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1

Getting to Know Homo erectus  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Europe and Asia have yielded a number of hominid fossils from the period 1 to 0.5 million years ago, but few hominid fossils from this era have been found in Africa. In his Perspective, Schwartz discusses a new hominid fossil find at Olorgesailie in Kenya, and whether it belongs to the species Homo erectus.

Jeffrey H. Schwartz (University of Pittsburgh;)

2004-07-02

2

The subspecies of Homo erectus  

Microsoft Academic Search

ClassifyingHomo erectus into subspecies can be based on either temporal or geographical differences, but there is no accepted system for using both.\\u000a This can be done with subspecies names consisting of two elements — a prefix ofneo, meso, orpaleo to indicate grade, followed by a geographical term ofeuropus, africus, sinicus, orindicus to indicate line. Thus Rhodesian isHomo erectus neoafricus, Ngandong

G. S. Krantz

1993-01-01

3

Homo erectus brain sizes by subspecies  

Microsoft Academic Search

Homo erectus fossils can be divided into four zoogeographic zones that show different rates of endocranial expansion during the Pleistocene.\\u000a When these are also grouped into three time levels, we find small increases from early to middle forms, and regularly greater\\u000a increases from middle to late forms. These increases fit a regular pattern that also accomodates all archaic types, including

G. S. Krantz

1995-01-01

4

Homo erectus from Nanjing  

Microsoft Academic Search

The Huludong Cave (Calabash Cave) is a karst cave in the Tangshan hills, just east of Nanjing, China. An investigation in 1992 by members of the Nanjing Institute of Geology and Paleontology (NIGP) recovered numerous mammalian fossils, and a joint work team was assembled from members of the NIGP and the IVPP (Institute for Vertebrate Paleontology and Paleoanthropology) in Beijing.

Wu Rukang; Wu Xinzhi; Mu Xinan; Milford H. Wolpoff

2004-01-01

5

Grandmothering and the evolution of homo erectus.  

PubMed

Despite recent, compelling challenge, the evolution of Homo erectus is still commonly attributed to big game hunting and/or scavenging and family provisioning by men. Here we use a version of the "grandmother" hypothesis to develop an alternative scenario, that climate-driven adjustments in female foraging and food sharing practices, possibly involving tubers, favored significant changes in ancestral life history, morphology, and ecology leading to the appearance, spread and persistence of H. erectus. Available paleoclimatic, environmental, fossil and archaeological data are consistent with this proposition; avenues for further critical research are readily identified. This argument has important implications for widely-held ideas about the recent evolution of long human lifespans, the prevalence of male philopatry among ancestral hominids, and the catalytic role of big game hunting and scavenging in early human evolution. PMID:10222165

O'connell, J F; Hawkes, K; Blurton Jones, N G

1999-05-01

6

The taxonomic implications of cranial shape variation in Homo erectus  

Microsoft Academic Search

The taxonomic status of Homo erectus sensu lato has been a source of debate since the early 1980s, when a series of publications suggested that the early African fossils may represent a separate species, H. ergaster. To gain further resolution regarding this debate, 3D geometric morphometric data were used to quantify overall shape variation in the cranial vault within H.

Karen L. Baab

2008-01-01

7

Latest Homo erectus of Java: Potential Contemporaneity with Homo sapiens in Southeast Asia  

Microsoft Academic Search

Hominid fossils from Ngandong and Sambungmacan, Central Java, are considered the most morphologically advanced representatives of Homo erectus. Electron spin resonance (ESR) and mass spectrometric U-series dating of fossil bovid teeth collected from the hominid-bearing levels at these sites gave mean ages of 27 ± 2 to 53.3 ± 4 thousand years ago; the range in ages reflects uncertainties in

C. C. Swisher III; W. J. Rink; S. C. Anton; H. P. Schwarcz; G. H. Curtis; A. Suprijo; Widiasmoro

1996-01-01

8

Femoral\\/humeral strength in early African Homo erectus  

Microsoft Academic Search

Lower-to-upper limb-bone proportions give valuable clues to locomotor behavior in fossil taxa. However, to date only external linear dimensions have been included in such analyses of early hominins. In this study, cross-sectional measures of femoral and humeral diaphyseal strength are determined for the two most complete early Homo erectus (or ergaster) associated skeletons—the juvenile KNM-WT 15000 and the adult KNM-ER

Christopher Ruff

2008-01-01

9

Three new Homo erectus mandibles from Java  

Microsoft Academic Search

There are now eleven manidublar pieces from the Lower and Middle Pleistocene of Java, all but one being from the Sangiran\\u000a site. All of these have been assigned toHomo erectus by most workers, while others have suggested as many as four different hominoid taxa. Sangiran 21 (Mandible E), Sangiran\\u000a 22 (Mandible F), and Sangiran 37 (Mandible G) are described here

D. E. Tyler

2001-01-01

10

A Female Homo erectus Pelvis from Gona, Ethiopia  

Microsoft Academic Search

Analyses of the KNM-WT 15000 Homo erectus juvenile male partial skeleton from Kenya concluded that this species had a tall thin body shape due to specialized locomotor and climatic adaptations. Moreover, it was concluded that H. erectus pelves were obstetrically restricted to birthing a small-brained altricial neonate. Here we describe a nearly complete early Pleistocene adult female H. erectus pelvis

Scott W. Simpson; Jay Quade; Naomi E. Levin; Robert Butler; Guillaume Dupont-Nivet; Melanie Everett; Sileshi Semaw

2008-01-01

11

Gamma-ray spectrometric dating of late Homo erectus skulls from Ngandong and Sambungmacan, Central Java, Indonesia  

Microsoft Academic Search

Hominid fossils from Ngandong and Sambungmacan, Central Java, Indonesia, are considered to be the most anatomically derived and youngest representatives of Homo erectus. Nondestructive gamma-ray spectrometric dating of three of these Homo erectus skulls showed that all samples underwent uranium leaching. Nevertheless, we could establish minimum age estimates of around 40ka, with an upper age limit of around 60 to

Yuji Yokoyama; Christophe Falguères; François Sémah; Teuku Jacob; Rainer Grün

2008-01-01

12

African Homo erectus: Old Radiometric Ages and Young Oldowan Assemblages in the Middle Awash Valley, Ethiopia  

Microsoft Academic Search

Fossils and artifacts recovered from the middle Awash Valley of Ethiopia's Afar depression sample the Middle Pleistocene transition from Homo erectus to Homo sapiens. Ar\\/Ar ages, biostratigraphy, and tephrachronology from this area indicate that the Pleistocene Bodo hominid cranium and newer specimens are approximately 0.6 million years old. Only Oldowan chopper and flake assemblages are present in the lower stratigraphic

J. D. Clark; J. de Heinzelin; K. D. Schick; W. K. Hart; T. D. White; G. Woldegabriel; R. C. Walter; G. Suwa; B. Asfaw; E. Vrba; Y. H.-Selassie

1994-01-01

13

Cranial base morphology and temporal bone pneumatization in Asian Homo erectus  

Microsoft Academic Search

The external morphological features of the temporal bone are used frequently to determine taxonomic affinities of fossils of the genus Homo. Temporal bone pneumatization has been widely studied in great apes and in early hominids. However, this feature is rarely examined in the later hominids, particularly in Asian Homo erectus. We provide a comparative morphological and quantitative analysis of Asian

Antoine Balzeau; Dominique Grimaud-Hervé

2006-01-01

14

ESR dating of tooth enamel from yunxian homo erectus site, China  

Microsoft Academic Search

Two almost complete fossil hominid crania (EV9001 and EV9002) were found in 1989 and 1990 in Middle Pleistocene terrace deposit of Han River, Yunxian county, Hubei province, China. They are classified as Homo erectus. Nine fossil animal teeth stratigraphically associated with the skulls were selected for electron spin resonance (ESR) dating. The simple exponential function was used for determination of

Tie-Mei Chen; Quan Yang; Yan-Qiu Hu; Wen-Bo Bao; Tian-Yuan Li

1997-01-01

15

Structures crâniennes internes de l’ Homo erectus Sambungmacan 1 (Java, Indonésie)  

Microsoft Academic Search

The Sambungmacan 1 fossil (Java, Indonesia) is assigned to the Homo erectus group. The carbonated matrix contained in this calvaria prevents the analysis of the internal surface. The CT data of the original fossil enables us to observe the conservation and mineralization state and the internal structures. Furthermore, we use the CT data to reconstruct the endocast, which shows that

Antoine Balzeau; Teuku Jacob; Etty Indriati

2002-01-01

16

Remains of Homo erectus from Bouri, Middle Awash, Ethiopia  

Microsoft Academic Search

The genesis, evolution and fate of Homo erectus have been explored palaeontologically since the taxon's recognition in the late nineteenth century. Current debate is focused on whether early representatives from Kenya and Georgia should be classified as a separate ancestral species (`H. ergaster'), and whether H. erectus was an exclusively Asian species lineage that went extinct. Lack of resolution of

Berhane Asfaw; W. Henry Gilbert; Yonas Beyene; William K. Hart; Paul R. Renne; Giday WoldeGabriel; Elisabeth S. Vrba; Tim D. White

2002-01-01

17

Variation and diversity in Homo erectus: a 3D geometric morphometric analysis of the temporal bone  

Microsoft Academic Search

Although the level of taxonomic diversity within the fossil hominin species Homo erectus (sensu lato) is continually debated, there have been relatively few studies aiming to quantify the morphology of this species. Instead, most researchers have relied on qualitative descriptions or the evaluation of nonmetric characters, which in many cases display continuous variation. Also, only a few studies have used

Claire E. Terhune; William H. Kimbel; Charles A. Lockwood

2007-01-01

18

Mapping and taphonomic analysis of the Homo erectus loci at Locality 1 Zhoukoudian, China  

Microsoft Academic Search

From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on the grid. Meter cubes were used in excavation starting in 1934, and Loci H through O, established between 1934

Noel T. Boaz; Russell L. Ciochon; Qinqi Xu; Jinyi Liu

2004-01-01

19

A re-evaluation of the metric diversity within Homo erectus  

Microsoft Academic Search

Previous work by several researchers has suggested that the cranial sample from Zhoukoudian possesses a unique metric pattern relative to the African and Asian specimens assigned to Homo erectus. The current study readdresses this issue with an expanded fossil sample and a larger and more comprehensive set of cranial measurements. To test the patterns present in the assemblage, canonical variates

James H Kidder; Arthur C Durband

2004-01-01

20

Endocranial cast of Hexian Homo erectus from South China.  

PubMed

In this paper, we present data on the morphological features and linear measurements for the Hexian Homo erectus and other comparative endocasts, in order to highlight variation during human brain evolution. The endocast of Hexian was reconstructed in 1982, and an endocranial volume of 1,025 ml was estimated. The geological age is about 412 ka, or roughly contemporaneous with the Zhoukoudian (ZKD) specimens. There are some differences between Hexian and the modern Chinese male endocasts in our sample, including low position of the greatest breadth, low maximum height, a well-marked and prominent frontal keel, the flat surface of the frontal lobes, prominent sagittal keel along the center frontal and parietal lobes, depressed Sylvian areas and parietal lobes superiorly, strong posterior projection of the occipital lobes, anterior position of the cerebellar lobes relative to the occipital lobes, and the relative simplicity of the meningeal vessels. Compared with the ZKD, Indonesian, and African Homo erectus specimens, Hexian has more morphological features in common with ZKD. Principal component analyses indicate that Hexian is closest to the ZKD Homo erectus compared with the modern Chinese and other Homo erectus, but its great breadth distinguishes it. Metric analyses show that the brain height, frontal breadth, cerebral height, frontal height, and parietal chord from Homo erectus to modern humans increased, while the length, breadth, frontal chord, and occipital breadth did not change substantially. PMID:16425176

Wu, Xiujie; Schepartz, Lynne A; Falk, Dean; Liu, Wu

2006-08-01

21

A new Homo erectus cranium from Sangiran, Java  

Microsoft Academic Search

A newHomo erectus cranium was found on May 18, 1993 by Budi, a local farmer, at Sangiran. It dates from the Middle Pucangan Formation approximately\\u000a 1.6–1.8 mya. The braincase is essentially complete and as is most of the face. The vault has the typicalH. erectus gable shape. There is a clear sagittal ridge beginning below the middle of the frontal

D. E. Tyler; S. Sartono

2001-01-01

22

Neurocranial abnormalities of the Gongwangling Homo erectus from Lantian, China  

Microsoft Academic Search

The Homo erectus cranium found at Gongwangling, near Lantian, China, and dated to ?1.2ma BP has been analyzed with respect to its evolutionary position. However, the remains, and especially the internal and external surfaces of the neurocranium, present a series of marked abnormalities. These irregularities consist principally of a pronounced cresting and scalloping of the external surface of the frontal

Hong Shang; Erik Trinkaus; Wu Liu; Xinzhi Wu; Qizhi Zhu

2008-01-01

23

Endocranial cast of HexianHomo erectus from South China  

Microsoft Academic Search

In this paper, we present data on the morphological features and linear measurements for the Hexian Homo erectus and other comparative endocasts, in order to highlight variation during human brain evo- lution. The endocast of Hexian was reconstructed in 1982, and an endocranial volume of 1,025 ml was esti- mated. The geological age is about 412 ka, or roughly contemporaneous

Xiujie Wu; Lynne A. Schepartz; Dean Falk; Wu Liu

2006-01-01

24

Early Homo erectus skeleton from west Lake Turkana, Kenya.  

PubMed

The most complete early hominid skeleton ever found was discovered at Nariokotome III, west Lake Turkana, Kenya, and excavated in situ in sediments dated close to 1.6 Myr. The specimen, KNM-WT 15000, is a male Homo erectus that died at 12 +/- 1 years of age, as judged by human standards, but was already 1.68 m tall. Although human-like in many respects, this specimen documents important anatomical differences between H. erectus and modern humans for the first time. PMID:3929141

Brown, F; Harris, J; Leakey, R; Walker, A

25

Palaeolithic chronology and possible coexistence of Homo erectus and Homo sapiens in China  

Microsoft Academic Search

The dating results of twenty?five Chinese palaeolithic and palaeoanthropological sites are summarized. Palaeomagnetism, Uranium?series and radiocarbon are the three main dating techniques used in establishing the chronology. The paper discusses the reliability of dating results, correlation between climate and the age distribution of sites, and the possible coexistence of Homo erectus and Homo sapiens.

Chen Tiemei; Zhang Yinyun

1991-01-01

26

A new brain endocast of Homo erectus from Hulu Cave, Nanjing, China.  

PubMed

A new brain endocast of Homo erectus from Hulu Cave, Tangshan, Nanjing is described and compared with a broad sample of endocasts of H. erectus, Neanderthals, and recent modern humans. The Nanjing 1 endocast is reconstructed based on two portions of endocranial casts taken from the original fossil fragments. The fossil was discovered in 1993, near Nanjing, South China and is dated to ? 0.58-0.62 Ma. The cranial capacity is ? 876 cc, as determined by endocast water displacement. There are some common features of Nanjing 1 and other H. erectus endocasts that differentiate them from the Neanderthals and modern humans in our sample. These include small cranial capacity, low height dimensions, simple middle meningeal vessel patterns, a high degree of cerebral-over-cerebellar lobe overhang, elongated and quite separated cerebellar lobes, and a narrow, low, short and flat frontal region. Some features are found to vary among H. erectus, Neanderthals and modern humans, such as the lateral Sylvian fissure position and the venous sinus and petalial patterns. The Nanjing 1 endocast has unique, large, superior frontal convolutions, and strongly protruding Broca's caps. In contrast to other Chinese H. erectus from Hexian and Zhoukoudian, Nanjing 1 lacks strong posterior projection of the occipital lobes. Bivariate and principal component analyses indicate that the small volume and shape of Nanjing 1 is most similar to KNM-WT 15000, KNM-ER 3883, Sangiran 2 and Hexian, illustrating the combination of narrow, low, and short frontal lobes with wide posterior lobes. PMID:21541930

Wu, Xiujie; Holloway, Ralph L; Schepartz, Lynne A; Xing, Song

2011-05-03

27

Human taxonomic diversity in the pleistocene: does Homo erectus represent multiple hominid species?  

