzed for thiamine and OCP concentrations. Although ovaries from the Emeralda Marsh bass contained almost 1,000-fold more OCPs compared with the reference site, Lake Woodruff, there were no differences in thiamine concentrations between sites (11,710 vs. 11,857 pmol/g). In contrast, alligator eggs from the reference site had five times the amount of thiamine compared with the contaminated sites (3,123 vs. 617 pmol/g). Similarly, clutches with > 55% hatch rates had significantly higher concentrations of thiamine compared with clutches with <54% hatch rates (1,119 vs. 201 pmol/g). These results suggest that thiamine deficiency might be playing an important role in alligator embryo survival but not in reproductive failure and recruitment of largemouth bass. The cause(s) of this thiamine deficiency are unknown but might be related to differences in the nutritional value of prey items across the sites studied and/or to the presence of high concentration of contaminants in eggs. ?? Wildlife Disease Association 2004.

  16. Dry years decrease abundance of American alligators in the Florida Everglades

    USGS Publications Warehouse

    Waddle, J. Hardin; Brandt, Laura A.; Jeffery, Brian M.; Mazzotti, Frank J.

    2015-01-01

    The Everglades has been greatly reduced and is threatened by land use change and altered hydrology. The Comprehensive Everglades Restoration Plan calls for monitoring and assessment of key ecosystem attributes, one of which is abundance of American alligators. We examined 10 years of alligator night spotlight counts from Arthur R. Marshall Loxahatchee National Wildlife Refuge along two canals and in the interior marsh to determine trends and how dry years affect alligator abundance. Alligators showed population response to hydrologic conditions. In particular, there were declines in abundance after dry years followed by an apparent recovery in abundance in subsequent years. Increases in abundance were lower in the marsh than L-40 Canal. In addition, there was evidence that intensity of dry events affected population dynamics with greater declines observed in years with drier conditions. Results revealed that overall population of alligators increased from 2004 to 2013, but that increases varied by survey route. These results demonstrate that dry years cause a decline in alligator abundance proportional to the intensity of the dry event, and that it is important to make a distinction between canals and marsh when measuring alligator response to hydrology.

  17. Traumatic Amputation of Finger From an Alligator Snapping Turtle Bite.

    PubMed

    Johnson, Robert D; Nielsen, Cynthia L

    2016-06-01

    Legend states that the alligator snapping turtle (Macrochelys temminckii) should be handled with extreme caution as it has jaw strength powerful enough to bite a wooden broomstick in half. Tales of bite injuries from what is the largest freshwater turtle in North America exist anecdotally, yet there are few descriptions of medical encounters for such. The risk of infection from reptilian bites to the hand in an aquatic environment warrants thorough antibiotic treatment in conjunction with hand surgery consultation. We present the first case report of a near total amputation of an index finger in an adolescent boy who had been bitten by a wild "gator snapper." PMID:27116923

  18. ALTERED HISTOLOGY OF THE THYMUS AND SPLEEN IN CONTAMINANT-EXPOSED JUVENILE AMERICAN ALLIGATORS

    EPA Science Inventory

    Morphological difference in spleen and thymus are closely related to functional immune differences. Hormonal regulation of the immune system has been demonstrated in reptilian splenic and thymic tissue. Spleens and thymus were obtained from juvenile alligators at two reference si...

  19. ALTERATIONS IN STEROIDOGENESIS IN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) EXPOSED NATURALLY AND EXPERIMENTALLY TO ENVIRONMENTAL CONTAMINANTS. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  20. THE REPRODUCTIVE CYCLE OF THE FEMALE AMERICAN ALLIGATOR (ALLIGATOR MISSISSIPPIENSIS). (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  1. Molecular cloning of the estrogen and progesterone receptors of the American alligator.

    PubMed

    Katsu, Yoshinao; Bermudez, Dieldrich S; Braun, Edward L; Helbing, Caren; Miyagawa, Shinichi; Gunderson, Mark P; Kohno, Satomi; Bryan, Teresa A; Guillette, Louis J; Iguchi, Taisen

    2004-03-01

    Steroid hormones perform many essential roles in vertebrates during embryonic development, reproduction, growth, water balance, and responses to stress. The estrogens are essential for normal reproductive activity in female and male vertebrates and appear to have direct actions during sex determination in some vertebrates. To begin to understand the molecular mechanisms of estrogen action in alligators, we have isolated cDNAs encoding the estrogen receptors (ER) from the ovary. Degenerate PCR primers specific to ER were designed and used to amplify alligator ovary RNA. Two different DNA fragments (ERalpha and ERbeta) were obtained and the full-length alligator ERalpha cDNA was obtained using 5' and 3' RACE. The inferred amino acid sequence of alligator ERalpha (aERalpha) was very similar to the chicken ERalpha (91% identity), although phylogenetic analyses suggested profound differences in the rate of sequence evolution for vertebrate ER sequences. We also isolated partial DNA fragments encoding ERbeta and the progesterone receptor (PR) of the alligator, both of which show strong sequence similarities to avian ERbeta and PR. We examined the expression levels of these three steroid receptors (ERalpha, ERbeta, and PR) in the ovary of juvenile alligators and observed detectable levels of all three receptors. Quantitative RT-PCR showed that gonadal ERalpha transcript levels in juvenile alligators decreased after E2 treatment whereas ERbeta and PR transcripts were not changed. These results provide tools that will allow future studies examining the regulation and ontogenic expression of steroid receptors in alligators and expand our knowledge of vertebrate steroid receptor evolution. PMID:14980803

  2. WILDLIFE - ALLIGATOR STRADDLES TWO PARKING SPACES IN FRONT OF OFFICE TRAILER

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Double-parked, an angry alligator straddles two parking spaces outside an office trailer at NASA's Launch Complex 17. Hank Curtin of Pan Am watches from a safe perch as John Tanner gets ready to wrap a rope around the snout of the 10-foot, 9-inch beast. It's all in a day's work for Tanner, who has a contract with the state of Florida to remove nuisance alligators.

  3. Alligator rivers analogue project an OECD/NEA international project

    SciTech Connect

    Duerden, P.; Airey, P.; Pescatore, C.

    1994-12-31

    The Koongarra uranium deposit in the Alligator Rivers Region of the Northern Territory of Australia was studied as a natural analogue of the far field behaviour of high level waste repositories following groundwater ingress. A number of mathematical modelling approaches were developed for processes as diverse as groundwater transport, host rock weathering, radionuclide sorption, evolution of the uranium dispersion fan and the distribution of uranium series nuclides between mineral assemblages in weathered host rock. Some of these models are relevant to performance assessment at the level of individual processes and subsystem performance. Through the project, new insights into the application of the natural analogue approach to the assessment of potential waste repository sites were obtained.

  4. Isolation and characterization of sulfite oxidase from Alligator mississipiensis

    SciTech Connect

    Robbins, A.; Neame, P.J.; Barber, M.J. )

    1991-03-11

    Sulfite oxidase has been isolated from fresh alligator liver using ammonium sulfate and acetone fractionation, DEAE chromatography and FPLC on Mono Q. The enzyme is dimeric and exhibits a subunit M. Wt. of approximately 58 kDa, larger than that of chicken SO. EPR spectroscopy of the partially-reduced enzyme revealed a single Mo(V) species while visible spectroscopy revealed the presence of cytochrome b{sub 557}. Maximal activities were obtained at pH 8 and 9, respectively. K{sub m}'s for SO{sub 3}{sup 2 {minus}}, cyt. c and Fe(CN){sub 6}{sup 3 {minus}} were 23.5 uM, 2.9 uM and 8.0 uM, respectively. Sequencing of peptides obtained by endoprotease K digestion indicated regions of extensive sequence similarity to chicken and rat enzymes in both heme and Mo-pterin domains. Regions of sequence dissimilarity were also found.

  5. A Chinese alligator in heliox: formant frequencies in a crocodilian

    PubMed Central

    Reber, Stephan A.; Nishimura, Takeshi; Janisch, Judith; Robertson, Mark; Fitch, W. Tecumseh

    2015-01-01

    ABSTRACT Crocodilians are among the most vocal non-avian reptiles. Adults of both sexes produce loud vocalizations known as ‘bellows’ year round, with the highest rate during the mating season. Although the specific function of these vocalizations remains unclear, they may advertise the caller's body size, because relative size differences strongly affect courtship and territorial behaviour in crocodilians. In mammals and birds, a common mechanism for producing honest acoustic signals of body size is via formant frequencies (vocal tract resonances). To our knowledge, formants have to date never been documented in any non-avian reptile, and formants do not seem to play a role in the vocalizations of anurans. We tested for formants in crocodilian vocalizations by using playbacks to induce a female Chinese alligator (Alligator sinensis) to bellow in an airtight chamber. During vocalizations, the animal inhaled either normal air or a helium/oxygen mixture (heliox) in which the velocity of sound is increased. Although heliox allows normal respiration, it alters the formant distribution of the sound spectrum. An acoustic analysis of the calls showed that the source signal components remained constant under both conditions, but an upward shift of high-energy frequency bands was observed in heliox. We conclude that these frequency bands represent formants. We suggest that crocodilian vocalizations could thus provide an acoustic indication of body size via formants. Because birds and crocodilians share a common ancestor with all dinosaurs, a better understanding of their vocal production systems may also provide insight into the communication of extinct Archosaurians. PMID:26246611

  6. A Chinese alligator in heliox: formant frequencies in a crocodilian.

    PubMed

    Reber, Stephan A; Nishimura, Takeshi; Janisch, Judith; Robertson, Mark; Fitch, W Tecumseh

    2015-08-01

    Crocodilians are among the most vocal non-avian reptiles. Adults of both sexes produce loud vocalizations known as 'bellows' year round, with the highest rate during the mating season. Although the specific function of these vocalizations remains unclear, they may advertise the caller's body size, because relative size differences strongly affect courtship and territorial behaviour in crocodilians. In mammals and birds, a common mechanism for producing honest acoustic signals of body size is via formant frequencies (vocal tract resonances). To our knowledge, formants have to date never been documented in any non-avian reptile, and formants do not seem to play a role in the vocalizations of anurans. We tested for formants in crocodilian vocalizations by using playbacks to induce a female Chinese alligator (Alligator sinensis) to bellow in an airtight chamber. During vocalizations, the animal inhaled either normal air or a helium/oxygen mixture (heliox) in which the velocity of sound is increased. Although heliox allows normal respiration, it alters the formant distribution of the sound spectrum. An acoustic analysis of the calls showed that the source signal components remained constant under both conditions, but an upward shift of high-energy frequency bands was observed in heliox. We conclude that these frequency bands represent formants. We suggest that crocodilian vocalizations could thus provide an acoustic indication of body size via formants. Because birds and crocodilians share a common ancestor with all dinosaurs, a better understanding of their vocal production systems may also provide insight into the communication of extinct Archosaurians. PMID:26246611

  7. Temporal profile of nerve growth factor expression in the partial central nervous system of the Yangtze alligator Alligator sinensis (Reptilia,Crocodylia) during early postnatal growth.

    PubMed

    Zheng, Lanrong; Chen, Fangfang; Wang, Renping; Zhou, Yongkang; Wu, Xiaobing

    2013-05-01

    Expression of nerve growth factor (NGF) in structures of the partial central nervous system of the Yangtze alligator, Alligator sinensis (Reptilia, Crocodylia) was examined during early postnatal growth using immunohistochemistry and Western blot assays. In animals 0-2 years of age NGF-positive cells in the cerebral cortex increased gradually in number and size, and were predominantly distributed in the molecular layer. NGF-positive cells in the midbrain showed similar increases but with predominant distribution in the ependymal layer. NGF-positive cells increased in the cerebellum between 0 and 1 years of age, with increased NGF expression being seen during the first 2 years of life mostly in the ependymal layer. NGF-positive cells were mainly found in the gray matter of the spinal cord with decreasing cell numbers, NGF expression levels being seen from 0 to 2 years and small processes without synaptic connection from 1 to 2 years. These results suggest that NGF is involved in the early postnatal growth of several structures of Yangtze alligator partial central nervous system, suggesting a possible role of NGF in the Yangtze alligator partial central nervous system. PMID:23504856

  8. Effect of alligator pepper (Zingiberaceae aframomum melegueta) on first trimester pregnancy in Sprague Dawley rats.

    PubMed

    Inegbenebor, U; Ebomoyi, M I; Onyia, K A; Amadi, K; Aigbiremolen, A E

    2009-12-01

    Alligator pepper (Aframomum melegueta) is a spice that is widely used in many cultures for entertainment, religious rites, food flavor and as a part of many traditional doctors medications. Pregnant women are among those who ingest Alligator pepper in these activities. This experiment was carried out to determine the health risk or benefit of Alligator pepper to pregnant women if any. Fifteen male rats and fifteen female rats of proven fertility from a pilot study were randomly paired in fifteen cages in a well ventilated room. After three days of mating, the males were withdrawn from the females, which were allowed to stay in their separate maternity cages for 18-25 days. The females in the control group were fed with normal rat chow and clean drinking water ad libitum for the duration of the experiment. Each of the rats in the experimental group was served 20 g of rat chow mixed with 50mg of Alligator pepper for one day only and thereafter fed with normal rat chow and clean drinking water ad libitum for 18-25 days. The rats in the control group had a mean of 7 litters each, while the rats in the experimental group did not litter at all. It was concluded that ingestion of large quantities of Alligator pepper poses a health risk to women in their first trimester of pregnancy. PMID:20234758

  9. Molecular cloning, characterization, tissue distribution and mRNA expression changes during the hibernation and reproductive periods of estrogen receptor alpha (ESR1) in Chinese alligator, Alligator sinensis.

    PubMed

    Zhang, Ruidong; Hu, Yuehong; Wang, Huan; Yan, Peng; Zhou, Yongkang; Wu, Rong; Wu, Xiaobing

    2016-10-01

    Chinese alligator, Alligator sinensis, is a critically endangered reptile species unique to China. Little is known about the mechanism of growth- and reproduction-related hormones gene expression in Chinese alligator. Estrogens play important roles in regulating multiple reproduction- and non-reproduction-related functions by binding to their corresponding receptors. Here, the full-length cDNA of estrogen receptor alpha (ERα/ESR1) was cloned and sequenced from Chinese alligator for the first time, which comprises 1764bp nucleotides and encodes a predicted protein of 587 amino acids. Phylogenetic analysis of ESR1 showed that crocodilians and turtles were the sister-group of birds. The results of real-time quantitative PCR indicated that the ESR1 mRNA was widely expressed in the brain and peripheral tissues. In the brain and pituitary gland, ESR1 was most highly transcribed in the cerebellum. But in other peripheral tissues, ESR1 mRNA expression level was the highest in the ovary. Compared with hibernation period, ESR1 mRNA expression levels were increased significantly in the reproductive period (P<0.05) in cerebellum, pituitary gland, liver, spleen, lung, kidney and ovary, while no significant change in other examined tissues (P>0.05). The ESR1 mRNA expression levels changes during the two periods of different tissues suggested that ESR1 might play an important role in mediation of estrogenic multiple reproductive effects in Chinese alligator. Furthermore, it was the first time to quantify ESR1 mRNA level in the brain of crocodilians, and the distribution and expression of ESR1 mRNA in the midbrain, cerebellum and medulla oblongata was also reported for the first time in reptiles. PMID:27212643

  10. Ontogeny of the Alligator Cartilago Transiliens and Its Significance for Sauropsid Jaw Muscle Evolution

    PubMed Central

    Tsai, Henry P.; Holliday, Casey M.

    2011-01-01

    The cartilago transiliens is a fibrocartilaginous structure within the jaw muscles of crocodylians. The cartilago transiliens slides between the pterygoid buttress and coronoid region of the lower jaw and connects two muscles historically identified as m. pseudotemporalis superficialis and m. intramandibularis. However, the position of cartilago transiliens, and its anatomical similarities to tendon organs suggest the structure may be a sesamoid linking a single muscle. Incompressible sesamoids often form inside tendons that wrap around bone. However, such structures rarely ossify in reptiles and have thus far received scant attention. We tested the hypothesis that the cartilago transiliens is a sesamoid developed within in one muscle by investigating its structure in an ontogenetic series of Alligator mississippiensis using dissection, 3D imaging, and polarizing and standard light microscopy. In all animals studied, the cartilago transiliens receives collagen fibers and tendon insertions from its two main muscular attachments. However, whereas collagen fibers were continuous within the cartilaginous nodule of younger animals, such continuity decreased in older animals, where the fibrocartilaginous core grew to displace the fibrous region. Whereas several neighboring muscles attached to the fibrous capsule in older individuals, only two muscles had significant contributions to the structure in young animals. Our results indicate that the cartilago transiliens is likely a sesamoid formed within a single muscle (i.e., m. pseudotemporalis superficialis) as it wraps around the pterygoid buttress. This tendon organ is ubiquitous among fossil crocodyliforms indicating it is a relatively ancient, conserved structure associated with the development of the large pterygoid flanges in this clade. Finally, these findings indicate that similar tendon organs exist among potentially homologous muscle groups in birds and turtles, thus impacting inferences of jaw muscle homology

  11. Antiglycation, antioxidant and toxicological potential of polyphenol extracts of alligator pepper, ginger and nutmeg from Nigeria

    PubMed Central

    Kazeem, MI; Akanji, MA; Hafizur, Rahman M; Choudhary, MI

    2012-01-01

    Objective To evaluate the antioxidant and antiglycation potential of polyphenols from three spices; alligator pepper, ginger and nutmeg. Methods Polyphenol extracts of these spices were subjected to brine-shrimp lethality assay, phytotoxicity test, DPPH and superoxide anion radical scavenging as well as BSA-glucose antiglycation assay. Results Results obtained showed that polyphenol extract of ginger has the highest antioxidant potential with IC50 0.075 and 0.070 mg/mL for DPPH and superoxide anion radical scavenging assay while alligator pepper displayed highest antiglycation activity with IC50 0.125 mg/mL. However, nutmeg extract exhibited weakest cytotoxic and phytotoxic potential with LD50 4359.70 and 1490 µg/mL respectively. Conclusions It can be concluded that the polyphenol extracts of alligator pepper, ginger and nutmeg displayed good antioxidant as well as antiglycation potential and are safe for consumption. PMID:23570003

  12. Dujardinascaris gigantea sp. n. (Nematoda: Ascaridida) from the critically endangered crocodile Alligator sinensis Fauvel (Reptilia: Crocodylia).

    PubMed

    Zhao, Jin-Hong; Li, Liang; Guo, Yan-Ning; Zhang, Lu-Ping

    2015-03-01

    The Chinese alligator Alligator sinensis Fauvel (Reptilia: Crocodylia) is considered as one of the most critically endangered species of the 23 extant crocodiles. However, our knowledge of the helminth parasites of this rare animal is completely lacking. During a helminthological survey of reptiles in China, we found a new ascaridoid nematode, Dujardinascaris gigantea sp. n. from A. sinensis. The morphology of D. gigantea sp. n. was studied using light and scanning electron microscopy. The new species was also characterised using molecular methods by sequencing and analysing the small ribosomal DNA (18S) and the second internal transcribed spacer (ITS-2). PMID:24924435

  13. Water hyacinths and alligator weeds for removal of silver, cobalt, and strontium from polluted waters

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1975-01-01

    Water hyacinths and alligator weeds demonstrated the ability to rapidly remove heavy metals from an aqueous system by root absorption and concentration. Water hyacinths demonstrated the ability to remove 0.439 mg of silver, 0.568 mg of cobalt, and 0.544 mg of strontium in an ionized form per gram of dry plant material in a 24-hour period. Alligator weeds removed a maximum of 0.439 mg of silver, 0.130 mg of cobalt, and 0.161 mg of strontium per gram of dry plant material per day.

  14. Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

    USGS Publications Warehouse

    Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank M; Cherkiss, Michael S.; Jeffery, Brian M.

    2013-01-01

    Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intrapopulation variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

  15. Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

    NASA Astrophysics Data System (ADS)

    Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael; Jeffery, Brian M.

    2013-12-01

    Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intra-population variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

  16. Follicle-stimulating hormone receptor (FSHR) in Chinese alligator, Alligator sinensis: molecular characterization, tissue distribution and mRNA expression changes during the female reproductive cycle.

    PubMed

    Zhang, Rui; Zhang, Shengzhou; Zhu, Xue; Zhou, Yongkang; Wu, Xiaobing

    2015-05-01

    The follicle-stimulating hormone (FSH) plays a central role in vertebrate reproduction, with the actions of FSH mediated by FSH receptors (FSHRs) on the granulosa cells of the ovary. The present study reports the cloning and characterization of FSHR in Chinese alligator, Alligator sinensis (caFSHR), and its tissue distribution and mRNA expression changes during the reproductive cycle. The mature protein of caFSHR displays typical features of the glycoprotein hormone receptor family, but also contains some remarkable differences when compared with other vertebrate FSHRs. The deduced amino acid sequence of the caFSHR shares identity of 85% with Chinese softshell turtle, 84-87% with birds, 77-78% with mammals, 67-73% with amphibians and 51-58% with fishes. Phylogenetic tree analysis of the FSHR amino acid sequence indicated that alligators cluster into the bird branch. Tissue expression analysis showed that caFSHR was not only expressed in the ovary, but also in the stomach, intestine, pancreas liver and oviduct at similar levels, while it was not detectable in heart, thymus or thyroid. Expression of caFSHR in the ovary is high in May (breeding prophase) and peaks in July during the breeding period, where it is maintained at high levels through September (breeding anaphase). Expression decreases significantly in November (hibernating period) and then remains relatively low from January to March (hibernating period). These temporal changes in FSHR expression suggest that it plays an important role in promoting ovarian development during the female reproductive cycle of Chinese alligator. PMID:25765682

  17. Simple solar technology saves money for alligator farms

    SciTech Connect

    Goldman, A.

    1993-01-01

    In 1990, a high-volume solar thermal water-heating system in Florida was installed in Okeechobee County by Solar Development, Inc. (SDI). The system is designed to provide large quantities of hot water for commercial use and heat water to as high as 140[degrees]F. The design in Florida is known as a Shallow Solar Pond (SSP). It was completed with the help of the Florida Alligator Farmers Association, the Florida Energy Office, Foster Farms, and SDI. The SSP is a modular system built on site and modified to meet the specific needs of each application. The tank and the collector are the same unit, which keeps the system cost very low. The typical SSP module is 16 feet wide and up to 200 feet long. The module contains one or two reinforced-rubber flat water bags similar to a water bed. The bags rest on a layer of insulation or sand inside concrete or fiberglass curbs. In the Foster Farms SSP, the insulation was omitted and the water bags are placed on sand. The bag is protected against damage and heat loss by greenhouse-type glazing. At Foster Farms there are 3 SSPs, set in approximately 8,000 square feet, with two 5,000-gallon bags per unit. In addition, there is a pressurizing pump/tank system. Every morning, the heated water from the bags drains into a sump tank. While the bags are emptied into the backup system, well water is pumped in and the solar heating process starts all over again.

  18. Effects of salinity on growth and ion regulation of juvenile alligator gar Atractosteus spatula.

    PubMed

    Schwarz, Daniel E; Allen, Peter J

    2014-03-01

    The alligator gar (Atractosteus spatula) is a primitive euryhaline fish, found primarily in estuaries and freshwater drainages associated with the northern Gulf of Mexico. The extent of its hypo-osmotic regulatory abilities is not well understood. In order to determine how salinity affects growth rates and ionic and osmoregulation, juvenile alligator gar (330 days after hatch; 185 g) were exposed to 4 different salinities (0, 8, 16, and 24 ppt) for a 30-day period. Specific growth rate, plasma osmolality and ion concentrations, gill and gastrointestinal tract Na(+), K(+)-ATPase activities, and drinking rate were compared. Juvenile alligator gar were able to tolerate hyperosmotic salinities up to 24 ppt for a 30 day period, albeit with decreased growth resulting largely from decreased food consumption. Plasma osmolality and ionic concentrations were elevated in hyperosmotic salinities, and drinking rates and gastrointestinal tract Na(+), K(+)-ATPase activities increased, particularly in the pyloric caeca, presumably the primary location of water absorption. Therefore, juvenile alligator gar<1 year of age are capable of prolonged exposure to hyperosmotic salinities, but, based on the inference of these data, require access to lower salinities for long-term survival. PMID:24368134

  19. A group of alligators basks in the sun and rest in the water at KSC.

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This pond near Schwartz Rd. at Kennedy Space Center is host to a least the nine alligators shown on the banks and in the water. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the Merritt Island National Wildlife Refuge, which shares a boundary with the Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  20. Effects of salinity on growth and ion regulation of juvenile alligator gar Atractosteus spatula

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The alligator gar (Atractosteus spatula) is a primitive euryhaline fish, found primarily in estuaries and freshwater drainages associated with the northern Gulf of Mexico. The extent of its hypo-osmotic regulatory abilities is not well understood. In order to determine how salinity affects growth ra...

  1. The evolutionary history of an invasive species: alligator weed, Alternanthera philoxeroides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The eco-evolutionary mechanisms of biological invasions are still not thoroughly understood. Alligator weed, Alternanthera philoxeroides (Martius) Gisebach (Amaranthaceae), is a plant native to South America and a weed in Australia and other countries. To better understand its success as an invader,...

  2. Evaluating recent taxonomic changes for alligator snapping turtles (Testudines: Chelydridae).

    PubMed

    Folt, Brian; Guyer, Craig

    2015-01-01

    The Alligator Snapping Turtle (Macrochelys temminckii Troost in Harlan 1835, sensu lato) has been historically treated as a single, wide-ranging species, until a recently published paper by Thomas et al. (2014; hereafter Thomas et al.) analyzed variation in morphology and mitochondrial DNA sequence data to describe two new species of Macrochelys: the Apalachicola Alligator Snapping Turtle (Macrochelys apalachicolae Thomas, Granatosky, Bourque, Krysko, Moler, Gamble, Suarez, Leone & Roman 2014) and the Suwannee Alligator Snapping Turtle (Macrochelys suwanniensis Thomas, Granatosky, Bourque, Krysko, Moler, Gamble, Suarez, Leone & Roman 2014). The specific epithet temminckii was retained for populations in drainages from the Yellow River in Alabama and Florida west to the San Antonio River, Texas. Because populations of Macrochelys have been historically exploited by humans (Pritchard 1989) and the life-history strategies of large, long-lived turtles make them susceptible to declines from harvest (Congdon et al. 1994), a sound understanding of species delimitation and richness is critical for the conservation of alligator snapping turtles, especially if the acceptance of a widely distributed species disguises the presence of multiple, smaller-ranged species. PMID:25947748

  3. Isolation and expression of a novel alligator gene belonging to the Sox gene family.

    PubMed

    Zheng, Jifang; Hu, Nan; Zhu, Muyuan; Nu, Yaqing; Liu, Zhen

    2009-02-01

    Sox genes share a highly conserved DNA-binding motif, the HMG (high mobility group)-box domain, and have diverse roles in vertebrate embryonic development. A novel SRY-related cDNA (temporarily called Sox33) isolated from the Chinese alligator (Alligator sinensis) is 1,819 bp in length, with an open reading frame from 220 to 1113 bp, encoding a protein of 298 amino acids. Two putative polyadenylation signal sequences (AATAAA) are present upstream of the poly(A) tail in the 3' UTR (at 1255-1260 and 1774-1779). The putative protein contains an HMG-box domain most closely related to hSox12, mSox4, rtSox11, and mSox11 homologs, indicating that alligator Sox33 belongs to group C in the Sox gene family. Alligator adult and developing tissues were tested for Sox33 mRNA by independent Northern blots using a 336-bp probe (at 907-1243) between the HMG-box and the poly(A) site I and a 277-bp probe (at 1477-1754) between the two polyadenylation sites. Two transcripts (1.3 kb and 1.8 kb) in developing brain and one (1.8 kb) in adult brain were identified by the 336-bp probe; only one transcript (1.8 kb) in developing and adult brains was detected by the 277-bp probe. The results suggest that alligator Sox33 may use a different polyadenylation mechanism in the developing brain and play a role in the development and maintenance of the nervous system. PMID:19169861

  4. Genome analysis and signature discovery for diving and sensory properties of the endangered Chinese alligator

    PubMed Central

    Wan, Qiu-Hong; Pan, Sheng-Kai; Hu, Li; Zhu, Ying; Xu, Peng-Wei; Xia, Jin-Quan; Chen, Hui; He, Gen-Yun; He, Jing; Ni, Xiao-Wei; Hou, Hao-Long; Liao, Sheng-Guang; Yang, Hai-Qiong; Chen, Ying; Gao, Shu-Kun; Ge, Yun-Fa; Cao, Chang-Chang; Li, Peng-Fei; Fang, Li-Ming; Liao, Li; Zhang, Shu; Wang, Meng-Zhen; Dong, Wei; Fang, Sheng-Guo

    2013-01-01

    Crocodilians are diving reptiles that can hold their breath under water for long periods of time and are crepuscular animals with excellent sensory abilities. They comprise a sister lineage of birds and have no sex chromosome. Here we report the genome sequence of the endangered Chinese alligator (Alligator sinensis) and describe its unique features. The next-generation sequencing generated 314 Gb of raw sequence, yielding a genome size of 2.3 Gb. A total of 22 200 genes were predicted in Alligator sinensis using a de novo, homology- and RNA-based combined model. The genetic basis of long-diving behavior includes duplication of the bicarbonate-binding hemoglobin gene, co-functioning of routine phosphate-binding and special bicarbonate-binding oxygen transport, and positively selected energy metabolism, ammonium bicarbonate excretion and cardiac muscle contraction. Further, we elucidated the robust Alligator sinensis sensory system, including a significantly expanded olfactory receptor repertoire, rapidly evolving nerve-related cellular components and visual perception, and positive selection of the night vision-related opsin and sound detection-associated otopetrin. We also discovered a well-developed immune system with a considerable number of lineage-specific antigen-presentation genes for adaptive immunity as well as expansion of the tripartite motif-containing C-type lectin and butyrophilin genes for innate immunity and expression of antibacterial peptides. Multifluorescence in situ hybridization showed that alligator chromosome 3, which encodes DMRT1, exhibits significant synteny with chicken chromosome Z. Finally, population history analysis indicated population admixture 0.60-1.05 million years ago, when the Qinghai-Tibetan Plateau was uplifted. PMID:23917531

  5. IgH loci of American alligator and saltwater crocodile shed light on IgA evolution.

    PubMed

    Magadán-Mompó, Susana; Sánchez-Espinel, Christian; Gambón-Deza, Francisco

    2013-07-01

    Immunoglobulin loci of two representatives of the order Crocodylia were studied from full genome sequences. Both Alligator mississippiensis and Crocodylus porosus have 13 genes for the heavy chain constant regions of immunoglobulins. The IGHC locus contains genes encoding four immunoglobulins M (IgM), one immunoglobulin D (IgD), three immunoglobulins A (IgA), three immunoglobulins Y (IgY), and two immunoglobulins D2 (IgD2). IgA and IgD2 genes were found in reverse transcriptional orientation compared to the other Ig genes. The IGHD gene contains 11 exons, four of which containing stop codons or sequence alterations. As described in other reptiles, the IgD2 is a chimeric Ig with IgA- and IgD-related domains. This work clarifies the origin of bird IgA and its evolutionary relationship with amphibian immunoglobulin X (IgX) as well as their links with mammalian IgA. PMID:23558556

  6. The oldest record of Alligator sinensis from the Late Pliocene of Western Japan, and its biogeographic implication

    NASA Astrophysics Data System (ADS)

    Iijima, Masaya; Takahashi, Keiichi; Kobayashi, Yoshitsugu

    2016-07-01

    The late Cenozoic fossil record of alligators in East Asia is crucial in understanding the origin and past distribution of Asian alligators that are now represented by a single species, Alligator sinensis. This study reports a partial skeleton of A. sinensis from the Late Pliocene (approximately 3.0 Ma) of western Japan. This Japanese A. sinensis is large in size (>200 cm total length), comparable to the maximum size of extant individuals. It demonstrates the oldest record of A. sinensis and wider distribution of this species in the past. Tectonic and geographic history of East Asia suggests that alligators presumably dispersed into Japan before 25 Ma or after 10 Ma, yet finally were wiped out from Japan due to the semi-isolated condition of the Japanese island arc and the deteriorated climate during the Plio-Pleistocene.

  7. EAARL coastal topography--Alligator Point, Louisiana, 2010

    USGS Publications Warehouse

    Nayegandhi, Amar; Bonisteel-Cormier, J.M.; Wright, C.W.; Brock, J.C.; Nagle, D.B.; Vivekanandan, Saisudha; Fredericks, Xan; Barras, J.A.

    2012-01-01

    This project provides highly detailed and accurate datasets of a portion of Alligator Point, Louisiana, acquired on March 5 and 6, 2010. The datasets are made available for use as a management tool to research scientists and natural-resource managers. An innovative airborne lidar instrument originally developed at the National Aeronautics and Space Administration (NASA) Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multispectral color-infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for sub-meter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine aircraft, but the instrument was deployed on a Pilatus PC-6. A single pilot, a lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom-built processing system developed in a NASA-USGS collaboration. ALPS supports the exploration and processing of lidar data in an interactive or batch mode. Modules for presurvey flight-line definition, flight-path plotting, lidar raster and waveform investigation, and digital camera image playback have been developed. Processing algorithms have

  8. Herpetofaunal diversity of Alligator River National Wildlife Refuge, North Carolina

    USGS Publications Warehouse

    Meyers, J.M.; Pike, D.A.