PubMed

Recently, nomina such as "Homo heidelbergensis" and "H. ergaster" have been resurrected to refer to fossil hominids that are perceived to be specifically distinct from Homo sapiens and Homo erectus. This results in a later human fossil record that is nearly as speciose as that documenting the earlier history of the family Hominidae. However, it is agreed that there remains only one extant hominid species: H. sapiens. Has human taxonomic diversity been significantly pruned over the last few hundred millennia, or have the number of taxa been seriously overestimated? To answer this question, the following null hypothesis is tested: polytypism was established relatively early and the species H. erectus can accommodate all spatio-temporal variation from ca. 1.7 to 0.5 Ma. A disproof of this hypothesis would suggest that modern human polytypism is a very recent phenomenon and that speciation throughout the course of human evolution was the norm and not the exception. Cranial variation in a taxonomically mixed sample of fossil hominids, and in a modern human sample, is analyzed with regard to the variation present in the fossils attributed to H. erectus. The data are examined using both univariate (coefficient of variation) and multivariate (determinant) analyses. Employing randomization methodology to offset the small size and non-normal distribution of the fossil samples, the CV and determinant results reveal a pattern and degree of variation in H. erectus that most closely approximates that of the single species H. sapiens. It is therefore concluded that the null hypothesis cannot be rejected. PMID:8317558

Kramer, A

1993-06-01

28

Early Homo erectus skeleton from west Lake Turkana, Kenya  

Microsoft Academic Search

The most complete early hominid skeleton ever found was discovered at Nariokotome III, west Lake Turkana, Kenya, and excavated in situ in sediments dated close to 1.6 Myr. The specimen, KNM-WT 15000, is a male Homo erectus that died at 12 +\\/- 1 years of age, as judged by human standards, but was already 1.68 m tall. Although human-like in

Frank Brown; John Harris; Richard Leakey; Alan Walker

1985-01-01

29

Sangiran 5, (“Pithecanthropus dubius”), homo erectus, “Meganthropus,” or Pongo?  

Microsoft Academic Search

There are now eleven known mandibular remains from the Lower and Middle Pleistocene of Java, all but one being from the Sangiran\\u000a site. All of these have been assigned toHomo erectus by most workers, while others have suggested as many as four different hominoid taxa. The author finds that the jaws cannot\\u000a be a homogeneous sample. Morphologically, they are a

D. E. Tyler

2003-01-01

30

African Homo erectus: Old radiometric ages and young Oldowan assemblages in the middle Awash Valley, Ethiopia  

SciTech Connect

Fossils and artifacts recovered from the middle Awash Valley of Ethiopia's Afar depression sample the Middle Pleistocene transition from Homo erectus to Homo sapiens. Ar/Ar ages, biostratigraphy, and tephrachronology from this area indicate that the Pleistocene Bodo hominid cranium and newer specimens are approximately 0.6 million years old. Only Oldowan chopper and flake assemblages are present in the lower stratigraphic units but Acheulean bifacial artifacts are consistently prevalent and widespread in directly overlying deposits. This technological transition is related to a shift in sedimentary regime, supporting the hypothesis that Middle Pleistocene Oldowan assemblages represent a behavioral facies of the Acheulean industrial complex.

Clark, J.D.; White, T.D.; Selassie, Y.H. (Univ. of California, Berkeley, CA (United States)); Heinzelin, J. de (Institut Royal des Sciences Naturelles de Belgique, Brussels (Belgium)); Schick, K.D. (Indiana Univ., Bloomington, IN (United States)); Hart, W.K. (Miami Univ., Oxford, OH (United States)); WoldeGabriel, G. (Los Alamos National Lab., NM (United States)); Walter, R.C. (Institute of Human Origins, Berkeley, CA (United States)); Suwa, G. (Univ. of Tokyo (Japan)); Asfaw, B. (Addis Ababa (Ethiopia)) (and others)

1994-06-24

31

African Homo erectus: old radiometric ages and young Oldowan assemblages in the Middle Awash Valley, Ethiopia.  

PubMed

Fossils and artifacts recovered from the middle Awash Valley of Ethiopia's Afar depression sample the Middle Pleistocene transition from Homo erectus to Homo sapiens. Ar/Ar ages, biostratigraphy, and tephrachronology from this area indicate that the Pleistocene Bodo hominid cranium and newer specimens are approximately 0.6 million years old. Only Oldowan chopper and flake assemblages are present in the lower stratigraphic units, but Acheulean bifacial artifacts are consistently prevalent and widespread in directly overlying deposits. This technological transition is related to a shift in sedimentary regime, supporting the hypothesis that Middle Pleistocene Oldowan assemblages represent a behavioral facies of the Acheulean industrial complex. PMID:8009220

Clark, J D; de Heinzelin, J; Schick, K D; Hart, W K; White, T D; WoldeGabriel, G; Walter, R C; Suwa, G; Asfaw, B; Vrba, E

1994-06-24

32

Solo man in question: Convergent views to split Indonesian Homo erectus in two categories  

Microsoft Academic Search

Between the famous Man of Java and the new star of paleoanthropology id est the Man of Flores, embedded in the bank of the river Solo or in the shadow of the volcanoes of Sangiran, Homo erectus remains apart. Driven from evolved Homo erectus to archaic Homo sapiens, for a long time Solo man did not find a real place

Valery Zeitoun; Florent Détroit; Dominique Grimaud-Hervé; Harry Widianto

2010-01-01

33

Grandmothering and the evolution of Homo erectus  

Microsoft Academic Search

Despite recent, compelling challenge, the evolution ofHomo erectusis still commonly attributed to big game hunting and\\/or scavenging and family provisioning by men. Here we use a version of the “grandmother” hypothesis to develop an alternative scenario, that climate-driven adjustments infemaleforaging and food sharing practices, possibly involving tubers, favored significant changes in ancestral life history, morphology, and ecology leading to the

J. F. O’Connell; K. Hawkes; N. G. Blurton Jones

1999-01-01

34

An examination of the taxonomic status of the fragmentary mandible Sangiran 5, ( Pithecanthropus dubius), Homo erectus, “ Meganthropus”, or Pongo?  

Microsoft Academic Search

There are 12 known mandibular fossils from the Lower and Middle Pleistocene of Java, all but two from the Sangiran Dome region. All of these have been assigned at various times to Homo erectus, but the same specimens have been said by others to represent as many as four different hominoid taxa. This is not, however, the finding of this

D. E. Tyler

2004-01-01

35

A new Homo erectus (Zhoukoudian V) brain endocast from China.  

PubMed

A new Homo erectus endocast, Zhoukoudian (ZKD) V, is assessed by comparing it with ZKD II, ZKD III, ZKD X, ZKD XI, ZKD XII, Hexian, Trinil II, Sambungmacan (Sm) 3, Sangiran 2, Sangiran 17, KNM-ER 3733, KNM-WT 15 000, Kabwe, Liujiang and 31 modern Chinese. The endocast of ZKD V has an estimated endocranial volume of 1140 ml. As the geological age of ZKD V is younger than the other ZKD H. erectus, evolutionary changes in brain morphology are evaluated. The brain size of the ZKD specimens increases slightly over time. Compared with the other ZKD endocasts, ZKD V shows important differences, including broader frontal and occipital lobes, some indication of fuller parietal lobes, and relatively large brain size that reflect significant trends documented in later hominin brain evolution. Bivariate and principal component analyses indicate that geographical variation does not characterize the ZKD, African and other Asian specimens. The ZKD endocasts share some common morphological and morphometric features with other H. erectus endocasts that distinguish them from Homo sapiens. PMID:19403532

Wu, Xiujie; Schepartz, Lynne A; Liu, Wu

2009-04-29

36

A new Homo erectus (Zhoukoudian V) brain endocast from China  

PubMed Central

A new Homo erectus endocast, Zhoukoudian (ZKD) V, is assessed by comparing it with ZKD II, ZKD III, ZKD X, ZKD XI, ZKD XII, Hexian, Trinil II, Sambungmacan (Sm) 3, Sangiran 2, Sangiran 17, KNM-ER 3733, KNM-WT 15?000, Kabwe, Liujiang and 31 modern Chinese. The endocast of ZKD V has an estimated endocranial volume of 1140?ml. As the geological age of ZKD V is younger than the other ZKD H. erectus, evolutionary changes in brain morphology are evaluated. The brain size of the ZKD specimens increases slightly over time. Compared with the other ZKD endocasts, ZKD V shows important differences, including broader frontal and occipital lobes, some indication of fuller parietal lobes, and relatively large brain size that reflect significant trends documented in later hominin brain evolution. Bivariate and principal component analyses indicate that geographical variation does not characterize the ZKD, African and other Asian specimens. The ZKD endocasts share some common morphological and morphometric features with other H. erectus endocasts that distinguish them from Homo sapiens.

Wu, Xiujie; Schepartz, Lynne A.; Liu, Wu

2010-01-01

37

Structural analysis of the Kresna 11 Homo erectus femoral shaft (Sangiran, Java).  

PubMed

The biomechanical characterization of lower limb long bones in the chrono-ecogeographically diverse species Homo erectus is a fundamental step for assessing evolutionary changes in locomotor mode and body shape that occurred within the genus Homo. However, the samples available for the Early and earlier Middle Pleistocene are small and widely scattered in time and space, thus limiting our understanding of the nature and polarity of morphological trends. Compared to the African fossil record, loading histories based on detailed biomechanical assessment of diaphyseal strength in Indonesian H. erectus lower limb long bones have not been assessed. By using a microtomographic record (?CT), we performed a quantitative analysis of the biomechanical properties and structural organization of Kresna 11, a late Early Pleistocene adult H. erectus femoral shaft from the Sangiran Dome, Central Java. Relative to the modern human condition, Kresna 11 shows the predominant mediolateral cortical thickening (hypertrophy) and the distal displacement of the minimum diaphyseal breadth characteristic of early Homo femora, associated nonetheless with relatively modest cortical thickness within the mid-proximal portion. Synthetic functional imaging of the shaft through the planar representation of its inner structure has revealed distal thickening of the medial cortex, a feature previously unreported in H. erectus. The increase in relative mediolateral bending strength observed in Kresna 11 supports the hypothesis that, rather than simply reflecting differences in patterns of locomotor loading, biomechanical properties of the femoral shaft in archaic Homo are strongly influenced by body shape, i.e., variations in pelvic breadth and femoral neck length. PMID:23036460

Puymerail, Laurent; Ruff, Christopher B; Bondioli, Luca; Widianto, Harry; Trinkaus, Erik; Macchiarelli, Roberto

2012-10-01

38

Cranial morphology of Javanese Homo erectus: new evidence for continuous evolution, specialization, and terminal extinction.  

PubMed

Our current knowledge of the evolution of Homo during the early to middle Pleistocene is far from complete. This is not only because of the small number of fossil samples available, but also due to the scarcity of standardized datasets which are reliable in terms of landmark identification, interobserver error, and other distorting factors. This study aims to accurately describe the cranial morphological changes of H. erectus in Java using a standardized set of measurements taken by the authors from 18 adult crania from Sangiran, Trinil, Sambungmacan, and Ngandong. The identification of some obscure landmarks was aided by the use of micro-CT imaging. While recent studies tend to emphasize evolutionary conservatism in Javanese H. erectus, our results reinforce the theory that chronologically later groups experienced distinct morphological changes in a number of cranial traits. Some of these changes, particularly those related to brain size expansion, are similar to those observed for the genus Homo as a whole, whereas others are apparently unique specializations restricted to Javanese H. erectus. Such morphological specializations in Java include previously undescribed anteroposterior lengthening of the midcranial base and an anterior shift of the posterior temporal muscle, which might have influenced the morphology of the angular torus and supramastoid sulcus. Analyses of morphological variation indicate that the three crania from Sambungmacan variously fill the morphological gap between the chronologically earlier (Bapang-AG, Bapang Formation above the Grenzbank zone in Sangiran) and later (Ngandong) morphotypes of Java. At least one of the Bapang-AG crania, Sangiran 17, also exhibits a few characteristics which potentially indicate evolution toward the Ngandong condition. These strongly suggest the continuous, gradual morphological evolution of Javanese H. erectus from the Bapang-AG to Ngandong periods. The development of some unique features in later Javanese H. erectus supports the hypothesis that this Javanese lineage went extinct without making significant contributions to the ancestry of modern humans. PMID:18635247

Kaifu, Yousuke; Aziz, Fachroel; Indriati, Etty; Jacob, Teuku; Kurniawan, Iwan; Baba, Hisao

2008-07-16

39

Proposition de reconstitution du deuxième crâne d’ Homo erectus de Yunxian (Chine)  

Microsoft Academic Search

A proposal of reconstruction of the second Homo erectus skull from Yunxian (China). In 1989 and 1990, two Homo erectus crania were recovered from Yunxian (Hubei province) in archaeological levels dated to more than 780?000 years. Considered along with Lantian, these skulls represent the oldest human remains discovered in China to date, constituting important palaeontological finds. Nevertheless, the crania were

Amélie Vialet; Tianyuan Li; Dominique Grimaud-Hervé; Marie-Antoinette de Lumley; Meiyan Liao; Xiaobo Feng

2005-01-01

40

Age of Zhoukoudian Homo erectus determined with 26Al\\/10Be burial dating  

Microsoft Academic Search

The age of Zhoukoudian Homo erectus, commonly known as `Peking Man', has long been pursued, but has remained problematic owing to the lack of suitable dating methods. Here we report cosmogenic 26Al\\/10Be burial dating of quartz sediments and artefacts from the lower strata of Locality 1 in the southwestern suburb of Beijing, China, where early representatives of Zhoukoudian Homo erectus

Guanjun Shen; Xing Gao; Bin Gao; Darryl E. Granger

2009-01-01

41

Dated co-occurrence of Homo erectus and Gigantopithecus from Tham Khuyen Cave, Vietnam.  

PubMed Central

Tham Khuyen Cave (Lang Son Province, northern Vietnam) is one of the more significant sites to yield fossil vertebrates in east Asia. During the mid-1960s, excavation in a suite of deposits produced important hominoid dental remains of middle Pleistocene age. We undertake more rigorous analyses of these sediments to understand the fluvial dynamics of Pleistocene cave infilling as they determine how skeletal elements accumulate within Tham Khuyen and other east Asian sites. Uranium/thorium series analysis of speleothems brackets the Pleistocene chronology for breaching, infilling, and exhuming the regional paleokarst. Clast analysis indicates sedimentary constituents, including hominoid teeth and cranial fragments accumulated from very short distances and under low fluvial energy. Electron spin resonance analysis of vertebrate tooth enamel and sediments shows that the main fossil-bearing suite (S1-S3) was deposited about 475 thousand years ago. Among the hominoid teeth excavated from S1-S3, some represent Homo erectus and Gigantopithecus blacki. Criteria are defined to differentiate these teeth from more numerous Pongo pygmaeus elements. The dated co-occurrence of Homo erectus and Gigantopithecus blacki at Tham Khuyen helps to establish the long co-existence of these two species throughout east Asia during the Early and Middle Pleistocene. Images Fig. 1 Fig. 2

Ciochon, R; Long, V T; Larick, R; Gonzalez, L; Grun, R; de Vos, J; Yonge, C; Taylor, L; Yoshida, H; Reagan, M

1996-01-01

42

New reconstruction and morphological description of a Homo erectus cranium: skull IX (Tjg-1993.05) from Sangiran, Central Java.  

PubMed

Skull IX (Tjg-1993.05) was unearthed from the upper stratigraphic zone (Bapang-AG levels) of the hominin-bearing sequence in Sangiran. This remarkably complete cranial specimen of Homo erectus from the early Pleistocene of Java preserves substantial portions of the vault and face. However, the distortion present in the original reconstruction has hampered detailed documentation of its morphological characteristics. We here report a new reconstruction of Skull IX that successfully recovers the original morphology and significantly differs from previous reconstructions. Detailed morphological description and the results of initial comparative analyses based on this new reconstruction are provided. The endocranial volume of Skull IX was measured as 870 cc using micro-CT data. The neurocranium of Skull IX is slightly smaller than the so far recorded smallest cranium from this zone, suggesting this individual was female. In most, but not all, aspects of the cranial vault form, details of the external surface structures, and facial morphology, Skull IX exhibits numerous similarities to the other Bapang-AG H. erectus specimens, indicating that it belonged to the Bapang-AG H. erectus population. Drawing on the expanded fossil sample of this chronoregional H. erectus group, we discuss their evolutionary status, degree of sexual dimorphism, and facial morphological variation in Afro-Asian earlier Homo specimens. PMID:21683428

Kaifu, Yousuke; Zaim, Yahdi; Baba, Hisao; Kurniawan, Iwan; Kubo, Daisuke; Rizal, Yan; Arif, Johan; Aziz, Fachroel

2011-06-17

43

Mojokerto revisited: evidence for an intermediate pattern of brain growth in Homo erectus.  