    2006-01-01

    In the past century, habitat alteration and fragmentation have increased dramatically, which increases the need for improving our understanding of how species and biological communities react to these modifications. A national strategy on biological diversity has focused attention on how these habitat modifications affect species, especially herpetofauna (i.e., changes in species richness, community evenness and similarity, and dominant/rare species). As part of this strategy, we surveyed Alligator River National Wildlife Refuge, a coastal, mixed second-growth forested swamp (MFS) and pocosin wetland (PW), in North Carolina for amphibians and reptiles from September 2000 to August 2001. We randomly selected three sites (3 x 3 km) in two major habitat types (MFS, PW) and completed random surveys and trapping using transects, quadrats, nighttime aural road surveys, drift fences, canal transects, coverboards, incidental captures, and evening road surveys. We also collected herpetofauna opportunistically throughout the refuge to establish an updated species list. For analysis, we used Shannon-Weiner species diversity (H'), evenness (1'), species richness and species detectability (COMDYN4), and community percent similarity index to determine herpetofaunal community differences. We estimated 39 species in MFS and 32 species in PW (P < 0.10). Species detectability was similar between habitats (0.84 to 0.86). More reptilian species (+ 31 %) inhabited MFS than PW, but estimated amphibian species richness was identical (17 spp.). H' was higher (P < 0.000 I) for PW (2.6680) than for MFS (2.1535) because of lower J' in the latter (0.6214 vs. 0.8010). Dominance of three Rana species caused lower J' and H' in MFS. Similarity between the communities was 56.6%; we estimated 22-24 species in common for each habitat (95% CI = 18 to 31 spp.). We verified 49 of the 52 herpetofaunal species on the refuge that were known to exist in the area. Restoration of natural water flows may

  9. Hydrodynamic analysis, performance assessment, and actuator design of a flexible tail propulsor in an artificial alligator

    NASA Astrophysics Data System (ADS)

    Philen, Michael; Neu, Wayne

    2011-09-01

    The overall objective of this research is to develop analysis tools for determining actuator requirements and assessing viable actuator technology for design of a flexible tail propulsor in an artificial alligator. A simple hydrodynamic model that includes both reactive and resistive forces along the tail is proposed and the calculated mean thrust agrees well with conventional estimates of drag. Using the hydrodynamic model forces as an input, studies are performed for an alligator ranging in size from 1 cm to 2 m at swimming speeds of 0.3-1.8 body lengths per second containing five antagonistic pairs of actuators distributed along the length of the tail. Several smart materials are considered for the actuation system, and preliminary analysis results indicate that the acrylic electroactive polymer and the flexible matrix composite actuators are potential artificial muscle technologies for the system.

  10. Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1975-01-01

    Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to remove a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period.

  11. Determining the size of American alligators using hind-foot track length

    USGS Publications Warehouse

    Wilkinson, Philip M.; Rice, Kenneth G.

    2000-01-01

    Size distribution information is useful for crocodilian management, but can be hard to obtain. Indirect and less costly demographic inferences made from track measurements may be valuable for management decisions. We related hind-foot lengths (HF) with total length (TL) to determine if we could indirectly assess alligator size using track length. Regression showed that HF was an excellent predictor (F1,246= 15722.9, R2=0.98, P<0.01) of TL and track length was an exceptional predictor of HF (F1,14=7520.3, R2= 1.00, P<0.01). The correlation between track length and HF length also was significant (N= 15, r=0.99, P <0.01). Thus, alligator size can be accurately estimated from measures of track length at sites where capture and direct measurement is impractical.

  12. WILDLIFE - ALLIGATOR NAMED KASEY LIVES IN POND IN FRONT OF HEADQUARTERS

    NASA Technical Reports Server (NTRS)

    1969-01-01

    A big, toothy saurian grin is flashed by this alligator in the pond in front of the KSC Headquarters Building. And wy not? After years of namelessness, he [or she] has a name. The 'gator was dubbed Kasey following a ''Name the Gator'' contest in which scores of Spaceport employees submitted name suggestions. Kasey is one of two 'gators placed in the pond in an attempt to restore its natural ecology.

  13. Biosorption of As(V) onto dried alligator weed root: role of metal (hydro) oxides.

    PubMed

    Chen, Jian; Tao, Weihua; Sun, Cheng

    2016-01-01

    The present work investigates the adsorption of As(V) onto the dried powder of alligator weed root as bio-sorbent, using acid pre-treated alligator weed root powder as the reference. The isotherm study suggested there is a favorable As(V) adsorption happened on the AWR surface. The batch adsorption experimental results indicated that the ionic strength has little impact on the adsorption, while the solution pH has a significant effect on the adsorption with apparent inhibition appearing in both extreme acidic and alkaline pH region. In addition, the properties of the biosorbent were characterized by various techniques including SEM-EDS, FT-IR, and ICP detection. The analysis results suggested that the metals including Mn, Fe, and Al enrich over the alligator weed root surface in the morphology of metal (hydro) oxide. Based on the nature of the biosorbent and As(V) besides the adsorption performance, the metal (hydro) oxides over biosorbent surface is suggested as the essential role to drive the adsorption. With the metal (hydro) oxides denuded in the pre-treatment, the biosorbent loses its adsorption capability for As(V) totally. PMID:26458188

  14. Analysis of the landsat remote sensing images of the types of habitats of Yangtze alligators

    NASA Astrophysics Data System (ADS)

    Huang, Zhujian; Lin, Hengzhang; Zhang, Shengkai

    1986-12-01

    The Chinese “Yangtze” alligator is a rare reptile that has been listed as an “endangered species” by the United Nations, so its preservation has become an urgent task. A study of its habitats through analysis of their Landsat images will provide a scientific basis for the government departments concerned to select the best locations for its breeding. The Chinese alligator is a subtropical reptile of freshwater rivers, lakes and ponds. Found only in China, it is now distributed only in the border region between the three provinces of Anhui, Zhejiang and Jiangsu. On the basis of previous investigations by Chinese scientists, and from an analysis and interpretation of their Landsat images, we made a special study, review, and classification of the natural environment of the alligator’s present habitats (and the modern changes in the natural background of these hatitats) so that the government departments concerned with the preservation of the reptiles may have a scientific basis for determining the best locations for the breeding and propagation of the alligator.

  15. ALTERATIONS IN SEXUALLY DIMORPHIC BIOTRANSFORMATION OF TESTOSTERONE IN JUVENILE AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED LAKES. (R826129)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  16. SEX-STEROID AND THYROID HORMONE CONCENTRATIONS IN JUVENILE ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED AND REFERENCE LAKES IN FLORIDA, USA

    EPA Science Inventory

    Sex-steroid and thyroid hormones are critical regulators of growth and reproduction in all vertebrates, and several recent studies suggest that environmental chemicals can alter circulating concentrations of these hormones. This study examines plasma concentrations of estradiol-...

  17. IDENTIFICATION AND CHARACTERIZATION OF ESTROGEN AND PROGESTERONE RECEPTORS FROM THE OVIDUCT OF THE AMERICAN ALLIGATOR (ALLIGATOR MISSISSIPPIENSIS). (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  18. Full-length cDNA cloning and structural characterization of preproinsulin in Alligator sinensis.

    PubMed

    Zhang, R; Zhang, S Z; Li, E; Wang, C; Wang, C L; Wu, X B

    2014-01-01

    Insulin is an important endocrine hormone that plays a critical physiological role in regulating metabolism and glucostasis in vertebrates. In this study, the complete cDNA of Alligator sinensis preproinsulin gene was cloned for the first time by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends methods; the amino acid sequence encoded and protein structure were analyzed. The full-length of preproinsulin cDNA sequence consists of 528 base pairs (bp), comprising a 34-bp 5'-untranslated region, a 170-bp 3'-untranslated region and an open reading frame that is 324 bp in length. The open reading frame encodes a 107-amino acid preproinsulin with a molecular weight of approximately 12,153.8 Da, theoretical isoelectric point of 5.68, aliphatic index of 92.06, and grand average of hydropathicity of -0.157, from which a signal peptide, a B-chain, a C-peptide, and an A-chain are derived. Online analysis suggested that the deduced preproinsulin amino acid sequence contains a transmembrane region, and that it has a signal peptide whose cleavage site occurs between alanine 24 and alanine 25. Comparative analysis of preproinsulin amino acid sequences indicated that the A-chain and B-chain sequences of preproinsulins are highly conserved between reptiles and birds, and that the preproinsulin amino acid sequence of Alligator sinensis shares 89% similarity to that of Chelonia mydas, but low similarity of 48-63% to those of mammals and fishes. The phylogenetic tree constructed using the neighbor-joining method revealed that preproinsulin of Alligator sinensis had high homology with reptiles and birds, such as Chelonia mydas, Gallus gallus, and Columba livia. PMID:25366775

  19. Plasma steroid concentrations and male phallus size in juvenile alligators from seven Florida lakes

    USGS Publications Warehouse

    Guillette, L.J., Jr.; Woodward, A.R.; Crain, D.A.; Pickford, D.B.; Rooney, A.A.; Percival, H.F.

    1999-01-01

    Neonatal and juvenile alligators from contaminated Lake Apopka in central Florida exhibit abnormal plasma sex steroid concentrations as well as morphological abnormalities of the gonad and phallus. This study addresses whether similar abnormalities occur in juvenile alligators inhabiting six other lakes in Florida. For analysis, animals were partitioned into two subsets, animals 40-79 cm total length (1-3 years old) and juveniles 80-130 cm total length (3-7 years old). Plasma testosterone (T) concentrations were lower in small males from lakes Apopka, Griffin, and Jessup than from Lake Woodruff National Wildlife Refuge (NWR). Similar differences were observed in the larger juveniles, with males from lakes Jessup, Apopka, and Okeechobee having lower plasma T concentrations than Lake Woodruff males. Plasma estradiol-17?? (E2) concentrations were significantly elevated in larger juvenile males from Lake Apopka compared to Lake Woodruff NWR. When compared to small juvenile females from Lake Woodruff NWR, females from lakes Griffin, Apopka, Orange, and Okeechobee had elevated plasma E2 concentrations. Phallus size was significantly smaller in males from lakes Griffin and Apopka when compared to males from Lake Woodruff NWR. An association existed between body size and phallus size on all lakes except Lake Apopka and between phallus size and plasma T concentration on all lakes except lakes Apopka and Orange. Multiple regression analysis, with body size and plasma T concentration as independent covariables, explained the majority of the variation in phallus size on all lakes. These data suggest that the differences in sex steroids and phallus size observed in alligators from Lake Apopka are not limited to that lake, nor to one with a history of a major pesticide spill. Further work examining the relationship of sex steroids and phallus size with specific biotic and abiotic factors, such as antiandrogenic or estrogenic contaminants, is needed.

  20. DIFFERENCES IN SENSITIVITY BUT NOT SELECTIVITY OF XENOESTROGEN BINDING TO ALLIGATOR VERSUS HUMAN ESTROGEN RECEPTOR ALPHA

    PubMed Central

    Rider, Cynthia V.; Hartig, Phillip C.; Cardon, Mary C.; Lambright, Christy R.; Bobseine, Kathy L.; Guillette, Louis J.; Gray, L. Earl; Wilson, Vickie S.

    2010-01-01

    Reproductive abnormalities in alligators exposed to contaminants in Lake Apopka, Florida, USA represent a clear example of endocrine disruption in wildlife. Several of these contaminants that are not able to bind to mammalian estrogen receptors (such as atrazine and cyanazine) have previously been reported to bind to the alligator estrogen receptor from oviductal tissue. Binding of known Lake Apopka contaminants to full length estrogen receptors alpha from human (hERα) and alligator (aERα) was assessed in a side-by-side comparison within the same assay system. Baculovirus-expressed recombinant hERα and aERα were used in a competitive binding assay. Atrazine and cyanazine were not able to bind to either receptor. p,p′-Dicofol was able to bind to aERα with a concentration inhibiting 50% of binding (IC50) of 4 μM, while only partially displacing 17β-estradiol (E2) from hERα and yielding a projected IC50 of 45 μM. Chemicals that only partially displaced E2 from either receptor, including some dichlorodiphenyltrichloroethane (DDT) metabolites and trans-nonachlor, appeared to have higher affinity for aERα than hERα. p,p′-Dicofol-mediated transcriptional activation through aERα and hERα was assessed to further explore the preferential binding of p,p′-dicofol to aERα over hERα. p,p′-Dicofol was able to stimulate transcriptional activation in a similar manner with both receptors. However, the in vitro results obtained with p,p′-dicofol were not reflected in an in vivo mammalian model, where Kelthane™ (mixed o,p′-and p,p′-dicofol isomers) did not elicit estrogenic effects. In conclusion, although there was no evidence of exclusively species-specific estrogen receptor binders, some xenoestrogens, especially p,p′-dicofol, had a higher affinity for aERα than for hERα. PMID:20821664

  1. Physiological response of alligator gar juveniles (Atractosteus spatula) exposed to sub-lethal doses of pollutants.

    PubMed

    González, Carlos Aguilera; Cruz, Julio; Alfaro, Roberto Mendoza

    2015-08-01

    Alligator gar populations have declined because of overfishing, habitat loss and pollution. Over time, the exposure to different pollutants have affected these fishes as a consequence of their high trophic level, bottom-dwelling habits and long life span. In order to evaluate the physiological effects of pollutants on alligator gar, juveniles (6, 12 and 24 months) were exposed to sub-lethal doses of diazinon, β-naphthoflavone (BNF) and 17 β-estradiol (E2) by intraperitoneal injection. After 2 days of exposure, liver samples were taken to determine the activities of acetylcholinesterase, butyrylcholinesterase and carboxylesterase; alkaline and acid phosphatases (ALP and ACP); ethoxyresorufin o-deethylase (EROD); glutathione s-transferase (GST); superoxide dismutase (SOD), and vitellogenin (VTG) concentration. Two additional bioassays consisting on the exposure of compounds through water or food were performed and after 4 and 28 days, respectively, biomarkers were determined. All esterases were inhibited in organisms exposed to diazinon as well as in 6-months gar exposed to E2 and BNF. In contrast, ALP activity increased in gar exposed to diazinon and E2, while ACP activity did not show any variations. No EROD activity was registered after exposure to the different pollutants, despite being one of the most sensitive and common detoxification biomarkers used for fishes. GST activity reduction was detected when gar were exposed to E2 and BNF, while SOD activity increased after exposure to diazinon and E2. Finally, VTG levels were higher in animals exposed to E2 compared to other treatments. Overall, these results suggest that alligator gar juveniles have a low biotransformation metabolism and show that they are especially sensitive to those pollutants affecting the nervous system. PMID:25948055

  2. Environmental risk assessment of compost prepared from salvinia, egeria densa, and alligator weed.

    PubMed

    Dorahy, C G; Pirie, A D; McMaster, I; Muirhead, L; Pengelly, P; Chan, K Y; Jackson, M; Barchia, I M

    2009-01-01

    Approximately 70,000 m(3) of salvinia (Salvinia molesta) was removed from the Hawkesbury-Nepean River, New South Wales (NSW), Australia, during 2004. This study assessed the risks associated with applying compost prepared from aquatic weeds (AWC) to land, namely, survival and spread of aquatic and terrestrial weeds, eutrophication of waterways, accumulation of heavy metals and phytotoxicity. The results demonstrate composting is an effective method of reducing the viability of aquatic and terrestrial weeds. However, mortality of alligator weed (Alternanthera philoxeroides), which was used as an indicator plant, was significantly (P < 0.001) correlated with the temperature within the windrows and the length of time the material was subjected to composting. Conditions within the central core of the windrow were sufficient to kill the alligator weed, although not all of the aquatic weed material was exposed to the windrows' central core. This resulted in alligator weed continuing to grow at the base of the windrow. To reduce the risk of weeds surviving and spreading in aquatic and terrestrial environments it is suggested compost windrows should be located on an appropriate hard pad to enable complete mixing of the material and ensure all material is exposed to temperatures >55 degrees C for greater than three consecutive days. The likelihood of other risks associated with the AWC was low. If composting is selected as the preferred method for managing organic material harvested from waterways, then ongoing monitoring and evaluation is required to validate the composting process and ensure consumer confidence in the final product. PMID:19465724

  3. Characterization of microsatellite DNA markers for the alligator snapping turtle, Macrochelys temminckii: Primer note

    USGS Publications Warehouse

    Hackler, J.C.; Van Den Bussche, Ronald A.; Leslie, David M., Jr.

    2007-01-01

    Two trinucleotide and seven tetranucleotide microsatellite loci were isolated from an alligator snapping turtle Macrochelys temminckii. To assess the degree of variability in these nine microsatellite loci, we genotyped 174 individuals collected from eight river drainage basins in the southeastern USA. These markers revealed a moderate degree of allelic diversity (six to 16 alleles per locus) and observed heterozygosity (0.166-0.686). These polymorphic microsatellite loci provide powerful tools for population genetic studies for a species that is afforded some level of conservation protection in every state in which it occurs. ?? 2006 The Authors.

  4. Urinary iodine and stable isotope analysis to examine habitat influences on thyroid hormones among coastal dwelling American alligators.

    PubMed

    Boggs, Ashley S P; Hamlin, Heather J; Nifong, James C; Kassim, Brittany L; Lowers, Russell H; Galligan, Thomas M; Long, Stephen E; Guillette, Louis J

    2016-01-15

    The American alligator, generally a freshwater species, is known to forage in marine environments despite the lack of a salt secreting gland found in other crocodylids. Estuarine and marine foraging could lead to increased dietary uptake of iodine, a nutrient necessary for the production of thyroid hormones. To explore the influence of dietary iodine on thyroid hormone health of coastal dwelling alligators, we described the seasonal plasma thyroxine and triiodothyronine concentrations measured by radioimmunoassay and urinary iodine (UI) concentrations measured by inductively coupled plasma mass spectrometry. We also analyzed long-term dietary patterns through stable isotope analysis of scute tissue. Snout-to-vent length (SVL) was a significant factor among UI and stable isotope analyses. Large adult males greater than 135cm SVL had the highest UI concentrations but did not display seasonality of thyroid hormones. Alligators under 135 SVL exhibited seasonality in thyroid hormones and a positive relationship between UI and triiodothyronine concentrations. Isotopic signatures provided supporting evidence that large males predominantly feed on marine/estuarine prey whereas females showed reliance on freshwater/terrestrial prey supplemented by marine/estuarine prey. UI measurement provided immediate information that correlated to thyroid hormone concentrations whereas stable isotope analysis described long-term dietary patterns. Both techniques demonstrate that adult alligators in coastal environments are utilizing estuarine/marine habitats, which could alter thyroid hormone physiology. PMID:26684734

  5. Potential impact of Dare County landfills on Alligator River National Wildlife Refuge

    USGS Publications Warehouse

    Winger, P.V.; Lasier, P.J.; Augspurger, T.

    2005-01-01

    Runoff of leachate from East Lake and Dare County Construction and Demolition Debris landfills has the potential to impact wildlife resources at Alligator River National Wildlife Refuge, Dare and Hyde Counties, North Carolina. Sediment quality of samples collected in August 2000 at 14 locations down-gradient from the landfills was assessed by measuring metal and organic contaminants in the sediments, chronic toxicity of solid-phase sediment (28-d static-renewal exposures; survival and growth as test endpoints) and acute toxicity of sediment porewater (96-h static exposures) to Hyalella azteca (Crustacea: Amphipoda). In addition, contaminant bioaccumulation from 4 sediments was determined using 28-d exposures of Lumbriculus variegatus (freshwater oligochaete). Although survival was not impaired, length of H. azteca was significantly reduced in sediments from 5 locations. Pore water from 4 locations was acutely toxic to H. azteca. Metals and a few polycyclic aromatic hydrocarbons (PAHs) were bioaccumulated by L. variegatus from the sediments. Several metals and PAHs exceeded sediment quality guidelines, and metals in porewater from several sites exceeded water quality criteria for the protection of aquatic wildlife. Runoff of leachate from the landfills has reduced sediment quality and has the potential to adversely affect wildlife resources at Alligator River National Wildlife Refuge.

  6. Study of red-sore disease in alligators. Final report, September 1, 1976-September 3, 1980. [Predisposing factors

    SciTech Connect

    Gorden, R.E.; Esch, G.W.

    1980-01-01

    Necropsies of eight alligators which died following capture within a thermally-altered reservoir demonstrated the presence of the gram negative, pathogenic bacterium Aeromonas hydrophila, in internal tissues. A study designed to demonstrate whether A. hydrophila were capable of causing infection and death of the ecologically threatened alligator and, if so, the mechanism of exposure and infection in natural habitats was undertaken. The pathology and response to infection were also studied. When juvenile alligators were exposed under experimental conditions to increasing concentrations of A. hydrophila in water, by oral inoculation, or by intramuscular injections at 20/sup 0/, 25/sup 0/, 30/sup 0/, and 35/sup 0/C, they developed external lesions. These lesions were likely to become severe and lead to death of the animal at 30 and 35/sup 0/C. Infected animals produced: (a) increased numbers of white blood cells; (b) increased specific antibody titer; and (c) alpha 2 peaks higher than albumen peaks (except at 35/sup 0/C). Biweekly intraperitoneal injections of live, washed A. hydrophila were apparently more effective in the prevention of infection and of external lesions than were the antibiotics Kanamycin and OTH-Puramycin. Topical applications of Neosporin ointment resulted in the healing of severe lesions on confined animals. Alligators which were shown to be exposed to A. hydrophila in their natural habitats showed no external evidence of infection by the bacteria. It is recommended that exposure to conditions of stress, including water temperatures greater than 30/sup 0/C, be kept to a minimum during the capture, transport, and captivity of alligators. (ERB)

  7. EFFECT OF ACUTE STRESS ON PLASMA CONCENTRATIONS OF SEX AND STRESS HORMONES IN JUVENILE ALLIGATORS LIVING IN CONTROL AND CONTAMINATED LAKES

    EPA Science Inventory

    Environmental contaminants can act as stressors, inducing elevated circulating concentrations of stress hormones such as corticosterone and cortisol. Development in contaminated eggs has been reported to modify circulating sex steroid hormone concentrations in alligators (Alligat...

  8. THE FUNCTIONAL AND STRUCTURAL OBSERVATIONS OF THE NEONATAL REPRODUCTIVE SYSTEM OF ALLIGATORS EXPOSED IN OVO TO ATRAZINE, 2,4-D, OR ESTRADIOL.

    EPA Science Inventory

    Wild alligators exposed to persistent organochlorine contaminants, municipal waste compounds, and contemporary-use herbicides exhibit reproductive alterations that are thought to be caused by endocrine disruption. This study tests the hypothesis that these alterations, at least i...

  9. Guidelines for choosing molecular "alligator clip" binding motifs in electron transport devices

    NASA Astrophysics Data System (ADS)

    Reuter, Matthew G.; Seideman, Tamar; Ratner, Mark A.

    2011-04-01

    We employ a one-electron, tight-binding model of an electrode-molecule-electrode junction to explore the fundamental relationship between adsorption geometry and electron transport, producing exact results (within this model). By varying the chemisorption location (e.g., atop a surface atom or in a hollow site between surface atoms) and the molecule-electrode coupling, we find that the largest currents are realized when the molecule (i) is highly coordinated by the surface and (ii) has favorable overlap with electrode states near the Fermi level. We also show the importance of electrode-induced molecular level shifting for certain adsorption geometries, which can cause molecular levels far from the Fermi level to conduct better than those near the Fermi level. Since all of these factors are greatly influenced by the chemical moiety used to link the molecule to an electrode, these results present a set of guidelines to help choose "alligator clips" for molecular electronic devices.

  10. Evolution of corticosteroid specificity for human, chicken, alligator and frog glucocorticoid receptors.

    PubMed

    Katsu, Yoshinao; Kohno, Satomi; Oka, Kaori; Baker, Michael E

    2016-09-01

    We investigated the evolution of the response of human, chicken, alligator and frog glucocorticoid receptors (GRs) to dexamethasone, cortisol, cortisone, corticosterone, 11-deoxycorticosterone, 11-deoxycortisol and aldosterone. We find significant differences among these vertebrates in the transcriptional activation of their full length GRs by these steroids, indicating that there were changes in the specificity of the GR for steroids during the evolution of terrestrial vertebrates. To begin to study the role of interactions between different domains on the GR in steroid sensitivity and specificity for terrestrial GRs, we investigated transcriptional activation of truncated GRs containing their hinge domain and ligand binding domain (LBD) fused to a GAL4 DNA binding domain (GAL4-DBD). Compared to corresponding full length GRs, transcriptional activation of GAL4-DBD_GR-hinge/LBD constructs required higher steroid concentrations and displayed altered steroid specificity, indicating that interactions between the hinge/LBD and other domains are important in glucocorticoid activation of these terrestrial GRs. PMID:27317937

  11. ALLIGATOR - An apparatus for ion beam assisted deposition with a broad-beam ion source

    NASA Astrophysics Data System (ADS)

    Wituschek, H.; Barth, M.; Ensinger, W.; Frech, G.; Rück, D. M.; Leible, K. D.; Wolf, G. K.

    1992-04-01

    Ion beam assisted deposition is a versatile technique for preparing thin films and coatings for various applications. Up to now a prototype setup for research purposes has been used in our laboratory. Processing of industrial standard workpieces requires a high current ion source with broad beam and high uniformity for homogeneous bombardment. In this contribution a new apparatus for large area samples will be described. It is named ALLIGATOR (German acronym of facility for ion assisted evaporation on transverse movable or rotary targets). In order to have a wide energy range available two ion sources are used. One delivers a beam energy up to 1.3 keV. The other is suitable for energies from 5 keV up to 40 keV. The ``high-energy'' ion source is a multicusp multiaperture source with 180-mA total current and a beam diameter of 280 mm at the target position.

  12. Nuclear β-catenin localization supports homology of feathers, avian scutate scales, and alligator scales in early development.

    PubMed

    Musser, Jacob M; Wagner, Günter P; Prum, Richard O

    2015-01-01

    Feathers are an evolutionary novelty found in all extant birds. Despite recent progress investigating feather development and a revolution in dinosaur paleontology, the relationship of feathers to other amniote skin appendages, particularly reptile scales, remains unclear. Disagreement arises primarily from the observation that feathers and avian scutate scales exhibit an anatomical placode-defined as an epidermal thickening-in early development, whereas alligator and other avian scales do not. To investigate the homology of feathers and archosaur scales we examined patterns of nuclear β-catenin localization during early development of feathers and different bird and alligator scales. In birds, nuclear β-catenin is first localized to the feather placode, and then exhibits a dynamic pattern of localization in both epidermis and dermis of the feather bud. We found that asymmetric avian scutate scales and alligator scales share similar patterns of nuclear β-catenin localization with feathers. This supports the hypothesis that feathers, scutate scales, and alligator scales are homologous during early developmental stages, and are derived from early developmental stages of an asymmetric scale present in the archosaur ancestor. Furthermore, given that the earliest stage of β-catenin localization in feathers and archosaur scales is also found in placodes of several mammalian skin appendages, including hair and mammary glands, we hypothesize that a common skin appendage placode originated in the common ancestor of all amniotes. We suggest a skin placode should not be defined by anatomical features, but as a local, organized molecular signaling center from which an epidermal appendage develops. PMID:25963196

  13. Cadmium and lead residues in field-collected red swamp crayfish (Procambarus clarkii) and uptake by alligator weed, Alternanthera philoxiroides

    SciTech Connect

    Naqvi, S.M.; Howell, R.D.; Sholas, M. . Dept. of Biological Sciences and Health Research Center)

    1993-01-01

    The whole-body residues of Cd and Pb in the tissues of Louisiana swamp crayfish (Procambarus clarkii) were determined by flame AAS technique. Test animals were collected from roadside ditches alongside major highways. The water and soil samples were also collected from the same sites. The mean Cd and Pb concentrations in crayfish tissues were 0.46 and 0.07, respectively. The levels of Cd and Pb in the water were 0.09 and 0.04; and in soil were 2.85 and 0.87 mg/1, respectively. The concentration of cadmium was 32 and Pb 12 times more than in the water. The bioaccumulation factors (BF) for Cd and Pb in crayfish tissues were 5.1 and 1.7, respectively. Alligator weed (Alternanthera philoxiroides) plants were exposed to 0.5 mg/1 Cd-chloride or Pb-nitrate solutions for 3 wk period, thrice. The mean Pb accumulation in roots was 1.31 mg/1, followed by stem (0.078 mg/1), but Cd only accumulated in root (0.83 mg/1). The BF for Pb and Cd in plant tissues were 14.8 and 16.6, respectively. The uptake of metals was time-dependent. These data suggest that although there is no biomagnification of Cd and Pb from alligator weed to crayfish, both metals readily accumulate in field-collected crayfish and laboratory-exposed alligator weed.

  14. Interaction of environmental chemicals with the estrogen and progesterone receptors from the oviduct of the American alligator.

    PubMed Central

    Vonier, P M; Crain, D A; McLachlan, J A; Guillette, L J; Arnold, S F

    1996-01-01

    Reports of reproductive abnormalities in the American alligator from Lake Apopka, Florida, have been linked to a spill of DDT and other pesticides suspected of having hormonelike activity. To determine whether environmental chemicals had the potential to function as exogenous hormones in the American alligator, we examined the ability of chemicals to bind the estrogen receptor (aER) and progesterone receptor (aPR) in a protein extract prepared from the oviduct of the alligator. In competition binding assays with [3H]17 beta-estradiol, some DDT metabolites showed inhibition of [3H]17 beta-estradiol binding to aER. A combination of DDTs demonstrated an additive decrease in [3H]17 beta-estradiol binding to aER. Modern-use chemicals such as alachlor, trans-nonachlor, endosulfan, and atrazine also competed with [3H]17 beta-estradiol for binding to the aER. To test the effect of chemicals identified in alligator eggs from Lake Apopka on [3H]17 beta-estradiol binding, we mixed these chemicals at concentrations measured in eggs in the competition binding assay. 2,2-bis(4-chlorophenyl)-N-(methoxymethyl)acetamide (p,p'-DDD) and trans-nonachlor, both found in Lake Apopka, interacted with aER, whereas others such as chlordane and toxaphene did not. Surprisingly, combinations of these chemicals decreased [3H]17 beta-estradiol binding in a greater than additive manner. To assess the ability of chemicals to interact with aPR, we performed commpetition binding assays with the synthetic progestin [3H]R5020. Most of the chemicals tested did not reduce [3H]R5020 binding to aPR, whereas endosulfan, alachlor, and kepone inhibited binding. These results provide the first evidence that environmental chemicals bind the aER and aPR from the American alligator, supporting the hypothesis that the reported reproductive abnormalities may be related to the modulation of endocrine-related responses. The findings that combinations of chemicals demonstrated a greater than additive interaction with

  15. The orientation and navigation of juvenile alligators: evidence of magnetic sensitivity

    USGS Publications Warehouse

    Rodda, Gordon H.

    1984-01-01

    Displaced juvenile alligators, Alligator mississipiensis, were released on land in a 9 m diameter dodecagonal arena to test their ability to orient in the absence of terrestrial landmarks. Navigational ability seemed to improve with age. When displaced along a fairly direct route yearlings (age 7–14 months) compensated for their displacement, moving in the direction from the arena to their home sites. When displaced by a circuitous route, yearlings failed to compensate for their displacement, exhibiting instead simple compass orientation in a direction that would have returned them to water had they been released on land near the site where they were captured. The older juveniles were oriented in a homeward direction under all displacement and test conditions. The latter animals may have been using geomagnetic map information to select their homeward directions as the errors in their homeward bearings correlated with small deviations in the geomagnetic field's dip angle at the time of the test (1980r s=−0.6047,P=0.0131, all testsr s= −0.4652,P=0.0084). This effect appeared to depend on a very short-term assessment of geomagnetic conditions, as values measured 20 min before or 30 min after the tests began did not correlate with the directions the animals moved. The older juveniles appeared to use magnetically quiet hours on the night of their capture as the baseline from which to measure the geomagnetic deviations that occurred at the time of the arena test. The magnitude of the magnetic effect in the older animals suggests that the geomagnetic information may have been used to perform a ‘map’ step, as small fluctuations in dip angle correlated with much larger deviations in homeward bearings. In addition, the compass-oriented yearlings and the seemingly route-based behavior of the homeward-oriented yearlings did not appear to be influenced by geomagnetic conditions. These findings have many parallels in results obtained from bird orientation studies

  16. Primary alkaline magmas associated with the Quaternary Alligator Lake volcanic complex, Yukon Territory, Canada

    NASA Astrophysics Data System (ADS)

    Eiché, G. E.; Francis, D. M.; Ludden, J. N.

    1987-02-01

    The Alligator Lake complex is a Quaternary alkaline volcanic center located in the southern Yukon Territory of Canada. It comprises two cinder cones which cap a shield consisting of five distinct lava units of basaltic composition. Units 2 and 3 of this shield are primitive olivine-phyric lavas (13.5 19.5 cation % Mg) which host abundant spinel lherzolite xenoliths, megacrysts, and granitoid fragments. Although the two lava types have erupted coevally from adjacent vents and are petrographically similar, they are chemically distinct. Unit 2 lavas have considerably higher abundances of LREE, LILE, and Fe, but lower HREE, Y, Ca, Si, and Al relative to unit 3 lavas. The 87Sr/86Sr and 143Nd/144Nd isotopic ratios of these two units are, however, indistinguishable. The differences between these two lava types cannot be explained in terms of low pressure olivine fractionation, and the low concentrations of Sr, Nb, P, and Ti in the granitoid xenoliths relative to the primitive lavas discounts differential crustal contamination. The abundance of spinel lherzolite xenoliths and the high Mg contents in the lavas of both units indicates that their compositional differences originated in the upper mantle. The Al and Si systematics of these lavas suggests that, compared to unit 3 magmas, the unit 2 magmas may have segregated at greater depths from a garnet lherzolite mantle. The identical isotopic composition and similar ratios of highly incompatible elements in these two lava units argues against their differences being a consequence of random metasomatism or mantle heterogeneity. The lower Y and HREE contents but higher concentrations of incompatible elements in the unit 2 lavas relative to unit 3 can be most simply explained by differential partial melting of similar garnet-bearing sources. The unit 2 magmas thus appear to have been generated by smaller degrees of melting at a greater depth than the unit 3 magmas. The contemporaneous eruption of two distinct but

  17. Microhabitat use, home range, and movements of the alligator snapping turtle, Macrochelys temminckii, in Oklahoma

    USGS Publications Warehouse

    Riedle, J.D.; Shipman, P.A.; Fox, S. F.; Leslie, David M., Jr.