PubMed

Brain development in Homo erectus is a subject of great interest, and the infant calvaria from Mojokerto, Indonesia, has featured prominently in these debates. Some researchers have suggested that the pattern of brain development in H. erectus resembled that of non-human apes, while others argue for a more human-like growth pattern. In this study, we retested hypotheses regarding brain ontogeny in H. erectus using new methods (resampling), and data from additional H. erectus crania. Our results reveal that humans achieve 62% (±10%) and chimpanzees 80% (±9%) of their adult endocranial volume by 0.5-1.5 years of age. Using brain mass data, humans achieve on average 65% and chimpanzees 81% of adult size by 0.5-1.5 years. When compared with adult H. erectus crania (n = 9) from Indonesian sites greater than 1.2 million years old, Mojokerto had reached ?70% of its adult cranial capacity. Mojokerto thus falls almost directly between the average growth in humans and chimpanzees, and well within the range of both. We therefore suggest that brain development in H. erectus cannot be dichotomized as either ape-like or human-like; it was H. erectus-like. These data indicate that H. erectus may have had a unique developmental pattern that should be considered as an important step along the continuum of brain ontogeny between apes and humans. PMID:23815827

O'Connell, Caitlin A; DeSilva, Jeremy M

2013-06-28

44

First Homo erectus from Turkey and implications for migrations into temperate Eurasia.  

PubMed

Remains of fossil hominins from temperate regions of the Old World are rare across both time and space, but such specimens are necessary for understanding basic issues in human evolution including linkages between their adaptations and early migration patterns. We report here the remarkable circumstances surrounding the discovery of the first fossil hominin calvaria from Turkey. The specimen was found in the Denizli province of western Turkey and recovered from within a solid block of travertine stone as it was being sawed into tile-sized slabs for the commercial natural stone building market. The new specimen fills an important geographical and temporal gap and displays several anatomical features that are shared with other Middle Pleistocene hominins from both Africa and Asia attributed to Homo erectus. It also preserves an unusual pathology on the endocranial surface of the frontal bone that is consistent with a diagnosis of Leptomeningitis tuberculosa (TB), and this evidence represents the most ancient example of this disease known for a fossil human. TB is exacerbated in dark-skinned peoples living in northern latitudes by a vitamin D deficiency because of reduced levels of ultraviolet radiation (UVR). Evidence for TB in the new specimen supports the thesis that reduced UVR was one of the many climatic variables presenting an adaptive challenge to ancient hominins during their migration into the temperate regions of Europe and Asia. PMID:18067194

Kappelman, John; Alçiçek, Mehmet Cihat; Kazanci, Nizamettin; Schultz, Michael; Ozkul, Mehmet; Sen, Sevket

2008-01-01

45

No skeletal dysplasia in the Nariokotome boy KNM-WT 15000 (Homo erectus)--a reassessment of congenital pathologies of the vertebral column.  

PubMed

The Nariokotome boy skeleton KNM-WT 15000 is the most complete Homo erectus fossil and therefore is key for understanding human evolution. Nevertheless, since Latimer and Ohman (2001) reported on severe congenital pathology in KNM-WT 15000, it is questionable whether this skeleton can still be used as reference for Homo erectus skeletal biology. The asserted pathologies include platyspondylic and diminutive vertebrae implying a disproportionately short stature; spina bifida; condylus tertius; spinal stenosis; and scoliosis. Based on this symptom complex, the differential diagnosis of spondyloepiphyseal dysplasia tarda, an extremely rare form of skeletal dysplasia, has been proposed. Yet, our reanalysis of these pathologies shows that the shape of the KNM-WT 15000 vertebrae matches that of normal modern human adolescents. The vertebrae are not abnormally flat, show no endplate irregularities, and thus are not platyspondylic. As this is the hallmark of spondyloepiphyseal dysplasia tarda and related forms of skeletal dysplasia, the absence of platyspondyly refutes axial dysplasia and disproportionate dwarfism. Furthermore, we neither found evidence for spina bifida occulta nor manifesta, whereas the condylus tertius, a developmental anomaly of the cranial base, is not related to skeletal dysplasias. Other fossils indicate that the relatively small size of the vertebrae and the narrow spinal canal are characteristics of early hominins rather than congenital pathologies. Except for the recently described signs of traumatic lumbar disc herniation, the Nariokotome boy fossil therefore seems to belong to a normal Homo erectus youth without pathologies of the axial skeleton. PMID:23283736

Schiess, Regula; Haeusler, Martin

2013-01-03

46

Early brain growth in Homo erectus and implications for cognitive ability  

Microsoft Academic Search

Humans differ from other primates in their significantly lengthened growth period. The persistence of a fetal pattern of brain growth after birth is another important feature of human development. Here we present the results of an analysis of the 1.8-million-year-old Mojokerto child (Perning 1, Java), the only well preserved skull of a Homo erectus infant, by computed tomography. Comparison with

H. Coqueugniot; J.-J. Hublin; F. Veillon; F. Houët; T. Jacob

2004-01-01

47

Way out of Africa: Early Pleistocene paleoenvironments inhabited by Homo erectus in Sangiran, Java  

Microsoft Academic Search

A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regional environments present when Homo erectus spread through Southeast Asia during the early Pleistocene. The earliest human immigrants encountered a low-relief lake-margin landscape dominated by moist grasslands with open woodlands in the driest landscape positions. By 1.5Ma, large streams filled the lake and the landscape

E. Arthur Bettis; Adrianne K. Milius; Scott J. Carpenter; Roy Larick; Yahdi Zaim; Yan Rizal; Russell L. Ciochon; Stephanie A. Tassier-Surine; Daniel Murray; Suminto; Sutinko Bronto

2009-01-01

48

Homo erectus and Middle Pleistocene hominins: brain size, skull form, and species recognition.  

PubMed

Hominins that differ from Homo erectus, the Neanderthals, and recent humans are known from Middle Pleistocene localities across the Old World. The taxonomic status of these populations has been clouded by controversy. Perhaps the most critical problem has been an incomplete understanding of variation in skull form. Here, both H. erectus and later mid-Pleistocene hominins are the focus of an investigation aimed at clarifying the relationships among brain volume, basicranial dimensions, neurocranial shape, and certain facial characters. Brain size in H. erectus averages about 950 cm(3), while in a series of Middle Pleistocene crania from Africa and Europe, volume is about 1230 cm(3). If encephalization is the primary mechanism operating in the mid-Pleistocene, then diverse aspects of cranial form cannot all be treated as independent variables. Correlation is utilized to examine the associations among measurements for more than 30 H. erectus crania that are reasonably well preserved. A similar approach is used with the Middle Pleistocene sample. Patterns of covariation are compared in order to assess integration. Next, factor analysis is applied to the H. erectus specimens in an attempt to identify modules, tightly integrated traits that can evolve independently. Studies of the variation within H. erectus are followed by direct comparisons with the Middle Pleistocene population. Discriminant functions facilitate the description of intergroup differences. Traits that vary independently from brain volume include anterior frontal broadening, lateral expansion of the parietal vault, elevation of the lambda-inion chord, and rounding of the sagittal contour of the occipital. This finding helps to resolve the problem of species recognition. Neurocranial proportions as well as characters from the cranial base and face can be incorporated into a differential diagnosis for the mid-Pleistocene sample. Evidence presented here supports arguments for speciation in the Middle Pleistocene. PMID:23850294

Rightmire, G Philip

2013-07-10

49

Hominid mandibular corpus shape variation and its utility for recognizing species diversity within fossil Homo  

PubMed Central

Mandibular corpora are well represented in the hominin fossil record, yet few studies have rigorously assessed the utility of mandibular corpus morphology for species recognition, particularly with respect to the linear dimensions that are most commonly available. In this study, we explored the extent to which commonly preserved mandibular corpus morphology can be used to: (i) discriminate among extant hominid taxa and (ii) support species designations among fossil specimens assigned to the genus Homo. In the first part of the study, discriminant analysis was used to test for significant differences in mandibular corpus shape at different taxonomic levels (genus, species and subspecies) among extant hominid taxa (i.e. Homo, Pan, Gorilla, Pongo). In the second part of the study, we examined shape variation among fossil mandibles assigned to Homo(including H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster, late African H. erectus, Asian H. erectus, H. heidelbergensis, H. neanderthalensis and H. sapiens). A novel randomization procedure designed for small samples (and using group ‘distinctness values’) was used to determine whether shape variation among the fossils is consistent with conventional taxonomy (or alternatively, whether a priori taxonomic groupings are completely random with respect to mandibular morphology). The randomization of ‘distinctness values’ was also used on the extant samples to assess the ability of the test to recognize known taxa. The discriminant analysis results demonstrated that, even for a relatively modest set of traditional mandibular corpus measurements, we can detect significant differences among extant hominids at the genus and species levels, and, in some cases, also at the subspecies level. Although the randomization of ‘distinctness values’ test is more conservative than discriminant analysis (based on comparisons with extant specimens), we were able to detect at least four distinct groups among the fossil specimens (i.e. H. sapiens, H. heidelbergensis, Asian H. erectus and a combined ‘African Homo’ group consisting of H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster and late African H. erectus). These four groups appear to be distinct at a level similar to, or greater than, that of modern hominid species. In addition, the mandibular corpora of H. neanderthalensis could be distinguished from those of ‘African Homo’, although not from those of H. sapiens, H. heidelbergensis, or the Asian H. erectus group. The results suggest that the features most commonly preserved on the hominin mandibular corpus have some taxonomic utility, although they are unlikely to be useful in generating a reliable alpha taxonomy for early African members of the genus Homo.

Lague, Michael R; Collard, Nicole J; Richmond, Brian G; Wood, Bernard A

2008-01-01

50

A calvarium of late Homo erectus from Ceprano, Italy  

Microsoft Academic Search

On 13 March 1994, a fragmented, incomplete and highly fossilized, human calvarium was discoveredin situby one of the authors (I.B.) during excavations for the construction of a highway near Ceprano, a town in southern Latium, situated about 55 miles S.E. from Rome. The remains come from a clay lying below sandy volcaniclastic gravels whose age is estimated by K–Ar to

A. Ascenzi; I. Biddittu; P. F. Cassoli; A. G. Segre; E. Segre-Naldini

1996-01-01

51

Growth processes in teeth distinguish modern humans from Homo erectus and earlier hominins  

Microsoft Academic Search

A modern human-like sequence of dental development, as a proxy for the pace of life history, is regarded as one of the diagnostic hallmarks of our own genus Homo. Brain size, age at first reproduction, lifespan and other life-history traits correlate tightly with dental development. Here we report differences in enamel growth that show the earliest fossils attributed to Homo

Christopher Dean; Meave G. Leakey; Donald Reid; Friedemann Schrenk; Gary T. Schwartz; Christopher Stringer; Alan Walker

2001-01-01

52

Age of Zhoukoudian Homo erectus determined with (26)Al/(10)Be burial dating.  

PubMed

The age of Zhoukoudian Homo erectus, commonly known as 'Peking Man', has long been pursued, but has remained problematic owing to the lack of suitable dating methods. Here we report cosmogenic (26)Al/(10)Be burial dating of quartz sediments and artefacts from the lower strata of Locality 1 in the southwestern suburb of Beijing, China, where early representatives of Zhoukoudian Homo erectus were discovered. This study marks the first radioisotopic dating of any early hominin site in China beyond the range of mass spectrometric U-series dating. The weighted mean of six meaningful age measurements, 0.77 +/- 0.08 million years (Myr, mean +/- s.e.m.), provides the best age estimate for lower cultural layers 7-10. Together with previously reported U-series dating of speleothem calcite and palaeomagnetic stratigraphy, as well as sedimentological considerations, these layers may be further correlated to S6-S7 in Chinese loess stratigraphy or marine isotope stages (MIS) 17-19, in the range of approximately 0.68 to 0.78 Myr ago. These ages are substantially older than previously supposed and may imply early hominin's presence at the site in northern China through a relatively mild glacial period corresponding to MIS 18. PMID:19279636

Shen, Guanjun; Gao, Xing; Gao, Bin; Granger, Darryl E

2009-03-12

53

Homo erectus in East and Southeast Asia, and the questions of the age of the species and its association with stone artifacts, with special attention to handaxe-like tools  

Microsoft Academic Search

Homo ergaster\\/Homo erectus in Africa and H. erectus in the Old World are securely associated with a toolkit of well-conceived bifacially worked implements of handaxes and cleavers of the Acheulean techno-complex. In India, the abundant handaxe–cleaver assemblages have always been attributed as the work of H. erectus on the basis of comparisons with Africa and the Old World. In 1982,

Gudrun Corvinus

2004-01-01

54

High-resolution record of the Matuyama-Brunhes transition constrains the age of Javanese Homo erectus in the Sangiran dome, Indonesia  

PubMed Central

A detailed paleomagnetic study conducted in the Sangiran area, Java, has provided a reliable age constraint on hominid fossil-bearing formations. A reverse-to-normal polarity transition marks a 7-m thick section across the Upper Tuff in the Bapang Formation. The transition has three short reversal episodes and is overlain by a thick normal polarity magnetozone that was fission-track dated to the Brunhes chron. This pattern closely resembles another high-resolution Matuyama–Brunhes (MB) transition record in an Osaka Bay marine core. In the Sangiran sediments, four successive transitional polarity fields lie just below the presumed main MB boundary. Their virtual geomagnetic poles cluster in the western South Pacific, partly overlapping the transitional virtual geomagnetic poles from Hawaiian and Canary Islands’ lavas, which have a mean 40Ar/39Ar age of 776 ± 2 ka. Thus, the polarity transition is unambiguously the MB boundary. A revised correlation of tuff layers in the Bapang Formation reveals that the hominid last occurrence and the tektite level in the Sangiran area are nearly coincident, just below the Upper Middle Tuff, which underlies the MB transition. The stratigraphic relationship of the tektite level to the MB transition in the Sangiran area is consistent with deep-sea core data that show that the meteorite impact preceded the MB reversal by about 12 ka. The MB boundary currently defines the uppermost horizon yielding Homo erectus fossils in the Sangiran area.

Hyodo, Masayuki; Matsu'ura, Shuji; Kamishima, Yuko; Kondo, Megumi; Takeshita, Yoshihiro; Kitaba, Ikuko; Danhara, Tohru; Aziz, Fachroel; Kurniawan, Iwan; Kumai, Hisao

2011-01-01

55

The Age of the 20 Meter Solo River Terrace, Java, Indonesia and the Survival of Homo erectus in Asia  

PubMed Central

Homo erectus was the first human lineage to disperse widely throughout the Old World, the only hominin in Asia through much of the Pleistocene, and was likely ancestral to H. sapiens. The demise of this taxon remains obscure because of uncertainties regarding the geological age of its youngest populations. In 1996, some of us co-published electron spin resonance (ESR) and uranium series (U-series) results indicating an age as young as 35–50 ka for the late H. erectus sites of Ngandong and Sambungmacan and the faunal site of Jigar (Indonesia). If correct, these ages favor an African origin for recent humans who would overlap with H. erectus in time and space. Here, we report 40Ar/39Ar incremental heating analyses and new ESR/U-series age estimates from the “20 m terrace" at Ngandong and Jigar. Both data sets are internally consistent and provide no evidence for reworking, yet they are inconsistent with one another. The 40Ar/39Ar analyses give an average age of 546±12 ka (sd±5 se) for both sites, the first reliable radiometric indications of a middle Pleistocene component for the terrace. Given the technical accuracy and consistency of the analyses, the argon ages represent either the actual age or the maximum age for the terrace and are significantly older than previous estimates. Most of the ESR/U-series results are older as well, but the oldest that meets all modeling criteria is 143 ka+20/?17. Most samples indicated leaching of uranium and likely represent either the actual or the minimum age of the terrace. Given known sources of error, the U-series results could be consistent with a middle Pleistocene age. However, the ESR and 40Ar/39Ar ages preclude one another. Regardless, the age of the sites and hominins is at least bracketed between these estimates and is older than currently accepted.

Indriati, Etty; Swisher, Carl C.; Lepre, Christopher; Quinn, Rhonda L.; Suriyanto, Rusyad A.; Hascaryo, Agus T.; Grun, Rainer; Feibel, Craig S.; Pobiner, Briana L.; Aubert, Maxime; Lees, Wendy; Anton, Susan C.

2011-01-01

56

The age of the 20 meter Solo River terrace, Java, Indonesia and the survival of Homo erectus in Asia.  