    2006-01-01

    Little is known about the ecology of the alligator snapping turtle, Macrochelys temminckii, particularly dentography and behavior. To learn more about the species in Oklahoma, we conducted a telemetry project on 2 small streams at Sequoyah National Wildlife Refuge, an 8,417.5-ha refuge located in east-central Oklahoma. Between June 1999 and August 2000, we fitted 19 M. temminckii with ultrasonic telemetry tags and studied turtle movements and microhahitat use. Turtles were checked 2 to 3 times weekly in summer and sporadically in winter. Several microhabitat variables were measured at each turtle location and a random location to help quantify microhabitat use vs. availability. We recorded 147 turtle locations. Turtles were always associated with submerged cover with a high percentage of overhead canopy cover. Turtles used deeper depths in late summer (but not deeper depths than random locations) and deeper depths in mid-winter (and deeper depths than random locations) than in early summer. They used shallower depths than random locations in early summer. This seasonal shift in depth use might be thermoregulatory, although evidence for this is indirect. The mean linear home range for all turtles was 777.8 m. Females had larger home ranges than males, and juveniles had larger home ranges than adults, although the latter was not statistically significant. Macrochelys temminckii used submerged structures as a core site, and stayed at each core site for an average of 12.3 d.

  18. Formation and regression of the corpus luteum of the American alligator

    USGS Publications Warehouse

    Guillette, L.J.; Woodward, A.R.; You-Xiang, Q.; Cox, M.C.; Matter, J.H.; Gross, T.S.

    1995-01-01

    Luteal morphology of the American alligator is unique when compared to other reptiles but is similar to that of its phylogenetic relatives, the birds. The theca is extensively hypertrophied, but the granulosa never fills the cavity formed following the ovulation of the ovum. The formation of the corpus luteum (CL) is correlated with elevated plasma progesterone concentrations, which decline dramatically after oviposition with the onset of luteolysis. Unlike those of most other reptiles, the central luteal cell mass is composed of two cell types; one presumably is derived from the granulosa, whereas the other is from the theca interna. Both cell types are present throughout gravidity but only one cell type is seen during mid to late luteolysis. A significant decline in luteal volume occurs following oviposition and continues throughout the post-oviposition period. The fastest decline in luteal volume occurs in the month immediately after oviposition; this rate then slows. Luteolysis appears to continue for a year or more following oviposition, as distinct structures of luteal origin can still be identified in animals 9 months after oviposition. The size of persistent CL can be used to determine whether a given female oviposited during the previous nesting season. Females with CL having volumes greater than 0.2 cm2 or CL diameters greater than 0.4 cm were active the previous season. 

  19. Thermoluminescence and excess 226Ra decay dating of late Quaternary fluvial sands, East Alligator River, Australia

    NASA Astrophysics Data System (ADS)

    Murray, Andrew; Wohl, Ellen; East, Jon

    1992-01-01

    Thermoluminescence (TL) dating was applied to seven samples of siliceous fluvial sands from the East Alligator River of Northern Australia, giving ages ranging from modern to 6000 yr B.P. Two methods of estimating the equivalent dose (ED), total bleach and regenerative, were applied to the 90- to 125-μm quartz fraction of the samples in order to determine the reliability and internal consistency of the technique. High-resolution γ and α spectroscopy were used to measure radionuclide contents; these measurements revealed an excess 226Ra activity compared with 230Th. This excess decreased with depth, and was used directly to derive mean sedimentation rates, and thus sediment ages. Both this method and one 14C date confirmed the validity of the TL values, which increased systematically with depth and were consistent with site stratigraphy. TL was of limited use in the dating of these late Holocene deposits because of age uncertainties of 500 to 1600 yr, resulting from a significant residual ED. This residual probably resulted from incomplete bleaching during reworking upstream of the sampling site. For Pleistocene deposits, the residual ED will be less significant because of higher total EDs, and TL dates will be correspondingly more accurate.

  20. Two modes of motion of the alligator lizard cochlea: Measurements and model predictions

    NASA Astrophysics Data System (ADS)

    Aranyosi, A. J.; Freeman, Dennis M.

    2005-09-01

    Measurements of motion of an in vitro preparation of the alligator lizard basilar papilla in response to sound demonstrate elliptical trajectories. These trajectories are consistent with the presence of both a translational and rotational mode of motion. The translational mode is independent of frequency, and the rotational mode has a displacement peak near 5 kHz. These measurements can be explained by a simple mechanical system in which the basilar papilla is supported asymmetrically on the basilar membrane. In a quantitative model, the translational admittance is compliant while the rotational admittance is second order. Best-fit model parameters are consistent with estimates based on anatomy and predict that fluid flow across hair bundles is a primary source of viscous damping. The model predicts that the rotational mode contributes to the high-frequency slopes of auditory nerve fiber tuning curves, providing a physical explanation for a low-pass filter required in models of this cochlea. The combination of modes makes the sensitivity of hair bundles more uniform with radial position than that which would result from pure rotation. A mechanical analogy with the organ of Corti suggests that these two modes of motion may also be present in the mammalian cochlea.

  1. Invertebrate community composition differs between invasive herb alligator weed and native sedges

    NASA Astrophysics Data System (ADS)

    Bassett, Imogen E.; Paynter, Quentin; Beggs, Jacqueline R.

    2012-05-01

    Chemical and/or architectural differences between native and exotic plants may influence invertebrate community composition. According to the enemy release hypothesis, invasive weeds should host fewer and less specialised invertebrates than native vegetation. Invertebrate communities were compared on invasive Alternanthera philoxeroides (alligator weed) and native sedges (Isolepis prolifer and Schoenoplectus tabernaemontani) in a New Zealand lake. A. philoxeroides is more architecturally and chemically similar to I. prolifer than to S. tabernaemontani. Lower invertebrate abundance, richness and proportionally fewer specialists were predicted on A. philoxeroides compared to native sedges, but with greatest differences between A. philoxeroides and S. tabernaemontani. A. philoxeroides is more architecturally and chemically similar to I. prolifer than to S. tabernaemontani. Invertebrate abundance showed taxa-specific responses, rather than consistently lower abundance on A. philoxeroides. Nevertheless, as predicted, invertebrate fauna of A. philoxeroides was more similar to that of I. prolifer than to S. tabernaemontani. The prediction of a depauperate native fauna on A. philoxeroides received support from some but not all taxa. All vegetation types hosted generalist-dominated invertebrate communities with simple guild structures. The enemy release hypothesis thus had minimal ability to predict patterns in this system. Results suggest the extent of architectural and chemical differences between native and invasive vegetation may be useful in predicting the extent to which they will host different invertebrate communities. However, invertebrate ecology also affects whether invertebrate taxa respond positively or negatively to weed invasion. Thus, exotic vegetation may support distinct invertebrate communities despite similar overall invertebrate abundance to native vegetation.

  2. Structure and fracture resistance of alligator gar (Atractosteus spatula) armored fish scales.

    PubMed

    Yang, Wen; Gludovatz, Bernd; Zimmermann, Elizabeth A; Bale, Hrishikesh A; Ritchie, Robert O; Meyers, Marc A

    2013-04-01

    The alligator gar is a large fish with flexible armor consisting of ganoid scales. These scales contain a thin layer of ganoine (microhardness ~2.5 GPa) and a bony body (microhardness ~400 MPa), with jagged edges that provide effective protection against predators. We describe here the structure of both ganoine and bony foundation and characterize the mechanical properties and fracture mechanisms. The bony foundation is characterized by two components: a mineralized matrix and parallel arrays of tubules, most of which contain collagen fibers. The spacing of the empty tubules is ~60 μm; the spacing of those filled with collagen fibers is ~7 μm. Using micromechanical testing of such scales in a variable-pressure scanning electron microscope, we identify interactions between propagating cracks and the microstructure, and show that the toughness of the scales increases with crack extension in a classical resistance-curve response from the activation of extrinsic toughening mechanisms. We demonstrate how mechanical damage evolves in these structures, and further identify that the reinforcement of the mineral by the network of collagen fibers is the principal toughening mechanism resisting such damage. Additionally, we define the anisotropy of the toughness of the scales and relate this to the collagen fiber orientation. PMID:23274521

  3. Sorption of sulphamethoxazole by the biochars derived from rice straw and alligator flag.

    PubMed

    Li, Tingqiang; Han, Xuan; Liang, Chengfeng; Shohag, M J I; Yang, Xiaoe

    2015-01-01

    The sorption ability of sulphamethoxazole (SMX) by biochar derived from rice straw (RS) and alligator flag (AF) at 600°C was studied to assess the ability of biochar as adsorbent to remove SMX from aqueous solution. The results indicated that sorption of SMX by biochars was well described using the Langmuir equation (R2>0.94), and the maximum sorption parameter (Q) of RS (3650 mg kg(-1)) was much higher than that of AF (1963 mg kg(-1)). Temperature had no effect on SMX sorption by biochars, while thermodynamics analysis indicated that the sorption of SMX on both biochars was a spontaneous physical process. The d 250 RS (diameter of RS sieved through 250 µm) and d 150 AF (diameter of AF sieved through 150 µm) showed excellent sorption ability for SMX. The sorption amount of RS was larger than that of AF when pH<7, whereas, the sorption amount of AF surpassed RS when pH≥7. The presence of Cu2+ and/or Cd2+ ion at low concentrations (20 mg L(-1)) significantly (P<0.05) increased the sorption of SMX on both RS and AF. Our study confirms that biochar derived from the wetland plants could be used as effective adsorbents to remove SMX from aqueous solution. PMID:25413119

  4. Analysis of chorioallantoic membranes to assess PCB accumulation in American alligators and Loggerhead sea turtles from the coast of South Carolina

    SciTech Connect

    Cobb, G.P.; Wood, P.D.; O`Quinn, M.

    1995-12-31

    Investigation of contaminant burdens in threatened and endangered species is difficult due to the small number of samples that can be collected. Many samples can be collected if the sampling methods are non-lethal and more specifically non-invasive. Analysis of chorioallantoic membranes is demonstrated for American alligators and Loggerhead sea turtles. Significant differences were found in PCB, uptake by alligators from the Ashepoo-Combahee-Edisto Basin reference site and a contaminated site in Winyah Bay. Intrasite and intersite differences in uptake and distribution of PCB homologues were noted. These data will be discussed as they relate to egg viability and embryo development.

  5. Direct comparison of the electronic coupling efficiency of sulfur and selenium alligator clips for molecules adsorbed onto gold electrodes

    NASA Astrophysics Data System (ADS)

    Patrone, L.; Palacin, S.; Bourgoin, J. P.

    2003-05-01

    Scanning tunneling microscopy experiments have been performed to compare the electronic coupling provided by S and by Se used as alligator clips for bisthiol- and biselenol-terthiophene molecules adsorbed onto gold. The molecules were inserted in a dodecanethiol (DT) self-assembled monolayer. Their apparent height above the dodecanethiol matrix was used as a measure of the electronic coupling strength corresponding to S and Se, respectively. We show that the insertion behaviors of the two molecules are qualitatively the same, and that Se provides systematically a better coupling link than S, whatever the tunneling conditions.

  6. 75 FR 67784 - STP Nuclear Operating Company South Texas Project Electric Generating Station, Units 3 and 4...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-03

    ... femoralis septentrionalis) and the Federally threatened American alligator (Alligator mississippiensis). The... have no impacts on the Northern Aplomado falcon, the American alligator, or their habitats. The...

  7. A moss-covered alligator rests in the sun at KSC. copy form; photos beginning with 99PD are only ava

    NASA Technical Reports Server (NTRS)

    2000-01-01

    On top of what may be a nest on the edge of an algae-coated canal near Schwartz Rd. at Kennedy Space Center, a moss-covered alligator rests while keeping a wary eye open for trespassers. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the Merritt Island National Wildlife Refuge, which shares a boundary with the Center. American alligators feed and rest in the water, and usually lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, as well as a variety of insects.

  8. Mercury contamination in alligators (Melanosuchus niger) from Mamirauá Reservoir (Brazilian Amazon) and human health risk assessment.

    PubMed

    Correia, Jozélia; Cesar, Ricardo; Marsico, Eliane; Diniz, George Tadeu Nunes; Zorro, Mauricio Camargo; Castilhos, Zuleica

    2014-12-01

    Mercury (Hg) concentrations in muscles of wild alligators (Melanosuchus niger) from the Mamirauá Reservoir (a reference area in the Brazilian Amazon) and the human health risks associated with its consumption were assessed. The mean Hg concentration in alligator muscles was 0.407 ± 0.114 μg/g (N = 61). Close to 5 % of the muscle samples showed Hg levels above the World Health Organization guideline for fish consumption (0.5 μg/g). A positive and significant relationship was observed between Hg concentrations in muscle and the age of the specimens. The dose-response approach suggests that close to 27.4 years is required for half of the exposed specimens to attain 0.5 μg/g. The hazard quotient (HQ) is a risk indicator which defines the ratio of exposure level and a toxicological reference dose. HQ resulted above the unity for all the specimens when the ingestion rate for riverine communities (200 g of muscle per day) is considered, indicating the existence of hazard. When the ingestion rate for market consumers (28.57 g/day) is considered, the risks are much lower (mean HQ = 0.55), suggesting that such group is not at risk. The establishment of local and regional ingestion rates for riverine populations and market consumers is extremely recommended. PMID:25017870

  9. Molecular characterization of the Chinese alligator follicle-stimulating hormone β subunit (FSHβ) and its expression during the female reproductive cycle.

    PubMed

    Zhang, Rui; Zhang, Shengzhou; Zhu, Xue; Zhou, Yongkang; Wu, Xiaobing

    2015-05-01

    The Chinese alligator Alligator sinensis is an endangered species endemic to China, it has a highly specialized reproductive pattern with low fecundity. Up to date, little is known about the regulation of its female reproductive cycle. Follicle-stimulating hormone (FSH), a glycoprotein hormone, plays a key role in stimulating and regulating ovarian follicular development and egg production. In this study, the complete FSHβ cDNA from the ovary of the Chinese alligator was obtained for the first time, it consists of 843-bp nucleotides, including 120-bp nucleotides of the 5'-untranslated region (UTR), 396-bp of the open reading frame, and 3'-UTR of 327-bp nucleotides. It encodes a 131-amino acid precursor molecule of FSHβ with a signal peptide of 18 amino acids followed by a mature protein of 113 amino acids. Its deduced amino acid sequence shares high identities with the American alligator (100%) and birds (89-92%). Phylogenetic tree analysis of the FSHβ amino acid sequence indicated that alligators cluster into the bird branch. Tissue distribution analyses indicated that FSHβ mRNA is expressed in ovary, intestine and liver with the highest level in the ovary, while not in stomach, pancreas, heart, thymus and thyroid. Expression of FSHβ in ovary increases in May (breeding prophase) and peaks in July (breeding period), it is maintained at high levels through September, then decreases significantly in November (post-reproductive period) and remains relatively low from January to March (hibernating period). These temporal changes of FSHβ expression implicated that it might play an important role in promoting ovarian development during the female reproductive cycle. PMID:25626184

  10. A Comprehensive Analysis of the Phylogeny, Genomic Organization and Expression of Immunoglobulin Light Chain Genes in Alligator sinensis, an Endangered Reptile Species

    PubMed Central

    Lu, Yan; Zhang, Chenglin; Wu, Xiaobing; Han, Haitang; Zhao, Yaofeng; Ren, Liming

    2016-01-01

    Crocodilians are evolutionarily distinct reptiles that are distantly related to lizards and are thought to be the closest relatives of birds. Compared with birds and mammals, few studies have investigated the Ig light chain of crocodilians. Here, employing an Alligator sinensis genomic bacterial artificial chromosome (BAC) library and available genome data, we characterized the genomic organization of the Alligator sinensis IgL gene loci. The Alligator sinensis has two IgL isotypes, λ and κ, the same as Anolis carolinensis. The Igλ locus contains 6 Cλ genes, each preceded by a Jλ gene, and 86 potentially functional Vλ genes upstream of (Jλ-Cλ)n. The Igκ locus contains a single Cκ gene, 6 Jκs and 62 functional Vκs. All VL genes are classified into a total of 31 families: 19 Vλ families and 12 Vκ families. Based on an analysis of the chromosomal location of the light chain genes among mammals, birds, lizards and frogs, the data further confirm that there are two IgL isotypes in the Alligator sinensis: Igλ and Igκ. By analyzing the cloned Igλ/κ cDNA, we identified a biased usage pattern of V families in the expressed Vλ and Vκ. An analysis of the junctions of the recombined VJ revealed the presence of N and P nucleotides in both expressed λ and κ sequences. Phylogenetic analysis of the V genes revealed V families shared by mammals, birds, reptiles and Xenopus, suggesting that these conserved V families are orthologous and have been retained during the evolution of IgL. Our data suggest that the Alligator sinensis IgL gene repertoire is highly diverse and complex and provide insight into immunoglobulin gene evolution in vertebrates. PMID:26901135

  11. A Comprehensive Analysis of the Phylogeny, Genomic Organization and Expression of Immunoglobulin Light Chain Genes in Alligator sinensis, an Endangered Reptile Species.

    PubMed

    Wang, Xifeng; Cheng, Gang; Lu, Yan; Zhang, Chenglin; Wu, Xiaobing; Han, Haitang; Zhao, Yaofeng; Ren, Liming

    2016-01-01

    Crocodilians are evolutionarily distinct reptiles that are distantly related to lizards and are thought to be the closest relatives of birds. Compared with birds and mammals, few studies have investigated the Ig light chain of crocodilians. Here, employing an Alligator sinensis genomic bacterial artificial chromosome (BAC) library and available genome data, we characterized the genomic organization of the Alligator sinensis IgL gene loci. The Alligator sinensis has two IgL isotypes, λ and κ, the same as Anolis carolinensis. The Igλ locus contains 6 Cλ genes, each preceded by a Jλ gene, and 86 potentially functional Vλ genes upstream of (Jλ-Cλ)n. The Igκ locus contains a single Cκ gene, 6 Jκs and 62 functional Vκs. All VL genes are classified into a total of 31 families: 19 Vλ families and 12 Vκ families. Based on an analysis of the chromosomal location of the light chain genes among mammals, birds, lizards and frogs, the data further confirm that there are two IgL isotypes in the Alligator sinensis: Igλ and Igκ. By analyzing the cloned Igλ/κ cDNA, we identified a biased usage pattern of V families in the expressed Vλ and Vκ. An analysis of the junctions of the recombined VJ revealed the presence of N and P nucleotides in both expressed λ and κ sequences. Phylogenetic analysis of the V genes revealed V families shared by mammals, birds, reptiles and Xenopus, suggesting that these conserved V families are orthologous and have been retained during the evolution of IgL. Our data suggest that the Alligator sinensis IgL gene repertoire is highly diverse and complex and provide insight into immunoglobulin gene evolution in vertebrates. PMID:26901135

  12. Alligator ridge district, East-Central Nevada: Carlin-type gold mineralization at shallow depths

    USGS Publications Warehouse

    Nutt, C.J.; Hofstra, A.H.

    2003-01-01

    Carlin-type deposits in the Alligator Ridge mining district are present sporadically for 40 km along the north-striking Mooney Basin fault system but are restricted to a 250-m interval of Devonian to Mississippian strata. Their age is bracketed between silicified ca. 45 Ma sedimentary rocks and unaltered 36.5 to 34 Ma volcanic rocks. The silicification is linked to the deposits by its continuity with ore-grade silicification in Devonian-Mississippian strata and by its similar ??18O values (_e1???17???) and trace element signature (As, Sb, Tl, Hg). Eocene reconstruction indicates that the deposits formed at depths of ???300 to 800 m. In comparison to most Carlin-type gold deposits, they have lower Au/Ag, Au grades, and contained Au, more abundant jasperoid, and textural evidence from deposition of an amorphous silica precursor in jasperoid. These differences most likely result from their shallow depth of formation. The peak fluid temperature (_e1???230??C) and large ??18OH2O value shift from the meteroric water line (_e1???20???) suggest that ore fluids were derived from depths of 8 km or more. A magnetotelluric survey indicates that the Mooney Basin fault system penetrates to mid-crustal depths. Deep circulation of meteoric water along the Mooney Basin fault system may have been in response to initial uplift of the East Humboldt-Ruby Mountains metamorphic core complex; convection also may have been promoted by increased heat flow associated with large magnitude extension in the core complex and regional magmatism. Ore fluids ascended along the fault system until they encountered impermeable Devonian and Mississippian shales, at which point they moved laterally through permeable strata in the Devonian Guilmette Formation, Devonian-Mississippian Pilot Shale, Mississippian Joana Limestone, and Mississippian Chainman Shale toward erosional windows where they ascended into Eocene fluvial conglomerates and lake sediments. Most gold precipitated by sulfidation of host

  13. SEX-STEROID AND THYROID HORMONE CONCENTRATIONS IN JUVENILE ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED AND REFERENCE LAKES IN FLORIDA. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. Effect of aqueous extracts of alligator pear seed (Persea americana mill) on blood glucose and histopathology of pancreas in alloxan-induced diabetic rats.

    PubMed

    Edem, Do; Ekanem, Is; Ebong, Pe

    2009-07-01

    Effects of aqueous extract of alligator pear seed on normal and alloxan-induced diabetic rats were investigated in 6 groups of rats (5 rats per group). Test groups were made diabetic with intra-peritoneal injection of alloxan and treated with 300 mg and 600 mg/kg body weight of alligator pear seed extract. Two non-diabetic groups were also administered with 300 mg and 600 mg/kg body weight extract. The levels of blood glucose were examined in all 6 experimental groups. In diabetic rats, blood glucose levels were significantly reduced (p<0.05) by 73.26-78.24% on consumption of the extracts, with greater effect exhibited by the 600 mg/kg extract. In normal rats, blood glucose levels were significantly reduced (p<0.05) by 34.68-38.9% on consumption of the seed extract. Histological studies showed a degenerative effect on the pancreatic islet cells of diabetic rats. The result suggested restorative (protective) effect of the extract on pancreatic islet cells. Administration of aqueous extract of alligator pear seed may contribute significantly to the reduction of blood glucose levels and can be useful in the treatment of diabetes. PMID:19553173

  15. Summary of well construction, testing, and preliminary findings from the Alligator Alley test well, Broward County, Florida

    USGS Publications Warehouse

    Meyer, F.W.

    1988-01-01

    A 2,811-foot deep test well was drilled during 1980 in The Everglades along Alligator Alley as part of the Floridan Regional Aquifer Systems Analysis project. The well was cased 895 feet deep. Hydraulic packers were used to isolate selected zones in the open hole for water samples and measurement of water levels. The well penetrated the surficial and intermediate aquifers into the Floridan aquifer system. The top of the Floridan aquifer system occurs at 770 feet and includes limestone ranging in age from Oligocene to early Eocene. About 67 percent of the total thickness of the Floridan aquifer system was penetrated by the well. The chief water-producing zones in the Floridan aquifer system occur at about 1,030 feet and at about 2,560 feet. The 1,030-foot zone contains brackish artesian groundwater, and the 2,560-foot zone contains salty artesian groundwater similar in composition to seawater. The static water geothermal gradient is indicated, and radiocarbon activities suggest that the saltwater in the lower zone is younger than brackish groundwater in the upper zone. (USGS)

  16. A thermal history of the Proterozoic East Alligator River Terrain, N.T., Australia: a fission track study

    NASA Astrophysics Data System (ADS)

    Koul, Sohan L.; Wilde, A. R.; Tickoo, Awtar K.

    1988-01-01

    Radiometric data indicate a major thermal event in Proterozoic rocks of the East Alligator River Terrain, at 1870 Ma. These data, together with metamorphic mineral assemblages, demonstrate peak temperatures in excess of 600 ° C, close to the melting temperature of more deeply buried rocks. A cooling rate following peak metamorphism of 3°C/Ma is suggested. Fission-track dates of peak metamorphic phases, however, reveal a thermal event (or events), after 1650 Ma, rather than the peak metamorphic event. This rise in temperature was the result of thermal blanketing of the metamorphic basement by Carpentarian sediments and anomalous radiogenic heat flow from underlying granitoid gneiss. The temperatures so generated (≥ 175 ° C) were insufficient to reset Rb-Sr and K-Ar systems, but are clearly in excess of F.T. annealing temperatures for all the phases investigated. A cooling history, extending over 1000 m.y. and reflecting gradual erosion of the sedimentary cover, is revealed. This history is consistent with the extraordinary tectonic stability of the region. The importance of F.T. studies in establishing a thermal history is underscored, particularly when maximum temperatures experienced were less than those required to reset Rb-Sr and K-Ar systems.

  17. Conservation genetics of the alligator snapping turtle: cytonuclear evidence of range-wide bottleneck effects and unusually pronounced geographic structure

    USGS Publications Warehouse

    Echelle, A.A.; Hackler, J.C.; Lack, Justin B.; Ballard, S. R.; Roman, J.; Fox, S. F.; Leslie,, David M., Jr.; Van Den Bussche, Ronald A.

    2010-01-01

    A previous mtDNA study indicated that female-mediated gene flow was extremely rare among alligator snapping turtle populations in different drainages of the Gulf of Mexico. In this study, we used variation at seven microsatellite DNA loci to assess the possibility of male-mediated gene flow, we augmented the mtDNA survey with additional sampling of the large Mississippi River System, and we evaluated the hypothesis that the consistently low within-population mtDNA diversity reflects past population bottlenecks. The results show that dispersal between drainages of the Gulf of Mexico is rare (F STmsat  = 0.43, ΦSTmtDNA = 0.98). Past range-wide bottlenecks are indicated by several genetic signals, including low diversity for microsatellites (1.1–3.9 alleles/locus; H e = 0.06–0.53) and mtDNA (h = 0.00 for most drainages; π = 0.000–0.001). Microsatellite data reinforce the conclusion from mtDNA that the Suwannee River population might eventually be recognized as a distinct taxonomic unit. It was the only population showing fixation or near fixation for otherwise rare microsatellite alleles. Six evolutionarily significant units are recommended on the basis of reciprocal mtDNA monophyly and high levels of microsatellite DNA divergence.

  18. Estrogen receptor 1 (ESR1; ERα), not ESR2 (ERβ), modulates estrogen-induced sex reversal in the American alligator, a species with temperature-dependent sex determination.

    PubMed

    Kohno, Satomi; Bernhard, Melissa C; Katsu, Yoshinao; Zhu, Jianguo; Bryan, Teresa A; Doheny, Brenna M; Iguchi, Taisen; Guillette, Louis J

    2015-05-01

    All crocodilians and many turtles exhibit temperature-dependent sex determination where the temperature of the incubated egg, during a thermo-sensitive period (TSP), determines the sex of the offspring. Estrogens play a critical role in sex determination in crocodilians and turtles, as it likely does in most nonmammalian vertebrates. Indeed, administration of estrogens during the TSP induces male to female sex reversal at a male-producing temperature (MPT). However, it is not clear how estrogens override the influence of temperature during sex determination in these species. Most vertebrates have 2 forms of nuclear estrogen receptor (ESR): ESR1 (ERα) and ESR2 (ERβ). However, there is no direct evidence concerning which ESR is involved in sex determination, because a specific agonist or antagonist for each ESR has not been tested in nonmammalian species. We identified specific pharmaceutical agonists for each ESR using an in vitro transactivation assay employing American alligator ESR1 and ESR2; these were 4,4',4''-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol (PPT) and 7-bromo-2-(4-hydroxyphenyl)-1,3-benzoxazol-5-ol (WAY 200070), respectively. Alligator eggs were exposed to PPT or WAY 200070 at a MPT just before the TSP, and their sex was examined at the last stage of embryonic development. Estradiol-17β and PPT, but not WAY 200070, induced sex reversal at a MPT. PPT-exposed embryos exposed to the highest dose (5.0 μg/g egg weight) exhibited enlargement and advanced differentiation of the Müllerian duct. These results indicate that ESR1 is likely the principal ESR involved in sex reversal as well as embryonic Müllerian duct survival and growth in American alligators. PMID:25714813

  19. PLASMA DIHYDROTESTOSTERONE CONCENTRATIONS AND PHALLUS SIZE IN JUVENILE AMERICAN ALLIGATORS (A. MISSISSIPPIENSIS) FROM CONTAMINATED AND REFERENCE POPULATIONS.

    EPA Science Inventory

    Evidence increasingly suggests that some environmental pollutants are able to permanently affect development of the endocrine system in wildlife. Embryonic and neonatal exposure to these "endocrine-disrupting contaminants" can cause structural and functional abnormalities of the ...

  20. Isolation and characterization of microsatellite loci for alligator gar (Atractosteus spatula) and their variability in two other species (Lepisosteus oculatus and L. osseus) of Lepisosteidae

    USGS Publications Warehouse

    Moyer, G.R.; Sloss, Brian L.; Kreiser, B.R.; Feldheim, K.A.

    2009-01-01

    We report on the isolation of 17 polymorphic microsatellite loci from alligator gar (Atractosteus spatula), a large-bodied species that has experienced population declines across much of its range. These loci possessed 2-19 alleles and observed heterozygosities of 0-0.974. All loci conformed to Hardy-Weinberg equilibrium expectations, and none exhibited linkage disequilibrium. Nine and eight of these loci were found to be polymorphic in the related species Lepisosteus oculatus and L. osseus, respectively. These microsatellite loci should prove useful in conservation efforts of A. spatula through the study of population structure and hatchery broodstock management. ?? 2009 Blackwell Publishing Ltd.

  1. Water in the Lithospheric Mantle Beneath a Phanerozoic Continental Belt: FTIR Analyses of Alligator Lake Xenoliths (Yukon, Canada)

    NASA Technical Reports Server (NTRS)

    Gelber, McKensie; Peslier, Ann H.; Brandon, Alan D.

    2015-01-01

    Water in the mantle influences melting, metasomatism, viscosity and electrical conductivity. The Alligator Lake mantle xenolith suite is one of three bimodal peridotite suites from the northern Canadian Cordillera brought to the surface by alkali basalts, i.e., it consists of chemically distinct lherzolites and harzburgites. The lherzolites have equilibration temperatures about 50 C lower than the harzburgites and are thought to represent the fertile upper mantle of the region. The harzburgites might have come from slightly deeper in the mantle and/or be the result of a melting event above an asthenospheric upwelling detected as a seismic anomaly at 400-500 km depth. Major and trace element data are best interpreted as the lherzolite mantle having simultaneously experienced 20-25% partial melting and a metasomatic event to create the harzburgites. Well-characterized xenoliths are being analyzed for water by FTIR. Harzburgites contain 29-52 ppm H2O in orthopyroxene (opx) and (is) approximately140 ppm H2O in clinopyroxene (cpx). The lherzolites have H2O contents of 27-150 ppm in opx and 46-361 ppm in cpx. Despite correlating with enrichments in LREE, the water contents of the harzburgite pyroxenes are low relative to those of typical peridotite xenoliths, suggesting that the metasomatic agents were water-poor, contrarily to what has been suggested before. The water content of cpx is about double that of opx indicating equilibrium. Olivine water contents are low ((is) less than 5 ppm H2O) and out of equilibrium with those of opx and cpx, which may be due to H loss during xenolith ascent. This is consistent with olivines containing more water in their cores than their rims. Olivines exclusively exhibit water bands in the 3400-3000 cm-1 range, which may be indicative of a reduced environment.

  2. Taxonomic assessment of Alligator Snapping Turtles (Chelydridae: Macrochelys), with the description of two new species from the southeastern United States.

    PubMed

    Thomas, Travis M; Granatosky, Michael C; Bourque, Jason R; Krysko, Kenneth L; Moler, Paul E; Gamble, Tony; Suarez, Eric; Leone, Erin; Roman, Joe

    2014-01-01

    The Alligator Snapping Turtle, Macrochelys temminckii, is a large, aquatic turtle limited to river systems that drain into the Gulf of Mexico. Previous molecular analyses using both mitochondrial and nuclear DNA suggested that Macrochelys exhibits significant genetic variation across its range that includes three distinct genetic assemblages (western, central, and eastern = Suwannee). However, no taxonomic revision or morphological analyses have been conducted previously. In this study, we test previous hypotheses of distinct geographic assemblages by examining morphology, reanalyzing phylogeographic genetic structure, and estimating divergence dating among lineages in a coalescent framework using Bayesian inference. We reviewed the fossil record and discuss phylogeographic and taxonomic implications of the existence of three distinct evolutionary lineages. We measured cranial (n=145) and post-cranial (n=104) material on field-captured individuals and museum specimens. We analyzed 420 base pairs (bp) of mitochondrial DNA sequence data for 158 Macrochelys. We examined fossil Macrochelys from ca. 15-16 million years ago (Ma) to the present to better assess historical distributions and evaluate named fossil taxa. The morphological and molecular data both indicate significant geographical variation and suggest three species-level breaks among genetic lineages that correspond to previously hypothesized genetic assemblages. The holotype of Macrochelys temminckii is from the western lineage. Therefore, we describe two new species as Macrochelys apalachicolae sp. nov. from the central lineage and Macrochelys suwanniensis sp. nov. from the eastern lineage (Suwannee River drainage). Our estimates of divergence times suggest that the most recent common ancestor (MRCA) of M. temminckii (western) and M. apalachicolae (central) existed 3.2-8.9 Ma during the late Miocene to late Pliocene, whereas M. temminckii-M. apalachicolae and M. suwanniensis last shared a MRCA 5.5-13.4 Ma

  3. Geologic map of the Alligator Ridge area, including the Buck Mountain East and Mooney Basin Summit quadrangles and parts of the Sunshine Well NE and Long Valley Slough quadrangles, White Pine County, Nevada

    USGS Publications Warehouse

    Nutt, Constance J.

    2000-01-01

    Data set describes the geology of Paleozoic through Quaternary units in the Alligator Ridge area, which hosts disseminated gold deposits. These digital files were used to create the 1:24,000-scale geologic map of the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, east-central Nevada.

  4. EFFECT OF ACUTE STRESS ON PLASMA B-CORTICOSTERONE, ESTRADIOL-17B AND TESTOSTERONE CONCENTRATIONS IN JUVENILE AMERICAN ALLIGATORS COLLECTED FROM THREE SITES WITHIN THE KISSIMMEE-EVERGLADES DRAINAGE BASIN IN FLORIDA (USA)

    EPA Science Inventory

    The effect of acute stress on plasma b-corticosterone (B), testosterone (T) and estradiol-17b (E2), concentrations in juvenile alligators collected from sites with varying sediment contaminants was examined in this study. Dramatic increases in plasma B concentrations were observe...

  5. Water in the lithospheric mantle beneath a Phanerozoic continental belt: FTIR analyses of Alligator Lake Xenoliths (Yukon, Canada)

    NASA Astrophysics Data System (ADS)

    Gelber, M.; Peslier, A. H.; Brandon, A. D.

    2015-12-01

    Water in the mantle influences melting, metasomatism, viscosity and electrical conductivity. The Alligator Lake mantle xenolith suite is one of three bimodal peridotite suites from the northern Canadian Cordillera brought to the surface by alkali basalts, i.e., it consists of chemically distinct lherzolites and harzburgites [1-2]. The lherzolites have equilibration temperatures about 50 °C lower than the harzburgites and are thought to represent the fertile upper mantle of the region. The harzburgites might have come from slightly deeper in the mantle and/or be the result of a melting event above an asthenospheric upwelling detected as a seismic anomaly at 400-500 km depth [3]. Major and trace element data are best interpreted as the lherzolite mantle having simultaneously experienced 20-25% partial melting and a metasomatic event to create the harzburgites [3]. Well-characterized xenoliths are being analyzed for water by FTIR. Harzburgites contain 29-52 ppm H2O in orthopyroxene (opx) and ~140 ppm H2O in clinopyroxene (cpx). The lherzolites have H2O contents of 27-150 ppm in opx and 46-361 ppm in cpx. Despite correlating with enrichments in LREE, the water contents of the harzburgite pyroxenes are low relative to those of typical peridotite xenoliths [4], suggesting that the metasomatic agents were water-poor, contrarily to what has been suggested before [3]. The water content of cpx is about double that of opx indicating equilibrium. Olivine water contents are low (< 5 ppm H2O) and out of equilibrium with those of opx and cpx, which may be due to H loss during xenolith ascent. This is consistent with olivines containing more water in their cores than their rims. Olivines exclusively exhibit water bands in the 3400-3000 cm-1 range, which may be indicative of a reduced environment [5]. [1] Francis. 1987 JP 28, 569-97. [2] Eiche et al. 1987 CMP 95, 191-201. [3] Shi et al. 1997 CMP 131, 39-53. [4] Peslier et al. 2015 GGG 154, 98-117. [5] Bai et al. 1993 PCM 19, 460-71.

  6. 76 FR 71379 - Florida Power & Light Company, Turkey Point, Units 3 and 4; Draft Environmental Assessment and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-17

    ........... Florida panther..... E Trichechus manatus West Indian manatee. E Reptiles Alligator mississippiensis.. American alligator.. T/SA Caretta caretta loggerhead sea T turtle. Chelonia mydas green sea turtle.......

  7. 77 FR 20059 - License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ... draft EA and FONSI for the proposed action on November 17, 2011 (76 FR 71379), and established December... manatus West Indian manatee.... E Reptiles Alligator mississippiensis..... American alligator........

  8. Intense and specialized dendritic localization of the fragile X mental retardation protein in binaural brainstem neurons: a comparative study in the alligator, chicken, gerbil, and human.

    PubMed

    Wang, Yuan; Sakano, Hitomi; Beebe, Karisa; Brown, Maile R; de Laat, Rian; Bothwell, Mark; Kulesza, Randy J; Rubel, Edwin W

    2014-06-15

    Neuronal dendrites are structurally and functionally dynamic in response to changes in afferent activity. The fragile X mental retardation protein (FMRP) is an mRNA binding protein that regulates activity-dependent protein synthesis and morphological dynamics of dendrites. Loss and abnormal expression of FMRP occur in fragile X syndrome (FXS) and some forms of autism spectrum disorders. To provide further understanding of how FMRP signaling regulates dendritic dynamics, we examined dendritic expression and localization of FMRP in the reptilian and avian nucleus laminaris (NL) and its mammalian analogue, the medial superior olive (MSO), in rodents and humans. NL/MSO neurons are specialized for temporal processing of low-frequency sounds for binaural hearing, which is impaired in FXS. Protein BLAST analyses first demonstrate that the FMRP amino acid sequences in the alligator and chicken are highly similar to human FMRP with identical mRNA-binding and phosphorylation sites, suggesting that FMRP functions similarly across vertebrates. Immunocytochemistry further reveals that NL/MSO neurons have very high levels of dendritic FMRP in low-frequency hearing vertebrates including alligator, chicken, gerbil, and human. Remarkably, dendritic FMRP in NL/MSO neurons often accumulates at branch points and enlarged distal tips, loci known to be critical for branch-specific dendritic arbor dynamics. These observations support an important role for FMRP in regulating dendritic properties of binaural neurons that are essential for low-frequency sound localization and auditory scene segregation, and support the relevance of studying this regulation in nonhuman vertebrates that use low frequencies in order to further understand human auditory processing disorders. PMID:24318628

  9. Wrestling the process alligator

    SciTech Connect

    Springer, F.E.

    1993-04-01

    The Office of Hydropower Licensing's (FERC) current efforts to address the procedural problems in hydropower licensing are briefly described. A reorganization has taken place along functional lines to focus efforts in the three major programmatic functions: licensing, compliance, and dam safety. Other measures are also described.

  10. Tissue PAH, blood cell and tissue changes following exposure to water accommodated fractions of crude oil in alligator gar, Atractosteus spatula.

    PubMed

    Omar-Ali, Ahmad; Hohn, Claudia; Allen, Peter J; Rodriguez, Jose; Petrie-Hanson, Lora

    2015-07-01

    Alligator gar Atractosteus spatula acclimated to brackish water (9 ppt) were exposed to water accommodated fraction oil loadings (surrogate to Macondo Deepwater Horizon, northern Gulf of Mexico) of 0.5 and 4.0 gm oil/L tank water for 48 h. The surrogate oil was approximately 98% alkanes and alkynes and 2% petroleum aromatic hydrocarbons. The 2% petroleum aromatic hydrocarbons were predominately naphthalene. After 48 h, naphthalene levels in fish liver exposed to 0.5 or 4 gm oil/L were 547.79 and 910.68 ppb, while muscle levels were 214.11 and 253.84 ppb. There was a significant decrease in peripheral blood lymphocyte numbers and a significant reduction of granulocytes in the kidney marrow of the same fish. Tissue changes included hepatocellular vacuolization and necrosis, necrotizing pancreatitis, renal eosinophilia, and splenic congestion. After 7 days recovery, liver naphthalene levels decreased to 43.59 and 43.20 ppb, while muscle levels decreased to 9.74, and 16.78 ppb for oil exposures of 0, 0.5 or 4 g/L. In peripheral blood and kidney marrow, blood cell counts returned to normal. The severity of liver and kidney lesions lessened after 7 days recovery in non-oiled water, but splenic congestion remained in all gar. PMID:25956543

  11. Swamps, Alligators, and Adult Educators.

    ERIC Educational Resources Information Center

    Burnham, Byron R.

    1990-01-01

    Choice taking is a personal matter that results from consideration of the issues and beliefs about the nature of reality, humans, and social context. Systematic consideration of these elements forms the foundation of professional practice. (Author)

  12. Devin, Alligators, Jellyfish, and Me.

    ERIC Educational Resources Information Center

    Tsuchiyama, Elaine

    1997-01-01

    Describes how a first-grade teacher used the "hypothesis-test" approach with Devin, a first grader who struggled as a reader and writer. Points out that, when she started working with Devin, she wanted to understand his difficulties, but by the end, she realized that it was her curriculum, not his difficulties, that needed to be in the foreground.…

  13. Alligator clips to molecular dimensions

    NASA Astrophysics Data System (ADS)

    Prokopuk, Nicholas; Son, Kyung-Ah

    2008-09-01

    Techniques for fabricating nanospaced electrodes suitable for studying electron tunneling through metal-molecule-metal junctions are described. In one approach, top contacts are deposited/placed on a self-assembled monolayer or Langmuir-Blodgett film resting on a conducting substrate, the bottom contact. The molecular component serves as a permanent spacer that controls and limits the electrode separations. The top contact can be a thermally deposited metal film, liquid mercury drop, scanning probe tip, metallic wire or particle. Introduction of the top contact can greatly affect the electrical conductance of the intervening molecular film by chemical reaction, exerting pressure, or simply migrating through the organic layer. Alternatively, vacant nanogaps can be fabricated and the molecular component subsequently inserted. Strategies for constructing vacant nanogaps include mechanical break junction, electromigration, shadow mask lithography, focused ion beam deposition, chemical and electrochemical plating techniques, electron-beam lithography, and molecular and atomic rulers. The size of the nanogaps must be small enough to allow the molecule to connect both leads and large enough to keep the molecules in a relaxed and undistorted state. A significant advantage of using vacant nanogaps in the construction of metal-molecule-metal devices is that the junction can be characterized with and without the molecule in place. Any electrical artifacts introduced by the electrode fabrication process are more easily deconvoluted from the intrinsic properties of the molecule.

  14. Sound localization in the alligator.

    PubMed

    Bierman, Hilary S; Carr, Catherine E

    2015-11-01

    In early tetrapods, it is assumed that the tympana were acoustically coupled through the pharynx and therefore inherently directional, acting as pressure difference receivers. The later closure of the middle ear cavity in turtles, archosaurs, and mammals is a derived condition, and would have changed the ear by decoupling the tympana. Isolation of the middle ears would then have led to selection for structural and neural strategies to compute sound source localization in both archosaurs and mammalian ancestors. In the archosaurs (birds and crocodilians) the presence of air spaces in the skull provided connections between the ears that have been exploited to improve directional hearing, while neural circuits mediating sound localization are well developed. In this review, we will focus primarily on directional hearing in crocodilians, where vocalization and sound localization are thought to be ecologically important, and indicate important issues still awaiting resolution. PMID:26048335

  15. Sequencing three crocodilian genomes to illuminate the evolution of archosaurs and amniotes

    PubMed Central

    2012-01-01

    The International Crocodilian Genomes Working Group (ICGWG) will sequence and assemble the American alligator (Alligator mississippiensis), saltwater crocodile (Crocodylus porosus) and Indian gharial (Gavialis gangeticus) genomes. The status of these projects and our planned analyses are described. PMID:22293439

  16. Cloning and sequence analysis of the coding sequence of β-actin cDNA from the Chinese alligator and suitable internal reference primers from the β-actin gene.

    PubMed

    Zhu, H N; Zhang, S Z; Zhou, Y K; Wang, C L; Wu, X B

    2015-01-01

    β-Actin is an essential component of the cytoskeleton and is stably expressed in various tissues of animals, thus, it is commonly used as an internal reference for gene expression studies. In this study, a 1731-bp fragment of β-actin cDNA from Alligator sinensis was obtained using the homology cloning technique. Sequence analysis showed that this fragment contained the complete coding sequence of the β-actin gene (1128 bp), encoding 375 amino acids. The amino acid sequence of β-actin is highly conserved and its nucleotide sequence is slightly variable. Multiple alignment analyses showed that the nucleotide sequence of the β-actin gene from A. sinensis is very similar to sequences from birds, with 94-95% identity. Ten pairs of primers with different product sizes and different annealing temperatures were screened by PCR amplification, agarose gel electrophoresis, and DNA sequencing, and could be used as internal reference primers in gene expression studies. This study expands our knowledge of β-actin gene phylogenetic evolution and provides a basis for quantitative gene expression studies in A. sinensis. PMID:26505364

  17. Alligators, hospital birth and other urban legends.

    PubMed

    Cohain, Judy Slome

    2012-05-01

    The belief that hospital birth for low risk pregnancies has better outcomes than planned, attended homebirth is an urban legend. The choice of low-risk women to deliver in hospital is a result of the dominant and irrational human propensities to gossip, to follow the crowd and to cling to irrational hope. Rational analysis shows that planned homebirth with experienced trained attendants has the best outcomes for both mother and newborn for low risk pregnancy. PMID:22550002

  18. 77 FR 60135 - St. Johns National Wildlife Refuge, FL; Final Comprehensive Conservation Plan and Finding of No...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-02

    ... notice in the Federal Register on December 14, 2009 (74 FR 66147). For more about the process, see that... period via a Federal Register notice on July 7, 2011 (76 FR 39890). We provided more than 60 copies of... crested caracara (Caracara cheriway), and the American alligator (Alligator mississippiensis). As a...

  19. When You're Up to Your Ears in Alligators.

    ERIC Educational Resources Information Center

    Baumbach, Donna

    1997-01-01

    Discusses 10 challenges media specialists must overcome to effectively use technology in education. Highlights include people opposed to technology; teacher training to help develop collaborative relationships; establishing and using a comprehensive technology plan; assuming more professional responsibility; and empowerment. (LRW)

  20. A modular solar system provides hot water for alligator farm

    SciTech Connect

    Healey, H.M. )

    1994-03-01

    This article describes an 8,000 ft[sup 2] (743 m[sup 2]), site-built, large volume, Integral Collector Storage (ICS) solar water heating system installed at the farm to preheat water for the building washdown as part of a Florida Energy Office demonstration project. The project utilized at Foster Farms was a Shallow Solar Pond (SSP)--a modular, site-built, solar water heating system capable of providing in excess of 5,000 heated gallons (19 m[sup 3]) per day. During the past 10 years, a large number of solar systems have been proposed to provide economical hot water for industrial processes. Most of these water heating systems have proven to be too costly or too complex to compete with the traditional water heating methods using conventional fuels. Technology initiated at Lawrence Livermore Laboratory and expanded upon by the Tennessee Valley Authority was shown to have outstanding potential in Florida. This technology, which was utilized at Foster Farms, consists of a site-built large-volume ICAS system called the Shallow Solar Pond. Shallow Solar Pond (SSP) systems utilize the modular approach in which modules, built in a standardized size, are tied together to supply the required load. The SSP module can be ground mounted or installed on a roof. Each SSP module is typically 16 ft (5 m) wide and up to 200 ft (61 m) in length. The module contains one or two flat waterbags similar to a waterbed. The bags rest on a layer of insulation or bed of sand inside concrete or fiberglass curbs. The bag is protected against damage and heat loss by greenhouse-type glazing. A typical 200 ft [times] 16 ft (61 m [times] 5 m) pond, filled to a 4 in. (10 cm) depth, holds approximately 8,000 gallons (30 m[sup 3]) of water.

  1. Balancing Teaching with Other Responsibilities: Integrating Roles or Feeding Alligators.

    ERIC Educational Resources Information Center

    Colbeck, Carol L.

    This study investigated how university research faculty balanced undergraduate teaching with their other professional responsibilities, noting how discipline and rank influenced their efforts to balance their work responsibilities. Interviews with 97 faculty members from the University of Texas at Knoxville, the University of Texas at Austin, and…

  2. The Psychologist's Dilemma: Killing Alligators vs. Draining The Swamp

    ERIC Educational Resources Information Center

    Withers, Thomas

    1973-01-01

    Analyzes the problems of the school psychologist, his relationship with the school as a whole as well as with individual children, and the effect teachers can have on child psychological development. (RK)

  3. Tupinambis merianae as nest predators of crocodilians and turtles in Florida, USA

    USGS Publications Warehouse

    Mazzotti, Frank J.; McEachern, Michelle A.; Rochford, Michael; Reed, Robert; Ketterlin Eckles, Jennifer; Vinci, Joy; Edwards, Jake; Wasilewki, Joseph

    2015-01-01

    Tupinambis merianae, is a large, omnivorous tegu lizard native to South America. Two populations of tegus are established in the state of Florida, USA, but impacts to native species are poorly documented. During summer 2013, we placed automated cameras overlooking one American alligator (Alligator mississippiensis) nest, which also contained a clutch of Florida red-bellied cooter (Pseudemys nelsoni) eggs, and one American crocodile (Crocodylus acutus) nest at a site in southeastern Florida where tegus are established. We documented tegu activity and predation on alligator and turtle eggs at the alligator nest, and tegu activity at the crocodile nest. Our finding that one of the first two crocodilian nests to be monitored was depredated by tegus suggests that tegus should be further evaluated as a threat to nesting reptiles in Florida.

  4. 78 FR 14817 - Endangered Species; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-07

    ... Heads of Executive Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR... applicant over a 5-year period. Species: Chinese alligator (Alligator sinensis) Nile crocodile (Crocodylus... (Chelonoidis nigra) Radiated tortoise (Astrochelys radiata) Chinese alligator (Alligator sinensis)...

  5. "Equability," continentality, and Tertiary "climate": The crocodilian perspective

    NASA Astrophysics Data System (ADS)

    Markwick, Paul J.

    1994-07-01

    The distributions of fossil crocodilians are used to examine North American continental paleoclimates for four time periods in the Cenozoic. Control groups provide a qualitative means of examining the completeness of the record and thus the validity of crocodilian patterns. By analogy with the range of the extant American alligator, Alligator mississippiensis, the patterns imply that mid- to high-latitude continental interiors during the Eocene and Miocene did not undergo seasonal temperature extremes as great as those observed in such areas today. This is compatible with the paleobotanical data. During both the late Oligocene and the Pleistocene (times of major glaciation), crocodilians were restricted to more maritime localities.

  6. Presence of Breeding Birds Improves Body Condition for a Crocodilian Nest Protector

    PubMed Central

    Nell, Lucas A.; Frederick, Peter C.; Mazzotti, Frank J.; Vliet, Kent A.; Brandt, Laura A.

    2016-01-01

    Ecological associations where one species enhances habitat for another nearby species (facilitations) shape fundamental community dynamics and can promote niche expansion, thereby influencing how and where species persist and coexist. For the many breeding birds facing high nest-predation pressure, enemy-free space can be gained by nesting near more formidable animals for physical protection. While the benefits to protected species seem well documented, very few studies have explored whether and how protector species are affected by nest protection associations. Long-legged wading birds (Pelecaniformes and Ciconiiformes) actively choose nesting sites above resident American alligators (Alligator mississippiensis), apparently to take advantage of the protection from mammalian nest predators that alligator presence offers. Previous research has shown that wading bird nesting colonies could provide substantial food for alligators in the form of dropped chicks. We compared alligator body condition in similar habitat with and without wading bird nesting colonies present. Alligator morphometric body condition indices were significantly higher in colony than in non-colony locations, an effect that was statistically independent of a range of environmental variables. Since colonially nesting birds and crocodilians co-occur in many tropical and subtropical wetlands, our results highlight a potentially widespread keystone process between two ecologically important species-groups. These findings suggest the interaction is highly beneficial for both groups of actors, and illustrate how selective pressures may have acted to form and reinforce a strongly positive ecological interaction. PMID:26934602

  7. Presence of Breeding Birds Improves Body Condition for a Crocodilian Nest Protector.

    PubMed

    Nell, Lucas A; Frederick, Peter C; Mazzotti, Frank J; Vliet, Kent A; Brandt, Laura A

    2016-01-01

    Ecological associations where one species enhances habitat for another nearby species (facilitations) shape fundamental community dynamics and can promote niche expansion, thereby influencing how and where species persist and coexist. For the many breeding birds facing high nest-predation pressure, enemy-free space can be gained by nesting near more formidable animals for physical protection. While the benefits to protected species seem well documented, very few studies have explored whether and how protector species are affected by nest protection associations. Long-legged wading birds (Pelecaniformes and Ciconiiformes) actively choose nesting sites above resident American alligators (Alligator mississippiensis), apparently to take advantage of the protection from mammalian nest predators that alligator presence offers. Previous research has shown that wading bird nesting colonies could provide substantial food for alligators in the form of dropped chicks. We compared alligator body condition in similar habitat with and without wading bird nesting colonies present. Alligator morphometric body condition indices were significantly higher in colony than in non-colony locations, an effect that was statistically independent of a range of environmental variables. Since colonially nesting birds and crocodilians co-occur in many tropical and subtropical wetlands, our results highlight a potentially widespread keystone process between two ecologically important species-groups. These findings suggest the interaction is highly beneficial for both groups of actors, and illustrate how selective pressures may have acted to form and reinforce a strongly positive ecological interaction. PMID:26934602

  8. PLASMA STEROID CONCENTRATIONS AND MALE PHALLUS SIZE IN JUVENILE ALLIGATORS FROM SEVEN FLORIDA LAKES. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  9. Population structure of the alligator snapping turtle, macrochelys temminckii, on the western edge of its distribution

    USGS Publications Warehouse

    Riedle, J.D.; Shipman, P.A.; Fox, S. F.; Hackler, J.C.; Lesie, D.M., Jr.

    2008-01-01

    A mark-recapture project on Macrochelys temminckii was conducted between 1997 and 2000 at Sequoyah National Wildlife Refuge, Muskogee and Sequoyah counties, in eastern Oklahoma. Turtles were captured in all streams and exhibited equal sex ratios, marked sexual-size dimorphism, and population densities between 28 and 34 animals per km stretch of stream. There was evidence of past population perturbations, with very few large adults captured, and a cohort of subadults highly underrepresented. ?? 2008 Chelonian Research Foundation.

  10. “Patterns of morphological variation of alligator weed (Alternanthera philoxeroides): from native to invasive regions”

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The damage caused by biological invasions has traditionally been thought to result from alien species taking advantage of ecological differences between the native and introduced regions. In contrast, evidence is increasing that invasive plants can undergo rapid adaptive evolution during the process...

  11. Reading Is Fun--with a Keyboard, a Hat, and an Alligator.

    ERIC Educational Resources Information Center

    Prinz, Philip M.; Nelson, Keith E.

    1984-01-01

    A program at the Pennsylvania School for the Deaf uses microcomputers to help students initiate communication and play an active role in deciding the topic of communication and the way the lesson proceeds. Preliminary results suggest the program can enhance reading skills as well as broader aspects of language use. (CL)

  12. REPRODUCTIVE TOXINS AND ALLIGATOR ABNORMALITIES AT LAKE APOPKA, FLORIDA. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. Babies, Dogs, Alligators, Fast Cars, and Dirty Socks: Just Another Day in Kindergarten.

    ERIC Educational Resources Information Center

    Thomas, Grace Gilliard

    Fundamental aspects of the play behavior of kindergarten children are illustrated in five vignettes. Aspects include the function of smiles in play, sex differences in verbal and physical aggression, the simultaneous occurrence of flignt and fantasy in the play of boys, successful nonverbal participation in play, gender stereotypes, the sequencing…

  14. Radionuclide migration at the Koongarra uranium deposit, Northern Australia Lessons from the Alligator Rivers analogue project

    NASA Astrophysics Data System (ADS)

    Payne, Timothy E.; Airey, Peter L.

    The Koongarra uranium deposit in Northern Australia provides a ‘natural analogue’ for processes that are of relevance for assessing the safety of radioactive waste disposal. In an international project extending over two decades, the Koongarra ore body was studied to increase the understanding of radionuclide migration and retention mechanisms that might occur in the vicinity of a geological repository. The research effort included extensive characterisation of the geological, hydrological and geochemical conditions at the site. Patterns of the distribution of radionuclides (predominantly members of the 238U decay chain, but also the rare isotopes 239Pu, 99Tc and 129I) were studied in both solid and groundwater phases. The project included detailed studies of uranium adsorption on mineral surfaces, and of subsequent processes that may lead to long-term uranium immobilisation. Numerous models for uranium migration were developed during the project. This paper provides a comprehensive review of the research at Koongarra, and assesses the value of the site for integrating the results of a complex series of laboratory, modelling and field studies. The insights gained from this review of the Koongarra project may assist in maximising the potential scientific benefit of future natural analogue studies.

  15. Phenotypic variation and water selection potential in the stem structure of invasive alligator weed

    NASA Astrophysics Data System (ADS)

    Du, Leshan; Yang, Beifen; Guan, Wenbin; Li, Junmin

    2016-02-01

    The morphological and anatomical characteristics of stems have been found to be related to drought resistance in plants. Testing the phenotypic selection of water availability on stem anatomical traits would be useful for exploring the evolutionary potential of the stem in response to water availability. To test the phenotypic variation of the stem anatomical traits of an invasive plant in response to water availability, we collected a total of 320 individuals of Alternanthera philoxeroides from 16 populations from terrestrial and aquatic habitats in 8 plots in China and then analyzed the variation, differentiation, plasticity and selection potential of water availability on the stem anatomical traits. We found that except for the thickness of the cortex, all of the examined phenotypic parameters of the A. philoxeroides stem were significantly and positively correlated with soil water availability. The phenotypic differentiation coefficient for all of the anatomical structural parameters indicated that most of the variation existed between habitats within the same plot, whereas there was little variation among plots or among individuals within the same habitat except for variation in the thickness of the cortex. A significant phenotypic plasticity response to water availability was found for all of the anatomical traits of A. philoxeroides stem except for the thickness of the cortex. The associations between fitness and some of the anatomical traits, such as the stem diameter, the cortex area-to-stem area ratio, the pith cavity area-to-stem area ratio and the density of vascular bundles, differed with heterogeneous water availability. In both the aquatic and terrestrial habitats, no significant directional selection gradient was found for the stem diameter, the cortex area-to-stem area ratio or the density of vascular bundles. These results indicated that the anatomical structure of the A. philoxeroides stem may play an important role in the adaptation to changes in water availability.

  16. Cytogenetic effect of Alternanthera philoxeroides (alligator weed) on Agasicles hygrophila (Coleoptera: Chrysomelidae) in its native range

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant polyploidy potentially affects plant-insect interactions; however, its effect on insect fitness remains largely unexplored. Alternanthera philoxeroides is a South American amphibious Amaranthaceae, which invades aquatic and terrestrial habitats. Different morphotypes and cytotypes were identif...

  17. "Alligator Eats Cookie": Acquisition of Writing and Reading Skills by Deaf Children Using the Microcomputer.

    ERIC Educational Resources Information Center

    Prinz, Philip M.; Nelson, Keith E.

    1985-01-01

    Reports research which investigated the effects of microcomputer technology on the acquisition of writing and reading skills in 32 deaf children. The learning mechanism underlying the instructional system used is responsive, interactional and exploratory, reflective of the way most children acquire a first language. (SED)

  18. Like Alligators Bobbing for Poodles? A Critical Discussion of Education, ADHD and the Biopsychosocial Perspective

    ERIC Educational Resources Information Center

    Cooper, Paul

    2008-01-01

    ADHD (Attention Deficit/Hyperactivity Disorder) continues to be a controversial issue among some educationalists. This paper argues that negativity towards the ADHD concept shown by some antagonists is based on outdated thinking and a lack of understanding of the diagnosis and the biopsychosocial paradigm through which it can be usefully…

  19. Beyond the Egg Carton Alligator: To Recycle Is To Recall and Restore.

    ERIC Educational Resources Information Center

    Congdon, Kristin G.

    2000-01-01

    States that the art of recycling has more to do with connecting people with objects, traditions, and rituals than sustaining the natural environment. Discusses some lessons learned in four categories: (1) recycling as self-sufficiency; (2) recycling as renewal; (3) recycling as a spiritual activity; and (4) recycling as aesthetic transformation.…

  20. Hormone Binding to Recombinant Estrogen Receptors from Human, Alligator, Quail, Salamander, and Fathead Minnow

    EPA Science Inventory

    In this work, a 96-well plate estrogen receptor binding assay was developed to facilitate the direct comparison of chemical binding to full-length recombinant estrogen receptors across vertebrate classes. Receptors were generated in a baculovirus expression system. This approach ...

  1. ALLIGATORS AND ENDOCRINE DISRUPTING CONTAMINANTS: A CURRENT PERSPECTIVE.AMERICAN ZOOLOGIST

    EPA Science Inventory

    Many xenobiotic compounds introduced into the environment by human activity have been shown to adversely affect wildlife. Reproductive disorders in wildlife include altered fertility, reduced viability of offspring, impaired hormone secretion or activity and modified reproductive...

  2. The research component of specialist registration--a question of alligators and swamps? A personal view.

    PubMed

    Aldous, C M; Adhikari, M; Rout, C C

    2015-01-01

    The recent implementation of the research requirement for specialist registration presents difficulties with regard to the provision of research supervision, particularly in those medical schools that previously followed the path of qualification via the Colleges of Medicine of South Africa examinations. The differences between the requirements for research supervision as stated in the Health Professions Council of South Africa memorandum and those of the Committee for Higher Education are causing disparities between medical schools similar to those that led to the memorandum in the first place. While the research component of specialist training can only improve the quality of both patient care and academic endeavour, it requires an enormous investment of time on the part of both the specialist trainees and their supervisors. In order to deal with this, specific issues outlined in the article need to be addressed. PMID:26046156

  3. "Patterns of morphological variation of alligator weed (Alternanthera philoxeroides): from native to invasive regions"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The damage caused by biological invasions has traditionally been thought to result from alien species taking advantage of ecological differences between the native and introduced regions. In contrast, evidence is increasing that invasive plants can undergo rapid adaptive evolution during the process...

  4. Chompy: an infestation of MITE-like repetitive elements in the crocodilian genome.

    PubMed

    Ray, David A; Hedges, Dale J; Herke, Scott W; Fowlkes, Justin D; Barnes, Erin W; LaVie, Daniel K; Goodwin, Lindsey M; Densmore, Llewellyn D; Batzer, Mark A

    2005-12-01

    Interspersed repeats are a major component of most eukaryotic genomes and have an impact on genome size and stability, but the repetitive element landscape of crocodilian genomes has not yet been fully investigated. In this report, we provide the first detailed characterization of an interspersed repeat element in any crocodilian genome. Chompy is a putative miniature inverted-repeat transposable element (MITE) family initially recovered from the genome of Alligator mississippiensis (American alligator) but also present in the genomes of Crocodylus moreletii (Morelet's crocodile) and Gavialis gangeticus (Indian gharial). The element has all of the hallmarks of MITEs including terminal inverted repeats, possible target site duplications, and a tendency to form secondary structures. We estimate the copy number in the alligator genome to be approximately 46,000 copies. As a result of their size and unique properties, Chompy elements may provide a useful source of genomic variation for crocodilian comparative genomics. PMID:16183215

  5. Fusion Patterns in the Skulls of Modern Archosaurs Reveal That Sutures Are Ambiguous Maturity Indicators for the Dinosauria.

    PubMed

    Bailleul, Alida M; Scannella, John B; Horner, John R; Evans, David C

    2016-01-01

    The sutures of the skulls of vertebrates are generally open early in life and slowly close as maturity is attained. The assumption that all vertebrates follow this pattern of progressive sutural closure has been used to assess maturity in the fossil remains of non-avian dinosaurs. Here, we test this assumption in two members of the Extant Phylogenetic Bracket of the Dinosauria, the emu, Dromaius novaehollandiae and the American alligator, Alligator mississippiensis, by investigating the sequence and timing of sutural fusion in their skulls. As expected, almost all the sutures in the emu skull progressively close (i.e., they get narrower) and then obliterate during ontogeny. However, in the American alligator, only two sutures out of 36 obliterate completely and they do so during embryonic development. Surprisingly, as maturity progresses, many sutures of alligators become wider in large individuals compared to younger, smaller individuals. Histological and histomorphometric analyses on two sutures and one synchondrosis in an ontogenetic series of American alligator confirmed our morphological observations. This pattern of sutural widening might reflect feeding biomechanics and dietary changes through ontogeny. Our findings show that progressive sutural closure is not always observed in extant archosaurs, and therefore suggest that cranial sutural fusion is an ambiguous proxy for assessing maturity in non-avian dinosaurs. PMID:26862766

  6. Fusion Patterns in the Skulls of Modern Archosaurs Reveal That Sutures Are Ambiguous Maturity Indicators for the Dinosauria

    PubMed Central

    Bailleul, Alida M.; Scannella, John B.; Horner, John R.; Evans, David C.

    2016-01-01

    The sutures of the skulls of vertebrates are generally open early in life and slowly close as maturity is attained. The assumption that all vertebrates follow this pattern of progressive sutural closure has been used to assess maturity in the fossil remains of non-avian dinosaurs. Here, we test this assumption in two members of the Extant Phylogenetic Bracket of the Dinosauria, the emu, Dromaius novaehollandiae and the American alligator, Alligator mississippiensis, by investigating the sequence and timing of sutural fusion in their skulls. As expected, almost all the sutures in the emu skull progressively close (i.e., they get narrower) and then obliterate during ontogeny. However, in the American alligator, only two sutures out of 36 obliterate completely and they do so during embryonic development. Surprisingly, as maturity progresses, many sutures of alligators become wider in large individuals compared to younger, smaller individuals. Histological and histomorphometric analyses on two sutures and one synchondrosis in an ontogenetic series of American alligator confirmed our morphological observations. This pattern of sutural widening might reflect feeding biomechanics and dietary changes through ontogeny. Our findings show that progressive sutural closure is not always observed in extant archosaurs, and therefore suggest that cranial sutural fusion is an ambiguous proxy for assessing maturity in non-avian dinosaurs. PMID:26862766

  7. Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator

    USGS Publications Warehouse

    Rosenblatt, Adam E.; Nifong, James C.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael S.; Jeffery, Brian M.; Elsey, Ruth M.; Decker, Rachel A.; Silliman, Brian R.; Guillette, Louis J., Jr.; Lowers, Russell H.; Larson, Justin C.

    2015-01-01

    Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators (Alligator mississippiensis), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability.

  8. Factors affecting individual foraging specialization and temporal diet stability across the range of a large "generalist" apex predator.