PubMed

Homo erectus was the first human lineage to disperse widely throughout the Old World, the only hominin in Asia through much of the Pleistocene, and was likely ancestral to H. sapiens. The demise of this taxon remains obscure because of uncertainties regarding the geological age of its youngest populations. In 1996, some of us co-published electron spin resonance (ESR) and uranium series (U-series) results indicating an age as young as 35-50 ka for the late H. erectus sites of Ngandong and Sambungmacan and the faunal site of Jigar (Indonesia). If correct, these ages favor an African origin for recent humans who would overlap with H. erectus in time and space. Here, we report (40)Ar/(39)Ar incremental heating analyses and new ESR/U-series age estimates from the "20 m terrace" at Ngandong and Jigar. Both data sets are internally consistent and provide no evidence for reworking, yet they are inconsistent with one another. The (40)Ar/(39)Ar analyses give an average age of 546±12 ka (sd±5 se) for both sites, the first reliable radiometric indications of a middle Pleistocene component for the terrace. Given the technical accuracy and consistency of the analyses, the argon ages represent either the actual age or the maximum age for the terrace and are significantly older than previous estimates. Most of the ESR/U-series results are older as well, but the oldest that meets all modeling criteria is 143 ka+20/-17. Most samples indicated leaching of uranium and likely represent either the actual or the minimum age of the terrace. Given known sources of error, the U-series results could be consistent with a middle Pleistocene age. However, the ESR and (40)Ar/(39)Ar ages preclude one another. Regardless, the age of the sites and hominins is at least bracketed between these estimates and is older than currently accepted. PMID:21738710

Indriati, Etty; Swisher, Carl C; Lepre, Christopher; Quinn, Rhonda L; Suriyanto, Rusyad A; Hascaryo, Agus T; Grün, Rainer; Feibel, Craig S; Pobiner, Briana L; Aubert, Maxime; Lees, Wendy; Antón, Susan C

2011-06-29

57

New fossils from Koobi Fora in northern Kenya confirm taxonomic diversity in early Homo.  

PubMed

Since its discovery in 1972 (ref. 1), the cranium KNM-ER 1470 has been at the centre of the debate over the number of species of early Homo present in the early Pleistocene epoch of eastern Africa. KNM-ER 1470 stands out among other specimens attributed to early Homo because of its larger size, and its flat and subnasally orthognathic face with anteriorly placed maxillary zygomatic roots. This singular morphology and the incomplete preservation of the fossil have led to different views as to whether KNM-ER 1470 can be accommodated within a single species of early Homo that is highly variable because of sexual, geographical and temporal factors, or whether it provides evidence of species diversity marked by differences in cranial size and facial or masticatory adaptation. Here we report on three newly discovered fossils, aged between 1.78 and 1.95 million years (Myr) old, that clarify the anatomy and taxonomic status of KNM-ER 1470. KNM-ER 62000, a well-preserved face of a late juvenile hominin, closely resembles KNM-ER 1470 but is notably smaller. It preserves previously unknown morphology, including moderately sized, mesiodistally long postcanine teeth. The nearly complete mandible KNM-ER 60000 and mandibular fragment KNM-ER 62003 have a dental arcade that is short anteroposteriorly and flat across the front, with small incisors; these features are consistent with the arcade morphology of KNM-ER 1470 and KNM-ER 62000. The new fossils confirm the presence of two contemporary species of early Homo, in addition to Homo erectus, in the early Pleistocene of eastern Africa. PMID:22874966

Leakey, Meave G; Spoor, Fred; Dean, M Christopher; Feibel, Craig S; Antón, Susan C; Kiarie, Christopher; Leakey, Louise N

2012-08-01

58

Evolution of the Genus Homo  

NASA Astrophysics Data System (ADS)

Definition of the genus Homo is almost as fraught as the definition of Homo sapiens. We look at the evidence for “early Homo,” finding little morphological basis for extending our genus to any of the 2.5-1.6-myr-old fossil forms assigned to “early Homo” or Homo habilis/rudolfensis. We also point to heterogeneity among “early African Homo erectus,” and the lack of apomorphies linking these fossils to the Asian Homo erectus group, a cohesive regional clade that shows some internal variation, including brain size increase over time. The first truly cosmopolitan Homo species is Homo heidelbergensis, known from Africa, Europe, and China following 600 kyr ago. One species sympatric with it included the >500-kyr-old Sima de los Huesos fossils from Spain, clearly distinct from Homo heidelbergensis and the oldest hominids assignable to the clade additionally containing Homo neanderthalensis. This clade also shows evidence of brain size expansion with time; but although Homo neanderthalensis had a large brain, it left no unequivocal evidence of the symbolic consciousness that makes our species unique. Homo sapiens clearly originated in Africa, where it existed as a physical entity before it began (also in that continent) to show the first stirrings of symbolism. Most likely, the biological underpinnings of symbolic consciousness were exaptively acquired in the radical developmental reorganization that gave rise to the highly characteristic osteological structure of Homo sapiens, but lay fallow for tens of thousands of years before being “discovered” by a cultural stimulus, plausibly the invention of language.

Tattersall, Ian; Schwartz, Jeffrey H.

2009-05-01

59

Behavioral and Environmental Background to ‘Out-of-Africa I’ and the Arrival of Homo erectus in East Asia  

Microsoft Academic Search

\\u000a Current evidence of hominin fossils and artifacts in China and Indonesia points to the arrival and persistence of the genus\\u000a Homo in East Asia by 1.7 million years ago (Ma). By at least 1.66 Ma, East Asian hominins had spread across a wide range of biotic\\u000a and climatic zones, spanning 7°S–40°N on the basis of well-constrained age data from the

Richard Potts; Robin Teague

60

Dated Co-Occurrence of Homo erectus and Gigantopithecus from Tham Khuyen Cave, Vietnam  

Microsoft Academic Search

Tham Khuyen Cave (Lang Son Province, northern Vietnam) is one of the more significant sites to yield fossil vertebrates in east Asia. During the mid-1960s, excavation in a suite of deposits produced important hominoid dental remains of middle Pleistocene age. We undertake more rigorous analyses of these sediments to understand the fluvial dynamics of Pleistocene cave infilling as they determine

Russell Ciochon; Vu The Long; Roy Larick; Luis Gonzalez; Rainer Grun; John de Vos; Charles Yonge; Lois Taylor; Hiroyuki Yoshida; Mark Reagan

1996-01-01

61

Energetics in Homo erectus and other early hominins: The consequences of increased lower-limb length  

Microsoft Academic Search

Previous studies of daily energy expenditure (DEE) in hominin fossils have estimated locomotor costs using a formula that was based on six species, all 18kg or less in mass, including no primates, and that has a number of other problems when applied in an ecological context. It is well established that the energetic cost of human walking is lower than

Karen L. Steudel-Numbers

2006-01-01

62

Man the Fat Hunter: The Demise of Homo erectus and the Emergence of a New Hominin Lineage in the Middle Pleistocene (ca. 400 kyr) Levant  

Microsoft Academic Search

The worldwide association of H. erectus with elephants is well documented and so is the preference of humans for fat as a source of energy. We show that rather than a matter of preference, H. erectus in the Levant was dependent on both elephants and fat for his survival. The disappearance of elephants from the Levant some 400 kyr ago

Miki Ben-Dor; Avi Gopher; Israel Hershkovitz; Ran Barkai

2011-01-01

63

Bone strength and athletic ability in hominids: Ardipithecus ramidus to Homo sapiens  

NASA Astrophysics Data System (ADS)

The ability of the femur to resist bending stresses is determined by its midlength cross-sectional geometry, its length and the elastic properties of the mineral part of the bone. The animal's athletic ability, determined by a ``bone strength index,'' is limited by this femoral bending strength in relation to the loads on the femur. This analysis is applied to the fossil record for Homo sapiens, Homo neanderthalensis, Homo erectus, Homo habilis, Australopithecus afarensis and Ardipithecus ramidus. Evidence that the femoral bone strength index of modern Homo sapiens has weakened over the last 50,000 years is found.

Lee, S. A.

2013-03-01

64

A single lineage in early Pleistocene Homo: size variation continuity in early Pleistocene Homo crania from East Africa and Georgia.  

PubMed

The relationship between Homo habilis and early African Homo erectus has been contentious because H. habilis was hypothesized to be an evolutionary stage between Australopithecus and H. erectus, more than a half-century ago. Recent work re-dating key African early Homo localities and the discovery of new fossils in East Africa and Georgia provide the opportunity for a productive re-evaluation of this topic. Here, we test the hypothesis that the cranial sample from East Africa and Georgia represents a single evolutionary lineage of Homo spanning the approximately 1.9-1.5 Mya time period, consisting of specimens attributed to H. habilis and H. erectus. To address issues of small sample sizes in each time period, and uneven representation of cranial data, we developed a novel nonparametric randomization technique based on the variance in an index of pairwise difference from a broad set of fossil comparisons. We fail to reject the hypothesis of a single lineage this period by identifying a strong, time-dependent pattern of variation throughout the sequence. These results suggest the need for a reappraisal of fossil evidence from other regions within this time period and highlight the critical nature of the Plio-Pleistocene boundary for understanding the early evolution of the genus Homo. PMID:23461332

Van Arsdale, Adam P; Wolpoff, Milford H

2012-12-20

65

Dating of Fossil Hominid: Problems and Perspectives.  

National Technical Information Service (NTIS)

The hominid dating anterior to the Homo Erectus has been based up to now on the rocks and minerals geochronology of vulcanic origin in stratigraphic relation with the fossils. Two methods are widely used, potassium-argon and uranium fission track dating. ...

G. Poupeau J. Danon A. K. Baksi

1984-01-01

66

Man the Fat Hunter: The Demise of Homo erectus and the Emergence of a New Hominin Lineage in the Middle Pleistocene (ca. 400 kyr) Levant  

PubMed Central

The worldwide association of H. erectus with elephants is well documented and so is the preference of humans for fat as a source of energy. We show that rather than a matter of preference, H. erectus in the Levant was dependent on both elephants and fat for his survival. The disappearance of elephants from the Levant some 400 kyr ago coincides with the appearance of a new and innovative local cultural complex – the Levantine Acheulo-Yabrudian and, as is evident from teeth recently found in the Acheulo-Yabrudian 400-200 kyr site of Qesem Cave, the replacement of H. erectus by a new hominin. We employ a bio-energetic model to present a hypothesis that the disappearance of the elephants, which created a need to hunt an increased number of smaller and faster animals while maintaining an adequate fat content in the diet, was the evolutionary drive behind the emergence of the lighter, more agile, and cognitively capable hominins. Qesem Cave thus provides a rare opportunity to study the mechanisms that underlie the emergence of our post-erectus ancestors, the fat hunters.

Ben-Dor, Miki; Gopher, Avi; Hershkovitz, Israel; Barkai, Ran

2011-01-01

67

Brain size and encephalization in early to Mid-Pleistocene Homo.  

PubMed

Important changes in the brain have occurred during the course of human evolution. Both absolute and relative size increases can be documented for species of Homo, culminating in the appearance of modern humans. One species that is particularly well-represented by fossil crania is Homo erectus. The mean capacity for 30 individuals is 973 cm(3). Within this group there is substantial variation, but brain size increases slightly in specimens from later time periods. Other Middle Pleistocene crania differ from those of Homo erectus. Characters of the facial skeleton, vault, and cranial base suggest that fossils from sites such as Arago Cave in France, the Sima de los Huesos in Spain, Bodo in Ethiopia, Broken Hill in Zambia, and perhaps Dali in China belong to the taxon Homo heidelbergensis. Ten of these mid-Quaternary hominins have brains averaging 1,206 cm(3) in volume, and many fall beyond the limits of size predicted for Homo erectus of equivalent age. When orbit height is used to construct an index of relative brain size, it is apparent that the (significant) increase in volume documented for the Middle Pleistocene individuals is not simply a consequence of larger body mass. Encephalization quotient values confirm this finding. These changes in absolute and relative brain size can be taken as further corroborative evidence for a speciation event, in which Homo erectus produced a daughter lineage. It is probable that Homo heidelbergensis originated in Africa or western Eurasia and then ranged widely across the Old World. Archaeological traces indicate that these populations differed in their technology and behavior from earlier hominins. PMID:15160365

Rightmire, G Philip

2004-06-01

68

Bone strength and athletic ability in hominids: Ardipithecus ramidus to Homo sapiens  

NASA Astrophysics Data System (ADS)

A methodology for the evaluation of the athletic ability of animals based on the strength of their femur and their body mass is developed. The ability of the femur to resist bending stresses is determined by its midlength cross-sectional geometry, its length and the elastic properties of the mineral part of the bone. The animal's athletic ability, determined by a ``bone strength index,'' is limited by this femoral bending strength in relation to the loads on the femur. This analysis is applied to the fossil record for Homo sapiens, Homo neanderthalensis, Homo erectus, Homo habilis, Australopithecus afarensis and Ardipithecus ramidus. Evidence that the femoral bone strength index of modern Homo sapiens has weakened over the last 50,000 years is found.

Lee, Scott

2012-10-01

69

Brief Communication: Shape analysis of the MT 1 proximal articular surface in fossil hominins and shod and unshod Homo.  

PubMed

As a follow-up study to Proctor et al. (Am J Phys Anthropol 135 (2008) 216-224), this study quantifies the first metatarsal proximal articular surface using three-dimensional morphometrics to test for differences in articular surface shape between habitually shod and habitually unshod humans. In addition, differences in shape between Homo, Pan, Gorilla, and Hylobates are compared to the fossil hominin specimens A. L. 333-54, Stw 562, Stw 573 ("Little Foot"), OH 8, SKX 5017, and SK 1813. No difference in surface shape was found between habitually shod and habitually unshod humans. There is a clear quantitative division in articular surface shape between humans and apes that is more pronounced than a previous study by Proctor et al. (Am J Phys Anthropol 135 (2008) 216-224), due to additional landmarks present in this study. The specimen OH 8 is indistinguishable from modern Homo. The fossils A. L. 333-54, Stw 562, and Stw 573 are intermediate in shape between humans and apes. The specimens SKX 5017 and SK 1813 have a more apelike articular surface. When combined with other characteristics, this trait suggests that Paranthropus used a degree of abduction during locomotion that was much less than that in extant apes, but greater than that in Australopithecus, allowing for some small degree of grasping ability. PMID:20925078

Proctor, Daniel J

2010-12-01

70

Pachyosteosclerosis suggests archaic Homo frequently collected sessile littoral foods.  

PubMed

Fossil skeletons of Homo erectus and related specimens typically had heavy cranial and postcranial bones, and it has been hypothesised that these represent adaptations, or are responses, to various physical activities such as endurance running, heavy exertion, and/or aggressive behavior. According to the comparative biological data, however, skeletons that show a combination of disproportionally large diameters, extremely compact bone cortex, and very narrow medullary canals are associated with aquatic or semi-aquatic tetrapods that wade, and/or dive for sessile foods such as hard-shelled invertebrates in shallow waters. These so-called pachyosteosclerotic bones are less supple and more brittle than non-pachyosteosclerotic bones, and marine biologists agree that they function as hydrostatic ballast for buoyancy control. This paper discusses the possibility that heavy skeletons in archaic Homo might be associated with part-time collection of sessile foods in shallow waters. PMID:21741646

Verhaegen, Marc; Munro, Stephen

2011-07-08

71

Early evidence of the genus Homo in East Asia.  

PubMed

The timing and route of the earliest dispersal from Africa to Eastern Asia are contentious topics in the study of early human evolution because Asian hominin fossil sites with precise age constraints are very limited. Here we report new high-resolution magnetostratigraphic results that place stringent age controls on excavated hominin incisors and stone tools from the Yuanmou Basin, southwest China. The hominin-bearing layer resides in a reverse polarity magnetozone just above the upper boundary of the Olduvai subchron, yielding an estimated age of 1.7Ma. The finding represents the age of the earliest documented presence of Homo, with affinities to Homo erectus, in mainland East Asia. This age estimate is roughly the same as for H. erectus in island Southeast Asia and immediately prior to the oldest archaeological evidence in northeast Asia. Mammalian fauna and pollen obtained directly from the hominin site indicate that the Yuanmou hominins lived in a varied habitat of open vegetation with patches of bushland and forest on an alluvial fan close to a lake or swamp. The age and location are consistent with a rapid southern migration route of initial hominin populations into Eastern Asia. PMID:18842287

Zhu, R X; Potts, R; Pan, Y X; Yao, H T; Lü, L Q; Zhao, X; Gao, X; Chen, L W; Gao, F; Deng, C L

2008-10-07

72

Variations and asymmetries in regional brain surface in the genus Homo.  

PubMed

Paleoneurology is an important field of research within human evolution studies. Variations in size and shape of an endocast help to differentiate among fossil hominin species whereas endocranial asymmetries are related to behavior and cognitive function. Here we analyse variations of the surface of the frontal, parieto-temporal and occipital lobes among different species of Homo, including 39 fossil hominins, ten fossil anatomically modern Homo sapiens and 100 endocasts of extant modern humans. We also test for the possible asymmetries of these features in a large sample of modern humans and observe individual particularities in the fossil specimens. This study contributes important new information about the brain evolution in the genus Homo. Our results show that the general pattern of surface asymmetry for the different regional brain surfaces in fossil species of Homo does not seem to be different from the pattern described in a large sample of anatomically modern H. sapiens, i.e., the right hemisphere has a larger surface than the left, as do the right frontal, the right parieto-temporal and the left occipital lobes compared with the contra-lateral side. It also appears that Asian Homo erectus specimens are discriminated from all other samples of Homo, including African and Georgian specimens that are also sometimes included in that taxon. The Asian fossils show a significantly smaller relative size of the parietal and temporal lobes. Neandertals and anatomically modern H. sapiens, who share the largest endocranial volume of all hominins, show differences when considering the relative contribution of the frontal, parieto-temporal and occipital lobes. These results illustrate an original variation in the pattern of brain organization in hominins independent of variations in total size. The globularization of the brain and the enlargement of the parietal lobes could be considered derived features observed uniquely in anatomically modern H. sapiens. PMID:22542169

Balzeau, Antoine; Holloway, Ralph L; Grimaud-Hervé, Dominique

2012-04-26

73

Evolution of M1 crown size and cusp proportions in the genus Homo.  

PubMed

Previous research into tooth crown dimensions and cusp proportions has proved to be a useful way to identify taxonomic differences in Pliocene and Pleistocene fossil hominins. The present study has identified changes in both M(1) crown size and cusp proportions within the genus Homo, with M(1) overall crown size reduction apparently occurring in two main stages. The first stage (a reduction of ca. 17%) is associated with the emergence of Homo ergaster and Homo erectus sensu stricto. The second stage (a reduction of ca. 10%) occurs in Homo sapiens, but the reduced modern human M(1) tooth crown size was only attained in Upper Paleolithic times. The absolute sizes of the individual cusps are highly positively correlated with overall crown size and dental reduction produces a reduction in the absolute size of each of the cusps. Most of the individual cusps scale isometrically with crown size, but the paracone shows a negative allometric relationship, indicating that the reduction in paracone size is less than in the other M(1) cusps. Thus, the phylogenetically oldest cusp in the upper molars also seems to be the most stable cusp (at least in the M(1)). The most striking change in M(1) cusp proportions is a change in the relative size of the areas of the paracone and metacone. The combination of a small relative paracone and a large relative metacone generally characterizes specimens attributed to early Homo, and the presence of this character state in Australopithecus and Paranthropus suggests it may represent the primitive condition for the later part of the hominin clade. In contrast, nearly all later Homo taxa, with the exception of Homo antecessor, show the opposite condition (i.e. a relatively large paracone and a relatively small metacone). This change in the relationship between the relative sizes of the paracone and metacone is related to an isometric reduction of the absolute size of the metacone. This metacone reduction occurs in the context of relative stability in the paracone as crown size decreases. Among later Homo taxa, both Homo heidelbergensis and Homo neanderthalensis show a further reduction of the metacone and an enlargement of the hypocone. Fossil and contemporary H. sapiens samples show a trend toward increasing the relative size of the protocone and decreasing the relative size of the hypocone. In Europe, modern human M(1) cusp proportions are essentially reached during the Upper Paleolithic. Although some variation was documented among the fossil taxa, we suggest that the relative size of the M(1) paracone and metacone areas may be useful for differentiating the earliest members of our genus from subsequent Homo species. PMID:19438761

Quam, Rolf; Bailey, Shara; Wood, Bernard

2009-05-01

74

Before the Emergence of Homo sapiens: Overview on the Early-to-Middle Pleistocene Fossil Record (with a Proposal about Homo heidelbergensis at the subspecific level).  

PubMed

The origin of H. sapiens has deep roots, which include two crucial nodes: (1) the emergence and diffusion of the last common ancestor of later Homo (in the Early Pleistocene) and (2) the tempo and mode of the appearance of distinct evolutionary lineages (in the Middle Pleistocene). The window between 1,000 and 500 thousand years before present appears of crucial importance, including the generation of a new and more encephalised kind of humanity, referred to by many authors as H. heidelbergensis. This species greatly diversified during the Middle Pleistocene up to the formation of new variants (i.e., incipient species) that, eventually, led to the allopatric speciation of H. neanderthalensis and H. sapiens. The special case furnished by the calvarium found near Ceprano (Italy), dated to 430-385?ka, offers the opportunity to investigate this matter from an original perspective. It is proposed to separate the hypodigm of a single, widespread, and polymorphic human taxon of the Middle Pleistocene into distinct subspecies (i.e., incipient species). The ancestral one should be H. heidelbergensis, including specimens such as Ceprano and the mandible from Mauer. PMID:21716742

Manzi, Giorgio

2011-05-04

75

Before the Emergence of Homo sapiens: Overview on the Early-to-Middle Pleistocene Fossil Record (with a Proposal about Homo heidelbergensis at the subspecific level)  

PubMed Central

The origin of H. sapiens has deep roots, which include two crucial nodes: (1) the emergence and diffusion of the last common ancestor of later Homo (in the Early Pleistocene) and (2) the tempo and mode of the appearance of distinct evolutionary lineages (in the Middle Pleistocene). The window between 1,000 and 500 thousand years before present appears of crucial importance, including the generation of a new and more encephalised kind of humanity, referred to by many authors as H. heidelbergensis. This species greatly diversified during the Middle Pleistocene up to the formation of new variants (i.e., incipient species) that, eventually, led to the allopatric speciation of H. neanderthalensis and H. sapiens. The special case furnished by the calvarium found near Ceprano (Italy), dated to 430–385?ka, offers the opportunity to investigate this matter from an original perspective. It is proposed to separate the hypodigm of a single, widespread, and polymorphic human taxon of the Middle Pleistocene into distinct subspecies (i.e., incipient species). The ancestral one should be H. heidelbergensis, including specimens such as Ceprano and the mandible from Mauer.

Manzi, Giorgio

2011-01-01

76

Age and biostratigraphic significance of the Punung Rainforest Fauna, East Java, Indonesia, and implications for Pongo and Homo.  

PubMed

The Punung Fauna is a key component in the biostratigraphic sequence of Java. It represents the most significant faunal turnover on the island in the last 1.5 million years, when Stegodon and other archaic mammal species characteristic of earlier Faunal stages were replaced by a fully modern fauna that included rainforest-dependent species such as Pongo pygmaeus (orangutan). Here, we report the first numerical ages for the Punung Fauna obtained by luminescence and uranium-series dating of the fossil-bearing deposits and associated flowstones. The Punung Fauna contained in the dated breccia is of early Last Interglacial age (between 128+/-15 and 118+/-3 ka). This result has implications for the age of the preceding Ngandong Fauna, including Homo erectus remains found in the Ngandong Terrace, and for the timing of Homo sapiens arrival in Southeast Asia, in view of claims for a modern human tooth associated with the Punung breccia. PMID:17706269

Westaway, K E; Morwood, M J; Roberts, R G; Rokus, A D; Zhao, J-x; Storm, P; Aziz, F; van den Bergh, G; Hadi, P; Jatmiko; de Vos, J

2007-08-13

77

The Origin of Homo  

Microsoft Academic Search

Despite a steady increase in the number and diversity of African Middle Pliocene hominin fossils, paleoanthropolo-gists are\\u000a not now substantially closer to understanding the temporal, geographical or ecological contexts of the origin of the Homo clade than was the case in 1964, when Louis Leakey, Phillip Tobias and John Napier introduced Homo habilis as the earliest species of the human

William H. Kimbel

78

Dental Evidence for Diets of Early Homo  

Microsoft Academic Search

The evolution of diet in the earliest members of our genus, Homo rudolfensis, H. habilis and H. erectus has received increased attention over the past few years (see Ungar et al., 2006a for review). Many models have been constructed,\\u000a based largely on nutritional studies combined with direct analogy (with living peoples or non-human primates) or on contextual\\u000a evidence, such as

Peter S. Ungar; Robert S. Scott

79

Homo floresiensis: a cladistic analysis.  

PubMed

The announcement of a new species, Homo floresiensis, a primitive hominin that survived until relatively recent times is an enormous challenge to paradigms of human evolution. Until this announcement, the dominant paradigm stipulated that: 1) only more derived hominins had emerged from Africa, and 2) H. sapiens was the only hominin since the demise of Homo erectus and Homo neanderthalensis. Resistance to H. floresiensis has been intense, and debate centers on two sets of competing hypotheses: 1) that it is a primitive hominin, and 2) that it is a modern human, either a pygmoid form or a pathological individual. Despite a range of analytical techniques having been applied to the question, no resolution has been reached. Here, we use cladistic analysis, a tool that has not, until now, been applied to the problem, to establish the phylogenetic position of the species. Our results produce two equally parsimonious phylogenetic trees. The first suggests that H. floresiensis is an early hominin that emerged after Homo rudolfensis (1.86Ma) but before H. habilis (1.66Ma, or after 1.9Ma if the earlier chronology for H. habilis is retained). The second tree indicates H. floresiensis branched after Homo habilis. PMID:19628252

Argue, D; Morwood, M J; Sutikna, T; Jatmiko; Saptomo, E W

2009-07-23

80

Relative limb strength and locomotion in Homo habilis.  

PubMed

The Homo habilis OH 62 partial skeleton has played an important, although controversial role in interpretations of early Homo locomotor behavior. Past interpretive problems stemmed from uncertain bone length estimates and comparisons using external bone breadth proportions, which do not clearly distinguish between modern humans and apes. Here, true cross-sectional bone strength measurements of the OH 62 femur and humerus are compared with those of modern humans and chimpanzees, as well as two early H. erectus specimens-KNM-WT 15000 and KNM-ER 1808. The comparative sections include two locations in the femur and two in the humerus in order to encompass the range of possible section positions in the OH 62 specimens. For each combination of section locations, femoral to humeral strength proportions of OH 62 fall below the 95% confidence interval of modern humans, and for most comparisons, within the 95% confidence interval of chimpanzees. In contrast, the two H. erectus specimens both fall within or even above the modern human distributions. This indicates that load distribution between the limbs, and by implication, locomotor behavior, was significantly different in H. habilis from that of H. erectus and modern humans. When considered with other postcranial evidence, the most likely interpretation is that H. habilis, although bipedal when terrestrial, still engaged in frequent arboreal behavior, while H. erectus was a completely committed terrestrial biped. This adds to the evidence that H. habilis (sensu stricto) and H. erectus represent ecologically distinct, parallel lineages during the early Pleistocene. PMID:18711733

Ruff, Christopher

2009-01-01

81

Fossils  

NSDL National Science Digital Library

4th Grade Science Standard 4: Students will understand how fossils are formed, where they may be found in Utah, and how they can be used to make inferences. DISCOVERING FOSSILS!!

101

A comparative study of frontal bone morphology among Pleistocene hominin fossil groups.  

PubMed

Features of the frontal bone that are conventionally used to distinguish among fossil hominin groups were quantitatively examined. Fifty-five fossil crania dating from the early to the late Pleistocene were analyzed. Using a modified pantograph, outlines of the frontal bone were collected along the midsagittal and two parasagittal planes. The profile from nasion to bregma, as well as two profiles above the medial and lateral sections of the orbit, respectively, extending from the orbital margin to the coronal suture were traced. The outlines were measured using Elliptical Fourier Function Analysis (EFFA), which enabled a quantification of aspects of the frontal bone that have historically been described primarily in nonmetric or linear terms. Four measurements were obtained: 1) overall morphology as expressed in the Fourier harmonic amplitudes; 2) maximum projection of the supraorbital torus at three points along the browridge (glabella and the medial and lateral aspects of the torus above the orbit); 3) maximum distance of the frontal squama from the frontal chord, capturing forehead curvature; and 4) nasion-bregma chord length. The results indicate that the midsagittal profile is significantly different among all Pleistocene groups in analyses that include both size and shape, as well as size-adjusted data. Homo erectus is significantly different from the late Pleistocene groups (Neandertals and early modern H. sapiens) in glabellar projection. Anatomically modern humans are significantly different from all other groups in both raw and size-standardized analyses of all three outlines that captured overall morphology, as well as forehead curvature and lateral supraorbital torus prominence, and middle Pleistocene Homo are significantly different in both medial and lateral overall parasagittal form. However, for the majority of analyses there were no significant differences among the Pleistocene archaic groups in supraorbital torus projection, frontal squama curvature, nasion-bregma chord length, or overall frontal bone morphology. PMID:19878968

Athreya, Sheela

2009-10-29

102

Liang Bua Homo floresiensis mandibles and mandibular teeth: a contribution to the comparative morphology of a new hominin species.  

PubMed

In 2004, a new hominin species, Homo floresiensis, was described from Late Pleistocene cave deposits at Liang Bua, Flores. H. floresiensis was remarkable for its small body-size, endocranial volume in the chimpanzee range, limb proportions and skeletal robusticity similar to Pliocene Australopithecus, and a skeletal morphology with a distinctive combination of symplesiomorphic, derived, and unique traits. Critics of H. floresiensis as a novel species have argued that the Pleistocene skeletons from Liang Bua either fall within the range of living Australomelanesians, exhibit the attributes of growth disorders found in modern humans, or a combination of both. Here we describe the morphology of the LB1, LB2, and LB6 mandibles and mandibular teeth from Liang Bua. Morphological and metrical comparisons of the mandibles demonstrate that they share a distinctive suite of traits that place them outside both the H. sapiens and H. erectus ranges of variation. While having the derived molar size of later Homo, the symphyseal, corpus, ramus, and premolar morphologies share similarities with both Australopithecus and early Homo. When the mandibles are considered with the existing evidence for cranial and postcranial anatomy, limb proportions, and the functional anatomy of the wrist and shoulder, they are in many respects closer to African early Homo or Australopithecus than to later Homo. Taken together, this evidence suggests that the ancestors of H. floresiensis left Africa before the evolution of H. erectus, as defined by the Dmanisi and East African evidence. PMID:19589559

Brown, Peter; Maeda, Tomoko

2009-07-08

103

Craniofacial morphology of Homo floresiensis: description, taxonomic affinities, and evolutionary implication.  

PubMed

This paper describes in detail the external morphology of LB1/1, the nearly complete and only known cranium of Homo floresiensis. Comparisons were made with a large sample of early groups of the genus Homo to assess primitive, derived, and unique craniofacial traits of LB1 and discuss its evolution. Principal cranial shape differences between H. floresiensis and Homo sapiens are also explored metrically. The LB1 specimen exhibits a marked reductive trend in its facial skeleton, which is comparable to the H. sapiens condition and is probably associated with reduced masticatory stresses. However, LB1 is craniometrically different from H. sapiens showing an extremely small overall cranial size, and the combination of a primitive low and anteriorly narrow vault shape, a relatively prognathic face, a rounded oval foramen that is greatly separated anteriorly from the carotid canal/jugular foramen, and a unique, tall orbital shape. Whereas the neurocranium of LB1 is as small as that of some Homo habilis specimens, it exhibits laterally expanded parietals, a weak suprameatal crest, a moderately flexed occipital, a marked facial reduction, and many other derived features that characterize post-habilis Homo. Other craniofacial characteristics of LB1 include, for example, a relatively narrow frontal squama with flattened right and left sides, a marked frontal keel, posteriorly divergent temporal lines, a posteriorly flexed anteromedial corner of the mandibular fossa, a bulbous lateral end of the supraorbital torus, and a forward protruding maxillary body with a distinct infraorbital sulcus. LB1 is most similar to early Javanese Homo erectus from Sangiran and Trinil in these and other aspects. We conclude that the craniofacial morphology of LB1 is consistent with the hypothesis that H. floresiensis evolved from early Javanese H. erectus with dramatic island dwarfism. However, further field discoveries of early hominin skeletal remains from Flores and detailed analyses of the finds are needed to understand the evolutionary history of this endemic hominin species. PMID:22036083

Kaifu, Yousuke; Baba, Hisao; Sutikna, Thomas; Morwood, Michael J; Kubo, Daisuke; Saptomo, E Wahyu; Jatmiko; Awe, Rokhus Due; Djubiantono, Tony

2011-10-28

104

Megadontia, striae periodicity and patterns of enamel secretion in Plio-Pleistocene fossil hominins  

PubMed Central

Early hominins formed large and thick-enamelled cheek-teeth within relatively short growth periods as compared with modern humans. To understand better the developmental basis of this process, we measured daily enamel increments, or cross striations, in 17 molars of Plio-Pleistocene hominins representing seven different species, including specimens attributed to early Homo. Our results show considerable variation across species, although all specimens conformed to the known pattern characterised by greater values in outer than inner enamel, and greater cuspal than cervical values. We then compared our results with the megadontia index, which represents tooth size in relation to body mass, for each species to assess the effect of daily growth rates on tooth size. Our results indicate that larger toothed (megadont) taxa display higher rates or faster forming enamel than smaller toothed hominins. By forming enamel quickly, large tooth crowns were able to develop within the constraints of shorter growth periods. Besides daily increments, many animals express long-period markings (striae of Retzius) in their enamel. We report periodicity values (number of cross striations between adjacent striae) in 14 new specimens of Australopithecus afarensis, Paranthropus aethiopicus, Paranthropus boisei, Homo habilis, Homo rudolfensis and Homo erectus, and show that long-period striae express a strong association with male and average male–female body mass. Our results for Plio-Pleistocene hominins show that the biological rhythms that give rise to long-period striae are encompassed within the range of variation known for modern humans, but show a lower mean and modal value of 7 days in australopithecines. In our sample of early Homo, mean and modal periodicity values were 8 days, and therefore similar to modern humans. These new data on daily rates of enamel formation and periodicity provide a better framework to interpret surface manifestations of internal growth markings on fossil hominin tooth crowns. Importantly, our data on early hominin cross striation variation may now contribute towards solving difficult taxonomic diagnoses where much may depend on fragmentary molar remains and enamel structure.