    PubMed

    Rosenblatt, Adam E; Nifong, James C; Heithaus, Michael R; Mazzotti, Frank J; Cherkiss, Michael S; Jeffery, Brian M; Elsey, Ruth M; Decker, Rachel A; Silliman, Brian R; Guillette, Louis J; Lowers, Russell H; Larson, Justin C

    2015-05-01

    Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators (Alligator mississippiensis), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability. PMID:25645268

  9. 77 FR 49453 - Endangered Species; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ... Heads of Executive Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR... crocodile (Osteolaemus tetraspis) Chinese alligator (Alligator sinensis) Cuban crocodile...

  10. 77 FR 26779 - Endangered Species; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ... Heads of Executive Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR... nigripes) Chinese alligator (Alligator sinensis) Applicant: Charles Musgrave, Pilot Point, TX;...

  11. 77 FR 70457 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR 4685; January 26, 2009... oedipus) Leopard (Panthera pardus) Chinese alligator (Alligator sinensis) Aruba Island...

  12. 78 FR 44961 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-25

    ... Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR 4685; January 26, 2009... alligator (Alligator sinensis), to enhance their propagation or survival. This notification...

  13. INTERACTION OF ENVIRONMENTAL CHEMICALS WITH THE ESTROGEN AND PROGESTERONE RECEPTORS FROM THE OVIDUCT OF THE AMERICAN ALLIGATOR. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. Total Quality & Basic Skills. The TQ Castle--Using Basic Skills Development to Evade Alligators in the Moat.

    ERIC Educational Resources Information Center

    Lewe, Glenda

    1994-01-01

    Key skills required in the total quality workplace are cross-functional teaming, interpreting charts/graphs, oral communication, brainstorming, understanding cause/effect, categorizing ideas, critical pathing, formulating suggestions, analyzing the needs of internal and external customers, and writing status reports. (SK)

  15. Molecular alligator clips: a theoretical study of adsorption of S, Se and S H on Au(111)

    NASA Astrophysics Data System (ADS)

    Mankefors, S.; Grigoriev, A.; Wendin, G.

    2003-08-01

    For the binding of thiols to Au, the Au-S interaction is decisive for the geometry, bonding strength and transmissivity of the metal-molecule interface. Using ab initio methods we investigate the adsorption of sulfur (S) on the Au(111) surface for different coverages between 0.25 and 1.0 monolayers (ML). Corresponding geometries with adsorbed Se are included to establish possible differences between S- and Se-based metal-molecule interfaces. We furthermore investigate hydrogenation of sulfur-covered Au(111) surfaces to establish the energetics and resulting geometry of adsorption of S-H groups on clean Au(111), using it as a simple model system. For the relatively low coverage of 0.25 ML the S and Se atoms are found to prefer the in-hollow sites, with Se displaying a substantially stronger bond. Increasing the coverage leads to depletion of available free charge in the gold surface, which weakens the bonds to the S (Se). Due to the more extensive hybridization, Se is more insensitive to the exact geometry, and the stacking fault position only costs 0.04 eV. At even higher coverage (0.75 ML) the adsorbed atoms hybridize internally and form triatomic molecules situated on top of the Au surface atoms. In S (Se) rich environments this turns out to be the most stable configuration investigated, while in S (Se) poor conditions the surface will adsorb all available S (Se). Forcing the system to adsorb atoms beyond this coverage increases the total energy. For all physically realizable coverages the Au-Se bond is found to be geq0.25 eV stronger than the corresponding Au-S bond. The Se bond also displays a higher degree of metallicity and should be expected to make a better head group for thiols, for example; this is relevant for both bonding and conductivity. Turning to the hydrogenated S systems we find that surfaces with a high coverage of S only weakly bind H at low partial hydrogenation, while H adsorption in systems with medium and low S concentrations is found to be energetically stable by around 0.3 eV per H atom. The adsorption geometry is sensitive to the concentration: exposed to free S, the system will increase the S coverage and expel H.

  16. EFFECTS OF INCUBATION TEMPERATURE AND ESTROGEN EXPOSURE ON AROMATASE ACTIVITY IN THE BRAIN AND GONADS OF EMBRYONIC ALLIGATORS

    EPA Science Inventory

    During embryogenesis, incubation temperature and the hormonal environment influence gonadal differentiation of some reptiles, including all crocodilians. Current evidence suggests that aromatase, the enzyme that converts androgens to estrogens, has a role in sexual differentiatio...

  17. SERUM CONCENTRATIONS OF VARIOUS ENVIRONMENTAL CONTAMINANTS AND THEIR RELATIONSHIP TO SEX STEROID CONCENTRATIONS IN THE AMERICAN ALLIGATOR. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  18. IN VITRO SYNERGISTIC INTERACTION OF ALLIGATOR AND HUMAN ESTROGEN RECEPTORS WITH COMBINATIONS OF ENVIRONMENTAL CHEMICALS. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  19. Geochemistry, mineralization, structure, and permeability of a normal-fault zone, Casino mine, Alligator Ridge district, north central Nevada

    NASA Astrophysics Data System (ADS)

    Hammond, K. Jill; Evans, James P.

    2003-05-01

    We examine the geochemical signature and structure of the Keno fault zone to test its impact on the flow of ore-mineralizing fluids, and use the mined exposures to evaluate structures and processes associated with normal fault development. The fault is a moderately dipping normal-fault zone in siltstone and silty limestone with 55-100 m of dip-slip displacement in north-central Nevada. Across-strike exposures up to 180 m long, 65 m of down-dip exposure and 350 m of along-strike exposure allow us to determine how faults, fractures, and fluids interact within mixed-lithology carbonate-dominated sedimentary rocks. The fault changes character along strike from a single clay-rich slip plane 10-20 mm thick at the northern exposure to numerous hydrocarbon-bearing, calcite-filled, nearly vertical slip planes in a zone 15 m wide at the southern exposure. The hanging wall and footwall are intensely fractured but fracture densities do not vary markedly with distance from the fault. Fault slip varies from pure dip-slip to nearly pure strike-slip, which suggests that either slip orientations may vary on faults in single slip events, or stress variations over the history of the fault caused slip vector variations. Whole-rock major, minor, and trace element analyses indicate that Au, Sb, and As are in general associated with the fault zone, suggesting that Au- and silica-bearing fluids migrated along the fault to replace carbonate in the footwall and adjacent hanging wall rocks. Subsequent fault slip was associated with barite and calcite and hydrocarbon-bearing fluids deposited at the southern end of the fault. No correlation exists at the meter or tens of meter scale between mineralization patterns and fracture density. We suggest that the fault was a combined conduit-barrier system in which the fault provides a critical connection between the fluid sources and fractures that formed before and during faulting. During the waning stages of deposit formation, the fault behaved as a localized conduit to hydrocarbon-bearing calcite veins. The results of this study show that fault-zone character may change dramatically over short, deposit- or reservoir-scale distances. The presence of damage zones may not be well correlated at the fine scale with geochemically defined regions of the fault, even though a gross spatial correlation may exist.

  20. SEA you later alli-GATOR – a dynamic regulator of the TORC1 stress response pathway

    PubMed Central

    Dokudovskaya, Svetlana; Rout, Michael P.

    2015-01-01

    ABSTRACT Cells constantly adapt to various environmental changes and stresses. The way in which nutrient and stress levels in a cell feed back to control metabolism and growth are, unsurprisingly, extremely complex, as responding with great sensitivity and speed to the ‘feast or famine, slack or stress’ status of its environment is a central goal for any organism. The highly conserved target of rapamycin complex 1 (TORC1) controls eukaryotic cell growth and response to a variety of signals, including nutrients, hormones and stresses, and plays the key role in the regulation of autophagy. A lot of attention has been paid recently to the factors in this pathway functioning upstream of TORC1. In this Commentary, we focus on a major, newly discovered upstream regulator of TORC1 – the multiprotein SEA complex, also known as GATOR. We describe the structural and functional features of the yeast complex and its mammalian homolog, and their involvement in the regulation of the TORC1 pathway and TORC1-independent processes. We will also provide an overview of the consequences of GATOR deregulation in cancer and other diseases. PMID:25934700

  1. New species of Gymnocarena Hering (Diptera: Tephritidae) from Eastern North America and Guatemala, and the redescription of G. mississippiensis Norrbom

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe three new species of fruit flies (Tephritidae: Tephritinae), Gymnocarena defoei sp. n. and G. norrbomi sp. n., from eastern North America and G. monzoni sp. n. from Guatemala, and redescribe G. mississippiensis Norrbom. Gymnocarena monzoni is the first species to be recorded from Guatema...

  2. Record length, mass, and clutch size in the nonindigenous Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), in Florida

    USGS Publications Warehouse

    Krysko, Kenneth L.; Hart, Kristen M.; Smith, Brian J.; Selby, Thomas H.; Cherkiss, Michael S.; Coutu, Nicholas T.; Reichart, Rebecca M.; Nuñez, Leroy P.; Mazzotti, Frank J.; Snow, Ray W.

    2012-01-01

    The Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), is indigenous to northern India,east to southern China, and south to Vietnam and a few islands in Indonesia (Barker and Barker 2008, Reed and Rodda 2009). This species has been introduced since at least 1979 in southern Florida, USA, where it likely began reproducing and became established during the 1980s (Meshaka et al. 2000, Snowet al. 2007b,Kraus 2009, Krysko et al. 2011, Willson et al. 2011). Python bivittatus has been documented in Florida consuming a variety of mammals and birds, and the American Alligator(Alligator mississippiensis) (Snowet al. 2007a, 2007b; Harvey et al. 2008; Rochford et al. 2010b; Holbrook and Chesnes 2011), many of which are protected species. Herein, we provide details on two of the largest known wild P. bivittatus in Florida to date, including current records on length,mass,clutch size, and diet.

  3. Technique for the collection of clear urine from the Nile crocodile (Crocodylus niloticus).

    PubMed

    Myburgh, Jan G; Huchzermeyer, Fritz W; Soley, John T; Booyse, Dirk G; Groenewald, Herman B; Bekker, Lizette C; Iguchi, Taisen; Guillette, Louis J

    2012-01-01

    Urine samples can be a very useful diagnostic tool for the evaluation of animal health. In this article, a simple technique to collect urine from the Nile crocodile (Crocodylus niloticus) was described, based on a similar unpublished technique developed for the American alligator (Alligator mississippiensis) using a canine urinary catheter. With this technique, it was possible to collect relatively clean urine samples from Nile crocodiles of different sizes using canine urinary catheters or small diameter stomach tubes. Based on the gross anatomical features of the cloaca of the Nile crocodile, it was confirmed that urine accumulates in a chamber consisting of the urodeum and coprodeum. Faecal material is stored temporarily in the very short rectum, which is separated from the urinary chamber by the rectocoprodeal sphincter. PMID:23327128

  4. A repeated-measures analysis of the effects of soft tissues on wrist range of motion in the extant phylogenetic bracket of dinosaurs: Implications for the functional origins of an automatic wrist folding mechanism in Crocodilia.

    PubMed

    Hutson, Joel David; Hutson, Kelda Nadine

    2014-07-01

    A recent study hypothesized that avian-like wrist folding in quadrupedal dinosaurs could have aided their distinctive style of locomotion with semi-pronated and therefore medially facing palms. However, soft tissues that automatically guide avian wrist folding rarely fossilize, and automatic wrist folding of unknown function in extant crocodilians has not been used to test this hypothesis. Therefore, an investigation of the relative contributions of soft tissues to wrist range of motion (ROM) in the extant phylogenetic bracket of dinosaurs, and the quadrupedal function of crocodilian wrist folding, could inform these questions. Here, we repeatedly measured wrist ROM in degrees through fully fleshed, skinned, minus muscles/tendons, minus ligaments, and skeletonized stages in the American alligator Alligator mississippiensis and the ostrich Struthio camelus. The effects of dissection treatment and observer were statistically significant for alligator wrist folding and ostrich wrist flexion, but not ostrich wrist folding. Final skeletonized wrist folding ROM was higher than (ostrich) or equivalent to (alligator) initial fully fleshed ROM, while final ROM was lower than initial ROM for ostrich wrist flexion. These findings suggest that, unlike the hinge/ball and socket-type elbow and shoulder joints in these archosaurs, ROM within gliding/planar diarthrotic joints is more restricted to the extent of articular surfaces. The alligator data indicate that the crocodilian wrist mechanism functions to automatically lock their semi-pronated palms into a rigid column, which supports the hypothesis that this palmar orientation necessitated soft tissue stiffening mechanisms in certain dinosaurs, although ROM-restricted articulations argue against the presence of an extensive automatic mechanism. Anat Rec, 297:1228-1249, 2014. © 2014 Wiley Periodicals, Inc. PMID:24664936

  5. Characterization of Organics Consistent with β-Chitin Preserved in the Late Eocene Cuttlefish Mississaepia mississippiensis

    PubMed Central

    Weaver, Patricia G.; Doguzhaeva, Larisa A.; Lawver, Daniel R.; Tacker, R. Christopher; Ciampaglio, Charles N.; Crate, Jon M.; Zheng, Wenxia

    2011-01-01

    Background Preservation of original organic components in fossils across geological time is controversial, but the potential such molecules have for elucidating evolutionary processes and phylogenetic relationships is invaluable. Chitin is one such molecule. Ancient chitin has been recovered from both terrestrial and marine arthropods, but prior to this study had not been recovered from fossil marine mollusks. Methodology/Principal Findings Organics consistent with β-chitin are recovered in cuttlebones of Mississaepia mississippiensis from the Late Eocene (34.36 million years ago) marine clays of Hinds County, Mississippi, USA. These organics were determined and characterized through comparisons with extant taxa using Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS), Field Emission Scanning Electron Microscopy (Hyperprobe), Fourier Transmission Infrared Spectroscopy (FTIR) and Immunohistochemistry (IHC). Conclusions/Significance Our study presents the first evidence for organics consistent with chitin from an ancient marine mollusk and discusses how these organics have been degraded over time. As mechanisms for their preservation, we propose that the inorganic/organic lamination of the cuttlebone, combined with a suboxic depositional environment with available free Fe2+ ions, inhibited microbial or enzymatic degradation. PMID:22132239

  6. Androgynous rex - the utility of chevrons for determining the sex of crocodilians and non-avian dinosaurs.

    PubMed

    Erickson, Gregory M; Kristopher Lappin, A; Larson, Peter

    2005-01-01

    The sex of non-avian dinosaurs has been inferred on numerous occasions using a variety of anatomical criteria, but the efficacy of none has been proven. Nearly 50 years ago Romer suggested that the cranial-most or first chevron in the tails of some reptiles, including crocodilians, is sexually dimorphic. Recent work on this subject purportedly substantiated that the female first chevron articulates in a more caudal position than in males. Furthermore, it was concluded that this element is shorter in females. These phenotypic attributes theoretically provide a broader cloacal passageway for eggs by ovipositing females and a greater attachment area for male "penile retractor muscles". Because theropod dinosaurs such as Tyrannosaurus rex presumably show similar variation in chevron anatomy, the same criteria has been advocated for sexing dinosaurs. We tested the neontological model for the chevron sexual dimorphism hypothesis using a skeletonized growth series of American alligators (Alligator mississippiensis) of known sex. No statistical support for the hypothesis was found. Furthermore, analysis of a diversity of crocodilian taxa from museum collections revealed similar findings suggesting the alligator results are not taxon specific. Study of well-preserved tyrannosaurid dinosaurs in museum collections showed nearly invariant chevron positioning like that seen in crocodilians. This suggests the usefulness of chevron anatomy for sexing dinosaurs is tenuous. PMID:16351976

  7. 30 CFR Appendix to Part 253 - List of U.S. Geological Survey Topographic Maps

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... Florida (1:24,000 scale): Allanton; Alligator Bay; Anna Maria; Apalachicola; Aripeka; Bayport; Beacon...): Alligator Point; Barataria Pass; Bastian Bay; Bay Batiste; Bay Coquette; Bay Courant; Bay Dosgris;...

  8. 30 CFR Appendix to Part 253 - List of U.S. Geological Survey Topographic Maps

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...; Tustin; Venice; Ventura; White Ledge Peak. Florida (1:24,000 scale): Allanton; Alligator Bay; Anna Maria...; Yankeetown. Louisiana (1:24,000 scale): Alligator Point; Barataria Pass; Bastian Bay; Bay Batiste;...

  9. 30 CFR Appendix to Part 553 - List of U.S. Geological Survey Topographic Maps

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Florida (1:24,000 scale): Allanton; Alligator Bay; Anna Maria; Apalachicola; Aripeka; Bayport; Beacon...): Alligator Point; Barataria Pass; Bastian Bay; Bay Batiste; Bay Coquette; Bay Courant; Bay Dosgris;...

  10. 30 CFR Appendix to Part 553 - List of U.S. Geological Survey Topographic Maps

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... Florida (1:24,000 scale): Allanton; Alligator Bay; Anna Maria; Apalachicola; Aripeka; Bayport; Beacon...): Alligator Point; Barataria Pass; Bastian Bay; Bay Batiste; Bay Coquette; Bay Courant; Bay Dosgris;...

  11. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, and guillotine shears (Order...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... include other types of shearing machines, using a different form of shearing action, such as alligator... machines, using a different form of shearing action, such as alligator shears or circular shears....

  12. 30 CFR Appendix to Part 553 - List of U.S. Geological Survey Topographic Maps

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Florida (1:24,000 scale): Allanton; Alligator Bay; Anna Maria; Apalachicola; Aripeka; Bayport; Beacon...): Alligator Point; Barataria Pass; Bastian Bay; Bay Batiste; Bay Coquette; Bay Courant; Bay Dosgris;...

  13. 50 CFR 32.37 - Louisiana.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... into the water. 3. We prohibit commercial fishing. 4. We prohibit the taking of alligator snapping... times. 4. The use of trotlines, limblines, slat traps, gar sets, nets or alligator lines is prohibited.... 3. We prohibit the use of trotlines, limblines, slat traps, gar sets, nets, or alligator lines...

  14. 50 CFR 32.37 - Louisiana.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... into the water. 3. We prohibit commercial fishing. 4. We prohibit the taking of alligator snapping... times. 4. The use of trotlines, limblines, slat traps, gar sets, nets or alligator lines is prohibited.... 3. We prohibit the use of trotlines, limblines, slat traps, gar sets, nets, or alligator lines...

  15. 77 FR 9635 - Notice of Availability of a Draft Environmental Impact Statement in Cooperation With the North...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ... replacement of the Lindsay C. Warren Bridge over the Alligator River. The purpose of the proposed project is... Highway System, and to maintain a bridge across the Alligator River that meets the needs of highway users... Resources, N.C. Division of Marine Fisheries, and the Alligator River National Wildlife Refuge. During...

  16. 50 CFR 17.84 - Special rules-vertebrates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... reported to either the Refuge Manager, Alligator River National Wildlife Refuge, Manteo, North Carolina... (c) (2) through (7) of this section. (9)(i) The Alligator River reintroduction site is within the...-breeding facility. (11) The status of the Alligator River National Wildlife Refuge project will...

  17. 50 CFR 32.37 - Louisiana.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... into the water. 3. We prohibit commercial fishing. 4. We prohibit the taking of alligator snapping... times. 4. The use of trotlines, limblines, slat traps, gar sets, nets or alligator lines is prohibited.... 3. We prohibit the use of trotlines, limblines, slat traps, gar sets, nets, or alligator lines...

  18. 50 CFR 17.84 - Special rules-vertebrates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... reported to either the Refuge Manager, Alligator River National Wildlife Refuge, Manteo, North Carolina... (c) (2) through (7) of this section. (9)(i) The Alligator River reintroduction site is within the...-breeding facility. (11) The status of the Alligator River National Wildlife Refuge project will...

  19. 50 CFR 32.28 - Florida.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Game Hunting. We allow hunting of alligators on designated areas of the refuge in accordance with... signed refuge alligator hunt permit (signed brochure) while hunting. These brochures are available at the... posted as closed. 3. Consult the refuge manager for current alligator hunt season dates and times. 4....

  20. Size, sex and individual-level behaviour drive intrapopulation variation in cross-ecosystem foraging of a top-predator.

    PubMed

    Nifong, James C; Layman, Craig A; Silliman, Brian R

    2015-01-01

    Large-bodied, top-predators are often highly mobile, with the potential to provide important linkages between spatially distinct food webs. What biological factors contribute to variation in cross-ecosystem movements, however, have rarely been examined. Here, we investigated how ontogeny (body size), sex and individual-level behaviour impacts intrapopulation variation in cross-ecosystem foraging (i.e. between freshwater and marine systems), by the top-predator Alligator mississippiensis. Field surveys revealed A. mississippiensis uses marine ecosystems regularly and are abundant in estuarine tidal creeks (from 0·3 to 6·3 individuals per km of creek, n = 45 surveys). Alligator mississippiensis captured in marine/estuarine habitats were significantly larger than individuals captured in freshwater and intermediate habitats. Stomach content analysis (SCA) showed that small juveniles consumed marine/estuarine prey less frequently (6·7% of individuals) than did large juveniles (57·8%), subadult (73%), and adult (78%) size classes. Isotopic mixing model analysis (SIAR) also suggests substantial variation in use of marine/estuarine prey resources with differences among and within size classes between sexes and individuals (range of median estimates for marine/estuarine diet contribution = 0·05-0·76). These results demonstrate the importance of intrapopulation characteristics (body size, sex and individual specialization) as key determinants of the strength of predator-driven ecosystem connectivity resulting from cross-ecosystem foraging behaviours. Understanding the factors, which contribute to variation in cross-ecosystem foraging behaviours, will improve our predictive understanding of the effects of top-predators on community structure and ecosystem function. PMID:25327480

  1. EFFECT OF ACUTE STRESS ON PLASMA TESTOSTERONE, ESTRADIOL-17B AND CORTICOSTERONE CONCENTRATIONS IN JUVENILE ALLIGATORS LIVING IN CONTROL AND CONTAMINATED LAKES. (R824760)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  2. Phenrica littoralis a potential candidate for the biological control of alligator weed, Alternanthera philoxeroides: redscription of the adult, first description of immature stages and biological notes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flea beetles of aliligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby Systena Chevrolat and Phenrica Bechyne were frequently found on this weed. Phenric...

  3. Influence of group II metals on Radium-226 concentration ratios in the native green plum (Buchanania obovata) from the Alligator Rivers Region, Northern Territory, Australia.

    PubMed

    Medley, Peter; Bollhöfer, Andreas

    2016-01-01

    In this study, uptake of Ra from soil, and the influence of group II metals on Ra uptake, into the stones and edible flesh of the fruit of the wild green plum, Buchanania obovata, was investigated. Selective extraction of the exchangeable fraction of the soil samples was undertaken but was not shown to more reliably predict Ra uptake than total soil Ra activity concentration. Comparison of the group II metal to Ca ratios (i.e. Sr/Ca, Ba/Ca, Ra/Ca) in the flesh with exchangeable Ca shows that Ca outcompetes group II metals for root uptake and that the uptake pathway discriminated against group II metals relative to ionic radius, with uptake of Ca > Sr > Ba > Ra. Flesh and stone analysis showed that movement of group II metals to these components of the plant, after root uptake, was strongly related. This supports the hypothesis that Sr, Ba and Ra are being taken up as analogue elements, and follow the same uptake and translocation pathways, with Ca. Comparison with previously reported data from a native passion fruit supports the use of total soil CRs on natural, undisturbed sites. As exchangeable CRs for Ra reach a saturation value it may be possible to make more precise predictions using selective extraction techniques for contaminated or disturbed sites. PMID:26277654

  4. Macrogeographic genetic variation in broad-snouted caiman (Caiman latirostris).

    PubMed

    Villela, Priscilla Marqui Schmidt; Coutinho, Luiz Lehmann; Piña, Carlos Ignacio; Verdade, Luciano M

    2008-12-01

    Broad-snouted caiman's (Caiman latirostris) geographic distribution comprises one of the widest latitudinal ranges among all crocodilians. In this study we analyzed the relationship between geographic distance (along the species latitudinal range) and genetic differentiation using DNA microsatellite loci developed for C. latirostris and Alligator mississippiensis. The results suggest that there is a consistent relationship between geographic distance and genetic differentiation; however, other biogeographical factors seem to be relevant. The Atlantic Chain (Serra do Mar) seems to be an effective geographic barrier, as well as the relatively narrow (< or =1.5 km) sea channel between Cardoso Island and the continent. In addition, coastal populations seem to have been well connected in recent geological time (Pleistocene 16,000 years ago) all along the eastern Brazilian coast. Further studies should focus on the São Francisco River drainage, which is still poorly known for this species. PMID:18661469

  5. In vivo cranial bone strain and bite force in the agamid lizard Uromastyx geyri

    PubMed Central

    Porro, Laura B.; Ross, Callum F.; Iriarte-Diaz, Jose; O'Reilly, James C.; Evans, Susan E.; Fagan, Michael J.

    2014-01-01

    In vivo bone strain data are the most direct evidence of deformation and strain regimes in the vertebrate cranium during feeding and can provide important insights into skull morphology. Strain data have been collected during feeding across a wide range of mammals; in contrast, in vivo cranial bone strain data have been collected from few sauropsid taxa. Here we present bone strain data recorded from the jugal of the herbivorous agamid lizard Uromastyx geyri along with simultaneously recorded bite force. Principal and shear strain magnitudes in Uromastyx geyri were lower than cranial bone strains recorded in Alligator mississippiensis, but higher than those reported from herbivorous mammals. Our results suggest that variations in principal strain orientations in the facial skeleton are largely due to differences in feeding behavior and bite location, whereas food type has little impact on strain orientations. Furthermore, mean principal strain orientations differ between male and female Uromastyx during feeding, potentially because of sexual dimorphism in skull morphology. PMID:24577443

  6. Tidal salt marshes of the southeast Atlantic Coast: A community profile

    SciTech Connect

    Wiegert, R.G.; Freeman, B.J.

    1990-09-01

    This report is part of a series of community profiles on the ecology of wetland and marine communities. This particular profile considers tidal marshes of the southeastern Atlantic coast, from North Carolina south to northern Florida. Alone among the earth's ecosystems, coastal communities are subjected to a bidirectional flooding sometimes occurring twice each day; this flooding affects successional development, species composition, stability, and productivity. In the tidally influenced salt marsh, salinity ranges from less than 1 ppt to that of seawater. Dominant plant species include cordgrasses (Spartina alterniflora and S. cynosuroides), black needlerush (Juncus romerianus), and salt marsh bulrush (Scirpus robustus). Both terrestrail and aquatic animals occur in salt marshes and include herons, egrets ospreys (Pandion haliaetus), bald eagles (Haliaeetus leucocephalus), alligators (Alligator Mississippiensis), manatees (Trichecus manatus), oysters, mussels, and fiddler crabs. Currently, the only significant direct commercial use of the tidal salt marshes is by crabbers seeking the blue crab Callinectes sapidus, but the marshes are quite important recreationally, aesthetically, and educationally. 151 refs., 45 figs., 6 tabs.

  7. Three crocodilian genomes reveal ancestral patterns of evolution among archosaurs

    PubMed Central

    Green, Richard E; Braun, Edward L; Armstrong, Joel; Earl, Dent; Nguyen, Ngan; Hickey, Glenn; Vandewege, Michael W; St John, John A; Capella-Gutiérrez, Salvador; Castoe, Todd A; Kern, Colin; Fujita, Matthew K; Opazo, Juan C; Jurka, Jerzy; Kojima, Kenji K; Caballero, Juan; Hubley, Robert M; Smit, Arian F; Platt, Roy N; Lavoie, Christine A; Ramakodi, Meganathan P; Finger, John W; Suh, Alexander; Isberg, Sally R; Miles, Lee; Chong, Amanda Y; Jaratlerdsiri, Weerachai; Gongora, Jaime; Moran, Christopher; Iriarte, Andrés; McCormack, John; Burgess, Shane C; Edwards, Scott V; Lyons, Eric; Williams, Christina; Breen, Matthew; Howard, Jason T; Gresham, Cathy R; Peterson, Daniel G; Schmitz, Jürgen; Pollock, David D; Haussler, David; Triplett, Eric W; Zhang, Guojie; Irie, Naoki; Jarvis, Erich D; Brochu, Christopher A; Schmidt, Carl J; McCarthy, Fiona M; Faircloth, Brant C; Hoffmann, Federico G; Glenn, Travis C; Gabaldón, Toni; Paten, Benedict; Ray, David A

    2015-01-01

    To provide context for the diversifications of archosaurs, the group that includes crocodilians, dinosaurs and birds, we generated draft genomes of three crocodilians, Alligator mississippiensis (the American alligator), Crocodylus porosus (the saltwater crocodile), and Gavialis gangeticus (the Indian gharial). We observed an exceptionally slow rate of genome evolution within crocodilians at all levels, including nucleotide substitutions, indels, transposable element content and movement, gene family evolution, and chromosomal synteny. When placed within the context of related taxa including birds and turtles, this suggests that the common ancestor of all of these taxa also exhibited slow genome evolution and that the relatively rapid evolution of bird genomes represents an autapomorphy within that clade. The data also provided the opportunity to analyze heterozygosity in crocodilians, which indicates a likely reduction in population size for all three taxa through the Pleistocene. Finally, these new data combined with newly published bird genomes allowed us to reconstruct the partial genome of the common ancestor of archosaurs providing a tool to investigate the genetic starting material of crocodilians, birds, and dinosaurs. PMID:25504731

  8. Effects of hypoxia on vertebrate blood vessels.

    PubMed

    Russell, Michael J; Dombkowski, Ryan A; Olson, Kenneth R

    2008-03-01

    Hypoxia contracts mammalian respiratory vessels and increases vascular resistance in respiratory tissues of many vertebrates. In systemic vessels these responses vary, hypoxia relaxes mammalian vessels and contracts systemic arteries from cyclostomes. It has been proposed that hypoxic vasoconstriction in cyclostome systemic arteries is the antecedent to mammalian hypoxic pulmonary vasoconstriction, however, phylogenetic characterization of hypoxic responses is lacking. In this study, we characterized the hypoxic response of isolated systemic and respiratory vessels from a variety of vertebrates using standard myography. Pre-gill/respiratory (ventral aorta, afferent branchial artery, pulmonary artery) and post-gill/systemic (dorsal and thoracic aortas, efferent branchial artery) from lamprey (Petromyzon marinus), sandbar shark (Carcharhinus plumbeus), yellowfin tuna (Thunnus albacares), American bullfrog (Rana catesbeiana), American alligator (Alligator mississippiensis), Pekin duck (Anas platyrhynchos domesticus), chicken (Gallus domesticus) and rat (Rattus norvegicus) were exposed to hypoxia at rest or during pre-stimulation (elevated extracellular potassium, epinephrine or norepinephrine). Hypoxia produced a relaxation or transient contraction followed by relaxation in all pre-gill vessels, except for contraction in lamprey, and vasoconstriction or tri-phasic constriction-dilation-constriction in all pulmonary vessels. Hypoxia contracted systemic vessels from all animals except shark and rat and in pre-contracted rat aortas it produced a transient contraction followed by relaxation. These results show that while the classic "systemic hypoxic vasodilation and pulmonary hypoxic vasoconstriction" may occur in the microcirculation, the hypoxic response of the vertebrate macrocirculation is quite variable. These findings also suggest that hypoxic vasoconstriction is a phylogenetically ancient response. PMID:18214862

  9. Three crocodilian genomes reveal ancestral patterns of evolution among archosaurs.

    PubMed

    Green, Richard E; Braun, Edward L; Armstrong, Joel; Earl, Dent; Nguyen, Ngan; Hickey, Glenn; Vandewege, Michael W; St John, John A; Capella-Gutiérrez, Salvador; Castoe, Todd A; Kern, Colin; Fujita, Matthew K; Opazo, Juan C; Jurka, Jerzy; Kojima, Kenji K; Caballero, Juan; Hubley, Robert M; Smit, Arian F; Platt, Roy N; Lavoie, Christine A; Ramakodi, Meganathan P; Finger, John W; Suh, Alexander; Isberg, Sally R; Miles, Lee; Chong, Amanda Y; Jaratlerdsiri, Weerachai; Gongora, Jaime; Moran, Christopher; Iriarte, Andrés; McCormack, John; Burgess, Shane C; Edwards, Scott V; Lyons, Eric; Williams, Christina; Breen, Matthew; Howard, Jason T; Gresham, Cathy R; Peterson, Daniel G; Schmitz, Jürgen; Pollock, David D; Haussler, David; Triplett, Eric W; Zhang, Guojie; Irie, Naoki; Jarvis, Erich D; Brochu, Christopher A; Schmidt, Carl J; McCarthy, Fiona M; Faircloth, Brant C; Hoffmann, Federico G; Glenn, Travis C; Gabaldón, Toni; Paten, Benedict; Ray, David A

    2014-12-12

    To provide context for the diversification of archosaurs--the group that includes crocodilians, dinosaurs, and birds--we generated draft genomes of three crocodilians: Alligator mississippiensis (the American alligator), Crocodylus porosus (the saltwater crocodile), and Gavialis gangeticus (the Indian gharial). We observed an exceptionally slow rate of genome evolution within crocodilians at all levels, including nucleotide substitutions, indels, transposable element content and movement, gene family evolution, and chromosomal synteny. When placed within the context of related taxa including birds and turtles, this suggests that the common ancestor of all of these taxa also exhibited slow genome evolution and that the comparatively rapid evolution is derived in birds. The data also provided the opportunity to analyze heterozygosity in crocodilians, which indicates a likely reduction in population size for all three taxa through the Pleistocene. Finally, these data combined with newly published bird genomes allowed us to reconstruct the partial genome of the common ancestor of archosaurs, thereby providing a tool to investigate the genetic starting material of crocodilians, birds, and dinosaurs. PMID:25504731

  10. A comparative examination of odontogenic gene expression in both toothed and toothless amniotes.

    PubMed

    Lainoff, Alexis J; Moustakas-Verho, Jacqueline E; Hu, Diane; Kallonen, Aki; Marcucio, Ralph S; Hlusko, Leslea J

    2015-05-01

    A well-known tenet of murine tooth development is that BMP4 and FGF8 antagonistically initiate odontogenesis, but whether this tenet is conserved across amniotes is largely unexplored. Moreover, changes in BMP4-signaling have previously been implicated in evolutionary tooth loss in Aves. Here we demonstrate that Bmp4, Msx1, and Msx2 expression is limited proximally in the red-eared slider turtle (Trachemys scripta) mandible at stages equivalent to those at which odontogenesis is initiated in mice, a similar finding to previously reported results in chicks. To address whether the limited domains in the turtle and the chicken indicate an evolutionary molecular parallelism, or whether the domains simply constitute an ancestral phenotype, we assessed gene expression in a toothed reptile (the American alligator, Alligator mississippiensis) and a toothed non-placental mammal (the gray short-tailed opossum, Monodelphis domestica). We demonstrate that the Bmp4 domain is limited proximally in M. domestica and that the Fgf8 domain is limited distally in A. mississippiensis just preceding odontogenesis. Additionally, we show that Msx1 and Msx2 expression patterns in these species differ from those found in mice. Our data suggest that a limited Bmp4 domain does not necessarily correlate with edentulism, and reveal that the initiation of odontogenesis in non-murine amniotes is more complex than previously imagined. Our data also suggest a partially conserved odontogenic program in T. scripta, as indicated by conserved Pitx2, Pax9, and Barx1 expression patterns and by the presence of a Shh-expressing palatal epithelium, which we hypothesize may represent potential dental rudiments based on the Testudinata fossil record. PMID:25678399

  11. A comparative examination of odontogenic gene expression in both toothed and toothless amniotes

    PubMed Central

    Lainoff, Alexis J.; Moustakas-Verho, Jacqueline E.; Hu, Diane; Kallonen, Aki; Marcucio, Ralph S.; Hlusko, Leslea J.

    2015-01-01

    A well-known tenet of murine tooth development is that BMP4 and FGF8 antagonistically initiate odontogenesis, but whether this tenet is conserved across amniotes is largely unexplored. Moreover, changes in BMP4-signaling have previously been implicated in evolutionary tooth loss in Aves. Here we demonstrate that Bmp4, Msx1, and Msx2 expression is limited proximally in the red-eared slider turtle (Trachemys scripta) mandible at stages equivalent to those at which odontogenesis is initiated in mice, a similar finding to previously reported results in chicks. To address whether the limited domains in the turtle and the chicken indicate an evolutionary molecular parallelism, or whether the domains simply constitute an ancestral phenotype, we assessed gene expression in a toothed reptile (the American alligator, Alligator mississippiensis) and a toothed non-placental mammal (the gray short-tailed opossum, Monodelphis domestica). We demonstrate that the Bmp4 domain is limited proximally in M. domestica and that the Fgf8 domain is limited distally in A. mississippiensis just preceding odontogenesis. Additionally, we show that Msx1 and Msx2 expression patterns in these species differ from those found in mice. Our data suggest that a limited Bmp4 domain does not necessarily correlate with edentulism, and reveal that the initiation of odontogenesis in non-murine amniotes is more complex than previously imagined. Our data also suggest a partially conserved odontogenic program in T. scripta, as indicated by conserved Pitx2, Pax9, and Barx1 expression patterns and by the presence of a Shh-expressing palatal epithelium, which we hypothesize may represent potential dental rudiments based on the Testudinata fossil record. PMID:25678399

  12. KSC-04PD-0203

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. A moss-covered alligator stretches out on the waters edge at a bank on the west side of NASAs Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  13. 78 FR 23286 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ... Heads of Executive Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR... include American crocodile or American alligator) Testudinidae Species Asian elephant (Elephas...

  14. KSC-04PD-0201

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. An alligator makes a splashy entrance into the water on the west side of NASAs Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  15. KSC-04PD-0050

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- An alligator is spotted sunning on the muddy bank of a canal in KSC. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  16. KSC-04PD-0049

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. -- An alligator is spotted sunning on the muddy bank of a canal in KSC. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  17. KSC-05PD-0309

    NASA Technical Reports Server (NTRS)

    2005-01-01

    KENNEDY SPACE CENTER, FLA. An alligator strolls across the ground near the Vehicle Assembly Building (in the background). Nearly 5,000 alligators can be found in canals, ponds and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  18. KSC-04PD-0200

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. An alligator slides off a bank into the water on the west side of NASAs Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles.

  19. 50 CFR 17.84 - Special rules-vertebrates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... accordance with the requirements of 50 CFR 424.11(d). If a catastrophic event were to significantly diminish... reported to either the Refuge Manager, Alligator River National Wildlife Refuge, Manteo, North Carolina... (c) (2) through (7) of this section. (9)(i) The Alligator River reintroduction site is within...

  20. 77 FR 7172 - Sequoyah National Wildlife Refuge, Sequoyah, Muskogee, and Haskell Counties, OK; Comprehensive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-10

    ... (63 FR 33693), stating that we intended to prepare a CCP and EA for Sequoyah NWR. We held a public..., prothonotary warblers, wood ducks, mallards, teal, common snipe, alligator snapping turtles, white-tailed deer... alligator snapping turtle is another species of concern on the Refuge, as the creeks, lakes, wetlands,...

  1. 7 CFR 319.37-7 - Postentry quarantine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... affecting § 319.37-7, see the List of CFR Sections Affected, which appears in the Finding Aids section of..., alligator apple, suncoya, ilama, guanabana, pond apple Anacardium— cashew Artocarpus— breadfruit, jackfruit..., genip Nephelium— rambutan, pulasan Olea— olive Persea— avocado, alligator pear Phyllanthus—...

  2. 78 FR 65352 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-31

    ... Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR 4685; January 26, 2009... Center, Sausalito, CA; PRT-101713 On November 5, 2012 (77 FR 66476), we published a notice of receipt of...) Golden parakeet (Guarouba guarouba) Chinese alligator (Alligator sinensis) Radiated tortoise...

  3. 7 CFR 319.37-7 - Postentry quarantine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... affecting § 319.37-7, see the List of CFR Sections Affected, which appears in the Finding Aids section of..., cherimoya, sweetsop, sugarapple, soursop, bullock's heart, alligator apple, suncoya, ilama, guanabana, pond... Olea— olive Persea— avocado, alligator pear Phyllanthus— otaheite-gooseberry Pistacia—...

  4. 7 CFR 319.37-7 - Postentry quarantine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... affecting § 319.37-7, see the List of CFR Sections Affected, which appears in the Finding Aids section of..., alligator apple, suncoya, ilama, guanabana, pond apple Anacardium— cashew Artocarpus— breadfruit, jackfruit..., genip Nephelium— rambutan, pulasan Olea— olive Persea— avocado, alligator pear Phyllanthus—...

  5. 50 CFR 32.37 - Louisiana.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... taking of alligator snapping turtle (see § 27.21 of this chapter). 5. We only allow fishing during..., slat traps, gar sets, nets or alligator lines is prohibited on the refuge. 5. Only outboard motors 25... while fishing. 3. We prohibit the use of trotlines, limblines, slat traps, gar sets, nets, or...

  6. 50 CFR 17.84 - Special rules-vertebrates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... accordance with the requirements of 50 CFR 424.11(d). If a catastrophic event were to significantly diminish... reported to either the Refuge Manager, Alligator River National Wildlife Refuge, Manteo, North Carolina... (c) (2) through (7) of this section. (9)(i) The Alligator River reintroduction site is within...

  7. 7 CFR 319.37-7 - Postentry quarantine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... affecting § 319.37-7, see the List of CFR Sections Affected, which appears in the Finding Aids section of..., alligator apple, suncoya, ilama, guanabana, pond apple Anacardium— cashew Artocarpus— breadfruit, jackfruit..., genip Nephelium— rambutan, pulasan Olea— olive Persea— avocado, alligator pear Phyllanthus—...

  8. 50 CFR 32.37 - Louisiana.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... into the water. 3. We prohibit commercial fishing. 4. We prohibit the taking of alligator snapping..., slat traps, gar sets, nets or alligator lines is prohibited on the refuge. 5. Only outboard motors 25... while fishing. 3. We prohibit the use of trotlines, limblines, slat traps, gar sets, nets, or...

  9. 75 FR 29253 - Proposed Flood Elevation Determinations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-25

    ..., 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 2. The tables... 925 6th Street, Del Norte, CO 81132. Washington County, Florida, and Incorporated Areas Alligator... confluence with Holmes Creek. Helms Branch At the confluence with None +78 City of Chipley, Alligator...

  10. 78 FR 33300 - Endangered and Threatened Wildlife and Plants; 12-Month Finding and Proposed Endangered Listing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    ... the ESA. On March 7, 2011, we published a 90-day finding (76 FR 12308) stating the petitioned action...; 68 FR 15100; March 28, 2003) to determine their certainty of implementation and effectiveness for... (Carcharhinus leucas), estuarine crocodiles (Crocodylus porosus) or alligators (Alligator...

  11. 7 CFR 319.37-7 - Postentry quarantine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... affecting § 319.37-7, see the List of CFR Sections Affected, which appears in the Finding Aids section of..., cherimoya, sweetsop, sugarapple, soursop, bullock's heart, alligator apple, suncoya, ilama, guanabana, pond... Olea— olive Persea— avocado, alligator pear Phyllanthus— otaheite-gooseberry Pistacia—...

  12. 50 CFR 17.84 - Special rules-vertebrates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... accordance with the requirements of 50 CFR 424.11(d). If a catastrophic event were to significantly diminish... reported to either the Refuge Manager, Alligator River National Wildlife Refuge, Manteo, North Carolina... (c) (2) through (7) of this section. (9)(i) The Alligator River reintroduction site is within...

  13. 75 FR 53328 - Proposed Information Collection; OMB Control Number 1018-0093; Federal Fish and Wildlife License...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ..., Information Collection Clearance Officer, Fish and Wildlife Service. FR Doc. 2010-21724 Filed 8-30-10; 8:45 am... a CITES Export Program (American ginseng, CITES furbearers, American Alligator)). Applicants... (Report for American Alligator CITES Export Programs). Applicants currently submit this report in...

  14. 75 FR 11808 - Injurious Wildlife Species; Listing the Boa Constrictor, Four Python Species, and Four Anaconda...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... South Florida. The Service published a notice of inquiry in the Federal Register (73 FR 5784; January 31... prey items include alligators, antelopes, dogs, deer, jackals, goats, porcupines, wild boars, pangolins..., including such large prey as deer and crocodilians (alligators are a type of crocodilian). The...

  15. Iodine-enhanced micro-CT imaging: methodological refinements for the study of the soft-tissue anatomy of post-embryonic vertebrates.

    PubMed

    Gignac, Paul M; Kley, Nathan J

    2014-05-01

    The now widespread use of non-destructive X-ray computed tomography (CT) and micro-CT (µCT) has greatly augmented our ability to comprehensively detail and quantify the internal hard-tissue anatomy of vertebrates. However, the utility of X-ray imaging for gaining similar insights into vertebrate soft-tissue anatomy has yet to be fully realized due to the naturally low X-ray absorption of non-mineralized tissues. In this study, we show how a wide diversity of soft-tissue structures within the vertebrate head-including muscles, glands, fat deposits, perichondria, dural venous sinuses, white and gray matter of the brain, as well as cranial nerves and associated ganglia-can be rapidly visualized in their natural relationships with extraordinary levels of detail using iodine-enhanced (i-e) µCT imaging. To date, Lugol's iodine solution (I2 KI) has been used as a contrast agent for µCT imaging of small invertebrates, vertebrate embryos, and certain isolated parts of larger, post-embryonic vertebrates. These previous studies have all yielded promising results, but visualization of soft tissues in smaller invertebrate and embryonic vertebrate specimens has generally been more complete than that for larger, post-embryonic vertebrates. Our research builds on these previous studies by using high-energy µCT together with more highly concentrated I2 KI solutions and longer staining times to optimize the imaging and differentiation of soft tissues within the heads of post-embryonic archosaurs (Alligator mississippiensis and Dromaius novaehollandiae). We systematically quantify the intensities of tissue staining, demonstrate the range of anatomical structures that can be visualized, and generate a partial three-dimensional reconstruction of alligator cephalic soft-tissue anatomy. PMID:24482316

  16. New resources inform study of genome size, content, and organization in nonavian reptiles

    PubMed Central

    Janes, Daniel E.; Organ, Christopher; Valenzuela, Nicole

    2008-01-01

    Genomic resources for studies of nonavian reptiles have recently improved and will reach a new level of access once the genomes of the painted turtle (Chrysemys picta) and the green anole (Anolis carolinensis) have been published. Eleven speakers gathered for a symposium on reptilian genomics and evolutionary genetics at the 2008 meeting of the Society for Integrative and Comparative Biology in San Antonio, Texas. Presentations described results of reptilian genetic studies concerning molecular evolution, chromosomal evolution, genomic architecture, population dynamics, endocrinology and endocrine disruption, and the evolution of developmental mechanisms. The presented studies took advantage of the recent generation of genetic and genomic tools and resources. Novel findings demonstrated the positive impact made by the improved availability of resources like genome annotations and bacterial artificial chromosomes (BACs). The symposium was timely and important because it provided a vehicle for the dissemination of novel findings that advance the field. Moreover, this meeting fostered the synergistic interaction of the participants as a group, which is anticipated to encourage the funding and creation of further resources such as additional BAC libraries and genomic projects. Novel data have already been collected and studies like those presented in this symposium promise to shape and improve our understanding of overall amniote evolution. Additional reptilian taxa such as the American alligator (Alligator mississippiensis), tuatara (Sphenodon punctatus), and garter snake (Thamnophis sirtalis) should be the foci of future genomic projects. We hope that the following articles in this volume will help promote these efforts by describing the conclusions and the potential that the improvement of genomic resources for nonavian reptiles can continue having in this important area of integrative and comparative biology. PMID:21669805

  17. Histological evidence for muscle insertion in extant amniote femora: implications for muscle reconstruction in fossils

    PubMed Central

    Petermann, Holger; Sander, Martin

    2013-01-01

    Since the 19th century, identification of muscle attachment sites on bones has been important for muscle reconstructions, especially in fossil tetrapods, and therefore has been the subject of numerous biological and paleontological studies. At the microscopic level, in histological thin sections, the only features that can be used reliably for identifying tendon–bone or muscle–tendon-bone interactions are Sharpey's fibers. Muscles, however, do not only attach to the bone indirectly with tendons, but also directly. Previous studies failed to provide new indicators for muscle attachment, or to address the question of whether muscles with direct attachment can be identified histologically. However, histological identification of direct muscle attachments is important because these attachments do not leave visible marks (e.g. scars and rugosities) on the bone surface. We dissected the right hind limb and mapped the muscle attachment sites on the femur of one rabbit (Oryctolagus cuniculus), one Alligator mississippiensis, and one turkey (Meleagris cuniculus). We then extracted the femur and prepared four histological thin sections for the rabbit and the turkey and five histological thin sections for the alligator. Sharpey's fibers, vascular canal orientation, and a frayed periosteal margin can be indicators for indirect but also direct muscle attachment. Sharpey's fibers can be oriented to the cutting plane of the thin section at high angles, and two Sharpey's fibers orientations can occur in one area, possibly indicating a secondary force axis. However, only about 60% of mapped muscle attachment sites could be detected in thin sections, and frequently histological features suggestive of muscle attachment occurred outside mapped sites. While these insights should improve our ability to successfully identify and reconstruct muscles in extinct species, they also show the limitations of this approach. PMID:23439026

  18. Similarity of Crocodilian and Avian Lungs Indicates Unidirectional Flow Is Ancestral for Archosaurs.

    PubMed

    Farmer, C G

    2015-12-01

    Patterns of airflow and pulmonary anatomy were studied in the American alligator (Alligator mississippiensis), the black caiman (Melanosuchus niger), the spectacled caiman (Caiman crocodilus), the dwarf crocodile (Osteolaemus tetraspis), the saltwater crocodile (Crocodylus porosus), the Nile crocodile (Crocodylus niloticus), and Morelet's crocodile (Crocodylus moreletii). In addition, anatomy was studied in the Orinoco crocodile (Crocodylus intermedius). Airflow was measured using heated thermistor flow meters and visualized by endoscopy during insufflation of aerosolized propolene glycol and glycerol. Computed tomography and gross dissection were used to visualize the anatomy. In all species studied a bird-like pattern of unidirectional flow was present, in which air flowed caudad in the cervical ventral bronchus and its branches during both lung inflation and deflation and craniad in dorsobronchi and their branches. Tubular pathways connected the secondary bronchi to each other and allowed air to flow from the dorsobronchi into the ventrobronchi. No evidence for anatomical valves was found, suggesting that aerodynamic valves cause the unidirectional flow. In vivo data from the American alligator showed that unidirectional flow is present during periods of breath-holding (apnea) and is powered by the beating heart, suggesting that this pattern of flow harnesses the heart as a pump for air. Unidirectional flow may also facilitate washout of stale gases from the lung, reducing the cost of breathing, respiratory evaporative water loss, heat loss through the heat of vaporization, and facilitating crypsis. The similarity in structure and function of the bird lung with pulmonary anatomy of this broad range of crocodilian species indicates that a similar morphology and pattern of unidirectional flow were present in the lungs of the common ancestor of crocodilians and birds. These data suggest a paradigm shift is needed in our understanding of the evolution of this

  19. Structure, innervation and response properties of integumentary sensory organs in crocodilians

    PubMed Central

    Leitch, Duncan B.; Catania, Kenneth C.

    2012-01-01

    SUMMARY Integumentary sensory organs (ISOs) are densely distributed on the jaws of crocodilians and on body scales of members of the families Crocodilidae and Gavialidae. We examined the distribution, anatomy, innervation and response properties of ISOs on the face and body of crocodilians and documented related behaviors for an alligatorid (Alligator mississippiensis) and a crocodylid (Crocodylus niloticus). Each of the ISOs (roughly 4000 in A. mississippiensis and 9000 in C. niloticus) was innervated by networks of afferents supplying multiple different mechanoreceptors. Electrophysiological recordings from the trigeminal ganglion and peripheral nerves were made to isolate single-unit receptive fields and to test possible osmoreceptive and electroreceptive functions. Multiple small (<0.1 mm2) receptive fields, often from a single ISO, were recorded from the premaxilla, the rostral dentary, the gingivae and the distal digits. These responded to a median threshold of 0.08 mN. The less densely innervated caudal margins of the jaws had larger receptive fields (>100 mm2) and higher thresholds (13.725 mN). Rapidly adapting, slowly adapting type I and slowly adapting type II responses were identified based on neuronal responses. Several rapidly adapting units responded maximally to vibrations at 20–35 Hz, consistent with reports of the ISOs' role in detecting prey-generated water surface ripples. Despite crocodilians' armored bodies, the ISOs imparted a mechanical sensitivity exceeding that of primate fingertips. We conclude that crocodilian ISOs have diverse functions, including detection of water movements, indicating when to bite based on direct contact of pursued prey, and fine tactile discrimination of items held in the jaws. PMID:23136155

  20. Structure, innervation and response properties of integumentary sensory organs in crocodilians.

    PubMed

    Leitch, Duncan B; Catania, Kenneth C

    2012-12-01

    Integumentary sensory organs (ISOs) are densely distributed on the jaws of crocodilians and on body scales of members of the families Crocodilidae and Gavialidae. We examined the distribution, anatomy, innervation and response properties of ISOs on the face and body of crocodilians and documented related behaviors for an alligatorid (Alligator mississippiensis) and a crocodylid (Crocodylus niloticus). Each of the ISOs (roughly 4000 in A. mississippiensis and 9000 in C. niloticus) was innervated by networks of afferents supplying multiple different mechanoreceptors. Electrophysiological recordings from the trigeminal ganglion and peripheral nerves were made to isolate single-unit receptive fields and to test possible osmoreceptive and electroreceptive functions. Multiple small (<0.1 mm(2)) receptive fields, often from a single ISO, were recorded from the premaxilla, the rostral dentary, the gingivae and the distal digits. These responded to a median threshold of 0.08 mN. The less densely innervated caudal margins of the jaws had larger receptive fields (>100 mm(2)) and higher thresholds (13.725 mN). Rapidly adapting, slowly adapting type I and slowly adapting type II responses were identified based on neuronal responses. Several rapidly adapting units responded maximally to vibrations at 20-35 Hz, consistent with reports of the ISOs' role in detecting prey-generated water surface ripples. Despite crocodilians' armored bodies, the ISOs imparted a mechanical sensitivity exceeding that of primate fingertips. We conclude that crocodilian ISOs have diverse functions, including detection of water movements, indicating when to bite based on direct contact of pursued prey, and fine tactile discrimination of items held in the jaws. PMID:23136155

  1. Estimating cranial musculoskeletal constraints in theropod dinosaurs

    PubMed Central

    Lautenschlager, Stephan

    2015-01-01

    Many inferences on the biology, behaviour and ecology of extinct vertebrates are based on the reconstruction of the musculature and rely considerably on its accuracy. Although the advent of digital reconstruction techniques has facilitated the creation and testing of musculoskeletal hypotheses in recent years, muscle strain capabilities have rarely been considered. Here, a digital modelling approach using the freely available visualization and animation software Blender is applied to estimate cranial muscle length changes and optimal and maximal possible gape in different theropod dinosaurs. Models of living archosaur taxa (Alligator mississippiensis, Buteo buteo) were used in an extant phylogenetically bracketed framework to validate the method. Results of this study demonstrate that Tyrannosaurus rex, Allosaurus fragilis and Erlikosaurus andrewsi show distinct differences in the recruitment of the jaw adductor musculature and resulting gape, confirming previous dietary and ecological assumptions. While the carnivorous taxa T. rex and Allo. fragilis were capable of a wide gape and sustained muscle force, the herbivorous therizinosaurian E. andrewsi was constrained to small gape angles. PMID:26716007

  2. Estimating cranial musculoskeletal constraints in theropod dinosaurs.

    PubMed

    Lautenschlager, Stephan

    2015-11-01

    Many inferences on the biology, behaviour and ecology of extinct vertebrates are based on the reconstruction of the musculature and rely considerably on its accuracy. Although the advent of digital reconstruction techniques has facilitated the creation and testing of musculoskeletal hypotheses in recent years, muscle strain capabilities have rarely been considered. Here, a digital modelling approach using the freely available visualization and animation software Blender is applied to estimate cranial muscle length changes and optimal and maximal possible gape in different theropod dinosaurs. Models of living archosaur taxa (Alligator mississippiensis, Buteo buteo) were used in an extant phylogenetically bracketed framework to validate the method. Results of this study demonstrate that Tyrannosaurus rex, Allosaurus fragilis and Erlikosaurus andrewsi show distinct differences in the recruitment of the jaw adductor musculature and resulting gape, confirming previous dietary and ecological assumptions. While the carnivorous taxa T. rex and Allo. fragilis were capable of a wide gape and sustained muscle force, the herbivorous therizinosaurian E. andrewsi was constrained to small gape angles. PMID:26716007

  3. KSC Wildlife Show

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This video highlights footage of the many forms of animal and plant life that inhabit the environs surrounding KSC. Shown are birds, alligators, butterflies, and plants as they react to shuttle launches and other activities eminating from KSC.

  4. 33 CFR 165.729 - Jacksonville Harbor, Florida-security zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... regulations governing security zones contained in 33 CFR 165.33 apply. (d) The Captain of the Port... from the eastern end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island...

  5. 36 CFR 7.45 - Everglades National Park.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 CFR 1.5, the taking, possession, or disturbance of any fresh or saltwater aquatic life is...; Cuthbert, Henry, Little Henry, Seven Palm, Middle, Monroe, Long, and the Lungs Lakes; Alligator Creek...

  6. 33 CFR 165.729 - Jacksonville Harbor, Florida-security zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... regulations governing security zones contained in 33 CFR 165.33 apply. (d) The Captain of the Port... from the eastern end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island...

  7. 36 CFR 7.45 - Everglades National Park.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 CFR 1.5, the taking, possession, or disturbance of any fresh or saltwater aquatic life is...; Cuthbert, Henry, Little Henry, Seven Palm, Middle, Monroe, Long, and the Lungs Lakes; Alligator Creek...

  8. 33 CFR 165.729 - Jacksonville Harbor, Florida-security zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... regulations governing security zones contained in 33 CFR 165.33 apply. (d) The Captain of the Port... from the eastern end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island...

  9. 33 CFR 165.728 - Jacksonville, Florida-safety zones.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... zones contained in 33 CFR 165.23 apply. (d) The Captain of the Port Jacksonville, Florida will activate... end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island Terminal,...

  10. 33 CFR 165.728 - Jacksonville, Florida-safety zones.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... zones contained in 33 CFR 165.23 apply. (d) The Captain of the Port Jacksonville, Florida will activate... end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island Terminal,...

  11. 111. Doughton Park Recreation Area. View of parkway with the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    111. Doughton Park Recreation Area. View of parkway with the road crossing alligator back. Facing southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  12. 77 FR 15383 - Endangered Species; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR 4685; January 26, 2009... Alligatoridae (does not include American alligator) Boidae (does not include Mona boa or Puerto Rican...

  13. 36 CFR 7.45 - Everglades National Park.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 CFR 1.5, the taking, possession, or disturbance of any fresh or saltwater aquatic life is...; Cuthbert, Henry, Little Henry, Seven Palm, Middle, Monroe, Long, and the Lungs Lakes; Alligator Creek...

  14. 33 CFR 165.728 - Jacksonville, Florida-safety zones.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... zones contained in 33 CFR 165.23 apply. (d) The Captain of the Port Jacksonville, Florida will activate... end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island Terminal,...

  15. 114. Doughton Park Recreation Area. View of Laurel Spring Valley ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    114. Doughton Park Recreation Area. View of Laurel Spring Valley in distance, alligator back, and overlook in foreground. Looking west. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  16. 29 CFR 1926.1501 - Cranes and derricks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Transportation rules contained in 49 CFR Parts 177 and 393 concerning such vehicular transportation are... large alligator clips or other similar protection to attach the ground cable to the load....

  17. 50 CFR 13.12 - General information requirements on applications for permits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... consistent with 40 CFR 1506.5 and Departmental procedures at 516 DM 6, Appendix 1.3A. (b) Additional... plant permits: Similarity of appearance 17.52 General for wildlife 17.32 American alligator-buyer...

  18. 33 CFR 165.728 - Jacksonville, Florida-safety zones.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... zones contained in 33 CFR 165.23 apply. (d) The Captain of the Port Jacksonville, Florida will activate... end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island Terminal,...

  19. 29 CFR 1926.1501 - Cranes and derricks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Transportation rules contained in 49 CFR Parts 177 and 393 concerning such vehicular transportation are... large alligator clips or other similar protection to attach the ground cable to the load....

  20. 50 CFR 32.52 - North Carolina.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... regulations (50 CFR 27.42 and specific regulations in part 32). We prohibit hunting, taking, and attempting to... listed in alphabetical order with applicable refuge-specific regulations. Alligator River...

  1. 29 CFR 1926.550 - Cranes and derricks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contained in 49 CFR Parts 177 and 393 concerning such vehicular transportation are considered applicable... alligator clips or other similar protection to attach the ground cable to the load. (c) Combustible...

  2. 50 CFR 13.12 - General information requirements on applications for permits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... consistent with 40 CFR 1506.5 and Departmental procedures at 516 DM 6, Appendix 1.3A. (b) Additional... plant permits: Similarity of appearance 17.52 General for wildlife 17.32 American alligator-buyer...

  3. 50 CFR 13.12 - General information requirements on applications for permits.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... consistent with 40 CFR 1506.5 and Departmental procedures at 516 DM 6, Appendix 1.3A. (b) Additional... plant permits: Similarity of appearance 17.52 General for wildlife 17.32 American alligator-buyer...

  4. KSC-03PD-0777

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. - A large alligator claims this stretch of water at Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the Merritt Island National Wildlife Refuge, which shares a boundary with the Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, plus a variety of insects.

  5. KSC-03PD-0954

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. -- This alligator strolls the bank alongside the Tow Road on Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, plus a variety of insects.

  6. 115. Doughton Park Recreation Area. View of roadway alignment around ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    115. Doughton Park Recreation Area. View of roadway alignment around alligator back and parking overlook in foreground. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  7. 33 CFR 165.728 - Jacksonville, Florida-safety zones.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... zones contained in 33 CFR 165.23 apply. (d) The Captain of the Port Jacksonville, Florida will activate... end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island Terminal,...

  8. 33 CFR 165.729 - Jacksonville Harbor, Florida-security zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... regulations governing security zones contained in 33 CFR 165.33 apply. (d) The Captain of the Port... from the eastern end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island...

  9. KSC-03PD-0953

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. - A very long alligator strolls the bank alongside the Tow Road on Kennedy Space Center. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center and the surrounding Merritt Island National Wildlife Refuge. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Wildlife Refuge encompasses 92,000 acres that are a habitat for more than 331 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, plus a variety of insects.

  10. 50 CFR 32.52 - North Carolina.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... regulations (50 CFR 27.42 and specific regulations in part 32). We prohibit hunting, taking, and attempting to... listed in alphabetical order with applicable refuge-specific regulations. Alligator River...

  11. 33 CFR 165.729 - Jacksonville Harbor, Florida-security zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... regulations governing security zones contained in 33 CFR 165.33 apply. (d) The Captain of the Port... from the eastern end of Transit Shed #2 to the east shore of Alligator Creek at Blount Island...

  12. 50 CFR 13.12 - General information requirements on applications for permits.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... consistent with 40 CFR 1506.5 and Departmental procedures at 516 DM 6, Appendix 1.3A. (b) Additional... plant permits: Similarity of appearance 17.52 General for wildlife 17.32 American alligator-buyer...

  13. 36 CFR 7.45 - Everglades National Park.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 CFR 1.5, the taking, possession, or disturbance of any fresh or saltwater aquatic life is...; Cuthbert, Henry, Little Henry, Seven Palm, Middle, Monroe, Long, and the Lungs Lakes; Alligator Creek...

  14. Crafty Corner.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Contains three projects that relate to plants and animals of wetlands. Includes instructions and patterns for making cattails, pitcher plants (that really catch flies), and stand-up wetland animals such as insects, birds, crabs, and alligators. (TW)

  15. 50 CFR 32.52 - North Carolina.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... regulations (50 CFR 27.42 and specific regulations in part 32). We prohibit hunting, taking, and attempting to... listed in alphabetical order with applicable refuge-specific regulations. Alligator River...

  16. 50 CFR 32.52 - North Carolina.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) firearms in accordance with refuge regulations (50 CFR 27.42 and specific regulations in part 32). We... listed in alphabetical order with applicable refuge-specific regulations. Alligator River...

  17. 36 CFR 7.45 - Everglades National Park.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 CFR 1.5, the taking, possession, or disturbance of any fresh or saltwater aquatic life is...; Cuthbert, Henry, Little Henry, Seven Palm, Middle, Monroe, Long, and the Lungs Lakes; Alligator Creek...

  18. EMERGING ISSUES RELATED TO ENDOCRINE DISRUPTING CHEMICALS AND ENVIRONMENTAL ANDROGENS AND ANTIANDROGENS

    EPA Science Inventory

    Wildlife populations from contaminated ecosystems display a variety of reproductive alterations including cryptorchidism in the Florida panther, small baculum in young male otters, small penises in alligators, sex reversal in fish, and altered social behavior in birds. In some c...

  19. CHARACTERIZATION OF ENDOCRINE-DISRUPTION AND CLINICAL MANIFESTATIONS IN LARGE-MOUTH BASS FROM FLORIDA LAKES

    EPA Science Inventory

    Previous efforts from this laboratory, have documented altered endocrine function and sexual differentiation for alligators and turtles from Lake Apopka in Central Florida. This lake has been exposed to a variety of contaminants which are potentially endocrine-disrupting. Therefo...

  20. Cytochrome P4501A immunoassay in freshwater turtles and exposure to PCBs and environmental pollutants

    SciTech Connect

    Yawetz, A.; Benedek-Segal, M.; Woodin, B.

    1997-09-01

    This is the result of a comparative study of cytochrome P4501A (CYP1A) induction in liver microsomes from three species of freshwater turtles. CYP1A induction in turtle hepatic microsomes was compared to CYP1A induction in microsomes from the alligator. Alligator mississippiensis. Treatment of two species of freshwater turtles with four consecutive intraperitoneal injections of 100 mg/kg Aroclor 1254 caused a four- to five-fold increase in P4501A in hepatic microsomes of Chrysemys picta picta and Chrysemys picta elegans. The same treatment administered to another freshwater turtle, Mauremys caspica rivulata, resulted in a very low but significant (p < 0.01) induction of P4501A in hepatic microsomes. Specimens of M. caspica rivulata collected from an organic waste oxidation pond near the petrochemical industry area of the city of Ashdod exhibited normal levels of total hepatic microsomal cytochrome P450 but no detectable level of induction of cytochrome P4501A. The lack of P4501A1 induction could have resulted from two possible reasons. The first possibility is that the turtles were not exposed to residues of petrochemical waste in the pond. More likely, the apparent lack of induction resulted from the low response to CYP1A inducers found in this species. Induction of cytochrome P4501A was evaluated immunohistochemically in liver tissue of C. picta picta pretreated with Aroclor 1254 or 3,3{prime},4,4{prime}-tetrachlorobiphenyl. The most intensive staining was exhibited by sections of liver from a 3,3{prime},4,4{prime}-tetrachlorobiphenyl-treated turtle. Staining of P4501A in liver sections from Aroclor 1254-treated turtles was relatively moderate. In induced turtles, staining of the hepatocytes concentrated near the cell membranes and nuclear membranes, but stained granules were observed throughout the cytoplasm. The presence of inducible CYP1A enzymes in turtles is of importance from an evolutionary point of view and has potential ecological relevance.