Lacruz, Rodrigo S; Dean, M Christopher; Ramirez-Rozzi, Fernando; Bromage, Timothy G

2008-01-01

105

Brain size of Homo floresiensis and its evolutionary implications.  

PubMed

The extremely small endocranial volume (ECV) of LB1, the type specimen of Homo floresiensis, poses a challenge in our understanding of human brain evolution. Some researchers hypothesize dramatic dwarfing of relative brain size from Homo erectus presumably without significant decrease in intellectual function, whereas others expect a lesser degree of brain diminution from a more primitive, small-brained form of hominin currently undocumented in eastern Asia. However, inconsistency in the published ECVs for LB1 (380-430 cc), unclear human intraspecific brain-body size scaling and other uncertainties have hampered elaborative modelling of its brain size reduction. In this study, we accurately determine the ECV of LB1 using high-resolution micro-CT scan. The ECV of LB1 thus measured, 426 cc, is larger than the commonly cited figure in previous studies (400 cc). Coupled with brain-body size correlation in Homo sapiens calculated based on a sample from 20 worldwide modern human populations, we construct new models of the brain size reduction in the evolution of H. floresiensis. The results show a more significant contribution of scaling effect than previously claimed. PMID:23595271

Kubo, Daisuke; Kono, Reiko T; Kaifu, Yousuke

2013-04-17

106

Homo economicus belief inhibits trust.  

PubMed

As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners' benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals' homo economicus belief and inhibit their trust. It seems that people's increasing homo economicus belief may serve as one cause of the worldwide decline of trust. PMID:24146907

Xin, Ziqiang; Liu, Guofang

2013-10-16

107

Homo Economicus Belief Inhibits Trust  

PubMed Central

As a foundational concept in economics, the homo economicus assumption regards humans as rational and self-interested actors. In contrast, trust requires individuals to believe partners’ benevolence and unselfishness. Thus, the homo economicus belief may inhibit trust. The present three experiments demonstrated that the direct exposure to homo economicus belief can weaken trust. And economic situations like profit calculation can also activate individuals’ homo economicus belief and inhibit their trust. It seems that people’s increasing homo economicus belief may serve as one cause of the worldwide decline of trust.

Xin, Ziqiang; Liu, Guofang

2013-01-01

108

Large Mammalian Carnivores as a Taphonomic Factor in the Bone Accumulation at Zhoukoudian  

Microsoft Academic Search

The entire fossil assemblage of Homo erectus excavated from Zhoukoudian Locality 1 has been studied from casts and available originals to assess taphonomic damage and determine the agent(s) of damage. Body part representation, the micromorphology of breakage, and the close similarity of Zhoukoudian Homo erectus damage to that documented in modern African hyaenid-modified bone assemblages lead us to conclude that

Noel T. BOAZ; Russell L. CIOCHON; XU Qinqi; LIU Jinyi

2000-01-01

109

Stratigraphic, chronological and behavioural contexts of Pleistocene Homo sapiens from Middle Awash, Ethiopia.  

PubMed

Clarifying the geographic, environmental and behavioural contexts in which the emergence of anatomically modern Homo sapiens occurred has proved difficult, particularly because Africa lacked adequate geochronological, palaeontological and archaeological evidence. The discovery of anatomically modern Homo sapiens fossils at Herto, Ethiopia, changes this. Here we report on stratigraphically associated Late Middle Pleistocene artefacts and fossils from fluvial and lake margin sandstones of the Upper Herto Member of the Bouri Formation, Middle Awash, Afar Rift, Ethiopia. The fossils and artefacts are dated between 160,000 and 154,000 years ago by precise age determinations using the 40Ar/39Ar method. The archaeological assemblages contain elements of both Acheulean and Middle Stone Age technocomplexes. Associated faunal remains indicate repeated, systematic butchery of hippopotamus carcasses. Contemporary adult and juvenile Homo sapiens fossil crania manifest bone modifications indicative of deliberate mortuary practices. PMID:12802333

Clark, J Desmond; Beyene, Yonas; WoldeGabriel, Giday; Hart, William K; Renne, Paul R; Gilbert, Henry; Defleur, Alban; Suwa, Gen; Katoh, Shigehiro; Ludwig, Kenneth R; Boisserie, Jean-Renaud; Asfaw, Berhane; White, Tim D

2003-06-12

110

A revision of the Dubois crocodylians, Gavialis bengawanicus and Crocodylus ossifragus, from the Pleistocene Homo erectus beds of Java  

Microsoft Academic Search

Revision of the two extinct Javanese crocodylian species Gavialis bengawanicusDubois, 1908, and Crocodylus ossifragusDubois, 1908, indicates that only the former is valid and that the latter is a junior subjective synonym of the extant C. siamensisSchneider, 1801. Gavialis bengawanicus is diagnosed by a relatively small number of maxillary and dentary teeth, a modest maxillary process developed into the lacrimal, a

Massimo Delfino; John De Vos

2010-01-01

111

Endurance running and the evolution of Homo.  

PubMed

Striding bipedalism is a key derived behaviour of hominids that possibly originated soon after the divergence of the chimpanzee and human lineages. Although bipedal gaits include walking and running, running is generally considered to have played no major role in human evolution because humans, like apes, are poor sprinters compared to most quadrupeds. Here we assess how well humans perform at sustained long-distance running, and review the physiological and anatomical bases of endurance running capabilities in humans and other mammals. Judged by several criteria, humans perform remarkably well at endurance running, thanks to a diverse array of features, many of which leave traces in the skeleton. The fossil evidence of these features suggests that endurance running is a derived capability of the genus Homo, originating about 2 million years ago, and may have been instrumental in the evolution of the human body form. PMID:15549097

Bramble, Dennis M; Lieberman, Daniel E

2004-11-18

112

Marquee Fossils  

ERIC Educational Resources Information Center

|Professors of an online graduate-level paleontology class developed the concept of marquee fossils--fossils that have one or more unique characteristics that capture the attention and direct observation of students. In the classroom, Marquee fossils integrate the geology, biology, and environmental science involved in the study of fossilized

Clary, Renee; Wandersee, James

2008-01-01

113

Marquee Fossils  

ERIC Educational Resources Information Center

Professors of an online graduate-level paleontology class developed the concept of marquee fossils--fossils that have one or more unique characteristics that capture the attention and direct observation of students. In the classroom, Marquee fossils integrate the geology, biology, and environmental science involved in the study of fossilized

Clary, Renee; Wandersee, James

2008-01-01

114

A bivariate approach to the widening of the frontal lobes in the genus Homo.  

PubMed

Within the genus Homo, the most encephalized taxa (Neandertals and modern humans) show relatively wider frontal lobes than either Homo erectus or australopithecines. The present analysis considers whether these changes are associated with a single size-based or allometric pattern (positive allometry of the width of the anterior endocranial fossa) or with a more specific and non-allometric pattern. The relationship between hemispheric length, maximum endocranial width, and frontal width at Broca's area was investigated in extant and extinct humans. Our results do not support positive allometry for the frontal lobe's width in relation to the main endocranial diameters within modern humans (Homo sapiens). Also, the correlation between frontal width and hemispheric length is lower than the correlation between frontal width and parieto-temporal width. When compared with the australopithecines, the genus Homo could have experienced a non-allometric widening of the brain at the temporo-parietal areas, which is most evident in Neandertals. Modern humans and Neandertals also display a non-allometric widening of the anterior endocranial fossa at the Broca's cap when compared with early hominids, again more prominent in the latter group. Taking into account the contrast between the intra-specific patterns and the between-species differences, the relative widening of the anterior fossa can be interpreted as a definite evolutionary character instead of a passive consequence of brain size increase. This expansion is most likely associated with correspondent increments of the underlying neural mass, or at least with a geometrical reallocation of the frontal cortical volumes. Although different structural changes of the cranial architecture can be related to such variations, the widening of the frontal areas is nonetheless particularly interesting when some neural functions (like language or working memory, decision processing, etc.) and related fronto-parietal cortico-cortical connections are taken into account. PMID:20035967

Bruner, Emiliano; Holloway, Ralph L

2009-12-24

115

Australopithecus sediba at 1.977 Ma and implications for the origins of the genus Homo.  

PubMed

Newly exposed cave sediments at the Malapa site include a flowstone layer capping the sedimentary unit containing the Australopithecus sediba fossils. Uranium-lead dating of the flowstone, combined with paleomagnetic and stratigraphic analysis of the flowstone and underlying sediments, provides a tightly constrained date of 1.977 ± 0.002 million years ago (Ma) for these fossils. This refined dating suggests that Au. sediba from Malapa predates the earliest uncontested evidence for Homo in Africa. PMID:21903808

Pickering, Robyn; Dirks, Paul H G M; Jinnah, Zubair; de Ruiter, Darryl J; Churchil, Steven E; Herries, Andy I R; Woodhead, Jon D; Hellstrom, John C; Berger, Lee R

2011-09-08

116

A complete skull from Dmanisi, Georgia, and the evolutionary biology of early Homo.  

PubMed

The site of Dmanisi, Georgia, has yielded an impressive sample of hominid cranial and postcranial remains, documenting the presence of Homo outside Africa around 1.8 million years ago. Here we report on a new cranium from Dmanisi (D4500) that, together with its mandible (D2600), represents the world's first completely preserved adult hominid skull from the early Pleistocene. D4500/D2600 combines a small braincase (546 cubic centimeters) with a large prognathic face and exhibits close morphological affinities with the earliest known Homo fossils from Africa. The Dmanisi sample, which now comprises five crania, provides direct evidence for wide morphological variation within and among early Homo paleodemes. This implies the existence of a single evolving lineage of early Homo, with phylogeographic continuity across continents. PMID:24136960

Lordkipanidze, David; Ponce de León, Marcia S; Margvelashvili, Ann; Rak, Yoel; Rightmire, G Philip; Vekua, Abesalom; Zollikofer, Christoph P E

2013-10-18

117

Discovering Fossils: Fossil Tools & Resources  

NSDL National Science Digital Library

Fossil enthusiasts Roy Shephard and Luci Algar combined their professional skills in media and education to develop this informative and entertaining website. Designed to be educational and accessible to children, this site presents a wide variety of information about fossils. The site contains a nice collection of images and diagrams; and includes a fossils guide for beginners, information on preparing fossils, a collection of fossil myths, information on ammonites, and more. The site also contains a Games & Activities section for teachers and students, a glossary of fossil terms, a neat diagram depicting the evolution of life on our planet, and even some free fossil desktop images.

118

Mandibular molar root morphology in Neanderthals and Late Pleistocene and recent Homo sapiens  

Microsoft Academic Search

Neanderthals have a distinctive suite of dental features, including large anterior crown and root dimensions and molars with enlarged pulp cavities. Yet, there is little known about variation in molar root morphology in Neanderthals and other recent and fossil members of Homo. Here, we provide the first comprehensive metric analysis of permanent mandibular molar root morphology in Middle and Late

Kornelius Kupczik; Jean-Jacques Hublin

2010-01-01

119

The Primitive Wrist of Homo floresiensis and Its Implications for Hominin Evolution  

Microsoft Academic Search

Whether the Late Pleistocene hominin fossils from Flores, Indonesia, represent a new species, Homo floresiensis, or pathological modern humans has been debated. Analysis of three wrist bones from the holotype specimen (LB1) shows that it retains wrist morphology that is primitive for the African ape-human clade. In contrast, Neandertals and modern humans share derived wrist morphology that forms during embryogenesis,

Matthew W. Tocheri; Caley M. Orr; Susan G. Larson; Thomas Sutikna; Jatmiko; E. Wahyu Saptomo; Rokus Awe Due; Tony Djubiantono; Michael J. Morwood; William L. Jungers

2007-01-01

120

"Fossil" Forecasting.  

ERIC Educational Resources Information Center

|Presents a density study in which students calculate the density of limestone substrate to determine if the specimen contains any fossils. Explains how to make fossils and addresses national standards. (YDS)|

Brody, Michael J.; deOnis, Ann

2001-01-01

121

The Homo sapiens Cave hominin site of Mulan Mountain, Jiangzhou District, Chongzuo, Guangxi with emphasis on its age  

Microsoft Academic Search

One of the most hotly debated and frontal issues in paleoanthropology focuses on the origins of modern humans. Recently, an\\u000a incomplete hominin mandible with a distinctly weaker mental protuberance than modern human and a great variety of coexisting\\u000a fossil mammals were unearthed from the Homo sapiens Cave of Mulan Mountain, Chongzuo, Guangxi. The mammalian fauna from the Homo sapiens Cave

ChangZhu Jin; WenShi Pan; YingQi Zhang; YanJun Cai; QinQi Xu; ZhiLu Tang; Wei Wang; Yuan Wang; JinYi Liu; DaGong Qin; R. Lawrence Edwards; Hai Cheng

2009-01-01

122

4th Grade Fossils  

NSDL National Science Digital Library

Introduction to Fossils What is a fossil What Is a Fossil? Body and Trace Fossils Body and Trace Fossils Life of a Vertebrate fossil Life of a Vertebrate Fossil Finding Fossils Finding Fossils How fossils are found How fossils are formed Fossils found in Utah Fossils found in Utah Where fossils are found in Utah Where fossils are found in Utah Utah County Map Utah County Map ...

Richrigby

2010-01-26

123

Fossil fuels  

Microsoft Academic Search

The recovery, handling and combustion of fossil fuels is damaging the environment. This damage may ultimately cause many plant and animal species to become extinct. If we continue to increase our use of fossil fuels for energy production, humanity may ultimately become one of the species that perish. This is an overwhelming reason to stop the use of fossil fuels

Herman Daly

1994-01-01

124

Fossils 1: Fossils and Dinosaurs  

NSDL National Science Digital Library

This lesson will go beyond naming dinosaurs and give students a broad understanding of how we know about the great beasts. This lesson focuses on what we have learned and can learn from fossils. The follow-up lesson, Dinosaurs Fossils - Uncovering the Facts, explores what information can be discerned by comparing fossils to living organisms.

Science Netlinks;

2001-10-20

125

Fossil Find  

NSDL National Science Digital Library

In this classroom activity, middle school students simulate a "dinosaur dig." The activity opens with background information for teachers about fossils. Working in groups, students excavate fossil sites created in advance by the teacher, or other group of students, and try to reconstruct a chicken skeleton. The activity closes with a two-page student worksheet that directs students to diagram the fossil site and includes probing questions to help them decode their findings.

126

Finding Fossils  

NSDL National Science Digital Library

This activity (located on page 4 of the PDF) is a full inquiry investigation to determine the age of fossils based on where they are discovered. Groups of learners will dig for fossils embedded in a cake of multiple layers, carefully excavating each stratum and eventually preparing a chart from their notes for discussion with the group. The two main lessons from this exercise are that fossils from different layers come from different eras and that multiple interpretations of incomplete fossil evidence are possible. Relates to linked video, DragonflyTV GPS: Baby Dinosaurs.

Twin Cities Public Television, Inc.

2007-01-01

127

Fossil Fuels.  

ERIC Educational Resources Information Center

This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

Crank, Ron

128

Fossil Crinoids  

Microsoft Academic Search

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history,

Hans Hess; William I. Ausich; Carlton E. Brett; Michael J. Simms

2003-01-01

129

Fossil Crinoids  

Microsoft Academic Search

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history,

Hans Hess; William I. Ausich; Carlton E. Brett; Michael J. Simms

1999-01-01

130

Fossil Fuels.  

ERIC Educational Resources Information Center

|This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

Crank, Ron

131

Ediacara Fossils  

ERIC Educational Resources Information Center

|Now, a research team from Virginia Tech and Nanjing Institute of Geology and Paleontology has discovered uniquely well-preserved fossil forms from 550-million-year-old rocks of the Ediacaran Period. The research appears in the Proceedings of the National Academy of Sciences. The discovery of these unusually preserved fossils reveals unprecedented…

Science Teacher, 2005

2005-01-01

132

Fossil Crinoids  

NASA Astrophysics Data System (ADS)

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history, occurrence, preservation and ecology. The main part of the book is devoted to assemblages of intact fossil crinoids, which are described in their geological setting in twenty-three chapters ranging from the Ordovician to the Tertiary. The final chapter deals with living sea lilies and feather stars. The volume is exquisitely illustrated with abundant photographs and line drawings of crinoids from sites around the world. This authoritative account recreates a fascinating picture of fossil crinoids for paleontologists, geologists, evolutionary and marine biologists, ecologists and amateur fossil collectors.

Hess, Hans; Ausich, William I.; Brett, Carlton E.; Simms, Michael J.

2003-01-01

133

Fossil Crinoids  

NASA Astrophysics Data System (ADS)

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history, occurrence, preservation and ecology. The main part of the book is devoted to assemblages of intact fossil crinoids, which are described in their geological setting in twenty-three chapters ranging from the Ordovician to the Tertiary. The final chapter deals with living sea lilies and feather stars. The volume is exquisitely illustrated with abundant photographs and line drawings of crinoids from sites around the world. This authoritative account recreates a fascinating picture of fossil crinoids for paleontologists, geologists, evolutionary and marine biologists, ecologists and amateur fossil collectors.

Hess, Hans; Ausich, William I.; Brett, Carlton E.; Simms, Michael J.

1999-10-01

134

Fossil Fuels  

NSDL National Science Digital Library

How much does the United States depend on fossil fuels? This web page, part of a site on the future of energy, introduces students to fossil fuels as an energy source. Here students read about the uses, benefits, and limitations of fossil fuels. There is also information on how these fuels are distributed geographically and how they affect the U.S. economy through supply and demand. Thought-provoking questions afford students opportunities to reflect on what they've read. Articles about clean coal, the national energy policy, and the formation of fossil fuels, together with a fossil fuels fact sheet, are accessible from a sidebar. In addition, five PBS NewsHour links to energy-related stories are included.

Project, Iowa P.

2004-01-01

135

Fossils 1: Fossils and Dinosaurs  

NSDL National Science Digital Library

In this lesson, students will understand what can be learned from fossils and in doing so, realize the difference between fact and theory. This lesson is the first of a two-part series on fossils. These lessons will go beyond naming dinosaurs and give students a broad understanding of how we know about the great beasts. They will start to acquire knowledge of the fossil record in preparation for learning about evolution and natural selection, concepts they will study in high school. This particular lesson focuses on what we have learned and can learn from fossils. In the first part, students will discuss what we know about horses. They will then do the same for a Stegosaurus. Another part of the lesson briefly covers how fossils are formed.

136

Upper Pleistocene Homo sapiens from the Tabon cave (Palawan, The Philippines): description and dating of new discoveries  

Microsoft Academic Search

Among the poor fossil record of Southeast Asian Upper Pleistocene Homo sapiens, the Tabon human remains [12] are frequently cited in the literature despite very scarce published palaeoanthropological data. A recent Filipino-French joint work confirmed the significance of the discoveries made in the 1960s: a frontal bone and two mandibular fragments that have been recently described and dated [9]. Simultaneously,

Florent Détroit; Eusebio Dizon; Christophe Falguères; Sébastien Hameau; Wilfredo Ronquillo; François Sémah

2004-01-01

137

Fossil Halls  

NSDL National Science Digital Library

The American Museum of Natural History is home to the world's largest collection of vertebrate fossils, totaling nearly one million specimens. This Web site offers visitors a virtual visit to the Museum's famed Fossil Halls. It features sections on Cladistics, Vertebrate Evolution, Exhibit Specimens, a collection of 19 biographies of important people in paleontology and Virtual Tours of four of the halls. There is also an elementary school teacher guide to the museum exhibit.

138

Are Homo sapiens nonsupranuchal fossa and Neanderthal suprainiac fossa convergent traits?  

PubMed

The autapomorphic status of the Neanderthal suprainiac fossa was recently confirmed. This was a result of a detailed analysis of the internal bone composition in the area of the suprainiac depression on Neanderthal and Homo sapiens specimens. However, while anatomical differences between Neanderthal suprainiac fossa and the depression in the inion region of the occipital bone of fossil and recent Homo sapiens have been discussed in detail, the etiology of these structures has not been resolved. In this article, the hypothesis that the Homo sapiens non-supranuchal fossa and the Neanderthal suprainiac fossa both formed to maintain the optimal shape of the occipital plane (to minimize strain on the posterior cranial vault) is tested. First, the variation in the expression of the fossa above inion in the crania of recent Homo sapiens from European, African, and Australian samples was examined, and the degree of structural similarity between these depressions and the Neanderthal suprainiac fossa was assessed. Next, the relationship between the shape of the occipital squama in the midsagittal plane and two particular features (the degree of the occipital torus development and the occurrence of a depression in the inion region that is not the supranuchal fossa) were analyzed. Based on the results, it is suggested that the Homo sapiens non-supranuchal fossa and Neanderthal suprainiac fossa are convergent traits. PMID:21404232

Nowaczewska, Wioletta

2010-12-23

139

Dermatitis and systemic mycosis in lined seahorses Hippocampus erectus associated with a marine-adapted Fusarium solani species complex pathogen  

Technology Transfer Automated Retrieval System (TEKTRAN)

During a 4 month epizootic, 100% of 152 lined seahorses Hippocampus erectus in three separate groups died while in quarantine following shipment to a public aquarium. Twelve animals with skin depigmentation and ulceration were received by the Aquatic Pathology Service, University of Georgia, College...

140

Effect of Spacing on the Biomass Production and Allocation in Conocarpus erectus L. Trees Grown in Riyadh, Saudi Arabia  

Microsoft Academic Search

The main objectives of this study were to investigate the effect of different spacing levels on the biomass production and allocation in Conocarpus erectus trees grown in the arid environments of Saudi Arabia and to develop allometric equations for predicting the total above-ground biomass of these trees as well the biomass of each tree component (main stem, branches and foliage).

Said S. Hegazy; Ibrahim M. Aref; Hamad Al-Mefarrej; Lotfy I. El-Juhany

141

Earliest evidence of modern human life history in North African early Homo sapiens  

PubMed Central

Recent developmental studies demonstrate that early fossil hominins possessed shorter growth periods than living humans, implying disparate life histories. Analyses of incremental features in teeth provide an accurate means of assessing the age at death of developing dentitions, facilitating direct comparisons with fossil and modern humans. It is currently unknown when and where the prolonged modern human developmental condition originated. Here, an application of x-ray synchrotron microtomography reveals that an early Homo sapiens juvenile from Morocco dated at 160,000 years before present displays an equivalent degree of tooth development to modern European children at the same age. Crown formation times in the juvenile's macrodont dentition are higher than modern human mean values, whereas root development is accelerated relative to modern humans but is less than living apes and some fossil hominins. The juvenile from Jebel Irhoud is currently the oldest-known member of Homo with a developmental pattern (degree of eruption, developmental stage, and crown formation time) that is more similar to modern H. sapiens than to earlier members of Homo. This study also underscores the continuing importance of North Africa for understanding the origins of human anatomical and behavioral modernity. Corresponding biological and cultural changes may have appeared relatively late in the course of human evolution.

Smith, Tanya M.; Tafforeau, Paul; Reid, Donald J.; Grun, Rainer; Eggins, Stephen; Boutakiout, Mohamed; Hublin, Jean-Jacques

2007-01-01

142

Genetic and Fossil Evidence for the Origin of Modern Humans  

Microsoft Academic Search

The origin of living Homo sapiens has once again been the subject of much debate. Genetic data on present human population relationships and data from the Pleistocene fossil hominid record are used to compare two contrasting models for the origin of modern humans. Both genetics and paleontology support a recent African origin for modern humans rather than a long period

C. B. Stringer; P. Andrews

1988-01-01

143

The Homo Energeticus: maturity, inheritance, identity  

NASA Astrophysics Data System (ADS)

In this letter, modern society’s intimate bond to the convenience and reliability of delivered energy services results in a form of identification I call the Homo Energeticus. The Homo Energeticus relies upon a mature system of services for achieving an equivalency of status and prestige that is historically similar to the morality of a noble class. I describe the uniqueness of this identity by its imperative for acquiring experience through an invisibility of energy expenditures. In this way, the Homo Energeticus cultivates a highly individualized life whose ambience of perfection, while created personally, is only successful insofar as it conceals energy expenditures in labor and supply.

Mason, Arthur

2013-03-01

144

Bird Fossils  

NSDL National Science Digital Library

A fossil of a small, feathered animal, Longisquama insignis, that lived approximately 220 million years ago (Ma) in what is now Central Asia, was re-discovered recently in the dusty drawers of a Moscow museum collection. This discovery has rocked the paleontological world because the fossil exhibits feather impressions, making it possibly the world's oldest known bird. Archaeopteryx, thought until now to be the oldest true bird, is from a limestone deposit in Germany dated at approximately 145 Ma. This new fossil discovery fires the debate over whether birds are descended from dinosaurs, or branched off from an earlier group of reptiles. This week's In The News takes a look at scientists' latest understanding of the reptile-bird evolutionary transition, and the surrounding controversies.

145

Crown size and cusp proportions in Homo antecessor upper first molars. A comment on Quam et al. 2009.  

PubMed

A recent evaluation of upper first molar (M¹) crown size and cusp proportions in the genus Homo (Quam et al. 2009) describes Homo antecessor as maintaining a primitive pattern of cusp proportions, similar to that identified in australopithecines and the earliest members of the genus Homo. These results contrast with those of Gómez-Robles et al. (2007), who described the crown shape in these molars as derived and similar to Neanderthals and European Homo heidelbergensis. The reassessment of these measurements following the same methodology described by Quam et al. (2009) in all the M(1) s that are currently part of the hypodigm of H. antecessor demonstrates that the fossils from TD6 not only have the same cusp proportions identified in later Homo species, but also a strongly reduced metacone and a large hypocone shared with Middle and Upper Pleistocene members of the Neanderthal lineage. The evolutionary significance of these features should be evaluated in light of the results provided by recently discovered dental, cranial, mandibular, and postcranial H. antecessor fossils. PMID:21208207

Gómez-Robles, Aida; de Castro, José María Bermúdez; Martinón-Torres, María; Prado-Simón, Leyre

2010-11-26

146

Crown size and cusp proportions in Homo antecessor upper first molars. A comment on Quam et al. 2009  

PubMed Central

A recent evaluation of upper first molar (M1) crown size and cusp proportions in the genus Homo (Quam et al. 2009) describes Homo antecessor as maintaining a primitive pattern of cusp proportions, similar to that identified in australopithecines and the earliest members of the genus Homo. These results contrast with those of Gómez-Robles et al. (2007), who described the crown shape in these molars as derived and similar to Neanderthals and European Homo heidelbergensis. The reassessment of these measurements following the same methodology described by Quam et al. (2009) in all the M1s that are currently part of the hypodigm of H. antecessor demonstrates that the fossils from TD6 not only have the same cusp proportions identified in later Homo species, but also a strongly reduced metacone and a large hypocone shared with Middle and Upper Pleistocene members of the Neanderthal lineage. The evolutionary significance of these features should be evaluated in light of the results provided by recently discovered dental, cranial, mandibular, and postcranial H. antecessor fossils.

Gomez-Robles, Aida; de Castro, Jose Maria Bermudez; Martinon-Torres, Maria; Prado-Simon, Leyre

2011-01-01

147

Fossil Fuels  

NSDL National Science Digital Library

The Department of Energy Web site Fossil Fuels is billed as an energy education site mainly for older kids, but can be enjoyed by adult kids as well. The site gives an introduction to energy, and then a more detailed look at the acquisition and uses of coal, oil, and gas. The good descriptions, illustrations, and animations, along with the frequent questions page and glossary of related terms, combine to give a clear and enlightening overview of the subject.

148

Radiometric dating of the type-site for Homo heidelbergensis at Mauer, Germany.  

PubMed

The Mauer mandible, holotype of Homo heidelbergensis, was found in 1907 in fluvial sands deposited by the Neckar River 10 km southeast of Heidelberg, Germany. The fossil is an important key to understanding early human occupation of Europe north of the Alps. Given the associated mammal fauna and the geological context, the find layer has been placed in the early Middle Pleistocene, but confirmatory chronometric evidence has hitherto been missing. Here we show that two independent techniques, the combined electron spin resonance/U-series method used with mammal teeth and infrared radiofluorescence applied to sand grains, date the type-site of Homo heidelbergensis at Mauer to 609 ± 40 ka. This result demonstrates that the mandible is the oldest hominin fossil reported to date from central and northern Europe and raises questions concerning the phyletic relationship of Homo heidelbergensis to more ancient populations documented from southern Europe and in Africa. We address the paleoanthropological significance of the Mauer jaw in light of this dating evidence. PMID:21041630

Wagner, Günther A; Krbetschek, Matthias; Degering, Detlev; Bahain, Jean-Jacques; Shao, Qingfeng; Falguères, Christophe; Voinchet, Pierre; Dolo, Jean-Michel; Garcia, Tristan; Rightmire, G Philip

2010-11-01

149

Citrate utilization by homo- and heterofermentative lactobacilli  

Microsoft Academic Search

Citrate utilization by several homo- and heterofermentative lactobacilli was determined in Kempler and McKay and in calcium citrate media. The last medium with glucose permitted best to distinguish citrate-fermenting lactobacilli. Lactobacillus rhamnosus ATCC 11443, Lactobacillus zeae ATCC 15820 and Lactobacillus plantarum ATCC 8014 used citrate as sole energy source, whereas in the other strains, glucose and citrate were cometabolized. Some

R. Medina de Figueroa; F. Alvarez; A. Pesce de Ruiz Holgado; G. Oliver; F. Sesma

2000-01-01

150

Yawn Contagion and Empathy in Homo sapiens  

Microsoft Academic Search

The ability to share others' emotions, or empathy, is crucial for complex social interactions. Clinical, psychological, and neurobiological clues suggest a link between yawn contagion and empathy in humans (Homo sapiens). However, no behavioral evidence has been provided so far. We tested the effect of different variables (e.g., country of origin, sex, yawn characteristics) on yawn contagion by running mixed

Ivan Norscia; Elisabetta Palagi

2011-01-01

151

Dental metric assessment of the omo fossils: implications for the phylogenetic position of Australopithecus africanus.  

PubMed

The discovery of Australopithecus afarensis has led to new interpretations of hominid phylogeny, some of which reject A. africanus as an ancestor of Homo. Analysis of buccolingual tooth crown dimensions in australopithecines and Homo species by Johanson and White (Science 202:321-330, 1979) revealed that the South African gracile australopithecines are intermediate in size between Laetoli/hadar hominids and South African robust hominids. Homo, on the other hand, displays dimensions similar to those of A. afarensis and smaller than those of other australopithecines. These authors conclude, therefore, that A. africanus is derived in the direction of A. robustus and is not an ancestor of the Homo clade. However, there is a considerable time gap (ca. 800,000 years) between the Laetoli/Hadar specimens and the earliest Homo specimens; "gracile" hominids from Omo fit into this chronological gap and are from the same geographic area. Because the early specimens at Omo have been designated A. afarensis and the later specimens classified as Homo habilis, Omo offers a unique opportunity to test hypotheses concerning hominid evolution, especially regarding the phylogenetic status of A. africanus. Comparisons of mean cheek teeth breadths disclosed the significant (P less than or equal to 0.05) differences between the Omo sample and the Laetoli/Hadar fossils (P4, M2, and M3), the Homo fossils (P3, P4, M1, M2, and M1), and A. africanus (M3). Of the several possible interpretations of these data, it appears that the high degree of similarity between the Omo sample and the South African gracile australopithecine material warrants considering the two as geographical variants of A. africanus. The geographic, chronologic, and metric attributes of the Omo sample argue for its lineal affinity with A. afarensis and Homo. In conclusion, a consideration of hominid postcanine dental metrics provides no basis for removing A. africanus from the ancestry of the Homo lineage. PMID:3099582

Hunt, K; Vitzthum, V J

1986-10-01

152

Fossil Hominids: The Evidence for Human Evolution  

NSDL National Science Digital Library

This Web site from Talk.Origins, a "Usenet newsgroup devoted to the discussion and debate of biological and physical origins," aims to "provide an overview of the study of human evolution, and of the currently accepted fossil evidence." Recognized for excellence by a number of science and education organizations, this site has been updated to include new material concerning Homo habilus and two newly discovered fossil hominid skulls. As before, the site also offers an overview of the latest developments in paleoanthropology, general information about hominid species, and links and references, as well as closely following the controversial evolution vs. creationism debate. The site is simply presented and easy to navigate, and offers a convenient way to keep current with paleoanthropological issues.

1996-01-01

153

[Adaptive evolution of the Homo mitochondrial genome].  