  1. Check-list of the pentastomid parasites crocodilians and freshwater chelonians.

    PubMed

    Junker, K; Boomker, J

    2006-03-01

    Based on published records and own data a summary is given of the geographical distribution of the currently known species of pentastomid parasites infecting crocodiles and alligators, as well as freshwater chelonians. A brief generic diagnosis is provided for each genus. Fourteen out of the currently 23 living crocodilian species have been recorded as being host to one or more pentastomes. Out of the 32 pentastome species six are considered species inquirendae. Presently, six genera of crocodilian pentastomes, Agema, Alofia, Leiperia, Sebekia, Selfia and Subtriquetra are recognized. African crocodiles harbour eight pentastome species, six of which have been recorded from the Nile crocodile, Crocodylus niloticus. Three species belong to the genus Sebekia, Alofia being represented by two and Leiperia by only one species. Two species, Alofia parva and Agema silvae-palustris, occur in the dwarf crocodile, Osteolaemus tetraspis, and the slender-snouted crocodile, Crocodylus cataphractus, exclusively, but a single Sebekia species is shared with the Nile crocodile. The genus Agema is endemic to the African region. Infective stages of the pentastome Subtriquetra rileyi, thought to utilize Nile crocodiles as final hosts, have been recovered only from fishes. The largest number of pentastome species is found in the Australasian region. Of these, the Indo-Pacific crocodile, Crocodylus porosus, harbours seven, representing the genera Alofia, Sebekia, Leiperia and Selfia. Selfia is exclusive to the latter host. The genus Subtriquetra has been reported from "Indian crocodiles", a term possibly referring to either Crocodylus palustris, Crocodylus porosus or Gavialis gangeticus. Ten species of pentastomes parasitizing the crocodilian genera Alligator, Caiman, Crocodylus and Melanosuchus have been recorded from the Neotropical region including the southern states of the North American continent. The two most wide-spread pentastome genera, Alofia and Sebekia, have been recorded

  2. Fate of Airborne Contaminants in Okefenokee National Wildlife Refuge

    USGS Publications Warehouse

    Winger, P.V.; Lasier, P.J.

    1997-01-01

    Designation of Okefenokee National Wildlife Refuge as a Class I Air Quality Area (given the highest level of protection possible from air pollutants under the Clean Air Act Amendments of 1977) affords mandatory protection of the Refuge's airshed through the permit-review process for planned developments. Rainfall is the major source of water to the swamp, and potential impacts from developments to the airshed are high. To meet management needs for baseline information, chemical contributions from atmospheric deposition and partitioning of anions and cations, with emphasis on mercury and lead, in the various matrices of the Swamp were determined between July 1993 and April 1995. Chemistry of rainfall was determined on an event basis from one site located at Refuge Headquarters. Field samples of surface water, pore water, floc and sediment were collected from four locations on the Refuge: Chesser Prairie, Chase Prairie, Durden Prairie, and the Narrows. A sediment core sample was collected from the Refuge interior at Bluff Lake for aging of mercury deposition. Rainfall was acidic (pH 4.8) with sulfate concentrations averaging 1.2 mg/L and nitrate averaging 0.8 mg/L. Lead in rainfall averaged 1 ?g/L and total and methylmercury concentrations were 11.7 ng/L and 0.025 ng/L, respectively. The drought of 1993 followed by heavy rains during the fall and winter caused a temporary alteration in the cycling and availability of trace-elements within the different matrices of the Swamp. Surface water was acidic (pH 3.8 to 4.1), dilute (specific conductance 35-60 ?S/cm), and highly organic (DOC 35-50 mg/L). Sediment and floc were also highly organic (>90%). Total mercury averaged 3.6 ng/L in surface water, 9.0 ng/L in pore water and about 170 ng/g in floc and sediments. Mercury bioaccumulated in the biota of the Refuge: fish fillets (Centrarchus macropterus, Esox niger, Lepomus gulosus and Amia calva) had >2 ?g/g dry weight, alligators (Alligator mississippiensis) >4 ?g/g dry

  3. Small sample sizes in the study of ontogenetic allometry; implications for palaeobiology

    PubMed Central

    Vavrek, Matthew J.

    2015-01-01

    Quantitative morphometric analyses, particularly ontogenetic allometry, are common methods used in quantifying shape, and changes therein, in both extinct and extant organisms. Due to incompleteness and the potential for restricted sample sizes in the fossil record, palaeobiological analyses of allometry may encounter higher rates of error. Differences in sample size between fossil and extant studies and any resulting effects on allometric analyses have not been thoroughly investigated, and a logical lower threshold to sample size is not clear. Here we show that studies based on fossil datasets have smaller sample sizes than those based on extant taxa. A similar pattern between vertebrates and invertebrates indicates this is not a problem unique to either group, but common to both. We investigate the relationship between sample size, ontogenetic allometric relationship and statistical power using an empirical dataset of skull measurements of modern Alligator mississippiensis. Across a variety of subsampling techniques, used to simulate different taphonomic and/or sampling effects, smaller sample sizes gave less reliable and more variable results, often with the result that allometric relationships will go undetected due to Type II error (failure to reject the null hypothesis). This may result in a false impression of fewer instances of positive/negative allometric growth in fossils compared to living organisms. These limitations are not restricted to fossil data and are equally applicable to allometric analyses of rare extant taxa. No mathematically derived minimum sample size for ontogenetic allometric studies is found; rather results of isometry (but not necessarily allometry) should not be viewed with confidence at small sample sizes. PMID:25780770

  4. Tooth counts through growth in diapsid reptiles: implications for interpreting individual and size-related variation in the fossil record.

    PubMed

    Brown, Caleb Marshall; VanBuren, Collin S; Larson, Derek W; Brink, Kirstin S; Campione, Nicolás E; Vavrek, Matthew J; Evans, David C

    2015-04-01

    Tooth counts are commonly recorded in fossil diapsid reptiles and have been used for taxonomic and phylogenetic purposes under the assumption that differences in the number of teeth are largely explained by interspecific variation. Although phylogeny is almost certainly one of the greatest factors influencing tooth count, the relative role of intraspecific variation is difficult, and often impossible, to test in the fossil record given the sample sizes available to palaeontologists and, as such, is best investigated using extant models. Intraspecific variation (largely manifested as size-related or ontogenetic variation) in tooth counts has been examined in extant squamates (lizards and snakes) but is poorly understood in archosaurs (crocodylians and dinosaurs). Here, we document tooth count variation in two species of extant crocodylians (Alligator mississippiensis and Crocodylus porosus) as well as a large varanid lizard (Varanus komodoensis). We test the hypothesis that variation in tooth count is driven primarily by growth and thus predict significant correlations between tooth count and size, as well as differences in the frequency of deviation from the modal tooth count in the premaxilla, maxilla, and dentary. In addition to tooth counts, we also document tooth allometry in each species and compare these results with tooth count change through growth. Results reveal no correlation of tooth count with size in any element of any species examined here, with the exception of the premaxilla of C. porosus, which shows the loss of one tooth position. Based on the taxa examined here, we reject the hypothesis, as it is evident that variation in tooth count is not always significantly correlated with growth. However, growth trajectories of smaller reptilian taxa show increases in tooth counts and, although current samples are small, suggest potential correlates between tooth count trajectories and adult size. Nevertheless, interspecific variation in growth patterns

  5. First Record of Eocene Bony Fishes and Crocodyliforms from Canada’s Western Arctic

    PubMed Central

    Eberle, Jaelyn J.; Gottfried, Michael D.; Hutchison, J. Howard; Brochu, Christopher A.

    2014-01-01

    time between the two extant alligatorid lineages Alligator mississippiensis and A. sinensis, and high-latitude dispersal across Beringia. PMID:24788829

  6. Multidisciplinary study of radionuclides and heavy-metal concentrations in wildlife on phosphate-mined and reclaimed lands. Final report

    SciTech Connect

    Pritchard, P.C.H.; Bloodwell, J.M.

    1986-11-01

    The phosphate-rich mineral deposits of central Florida tend to exhibit background radiation levels that are elevated due to the uranium and its decay products found in association with the ore. The report documents radioactivity levels in two groups of animals that had heretofore not been examined by other investigators -- aquatic reptiles (American alligators, softshell turtles, and Florida cooter turtles) and terrestrial mammals (armadillos), based on the criterion that these species have significant proportions of their mass comprised of bony tissue likely to show elevated concentrations of radium. The alligator bones contained only low concentrations of radium, and there were no significant differences between alligators collected from mined, mineralized-unmined, or unmineralized land. Whether the levels of radium in the bones of the turtles represents a hazard to the health of these long-lived animals or to humans who may consume their flesh is unclear.

  7. KSC-04PD-1250

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. Above, herons, a roseate spoonbill and other species of water birds gather in a canal near KSC, which shares a boundary with the Merritt Island National Wildlife Refuge. Below is an alligator. Nearly 5,000 alligators can be found in canals, ponds, and waterways throughout the Center. The marshes and open water of the refuge also 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.

  8. Flexible Dermal Armor in Nature

    NASA Astrophysics Data System (ADS)

    Yang, Wen; Chen, Irene H.; Mckittrick, Joanna; Meyers, Marc A.

    2012-04-01

    Many animals possess dermal armor, which acts primarily as protection against predators. We illustrate this through examples from both our research and the literature: alligator, fish (alligator gar, arapaima, and Senegal bichir), armadillo, leatherback turtle, and a lizard, the Gila monster. The dermal armor in these animals is flexible and has a hierarchical structure with collagen fibers joining mineralized units (scales, tiles, or plates). This combination significantly increases the strength and flexibility in comparison with a simple monolithic mineral composite or rigid dermal armor. This dermal armor is being studied for future bioinspired armor applications providing increased mobility.

  9. 78 FR 2687 - National Register of Historic Places; Notification of Pending Nominations and Related Actions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-14

    ... County Black, L.A., Rice Milling Association Inc. Office, 508 S. Monroe St., DeWitt, 12001229 Columbia... Orleans, 12001241 MISSOURI Buchanan County Ryan Block, (St. Joseph MPS (AD)) 1137-1141 Frederick Ave., Saint Joseph, 12001242 St. Louis Independent city Alligator Oil Clothing Company Building,...

  10. Systena silvestrii bechyne (Coleoptera:Chrysomelidae):Redescripton,new distribution and adult host records

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The flea beetle Systena silvestrii Bechyné 1957, was studied in context with the evaluation of natural enemies of the alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae). The female is described and the holotype male is redescribed adding new diagnostic characters: mouth...

  11. 50 CFR 13.11 - Application procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (native furbearers and alligators—excluding live animals) 50 CFR 23 100 50 CITES Master File (includes... (American Ginseng, Certain Furbearers, and American Alligator) 50 CFR 23 (1) (1) Import/Export License 50... permits (50 CFR 21.22) by writing to: Bird Banding Laboratory, USGS Patuxent Wildlife Research...

  12. 76 FR 35111 - Final Flood Elevation Determinations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-16

    ... Executive Order 12866 of September 30, 1993, Regulatory Planning and Review, 58 FR 51735. Executive Order....C. 4001 et seq.; Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR... Docket No.: FEMA-B-1097 Alligator Creek At the upstream side of +76 Unincorporated Areas of County...

  13. 36 CFR 7.86 - Big Cypress National Preserve.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... at the time the land was acquired for preserve purposes (See 36 CFR 2.60). (2) Such permit may be... permittee. (5) Annual fees based on Departmental regulations (43 CFR 4125.1-1 (m)) will be charged for all... Alligator Alley; and the two marked loop trails are closed to the use of all motorized vehicles, except...

  14. 50 CFR 13.11 - Application procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (native furbearers and alligators—excluding live animals) 50 CFR 23 100 50 CITES Master File (includes... (American Ginseng, Certain Furbearers, and American Alligator) 50 CFR 23 (1) (1) Import/Export License 50... permits (50 CFR 21.22) by writing to: Bird Banding Laboratory, USGS Patuxent Wildlife Research...

  15. Science: What Reptiles Are and Aren't

    ERIC Educational Resources Information Center

    Axelrod, Gerry S.

    1978-01-01

    Many children have an enormous fascination for reptiles of all kinds--snakes, turtles, tortoises, crocodiles, alligators and lizards. Whatever the reason for their interest, you can channel the enthusiasm of reptile fans and build the interest of curious students with a few simple activities, e.g., getting acquainted with reptile characteristics…

  16. 50 CFR 13.11 - Application procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (native furbearers and alligators—excluding live animals) 50 CFR 23 100 50 CITES Master File (includes... (American Ginseng, Certain Furbearers, and American Alligator) 50 CFR 23 (1) (1) Import/Export License 50... permits (50 CFR 21.22) by writing to: Bird Banding Laboratory, USGS Patuxent Wildlife Research...

  17. 75 FR 28643 - Pine Island, Matlacha Pass, Island Bay, and Caloosahatchee National Wildlife Refuges, Lee and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ... Register on June 27, 2007 (72 FR 35254), and extended the comment period in a notice in the Federal Register on April 2, 2008 (73 FR 17991). For more about the refuges, their purposes, and our CCP process... ridley sea turtle, gopher tortoise, American alligator, American crocodile, eastern indigo snake,...

  18. 36 CFR 7.86 - Big Cypress National Preserve.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... at the time the land was acquired for preserve purposes (See 36 CFR 2.60). (2) Such permit may be... permittee. (5) Annual fees based on Departmental regulations (43 CFR 4125.1-1 (m)) will be charged for all... Alligator Alley; and the two marked loop trails are closed to the use of all motorized vehicles, except...

  19. 36 CFR 7.86 - Big Cypress National Preserve.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... at the time the land was acquired for preserve purposes (See 36 CFR 2.60). (2) Such permit may be... permittee. (5) Annual fees based on Departmental regulations (43 CFR 4125.1-1 (m)) will be charged for all... Alligator Alley; and the two marked loop trails are closed to the use of all motorized vehicles, except...

  20. 36 CFR 7.86 - Big Cypress National Preserve.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... at the time the land was acquired for preserve purposes (See 36 CFR 2.60). (2) Such permit may be... permittee. (5) Annual fees based on Departmental regulations (43 CFR 4125.1-1 (m)) will be charged for all... Alligator Alley; and the two marked loop trails are closed to the use of all motorized vehicles, except...

  1. 50 CFR 13.11 - Application procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (native furbearers and alligators—excluding live animals) 50 CFR 23 100 50 CITES Master File (includes... (American Ginseng, Certain Furbearers, and American Alligator) 50 CFR 23 (1) (1) Import/Export License 50... permits (50 CFR 21.22) by writing to: Bird Banding Laboratory, USGS Patuxent Wildlife Research...

  2. The Development of Afterlife Beliefs in Religiously and Secularly Schooled Children

    ERIC Educational Resources Information Center

    Bering, Jesse M.; Blasi, Carlos Hernandez; Bjorklund, David F.

    2005-01-01

    Children aged from 4;10 to 12;9 attending either a Catholic school or a public, secular school in an eastern Spanish city observed a puppet show in which a mouse was eaten by an alligator. Children were then asked questions about the dead mouse's biological and psychological functioning. The pattern of results generally replicated that obtained…

  3. Pace's Maxims for Homegrown Library Projects. Coming Full Circle

    ERIC Educational Resources Information Center

    Pace, Andrew K.

    2005-01-01

    This article discusses six maxims by which to run library automation. The following maxims are discussed: (1) Solve only known problems; (2) Avoid changing data to fix display problems; (3) Aut viam inveniam aut faciam; (4) If you cannot make it yourself, buy something; (5) Kill the alligator closest to the boat; and (6) Just because yours is…

  4. 36 CFR 7.86 - Big Cypress National Preserve.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... at the time the land was acquired for preserve purposes (See 36 CFR 2.60). (2) Such permit may be... permittee. (5) Annual fees based on Departmental regulations (43 CFR 4125.1-1 (m)) will be charged for all... Alligator Alley; and the two marked loop trails are closed to the use of all motorized vehicles, except...

  5. 50 CFR 13.11 - Application procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Export (native furbearers and alligators—excluding live animals) 50 CFR 23 100 50 CITES Master File... Ginseng, Certain Furbearers, and American Alligator) 50 CFR 23 No fee Import/Export License 50 CFR 14 100... permits (50 CFR 21.22) by writing to: Bird Banding Laboratory, USGS Patuxent Wildlife Research...

  6. Hormonal control of metabolic substrate use by birds and reptiles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The differential use of metabolic substrates by birds is not well understood. Therefore, to clarify which substrates are preferentially utilized, studies were conducted on birds with divergent dietary habits and on a close non-avian relative of birds, alligators. Fasting plasma substrate and hormone...

  7. Energy production per circulatory cycle: a constant in resting land vertebrates?

    PubMed

    Coulson, R A; Herbert, J D

    1984-01-01

    Correcting for differences in blood flow, resting alligators, caimans, lizards, turtles, rats and dogs deaminated amino acids at the same rate. Each produced about 21 calories/kg during one complete circulatory revolution, irrespective of body temperature, size or species. Uniform O2 and substrate A-V differences are responsible for the phenomenon. PMID:6148175

  8. Into the Curriculum: Reading/Language Arts/Art: Using Amelia Bedelia Books to Teach Figurative and Literal Meanings [and] Reading/Language Arts/Mathematics: Create an Internet Pizza Cafe that Serves Pizza, Poetry, Technology, and More! [and] Reading/Language Arts: Finding Secret Words: Beginning Dictionary Skills [and] Science: What Big Teeth You Have! Alligators All Around [and] Science: Rube Goldberg and Simple Machines [and] Social Studies: Folklore--An Integrated Unit.

    ERIC Educational Resources Information Center

    Wood, Eve; Maggi, Barbara Hall; Napier, Marion; Troisi, Andrea; Heiser, Pam; Rinehart, Sharon

    1998-01-01

    Provides six fully developed library media activities that are designed for use with specific curriculum units in reading and language arts, art, mathematics, science, and social studies. Library media skills, objectives, grade levels, instructional roles, evaluation, and follow-up are described for each activity. (LRW)

  9. A Research on the Association of Pavement Surface Damages Using Data Mining

    NASA Astrophysics Data System (ADS)

    Hung, Ching-Tsung; Chang, Jia-Ray; Chen, Jian-Da; Chou, Chien-Cheng; Chen, Shih-Huang

    The association of pavement surface damages used to rely on the judgments of the experts. However, with the accumulation of data in the pavement surface maintenance database and the improvement of Data Mining, there are more and more methods available to explore the association of pavement surface damages. This research adopts Apriori algorithm to conduct association analysis on pavement surface damages. From the experience of experts, it has been believed that the association of road damages is complicated. However, through case studies, it has been found that pavement surface damages are caused among longitudinal cracking, alligator cracking and pen-holes, and they are unidirectional influence. In addition, with the help of association rules, it has been learned that, in pavement surface preventative maintenance, the top priority should be the repair of longitudinal cracking and alligator cracking, which can greatly reduce the occurrence of pen-holes and the risk of state compensations.

  10. Large Scale Discovery and De Novo-Assisted Sequencing of Cationic Antimicrobial Peptides (CAMPs) by Microparticle Capture and Electron-Transfer Dissociation (ETD) Mass Spectrometry.

    PubMed

    Juba, Melanie L; Russo, Paul S; Devine, Megan; Barksdale, Stephanie; Rodriguez, Carlos; Vliet, Kent A; Schnur, Joel M; van Hoek, Monique L; Bishop, Barney M

    2015-10-01

    The identification and sequencing of novel cationic antimicrobial peptides (CAMPs) have proven challenging due to the limitations associated with traditional proteomics methods and difficulties sequencing peptides present in complex biomolecular mixtures. We present here a process for large-scale identification and de novo-assisted sequencing of newly discovered CAMPs using microparticle capture followed by tandem mass spectrometry equipped with electron-transfer dissociation (ETD). This process was initially evaluated and verified using known CAMPs with varying physicochemical properties. The effective parameters were then applied in the analysis of a complex mixture of peptides harvested from American alligator plasma using custom-made (Bioprospector) functionalized hydrogel particles. Here, we report the successful sequencing process for CAMPs that has led to the identification of 340 unique peptides and the discovery of five novel CAMPs from American alligator plasma. PMID:26327436

  11. L-Lake wildlife: L Lake/Steel Creek Biological Monitoring Program, January 1986--December 1987

    SciTech Connect

    Patterson, K.K.; Giffin, M.A.

    1988-03-01

    Reptile and amphibian populations of L-Lake were assessed in monthly or quarterly sampling programs. Both the number of individuals and the number of species collected decreased from 1986 to 1987. The greatest difference between years occurred with amphibians. No new species were collected, less than 50% of the species collected in 1986 were collected in 1987, and only one-third as many individuals were collected. Lizard and snake populations appear unaffected by L-Lake or reactor operations. Turtles appeared to be less abundant in 1987 than in 1986. This may be due to a lack of suitable cover and food sources. With the development of macrophyte beds, the turtle populations should increase. Observations of alligators were more numerous in 1987 than 1986. Alligators successfully inhabit Par Pond, another cooling reservoir on the Savannah River Plant, and a resident population will probably become established in L-Lake.

  12. Snakes in the wrong places: Gordon Rodda’s career in invasive species research

    USGS Publications Warehouse

    Wilson, Jim

    2012-01-01

    When USGS research zoologist Gordon G. Rodda was a graduate student at Cornell University studying behavioral biology of alligators —or later, completing a post-doc at the Smithsonian Institute studying the social behavior of green iguanas in Venezuela or following that, as a statistics and sociobiology instructor at the University of Tennessee—he did not foresee that his professional future was in snakes. Lots of snakes, and in places they don’t belong.

  13. Cartilaginous Epiphyses in Extant Archosaurs and Their Implications for Reconstructing Limb Function in Dinosaurs

    PubMed Central

    Holliday, Casey M.; Ridgely, Ryan C.; Sedlmayr, Jayc C.; Witmer, Lawrence M.

    2010-01-01

    Extinct archosaurs, including many non-avian dinosaurs, exhibit relatively simply shaped condylar regions in their appendicular bones, suggesting potentially large amounts of unpreserved epiphyseal (articular) cartilage. This “lost anatomy” is often underappreciated such that the ends of bones are typically considered to be the joint surfaces, potentially having a major impact on functional interpretation. Extant alligators and birds were used to establish an objective basis for inferences about cartilaginous articular structures in such extinct archosaur clades as non-avian dinosaurs. Limb elements of alligators, ostriches, and other birds were dissected, disarticulated, and defleshed. Lengths and condylar shapes of elements with intact epiphyses were measured. Limbs were subsequently completely skeletonized and the measurements repeated. Removal of cartilaginous condylar regions resulted in statistically significant changes in element length and condylar breadth. Moreover, there was marked loss of those cartilaginous structures responsible for joint architecture and congruence. Compared to alligators, birds showed less dramatic, but still significant changes. Condylar morphologies of dinosaur limb bones suggest that most non-coelurosaurian clades possessed large cartilaginous epiphyses that relied on the maintenance of vascular channels that are otherwise eliminated early in ontogeny in smaller-bodied tetrapods. A sensitivity analysis using cartilage correction factors (CCFs) obtained from extant taxa indicates that whereas the presence of cartilaginous epiphyses only moderately increases estimates of dinosaur height and speed, it has important implications for our ability to infer joint morphology, posture, and the complicated functional movements in the limbs of many extinct archosaurs. Evidence suggests that the sizes of sauropod epiphyseal cartilages surpassed those of alligators, which account for at least 10% of hindlimb length. These data suggest that

  14. Comprehensive cooling water study annual report. Volume X: endangered species, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    Federally endangered species which occur on the Savannah River Plant (SRP) include the American alligator, red-cockaded woodpecker, the shortnose sturgeon, and the wood stork. Of these species, only the alligator, sturgeon, and wood stork are likely to be affected by the intake or release of cooling water at the SRP. The nearest colony of wood storks to the SRP is the Birdsville Colony, about 40-45 km southwest of potential foraging areas in the SRP Savannah River swamp. In 1983, it contained about six percent of the nesting pairs in the United States and produced about 250 fledglings. Its reproductive success was about the same in 1984. Based on the results of surveys made of foraging areas, both on SRP and offsite in 1983 and 1984, forage fish availability could be reduced by increased water depths in the Steel Creek delta area following L-Reactor restart with once-through cooling. Effluent discharge from SRP facilities probably limits the potential use of the SRP Savannah River swamp by foraging wood storks. The SRP supports a low-to-moderate alligator population. The current information available on the alligators of the SRP suggests that populations in suitable habitats (e.g., Beaver Dam Creek, Steel Creek, and Par Pond) should continue to benefit from the protection provided by the SRP and should remain stable or continue to increase. Based upon information from the literature and fisheries data for the Savannah River, the operations of the SRP do not appear to have adverse effects on the shortnose sturgeon. Based on known life history characteristics, there is no indication that spawning, rearing, or foraging habitats are affected by SRP operations. 64 refs., 20 figs., 12 tabs.

  15. Lithium metal for x-ray refractive optics

    NASA Astrophysics Data System (ADS)

    Pereira, Nino R.; Arms, Dohn A.; Clarke, Roy; Dierker, Steve B.; Dufresne, Eric; Foster, D.

    2001-12-01

    Lithium is the best material for refractive x-ray lenses, with peak performance around 8 keV. To date we have built a prototype of Cederstrom's so-called alligator lens, and have tested the lens with beamline 7ID's 10 keV x-rays on the Advanced Photon Source at Argonne National Laboratories. To date we have attained only a threefold gain, most likely limited by surface roughness that is avoidable with more careful manufacturing techniques.

  16. Potential molecular wires by an iterative divergent/convergent approach. Doubling of molecular length at each iteration

    NASA Astrophysics Data System (ADS)

    Pearson, Darren L.; Schumm, Jeffry S.; Jones, Leroy, II; Tour, James M.

    1994-06-01

    We have devised an iterative convergent/divergent approach to conjugated oligomers that might serve as molecular wires. The molecular length doubles with each iteration. The systems prepared are completely monodispersed and based upon oligo(thiophene-ethynylene)s (1) and oligo(phenylene-ethynylene)s at 100 A and 128 A long, respectively. The optical and size exclusion chromatography (SEC) properties are discussed. Methods are outlined to attach end groups that might serve as molecular alligator clips.

  17. Surveys of tidal river systems in the northern territory of Australia and their crocodile populations

    SciTech Connect

    Vorlicek, G.C.; Messel, H.; Green, W.J.

    1986-01-01

    This book provides an update on the population dynamics of Crocodylus porous in the tidal waterways of Van Diemen Gulf and the Southern Gulf of Carpentaria, Australia, during 1984 and 1985. Contents: Prologue; Dedication; Introduction; Status of Crocodylus porous. July 1984, in the tidal waterways of the Alligator Region and in the Adelaide River System of Northern Australia: recovery underway; Resurvey of Crocodylus porous populations in the tidal waterways of the southern Gulf of Carpentaria, September - October 1985; Local knowledge - Northern Australia style.

  18. KSC-04PD-0170

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. As Karen Holloway-Adkins, KSC wildlife specialist, begins a tour of the Banana River, this alligator sunning itself attracts attention. Holloway-Adkins is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

  19. The effect of hair bundle shape on hair bundle hydrodynamics of non-mammalian inner ear hair cells for the full frequency range.

    PubMed

    Shatz, Lisa F

    2004-09-01

    The effect of the size and the shape of the hair bundle of a hair cell in the inner ear of non-mammals on its motion for the full range of frequencies is determined thereby extending the results of a previous analysis of hair bundle motion for high and low frequencies [Hear Res. 141 (2000) 39-50]. A hemispheroid is used to represent the hair bundle because it can represent a full range of shapes, from thin, pencil-like shapes to wide, flat, disk-like shapes. Boundary element methods are used to approximate the solution for the hydrodynamics. For physiologically relevant parameters, an excellent match is obtained between the model's predictions and measurements of hair bundle motion in the free-standing region of the basilar papilla of the alligator lizard [Aranyosi, Measuring sound-induced motions of the alligator lizard cochlea. Massachusetts Institute of Technology, PhD Thesis, 2002]. Neither in the model's predictions nor in experimental measurements is sharp tuning observed. The model predicted the low frequency region of neural tuning curves for the alligator lizard and bobtail lizard, but could not predict the sharp tuning or the high frequency region. An element that represents an active mechanism is added to the hair bundle model to predict neural tuning curves, which are sharply tuned, and an excellent match is obtained for all the characteristics of neural tuning curves for the alligator lizard, and for the low and high frequency regions for the bobtail lizard. The model does not predict well the sharp tuning of the shorter hair bundles of the bobtail lizard, possibly because it does not represent tectorial sallets. PMID:15350278

  20. The Everglades Depth Estimation Network (EDEN) surface-water model, version 2

    USGS Publications Warehouse

    Telis, Pamela A.; Xie, Zhixiao; Liu, Zhongwei; Li, Yingru; Conrads, Paul A.

    2015-01-01

    Three applications of the EDEN-modeled water surfaces and other EDEN datasets are presented in the report to show how scientists and resource managers are using EDEN datasets to analyze biological and ecological responses to hydrologic changes in the Everglades. The biological responses of two important Everglades species, alligators and wading birds, to changes in hydrology are described. The effects of hydrology on fire dynamics in the Everglades are also discussed.

  1. Pulmonary anatomy in the Nile crocodile and the evolution of unidirectional airflow in Archosauria.

    PubMed

    Schachner, Emma R; Hutchinson, John R; Farmer, Cg

    2013-01-01

    The lungs of birds have long been known to move air in only one direction during both inspiration and expiration through most of the tubular gas-exchanging bronchi (parabronchi). Recently a similar pattern of airflow has been observed in American alligators, a sister taxon to birds. The pattern of flow appears to be due to the arrangement of the primary and secondary bronchi, which, via their branching angles, generate inspiratory and expiratory aerodynamic valves. Both the anatomical similarity of the avian and alligator lung and the similarity in the patterns of airflow raise the possibility that these features are plesiomorphic for Archosauria and therefore did not evolve in response to selection for flapping flight or an endothermic metabolism, as has been generally assumed. To further test the hypothesis that unidirectional airflow is ancestral for Archosauria, we measured airflow in the lungs of the Nile crocodile (Crocodylus niloticus). As in birds and alligators, air flows cranially to caudally in the cervical ventral bronchus, and caudally to cranially in the dorsobronchi in the lungs of Nile crocodiles. We also visualized the gross anatomy of the primary, secondary and tertiary pulmonary bronchi of C. niloticus using computed tomography (CT) and microCT. The cervical ventral bronchus, cranial dorsobronchi and cranial medial bronchi display similar characteristics to their proposed homologues in the alligator, while there is considerable variation in the tertiary and caudal group bronchi. Our data indicate that the aspects of the crocodilian bronchial tree that maintain the aerodynamic valves and thus generate unidirectional airflow, are ancestral for Archosauria. PMID:23638399

  2. A phenomenological calculus of Wiener description space.

    PubMed

    Richardson, I W; Louie, A H

    2007-10-01

    The phenomenological calculus is a categorical example of Robert Rosen's modeling relation. This paper is an alligation of the phenomenological calculus and generalized harmonic analysis, another categorical example. Our epistemological exploration continues into the realm of Wiener description space, in which constitutive parameters are extended from vectors to vector-valued functions of a real variable. Inherent in the phenomenology are fundamental representations of time and nearness to equilibrium. PMID:17955459

  3. Pulmonary anatomy in the Nile crocodile and the evolution of unidirectional airflow in Archosauria

    PubMed Central

    Hutchinson, John R.; Farmer, CG

    2013-01-01

    The lungs of birds have long been known to move air in only one direction during both inspiration and expiration through most of the tubular gas-exchanging bronchi (parabronchi). Recently a similar pattern of airflow has been observed in American alligators, a sister taxon to birds. The pattern of flow appears to be due to the arrangement of the primary and secondary bronchi, which, via their branching angles, generate inspiratory and expiratory aerodynamic valves. Both the anatomical similarity of the avian and alligator lung and the similarity in the patterns of airflow raise the possibility that these features are plesiomorphic for Archosauria and therefore did not evolve in response to selection for flapping flight or an endothermic metabolism, as has been generally assumed. To further test the hypothesis that unidirectional airflow is ancestral for Archosauria, we measured airflow in the lungs of the Nile crocodile (Crocodylus niloticus). As in birds and alligators, air flows cranially to caudally in the cervical ventral bronchus, and caudally to cranially in the dorsobronchi in the lungs of Nile crocodiles. We also visualized the gross anatomy of the primary, secondary and tertiary pulmonary bronchi of C. niloticus using computed tomography (CT) and microCT. The cervical ventral bronchus, cranial dorsobronchi and cranial medial bronchi display similar characteristics to their proposed homologues in the alligator, while there is considerable variation in the tertiary and caudal group bronchi. Our data indicate that the aspects of the crocodilian bronchial tree that maintain the aerodynamic valves and thus generate unidirectional airflow, are ancestral for Archosauria. PMID:23638399

  4. Evaluation of the Steel Creek ecosystem in relation to the proposed restart of the L-Reactor: interim report

    SciTech Connect

    Not Available

    1983-09-01

    This interim report of findings from studies by SREL has updated information on several key components of the Steel Creek ecosystem. We have emphasized two categories of the Steel Creek biota: Endangered Species (American alligator) and species for which environmental degradation within SRP boundaries might result in changes in offsite resource abundance. Wintering waterfowl surveys in the vicinity of the Steel Creek delta have demonstrated a pattern of increased utilization over the duration of these studies (1981-83). Wood stork utilization of SRP swamp areas also appeared to be substantially increased relative to previous years. Thermal alteration of the Steel Creek delta areas will eliminate this area as wood stork foraging habitat. Anadromous fish utilization of the Steel Creek area was also substantially increased in 1983 relative to 1982. The differences in anadromous fish species utilization patterns between 1982 and 1983 are probably a result of the markedly different river flow conditions between the two years. Studies of the American alligator have continued. No further reproduction by alligators has been observed in the Steel Creek system. 24 references, 14 figures, 13 tables.

  5. Advances in molecular electronics: Synthesis and testing of potential molecular electronic devices

    NASA Astrophysics Data System (ADS)

    Price, David Wilson, Jr.

    New potential molecular electronics devices have been synthesized based on our knowledge of previous systems that have come out of our group. Previous studies and current studies have shown that simple molecular systems demonstrate negative differential resistance (NDR) and memory characteristics. The new systems rely primarily on the redox properties of the compounds to improve upon the solid state properties already observed. Most of these new organic compounds use thiol-based "alligator clips" for attachment to metal surfaces. Some of the compounds, however, contain different "alligator clips," primarily isonitriles, for attachment to metal substrates. It is our hope that these new "alligator clips" will offer lower conductivity barriers (higher current density). Electrochemical tests have been performed in order to evaluate those redox properties and in the hope of using those electrochemical results as a predictive tool to evaluate the usefulness of those compounds. Also, organic structures with polymerizable functionalities have been synthesized in order to cross-link the molecules once they are a part of a self-assembled monolayer (SAM). This has been shown to enable the electrochemical growth of polypyrrole from a SAM in a controllable manner.

  6. Threatened and Endangered Species Survey for Patrick Air Force Base, Florida

    NASA Technical Reports Server (NTRS)

    Oddy, Donna M.; Stolen, Eric D.; Schmalzer, Paul A.; Larson, Vickie L.; Hall, Patrice; Hensley, Melissa A.

    1997-01-01

    characteristic of species that occur in the Indian River Lagoon system. Twenty-five species of waterbirds were observed during quarterly surveys on PAFB, including five species listed as species of special concern by the state of Florida: Snowy Egret (Egretta thula), Little Blue Heron (Egretta caerulea), Tricolored Heron (Egretta tricolo4, White Ibis (Eudocimus albus), and Brown Pelican (Pelecanus occidentalis). The Golf Course was used extensively by almost all species of waterbirds on PAFB. Twenty-two species of shorebirds were observed on PAFB. Although no listed species were observed, the potential exists for several protected species of shorebirds to use the beach at PAFB during some parts of the year. The Airfield runways and associated grass areas were important sites at PAFB for loafing and feeding for some shorebirds. Surveys of rooftop nesting by Least Terns (Stema antillarum) on PAFB found a large colony on a rooftop in the PAFB Industrial Area. This colony produced some independent young. Two rooftop Least Tern colonies reported from previous years were inactive during 1996. A small number of Black Skimmers (Rhynchops nigee attempted to nest at the Least Ten colony but were unsuccessful. Surveys for the gopher tortoise (Gopherus polyphemus) revealed burrows and tortoises only at the Waste Study Site; five burrows and three tortoises were observed. No Florida scrub lizards (Sceloporus woodi), eastern indigo snakes (Drymarchon corais couperl), or diamondback terrapins (Malademys terrapin terrapin) were observed. American alligators (Alligator mississippiensis) were observed on the Golf Course and using ditches, ponds, and areas along the Banana River. The amount of dune habitat could be expanded by not mowing areas adjacent to the dunes to allow dune species to colonize and expand. Planting dune species as part of the beach renourishment project will also increase this habitat. Exotic plants dominate several areas on the base and are used by threatened, endangered, and

  7. Hydrothermal systematics, alteration, and mineralization in the Grant Canyon, Bacon Flat, and Blackburn Oil Fields, Nevada - Intriguing Parallels with Carlin-Type gold deposits

    SciTech Connect

    Hulen, J.B.; Nielson, D.L. )

    1993-08-01

    Nevada's three known thermally active oil reservoirs-Blackburn, Bacon Flat, and Grand Canyon-share a surprisingly long list of essential attributes with the Carlin-type, low-grade, sediment-hosted gold deposits, particularly those of the Alligator Ridge mining district. Like these rich precious-metal ore bodies, the three fields (1) are hosted by Paleozoic carbonate and calcareous silici-clastic strata; (2) occur in structural or structural/stratigraphic traps sealed beneath shales or hydrothermally argillized and silicified tuffs and epiclastic debris, (3) have undergone intense fracturing and brecciation, as well as massive hydrothermal decalcification as major porosity-creating processes; (4) occupy rocks partly altered to or veined by the secondary-mineral assemblage quartz-kaolin-barite-pyrite-marcasite; (5) have a direct geothermal connection; (6) are enriched in the elements arsenic, antimony, mercury, thallium, and even contain significant traces of gold-up 50 ppb in altered Mississippian Chainmain Shale in the Blackburn field. Moreover, measured temperatures, as well as late-stage, fluid-inclusion homogenization temperatures (T[sub h]) at the fields-all in the range 100-135[degrees]C-fall within the fluid-inclusion T[sub h] span of 90-165[degrees]C recorded for multiple Alligator Ridge deposits. Fracture-controlled live oil and oil-bearing fluid inclusions in some of the Alligator Ridge ores provide further evidence of genetic similarities with the oil reservoirs. The authors suggest that the three oil fields could represent either weakly mineralized analogs of the gold deposits or an incipient phase in their evolution ultimately leading to ore mineralization.

  8. Olfactory Receptor Subgenomes Linked with Broad Ecological Adaptations in Sauropsida.

    PubMed

    Khan, Imran; Yang, Zhikai; Maldonado, Emanuel; Li, Cai; Zhang, Guojie; Gilbert, M Thomas P; Jarvis, Erich D; O'Brien, Stephen J; Johnson, Warren E; Antunes, Agostinho

    2015-11-01

    Olfactory receptors (ORs) govern a prime sensory function. Extant birds have distinct olfactory abilities, but the molecular mechanisms underlining diversification and specialization remain mostly unknown. We explored OR diversity in 48 phylogenetic and ecologically diverse birds and 2 reptiles (alligator and green sea turtle). OR subgenomes showed species- and lineage-specific variation related with ecological requirements. Overall 1,953 OR genes were identified in reptiles and 16,503 in birds. The two reptiles had larger OR gene repertoires (989 and 964 genes, respectively) than birds (182-688 genes). Overall, birds had more pseudogenes (7,855) than intact genes (1,944). The alligator had significantly more functional genes than sea turtle, likely because of distinct foraging habits. We found rapid species-specific expansion and positive selection in OR14 (detects hydrophobic compounds) in birds and in OR51 and OR52 (detect hydrophilic compounds) in sea turtle, suggestive of terrestrial and aquatic adaptations, respectively. Ecological partitioning among birds of prey, water birds, land birds, and vocal learners showed that diverse ecological factors determined olfactory ability and influenced corresponding olfactory-receptor subgenome. OR5/8/9 was expanded in predatory birds and alligator, suggesting adaptive specialization for carnivory. OR families 2/13, 51, and 52 were correlated with aquatic adaptations (water birds), OR families 6 and 10 were more pronounced in vocal-learning birds, whereas most specialized land birds had an expanded OR family 14. Olfactory bulb ratio (OBR) and OR gene repertoire were correlated. Birds that forage for prey (carnivores/piscivores) had relatively complex OBR and OR gene repertoires compared with modern birds, including passerines, perhaps due to highly developed cognitive capacities facilitating foraging innovations. PMID:26219582

  9. Light O{sup ++} Mesons: Scalargators in Florida

    SciTech Connect

    Pennington, M. R.

    2010-08-05

    Light scalar mesons abound in hadron processes, like the alligators in the Florida Everglades. Moreover, scalars are intimately tied to the vacuum structure of QCD. They are the product of many decays. Consequently, a rich source of recent information about them has come from experiments producing heavy flavour mesons. Indeed, scalars will continue to dominate many of the processes to be studied at forthcoming facilities like BESIII in Beijing, FAIR at GSI Darmstadt and the GlueX experiment at JLab, making an understanding (or at least an excellent and theoretically consistent description) essential for the physics missions of these facilities.

  10. Light O++ Mesons: Scalargators in Florida

    NASA Astrophysics Data System (ADS)

    Pennington, M. R.

    2010-08-01

    Light scalar mesons abound in hadron processes, like the alligators in the Florida Everglades. Moreover, scalars are intimately tied to the vacuum structure of QCD. They are the product of many decays. Consequently, a rich source of recent information about them has come from experiments producing heavy flavour mesons. Indeed, scalars will continue to dominate many of the processes to be studied at forthcoming facilities like BESIII in Beijing, FAIR at GSI Darmstadt and the GlueX experiment at JLab, making an understanding (or at least an excellent and theoretically consistent description) essential for the physics missions of these facilities.

  11. Metal Fatigue Causing Cystoscope Rupture During Bladder Neck Incision

    PubMed Central

    Fernandez, Alfonso

    2011-01-01

    The modern cystoscope is the result of the advancement in technology in numerous areas and is an invaluable tool that allows the urologist to perform a number of diagnostic and therapeutic procedures. Although various degrees of endoscope failure have been widely reported, instrument breakage that leads to a foreign body has not. While performing a bladder neck stricture incision for a 72-year-old male patient with a previous radical prostatectomy for prostate cancer and a resulting bladder neck stricture, we documented a major 17-French cystoscope malfunction and a resulting foreign body that was retrieved from the bladder using a 22-French scope and alligator forceps. PMID:21985739

  12. Geothermal pipeline: Progress and development update from the geothermal progress monitor

    SciTech Connect

    1996-11-01

    This document is a progress and development update from the Geothermal Progress Monitor prepared by the Geo-Heat Center at the Oregon Institute of Technology in Klamath Falls, Oregon. Several upcoming meetings and workshops in the field of geothermal energy and resource development are announced. Geothermal exploration and development projects in several areas are described in this document: New San Luis Valley Training Program, Fish and Alligator Ranching in Idaho, the geothermal drilling operation at Newberry Volcanic Crater near Bend, Oregon, and Australian Red Claw Lobster raised in aquaculture ponds at Belmont Hot Springs, Utah.

  13. Current shot noise characteristics in biphenyl diamine and biphenyl dithiol devices

    NASA Astrophysics Data System (ADS)

    kalsoom, Ambreen; Song, Siyu; Li, Guiqin

    2014-09-01

    Current shot noise characteristics, away from their average current, in biphenyl diamine and biphenyl dithiol devices are investigated. The relations among the shot noise and the applied bias, the coupling factors, as well as the alligator clips are revealed. The regular change of the shot noise in biphenyl diamine device and irregular change of the shot noise in biphenyl dithiol device are shown as the coupling strength change from full coupling to weak coupling. It is found that the shot noise suppression in biphenyl diamine device is enhanced at the higher bias. The large differences of the shot noise suppression in the biphenyl dithiol device are revealed.

  14. A Novel Endoscopic Method to Relieve Food Impaction Using an Inflatable Balloon.

    PubMed

    Anand, Rohit; Garg, Shashank; Dubin, Ethan; Dutta, Sudhir

    2015-01-01

    Food impaction in the esophagus is a relatively common medical emergency. Most of these food impactions are relieved spontaneously. But for complete esophageal food impactions or impactions not relieved spontaneously, traditional endoscopic methods like using a Roth net, polypectomy snare, or rat or alligator tooth forceps are used to gently manipulate the food material into the stomach. However, these methods may not work in certain circumstances. We present a case of proximal esophageal food impaction that was relieved using an inflatable balloon after the conventional methods proved unsuccessful. PMID:26266059

  15. Impacted Sharp Oesophageal Foreign Bodies--A Novel Technique of Removal with the Paediatric Bronchoscope.

    PubMed

    Mitra, Aparajita; Bajpai, Minu

    2016-04-01

    Sharp foreign bodies in the oesophagus may present as an entirely asymptomatic child with only radiological evidence but require emergent surgical management. Safety pins, razor blades and needles are a few of the commonly ingested sharp objects in developing countries. The open safety pin is a particularly interesting clinical problem, as the management depends on its location and orientation. Many methods and instruments have been used over the years to remove them from the upper digestive tract. We present a novel method using the rigid paediatric bronchoscope and alligator forceps for the extraction of this unusual foreign body from the oesophagus of a 6 year old girl. PMID:26851436

  16. KSC-05PD-1705

    NASA Technical Reports Server (NTRS)

    2005-01-01

    KENNEDY SPACE CENTER, FLA. In a pond near Launch Pad 39B, an alligator lurks near the tall grass. Nearby is Space Shuttle Discovery, in full launch configuration after rollback of the Rotating Service Structure (RSS). Rollback of the RSS is a major preflight milestone, typically occurring during the T-11-hour hold on L-1 (the day before launch). Discovery is scheduled to lift off on the historic Return to Flight mission STS-114 at 10:39 a.m. EDT July 26 with a crew of seven.

  17. A Micromechanical Contribution to Cochlear Tuning and Tonotopic Organization

    NASA Astrophysics Data System (ADS)

    Holton, Thomas; Hudspeth, A. J.

    1983-11-01

    The response properties of hair cells and nerve fibers in the alligator lizard cochlea are frequency selective and tonotopically organized with longitudinal position in the organ. The lengths of the hair-cell hair bundles also vary monotonically with longitudinal position. In this study, quantitative measurements were made of the motion of individual hair bundles in an excised preparation of the cochlea stimulated at auditory frequencies. The angular displacement of hair bundles is frequency selective and tonotopically organized, demonstrating the existence of a micromechanical tuning mechanism.

  18. Nondestructive measurement of large objects with electron paramagnetic resonance: Pottery, sculpture, and jewel ornament

    NASA Astrophysics Data System (ADS)

    Ikeya, Motoji; Yamamoto, Masahiro; Ishii, Hiroshi

    1994-12-01

    A cylindicral cavity of TE111 mode with an aperture of 3 mm in diameter has been used to measure the electron paramagnetic resonance (EPR) spectrum of a large object placed over the aperture. EPR spectra of a precious fossil of a dinosaur tooth piece and a fossil bone of the Machikane Alligator were measured nondestructively in addition to a jadeite sculpture, a pearl and turquoise necklace, a large turmaline, a star ruby, and ceramic pottery. Thus, EPR can be a nondestructive tool to detect forgery and to test the authenticity in art as well as to allocate ancient objects in archaeological provenance study.

  19. KSC-05PD-1706

    NASA Technical Reports Server (NTRS)

    2005-01-01

    KENNEDY SPACE CENTER, FLA. In a pond near Launch Pad 39B, an alligator lurks near the tall grass on the lower right side. In the background is Space Shuttle Discovery, in full launch configuration after rollback of the Rotating Service Structure (RSS). Rollback of the RSS is a major preflight milestone, typically occurring during the T-11-hour hold on L-1 (the day before launch). Discovery is scheduled to lift off on the historic Return to Flight mission STS-114 at 10:39 a.m. EDT July 26 with a crew of seven.

  20. Swamp to Space exhibit

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The menacing-looking alligator is really harmless. It is one of the realistic props to help convince visitors that the feel of the swamp is real in StenniSphere's Swamp to Space exhibit at John C. Stennis Space Center in Hancock County, Miss. The historical section of the Swamp to Space exhibit tells the story of why and how Stennis Space Center came to be. It also pays tribute to the families who moved their homes to make way for the space age in Mississippi.

  1. Direct comparison of the electronic coupling efficiency of sulfur and selenium anchoring groups for molecules adsorbed onto gold electrodes

    NASA Astrophysics Data System (ADS)

    Patrone, L.; Palacin, S.; Bourgoin, J. P.; Lagoute, J.; Zambelli, T.; Gauthier, S.

    2002-08-01

    We performed air and ultra-high vacuum scanning tunneling microscopy experiments in order to compare the electronic coupling provided by S and by Se used as alligator clips for bisthiol- and biselenol-terthiophene molecules adsorbed onto gold. The molecules were inserted in a dodecanethiol self-assembled monolayer. Their apparent height above the dodecanethiol matrix was used as a measure of the electronic coupling strength corresponding to S and Se, respectively. We show that the insertion behaviors of the two molecules are qualitatively the same, and that Se provides systematically a better coupling link than S whatever the tunneling conditions.

  2. KSC-05PD-1704

    NASA Technical Reports Server (NTRS)

    2005-01-01

    KENNEDY SPACE CENTER, FLA. In a pond near Launch Pad 39B, an alligator lurks near the tall grass. Nearby is Space Shuttle Discovery, in full launch configuration after rollback of the Rotating Service Structure (RSS). Rollback of the RSS is a major preflight milestone, typically occurring during the T-11-hour hold on L-1 (the day before launch). Discovery is scheduled to lift off on the historic Return to Flight mission STS-114 at 10:39 a.m. EDT July 26 with a crew of seven.

  3. Active oil seep at Nevada gold mine holds intrigue for more exploration

    SciTech Connect

    Pinnell, M.L.; Blake, J.G. ); Hulen, J.B. )

    1991-07-15

    This paper reports on an active oil seep has been discovered in one of Nevada's famous Carlin-type low grade disseminated gold deposits. This unique seep, at the Yankee gold mine in White Pine County, may have important implications for both oil and gas and gold exploration in the Basin and Range province of the western U.S. The open pit Yankee mine, near the western margin of Long Valley, exploits one of numerous Carlin-type gold ore bodies in the alligator Ridge mining district; all are currently owned and operated by USMX Corp.

  4. Climate changes, shifting ranges

    USGS Publications Warehouse

    Romanach, Stephanie

    2015-01-01

    Even a fleeting mention of the Everglades conjures colorful images of alligators, panthers, flamingos, and manatees. Over the centuries, this familiar cast of characters has become synonymous with life in south Florida. But the workings of a changing climate have the potential to significantly alter the menagerie of animals that call this area home. Global projections suggest south Florida wildlife will need to contend with higher temperatures, drier conditions, and rising seas in the years ahead. Recent modeling efforts shed new light on the potential outcomes these changes may have for threatened and endangered species in the area.

  5. A Universal Spring-Probe System for Reliable Probing of Electrochemical Lab-on-a-Chip Devices

    PubMed Central

    Lee, Moon-Keun; Lee, Tae Jae; Choi, Ho Woon; Shin, Su Jeong; Park, Jung Youn; Lee, Seok Jae

    2014-01-01

    For achieve sensitivity in lab-on-a-chip electrochemical detection, more reliable probing methods are required, especially for repeated measurements. Spring-probes are a promising candidate method which can replace needle-like probes and alligator clips that usually produce scratches on the surface of gold electrodes due to the strong physical contacts needed for electrochemical measurements. The superior reliability of amperometric measurements by a spring-probe system was compared with results by conventional probing methods. We demonstrated that a universal spring-probe system would be potentially suitable to achieve high performance in lab-on-a-chip devices using electrochemical detection. PMID:24406857

  6. A new species of glossiphoniid leech from Rana pretiosa (Amphibia: Ranidae) in Oregon.

    PubMed

    Siddall, Mark E; Bowerman, Jay

    2006-08-01

    A new species of ectoparasitic glossiphoniid leech was found feeding on frogs in the Nature Center Pond and elsewhere in Deschutes County, Oregon. The new species of Placobdella resembles the southern alligator leech, Placobdella multilineata Moore, 1953, notwithstanding their vast geographic separation in North America. The new species is readily distinguished by possessing subdivided annuli, by its papillation and pigmentation patterns as well as by the arrangement of ovarian tissues. There is strong evidence of nocturnality and of the potential for parasitizing humans. PMID:16995404

  7. A continuation of base-line studies for environmentally monitoring Space Transportation Systems (STS) at John F. Kennedy Space Center. Volume 4: Threatened and endangered species of the Kennedy Space Center. Part 2: Threatened and endangered birds and other threatened and endangered forms

    NASA Technical Reports Server (NTRS)

    Ehrhart, L. M.

    1980-01-01

    Data are presented which were collected by ground and aerial surveillance of 37 species of birds observed within the environs of KSC which are on lists of rare and endangered biota in Florida. Additional information was obtained on other threatened species such as the West Indian manatee, the salt marsh snake, the Indigo snake, the Gopher tortoise, the American alligator, and the Florida mouse. Results of the literature search were used to obtain a historical perspective and aid in the analysis of the field data collected.

  8. BioPartnering North America--Programs from Pharma in Europe and the Middle East.

    PubMed

    Croydon, Léonie

    2010-03-01

    The BioPartnering North America conference, held in Vancouver, included presentations covering drug pipeline developments from both large and small pharmaceutical companies. This conference report highlights selected presentations from drug developers from Europe and the Middle East, specifically France, Spain, Denmark, Ireland, Sweden, Switzerland, Germany and Israel. Investigational drugs discussed include naproxcinod and NCX-116 (both NicOx SA), beta-amyloid (Abeta)40- and Abeta42-targeting vaccines (Araclon Biotech SI), ROSE-010 (Rose Pharma A/S), ADC-1004 (Alligator Bioscience AB), and VPM-4-001 (Vakzine Projekt Management GmbH). PMID:20191431

  9. Harlequin ichthyosis: Case report

    PubMed Central

    Salehin, Shahrbanoo; Azizimoghadam, Ahmad; Abdollahimohammad, Abdolghani; Babaeipour-Divshali, Mohammad

    2013-01-01

    Harlequin fetus is a rare and the most severe form of the congenital ichthyosis with an autosomal recessive inheritance. Incidence of the disease is nearly 1 in 3,00,000 live births. The disease might be lethal at birth and the affected babies are often premature. Harlequin ichthyosis (HI) is marked by severe keratinized and alligator-like horned skin. The present study reports a new case with HI and adds to the collective knowledge of this rare skin disorder. HI has been linked to mutation in the ABCA12 gene; therefore, genetic counseling and mutation screening of this gene should be considered. PMID:24520234

  10. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  11. A New Class of SINEs with snRNA Gene-Derived Heads

    PubMed Central

    Kojima, Kenji K.

    2015-01-01

    Eukaryotic genomes are colonized by various transposons including short interspersed elements (SINEs). The 5′ region (head) of the majority of SINEs is derived from one of the three types of RNA genes—7SL RNA, transfer RNA (tRNA), or 5S ribosomal RNA (rRNA)—and the internal promoter inside the head promotes the transcription of the entire SINEs. Here I report a new group of SINEs whose heads originate from either the U1 or U2 small nuclear RNA gene. These SINEs, named SINEU, are distributed among crocodilians and classified into three families. The structures of the SINEU-1 subfamilies indicate the recurrent addition of a U1- or U2-derived sequence onto the 5′ end of SINEU-1 elements. SINEU-1 and SINEU-3 are ancient and shared among alligators, crocodiles, and gharials, while SINEU-2 is absent in the alligator genome. SINEU-2 is the only SINE family that was active after the split of crocodiles and gharials. All SINEU families, especially SINEU-3, are preferentially inserted into a family of Mariner DNA transposon, Mariner-N4_AMi. A group of Tx1 non-long terminal repeat retrotransposons designated Tx1-Mar also show target preference for Mariner-N4_AMi, indicating that SINEU was mobilized by Tx1-Mar. PMID:26019167

  12. Using scenario planning to evaluate the impacts of climate change on wildlife populations and communities in the Florida Everglades.

    PubMed

    Catano, Christopher P; Romañach, Stephanie S; Beerens, James M; Pearlstine, Leonard G; Brandt, Laura A; Hart, Kristen M; Mazzotti, Frank J; Trexler, Joel C

    2015-04-01

    It is uncertain how climate change will impact hydrologic drivers of wildlife population dynamics in freshwater wetlands of the Florida Everglades, or how to accommodate this uncertainty in restoration decisions. Using projections of climate scenarios for the year 2060, we evaluated how several possible futures could affect wildlife populations (wading birds, fish, alligators, native apple snails, amphibians, threatened and invasive species) across the Everglades landscape and inform planning already underway. We used data collected from prior research and monitoring to parameterize our wildlife population models. Hydrologic data were simulated using a spatially explicit, regional-scale model. Our scenario evaluations show that expected changes in temperature, precipitation, and sea level could significantly alter important ecological functions. All of our wildlife indicators were negatively affected by scenarios with less rainfall and more evapotranspiration. Under such scenarios, habitat suitability was substantially reduced for iconic animals such as wading birds and alligators. Conversely, the increased rainfall scenario benefited aquatic prey productivity and apex predators. Cascading impacts on non-native species is speculative, but increasing temperatures could increase the time between cold events that currently limit expansion and abundance of non-native fishes, amphibians, and reptiles with natural ranges in the tropics. This scenario planning framework underscored the benefits of proceeding with Everglades restoration plans that capture and clean more freshwater with the potential to mitigate rainfall loss and postpone impacts of sea level rise. PMID:25371194

  13. Neuromuscular diversity in archosaur deep dorsal thigh muscles.

    PubMed

    Gatesy, S M

    1994-01-01

    The living members of the clade Archosauria, crocodilians and birds, differ markedly in the morphology of their deep dorsal thigh muscles. To investigate whether this diversity is accompanied by differences in motor pattern and muscle function, the hindlimbs of representative archosaurs were studied by electromyography and cineradiography during terrestrial locomotion. In a crocodilian, Alligator, the iliofemoralis and pubo-ischio-femoralis internus part 2 are both active during the swing phase of the stride cycle. This appears to be the primitive motor pattern for archosaurs. There are four avian homologues of these muscles in the helmeted guineafowl, Numida. These are primarily active in the propulsive phase (iliotrochantericus caudalis and iliotrochantericus medius), the swing phase (iliotrochantericus cranialis) and a speed-dependent combination of the propulsive and/or swing phases (iliofemoralis externus). Differences between Alligator and Numida in the number and attachment of deep dorsal muscles are associated with dissimilar motor patterns and functions. Evolutionary modifications of neuromuscular control must be recognized when evaluating avian locomotor history, but are rarely considered by paleontologists. Even within the deep dorsal thigh muscles of Numida, developmentally and anatomically similar muscles are active out-of-phase. Therefore, although the actions of two adjacent muscles appear equivalent, their functions may differ dramatically. The diversity of deep dorsal thigh muscles in modern birds may be a good model for studying the relationship between activity pattern and peripheral morphology. PMID:8306187

  14. Limited species differences in estrogen receptor alpha-medicated reporter gene transactivation by xenoestrogens.

    PubMed

    Sumida, Kayo; Ooe, Norihisa; Saito, Koichi; Kaneko, Hideo

    2003-01-01

    Estrogen receptors (ERs) play an important role in estrogen function. However, it is well known that there are species differences in amino acid sequences of the ligand binding domains. Here, we report on the analysis of species differences in ER-dependent transactivation with some chemicals using reporter gene assays. Full-length ER cDNAs from human, rat, chicken, alligator (Caiman), whiptail lizard, African clawed frog and rainbow trout were prepared from hepatic mRNA by the RT-PCR method and inserted into expression plasmids. Both expression and reporter plasmids were transiently transfected into HeLa cells, and then the estrogenic effects of chemicals were analyzed in terms of induction of luciferase activity. No species differences in transactivation were found among human, rat, chicken, alligator, whiptail lizard and African clawed frog ERs. However, thermo-dependent alteration in susceptibility to 17-beta-estradiol was observed with the rainbow trout ER because of thermo-dependence of estrogen binding. PMID:12648522

  15. An Overview of My Internship with the Ecological Program at John F. Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Owen, Samantha

    2010-01-01

    During my internship with Innovative Health Applications, I participated in numerous longterm research projects involving the study of various plant and animal life at the Kennedy Space Center (KSC). I observed the monitoring of nesting sea turtles. I learned about the transfer of egg clutches from the northern Gulf Coast in an effort to help the hatchlings avoid the oil spill in the Gulf of Mexico. I gained knowledge of tracking the movements of important sport fish and sharks in this area using a hydro-acoustic tag and receiver system. This effort included routinely taking water quality data at multiple sites around KSC. Alligator population and nesting assessments was another part of my internship. I observed the biologists take morphometric measurements, blood, urine and tissue samples from alligators found in KSC waterways. I assisted in taking photosynthesis and reflectance measurements on various scrub oaks and palmettos. I participated in Florida Scrub-Jay surveys in an effort to monitor their population trends and was involved in Southeastern beach mouse trapping and identification. I also assisted in seagrass surveys monitoring the health of the seagrass beds.

  16. Chromosome-scale shotgun assembly using an in vitro method for long-range linkage.

    PubMed

    Putnam, Nicholas H; O'Connell, Brendan L; Stites, Jonathan C; Rice, Brandon J; Blanchette, Marco; Calef, Robert; Troll, Christopher J; Fields, Andrew; Hartley, Paul D; Sugnet, Charles W; Haussler, David; Rokhsar, Daniel S; Green, Richard E

    2016-03-01

    Long-range and highly accurate de novo assembly from short-read data is one of the most pressing challenges in genomics. Recently, it has been shown that read pairs generated by proximity ligation of DNA in chromatin of living tissue can address this problem, dramatically increasing the scaffold contiguity of assemblies. Here, we describe a simpler approach ("Chicago") based on in vitro reconstituted chromatin. We generated two Chicago data sets with human DNA and developed a statistical model and a new software pipeline ("HiRise") that can identify poor quality joins and produce accurate, long-range sequence scaffolds. We used these to construct a highly accurate de novo assembly and scaffolding of a human genome with scaffold N50 of 20 Mbp. We also demonstrated the utility of Chicago for improving existing assemblies by reassembling and scaffolding the genome of the American alligator. With a single library and one lane of Illumina HiSeq sequencing, we increased the scaffold N50 of the American alligator from 508 kbp to 10 Mbp. PMID:26848124

  17. Salinity effects on photosynthesis and growth in Alternanthera philoxeroides (Mart. ) Griseb

    SciTech Connect

    Longstreth, D.J.; Bolanos, J.A.; Smith, J.E.

    1984-08-01

    Alternanthera philoxeroides, alligator weed, was grown at five different NaCl concentrations to determine the effect of salinity on factors related to the net rate of CO/sub 2/ uptake (P/sub n/). Over the range of 0 to 400 millimolar NaCl, P/sub n/ declined 51%. Stomatal conductance declined in parallel with P/sub n/ and as a result there was no reduction in intercellular CO/sub 2/ concentrations and therefore no reduction in the amount of CO/sub 2/ available for photosynthesis. The CO/sub 2/ compensation point did not change with salt stress. Increases in leaf thickness tended to compensate slightly for the negative effects of salinity on leaf cell metabolism, at least in relation to P/sub n/. On a mesophyll cell area basis, soluble protein was relatively constant in leaves developed at 100 to 400 millimolar NaCl while total chlorophyll decreased at all salinities. Dry weight production and P/sub n/ were closely correlated in alligator weed grown at different salinities. Plants produced less leaf area per unit dry weight as salinity increased, which may aid in water conservation. 26 references, 5 figures, 2 tables.

  18. Research on uranium deposits as analogies of radioactive waste repositories

    SciTech Connect

    Hardy, C.J.

    1988-01-01

    The disposal of highly radioactive waste deep underground in suitable geological formations is proposed by many countries to protect public health and safety. The study of natural analogies of nuclear waste repositories is one method of validating mathematical models and assuring that a proposed repository site and design will be safe. Since 1981, the AAEC has studied the major uranium deposits in the Alligator Rivers region of the Northern Territory of Australia as natural analogues of radioactive waste repositories. Results have been obtained on the following: (1) the migration of uranium, thorium and radium isotopes, (2) the behavior of naturally occurring levels of selected fission products and transuranium nuclides, e.g. technetium-99, iodine-129 and plutonium-239; (3) the role of specific minerals in retarding migration, and (4) the importance of colloidal material, in the migration of thorium. The AAEC has initiated a wider international project entitled The Alligator Rivers Analogue Project which will enable participating organizations to obtain additional results and to apply them in modeling, planning and regulating waste repositories.

  19. Postembryonic Nephrogenesis and Persistence of Six2-Expressing Nephron Progenitor Cells in the Reptilian Kidney.

    PubMed

    Camarata, Troy; Howard, Alexis; Elsey, Ruth M; Raza, Sarah; O'Connor, Alice; Beatty, Brian; Conrad, Jack; Solounias, Nikos; Chow, Priscilla; Mukta, Saima; Vasilyev, Aleksandr

    2016-01-01

    New nephron formation (nephrogenesis) ceases in mammals around birth and is completely absent in adults. In contrast, postembryonic nephrogenesis is well documented in the mesonephric kidneys of fishes and amphibians. The transient mesonephros in reptiles (including birds) and mammals is replaced by the metanephros during embryogenesis. Thus, one may speculate that postembryonic nephrogenesis is restricted to the mesonephric kidney. Previous reports have suggested the metanephros of non-avian reptiles (hereafter reptiles) may continually form nephrons throughout life. We investigated the presence of adult nephrogenesis in reptiles by examining adult kidneys from several species including Trachemys scripta, Chrysemys picta, Boa constrictor, Tupinambis tegu, Anolis carolinensis, and Alligator mississipiensis among others. We found that all major reptilian groups (Testudines, Crocodylia, and Squamates) showed the presence of adult nephrogenesis. The total amount of nephrogenesis varied greatly between species with turtles displaying the highest density of nephrogenesis. In contrast, we were unable to detect adult nephrogenesis in monotremes, and in the iguanid A. carolinensis. Nephron progenitor cells express the transcription factor Six2, which in mammals, becomes downregulated as the progenitor cell population is exhausted and nephrogenesis ends. Using the alligator as a model, we were able to detect Six2-positive cap mesenchyme cells in the adult kidney, which spatially correlated with areas of nephrogenesis. These results suggest that the metanephric kidney of reptiles has maintained the ability to continually grow new nephrons during postembryonic life, a process lost early in mammalian evolution, likely due to the persistence of a Six2-expressing progenitor cell population. PMID:27144443

  20. Comprehensive Cooling Water Study: Volume 6, Federally endangered species, Savannah River Plant: Final report

    SciTech Connect

    Mackey, H.E.

    1987-09-01

    The Comprehensive Cooling Water Study (CCWS) was initiated in 1983 to evaluate the environmental effects of the intake and release of cooling water on the structure and function of aquatic ecosystems at the Savannah River Plant. The initial report described the results from the first year of the study. This document is the final report and concludes the program. The report comprises eight volumes. The Endangered Species Act requires that Federal agencies use their authorities to conduct programs for the conservation of endangered and threatened species and to ensure that agency actions do not jeopardize the continued existence of or result in the destruction or adverse modification of critical habitat of protected species. Those Federally endangered or threatened species that occur on the Savannah River Plant (SRP) include the American alligator, the red-cockaded woodpecker, the shortnose sturgeon, the wood stork, and the bald eagle. Of these species, the alligator, sturgeon, wood stork, and the bald eagle are likely to be affected directly and/or indirectly by the intake or release of cooling water at the SRP. 81 refs., 76 figs., 35 tabs.