PubMed

Adaptive evolution of 12 protein-coding mitochondrial genes in members of genus Homo (Denisova hominin (H. sp. Altai), Neandertals (H. neanderthalensis) and modern humans (H. sapiens)) has been evaluated by assessing the pattern of changes in the physicochemical properties of amino acid replacements during the primate evolution. It has been found that in the Homo molecular adaptation (positive destabilizing selection) become apparent in the form of 12 radical amino acid replacements accompanied by statistically significant (P < 0.001) changes of physicochemical properties that probably had the functional consequences. These replacements have occurred on the stage of a common ancestor of the Homo (in CO2 and CytB genes) as well as with the appearance of the common ancestor of Neandertals and modern humans (in CO1 and ND5 genes). Radical amino acid replacements were mainly revealed in the cytochrome c oxidase complex IV and cytochrome bc1 complex III, thus coinciding with general trend of increasing of non-synonymous changes in mtDNA genes coding subunits of complexes III and IV proteins in anthropoid primates. PMID:22393781

Maliarchuk, B A

154

Human evolution.  

PubMed

The common ancestor of modern humans and the great apes is estimated to have lived between 5 and 8 Myrs ago, but the earliest evidence in the human, or hominid, fossil record is Ardipithecus ramidus, from a 4.5 Myr Ethiopian site. This genus was succeeded by Australopithecus, within which four species are presently recognised. All combine a relatively primitive postcranial skeleton, a dentition with expanded chewing teeth and a small brain. The most primitive species in our own genus, Homo habilis and Homo rudolfensis, are little advanced over the australopithecines and with hindsight their inclusion in Homo may not be appropriate. The first species to share a substantial number of features with later Homo is Homo ergaster, or 'early African Homo erectus', which appears in the fossil record around 2.0 Myr. Outside Africa, fossil hominids appear as Homo erectus-like hominids, in mainland Asia and in Indonesia close to 2 Myr ago; the earliest good evidence of 'archaic Homo' in Europe is dated at between 600-700 Kyr before the present. Anatomically modern human, or Homo sapiens, fossils are seen first in the fossil record in Africa around 150 Kyr ago. Taken together with molecular evidence on the extent of DNA variation, this suggests that the transition from 'archaic' to 'modern' Homo may have taken place in Africa. PMID:8976151

Wood, B

1996-12-01

155

The morphometric relationship of Upper Cave 101 and 103 to modern Homo sapiens.  

PubMed

Since the discovery of the Homo sapiens crania from the Upper Cave of Zhoukoudian in northern China (UC 101, UC 102, and UC 103), no clear consensus has arisen regarding their affinities with modern populations. We use linear craniofacial measurements to compare UC 101 and UC 103 to a worldwide sample of H. sapiens that includes Paleoamericans and Archaic Indians, and employ Mahalanobis distance analysis and associated unweighted, unrestricted canonical variate analysis for the comparisons. Analyses indicate that UC 101 has consistent affinities with Easter Island and European populations, whereas UC 103 has more tenuous similarities with Australo-Melanesian groups. Both fossils exhibit some similarities to certain Paleoamerican and Archaic Indian individuals, but rarely cluster together. Upper Cave 103 is more of an outlier to modern populations than is UC 101. The fossils are not representative of any group to which they have been compared, but may be part of the generalized population that was ancestral to Paleoamericans. PMID:12890442

Cunningham, Deborah L; Jantz, Richard L

2003-07-01

156

Mandible and Taxonomy of the Earliest European Homo  

Microsoft Academic Search

Although variability of the mandible makes it problematic for taxonomy, the holotypes of three of the oldest European species,\\u000a Home georgicus, H. antecessor, H. heidelbergensis, are mandibles. Moreover, the distinctive validity of these three species cannot be established from these particular mandibles.\\u000a The holotype of H. georgicus is pathological and similar to H. erectus in some important features, while others

P. F. Fabbri

2006-01-01

157

A description of the geological context, discrete traits, and linear morphometrics of the Middle Pleistocene hominin from Dali, Shaanxi Province, China.  

PubMed

In 1978, a nearly complete hominin fossil cranium was recovered from loess deposits at the site of Dali in Shaanxi Province, northwestern China. It was subsequently briefly described in both English and Chinese publications. Here we present a comprehensive univariate and nonmetric description of the specimen and provide comparisons with key Middle Pleistocene Homo erectus and non-erectus hominins from Eurasia and Africa. In both respects we find affinities with Chinese H. erectus as well as African and European Middle Pleistocene hominins typically referred to as Homo heidelbergensis. Specifically, the Dali specimen possesses a low cranial height, relatively short and arched parietal bones, an angled occipital bone, and a nonprominent articular tubercle relative to the preglenoid surface all of which distinguish it from Afro/European Middle Pleistocene Homo and align it with Asian H. erectus. At the same time, it displays a more derived morphology of the supraorbital torus and supratoral sulcus and a thinner tympanic plate than H. erectus, a relatively long upper (lambda-inion) occipital plane with a clear separation of inion and opisthocranion, and an absolute and relative increase in brain size, all of which align it with African and European Middle Pleistocene Homo. Finally, traits such as the form of the frontal keel and the relatively short, broad midface align Dali specifically with other Chinese specimens from the Middle Pleistocene and Late Pleistocene, including H. erectus, and differentiate these from the Afro/European specimens of this time period. PMID:23283667

Wu, Xinzhi; Athreya, Sheela

2013-01-01

158

The dynamics of reproductive rate, offspring survivorship and growth in the lined seahorse, Hippocampus erectus Perry, 1810  

PubMed Central

Summary Seahorses are the vertebrate group with the embryonic development occurring within a special pouch in males. To understand the reproductive efficiency of the lined seahorse, Hippocampus erectus Perry, 1810 under controlled breeding experiments, we investigated the dynamics of reproductive rate, offspring survivorship and growth over births by the same male seahorses. The mean brood size of the 1-year old pairs in the 1st birth was 85.4±56.9 per brood, which was significantly smaller than that in the 6th birth (465.9±136.4 per brood) (P<0.001). The offspring survivorship and growth rate increased with the births. The fecundity was positively correlated with the length of brood pouches of males and trunk of females. The fecundity of 1-year old male and 2-year old female pairs was significantly higher than that from 1-year old couples (P<0.001). The brood size (552.7±150.4) of the males who mated with females that were isolated for the gamete-preparation, was larger than those (467.8±141.2) from the long-term pairs (P<0.05). Moreover, the offspring from the isolated females had higher survival and growth rates. Our results showed that the potential reproductive rate of seahorses H. erectus increased with the brood pouch development.

Lin, Qiang; Li, Gang; Qin, Geng; Lin, Junda; Huang, Liangmin; Sun, Hushan; Feng, Peiyong

2012-01-01

159

Hominid Fossils from Dmanisi and Their Place Among the Early Hominids  

Microsoft Academic Search

Discoveries of Homo remains consisting of four craniums and four mandibles with several post- cranial remains, stone artifacts of Olduvai type Mode 1 (13) and faunal fossils that points to a latest Pliocene - earliest Pleistocene age during the excavations in Dmanisi, Republic of Georgia, yielding the age of 1.81 M. yr. (Ar40\\/Ar39) have reopened the debate about the first

David Lordkipanidze; Abesalom Vekua; Philip G. Rightmire; Ann Margvelashvili

160

Dental microwear texture analysis and diet in the Dmanisi hominins.  

PubMed

Reconstructions of foraging behavior and diet are central to our understanding of fossil hominin ecology and evolution. Current hypotheses for the evolution of the genus Homo invoke a change in foraging behavior to include higher quality foods. Recent microwear texture analyses of fossil hominin teeth have suggested that the evolution of Homo erectus may have been marked by a transition to a more variable diet. In this study, we used microwear texture analysis to examine the occlusal surface of 2 molars from Dmanisi, a 1.8 million year old fossil hominin site in the Republic of Georgia. The Dmanisi molars were characterized by a moderate degree of surface complexity (Asfc), low textural fill volume (Tfv), and a relatively low scale of maximum complexity (Smc), similar to specimens of early African H. erectus. While caution must be used in drawing conclusions from this small sample (n = 2), these results are consistent with continuity in diet as H. erectus expanded into Eurasia. PMID:22030152

Pontzer, Herman; Scott, Jessica R; Lordkipanidze, David; Ungar, Peter S

2011-10-24

161

Theropod Fossil Hunt Dispatch  

NSDL National Science Digital Library

This site outlines the step by step progression as a rare fossil is found, authenticated and identified. Follow along as a paleontologist pursues a well-preserved fossil of Sinosauropteryx, a feathered dromaeosaur. The site is enhanced with several photographs.

162

Descriptions of the lower limb skeleton of Homo floresiensis.  

PubMed

Bones of the lower extremity have been recovered for up to nine different individuals of Homo floresiensis - LB1, LB4, LB6, LB8, LB9, LB10, LB11, LB13, and LB14. LB1 is represented by a bony pelvis (damaged but now repaired), femora, tibiae, fibulae, patellae, and numerous foot bones. LB4/2 is an immature right tibia lacking epiphyses. LB6 includes a fragmentary metatarsal and two pedal phalanges. LB8 is a nearly complete right tibia (shorter than that of LB1). LB9 is a fragment of a hominin femoral diaphysis. LB10 is a proximal hallucal phalanx. LB11 includes pelvic fragments and a fragmentary metatarsal. LB13 is a patellar fragment, and LB14 is a fragment of an acetabulum. All skeletal remains recovered from Liang Bua were extremely fragile, and some were badly damaged when they were removed temporarily from Jakarta. At present, virtually all fossil materials have been returned, stabilized, and hardened. These skeletal remains are described and illustrated photographically. The lower limb skeleton exhibits a uniquely mosaic pattern, with many primitive-like morphologies; we have been unable to find this combination of ancient and derived (more human-like) features in either healthy or pathological modern humans, regardless of body size. Bilateral asymmetries are slight in the postcranium, and muscle markings are clearly delineated on all bones. The long bones are robust, and the thickness of their cortices is well within the ranges seen in healthy modern humans. LB1 is most probably a female based on the shape of her greater sciatic notch, and the marked degree of lateral iliac flaring recalls that seen in australopithecines such as "Lucy" (AL 288-1). The metatarsus has a human-like robusticity formula, but the proximal pedal phalanges are relatively long and robust (and slightly curved). The hallux is fully adducted, but we suspect that a medial longitudinal arch was absent. PMID:19062072

Jungers, W L; Larson, S G; Harcourt-Smith, W; Morwood, M J; Sutikna, T; Due Awe, Rokhus; Djubiantono, T

2008-12-04

163

Giant trees from the Middle Pleistocene of Northern Thailand  

NASA Astrophysics Data System (ADS)

Giant fossil trees from the Middle Pleistocene of Thailand are described. The longest log is measured at 72.2 m. Morphological analysis suggests that the original trees towered to more than 100 m, in a wet tropical forest. As contemporaneous archaic pebble tools were reported in the same area, the subtropical rainforest was no impenetrable ecological barrier to a population of Homo erectus.

Philippe, Marc; Boonchai, Nareerat; Ferguson, David K.; Jia, Hui; Songtham, Wickanet

2013-04-01

164

Kinetic analysis of estrogen receptor homo- and heterodimerization in vitro  

Microsoft Academic Search

The coexistence of ER? and ER? suggests that active receptor complexes are present as homo- or heterodimers. In addition each of three forms of active receptors may trigger different cellular responses. A real-time biosensor based on surface plasmon resonance was used as instrument to determine binding kinetics of homo- and heterodimerization of estrogen receptor ? and ?. Partially purified full-length

Elisabeth Jisa; Alois Jungbauer

2003-01-01

165

Is It a Fossil?  

NSDL National Science Digital Library

This formative assessment item is used to uncover students' ideas about fossils before a lesson has begun. Students will determine whether examples are fossils, and what sort of inferences can be made about prior environments because of fossils. This probe is aligned with the National Science Education Standards. Resources are provided along with instructional suggestions.

Fries-Gaither, Jessica

166

Fossils of Kentucky  

NSDL National Science Digital Library

Information on Kentucky fossils is organized by type, age, and region. General fossil facts are given, and there are out-of-print technical reports available at this site. A fossil identification key helps users identify unknown fossils by shape or by descriptive terms. A Geologic and Paleontologic Cookbook offers directions for creating edible models that illustrate prehistoric and other Earth Science concepts (such as trilobite cookies and layer-cake geology). There are links to more K-12 activities and other fossil websites.

167

Types of Fossils  

NSDL National Science Digital Library

The word fossil, derived from a Latin word meaning 'something dug up', refers to the preserved remains or traces of ancient life. Careful study of these remains can answer questions about life and evolution, and provide information about the history of Earth itself; for example, revealing that a tropical sea was present where only a desert exists today. This interactive feature explores the kinds of things we can learn from several types of fossils that scientists study. Viewers can see examples of body fossils (shells, bones, etc.), trace fossils (tracks, burrows, etc.), and an example of a fossil which has attributes of both.

168

Fossil-energy program  

NASA Astrophysics Data System (ADS)

The increased utilization of coal and other fossil fuel alternatives as sources of clean energy is reported. The projects reported include: coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction, process analysis and engineering evaluations, fossil energy environmental analysis, environmental control technology, coal preparation waste utilization, atmospheric fluidized bed coal combustor for cogeneration, TVA FBC demonstration plant program technical support, PFBC systems analysis, FBC char utilization improvement, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology, generalized equilibrium models for liquid and gaseous fuel supplies, instrumentations and controls and fossil energy information center.

McNeese, L. E.

1982-01-01

169

Reconstructing the ups and downs of primate brain evolution: implications for adaptive hypotheses and Homo floresiensis  

PubMed Central

Background Brain size is a key adaptive trait. It is often assumed that increasing brain size was a general evolutionary trend in primates, yet recent fossil discoveries have documented brain size decreases in some lineages, raising the question of how general a trend there was for brains to increase in mass over evolutionary time. We present the first systematic phylogenetic analysis designed to answer this question. Results We performed ancestral state reconstructions of three traits (absolute brain mass, absolute body mass, relative brain mass) using 37 extant and 23 extinct primate species and three approaches to ancestral state reconstruction: parsimony, maximum likelihood and Bayesian Markov-chain Monte Carlo. Both absolute and relative brain mass generally increased over evolutionary time, but body mass did not. Nevertheless both absolute and relative brain mass decreased along several branches. Applying these results to the contentious case of Homo floresiensis, we find a number of scenarios under which the proposed evolution of Homo floresiensis' small brain appears to be consistent with patterns observed along other lineages, dependent on body mass and phylogenetic position. Conclusions Our results confirm that brain expansion began early in primate evolution and show that increases occurred in all major clades. Only in terms of an increase in absolute mass does the human lineage appear particularly striking, with both the rate of proportional change in mass and relative brain size having episodes of greater expansion elsewhere on the primate phylogeny. However, decreases in brain mass also occurred along branches in all major clades, and we conclude that, while selection has acted to enlarge primate brains, in some lineages this trend has been reversed. Further analyses of the phylogenetic position of Homo floresiensis and better body mass estimates are required to confirm the plausibility of the evolution of its small brain mass. We find that for our dataset the Bayesian analysis for ancestral state reconstruction is least affected by inclusion of fossil data suggesting that this approach might be preferable for future studies on other taxa with a poor fossil record.

2010-01-01

170

Découverte d’un nouvel hominidé à Dmanissi (Transcaucasie, Géorgie)  

Microsoft Academic Search

Four human remains: one mandible, two skulls and one metatarsus were discovered between 1991 and 1999 at the open-air site of Dmanisi, Georgia, in a precise stratigraphic, palaeontological and archaeological context, in volcanic ashes dated to 1.81 ± 0.05 Ma. The first studies of these fossils enable the authors to compare them with the morphology of archaic African Homo erectus, ascribed to Homo

Léo Gabounia; Marie-Antoinette de Lumley; Abesalom Vekua; David Lordkipanidze; Henry de Lumley

2002-01-01

171

Palaeopathological and variant conditions of the Homo heidelbergensis type specimen (Mauer, Germany).  

PubMed

Although early Homo specimens are now known from a number of African, Asian and European Middle Pleistocene sites, the taxon Homo heidelbergensis was initially introduced for the Mauer jaw recovered in 1907. Fossil hominids from the earlier Middle Pleistocene of Europe are very rare and the Mauer mandible is generally accepted as one of the most ancient, with an age of approximately 700 kyr. A new preparation of the mandible was conducted in 1996 and gave rise to the detailed palaeopathological examination which is presented here. Based on comparative analyses, the extreme breadth of the mandibular ramus and its flat intercondylar incision, in conjunction with the flattening and broadening of the coronoid process tip, results either from an idiosyncratic pattern of the course and insertion of the temporalis muscle on the coronoid process or from the temporalis possessing an accessory head. The incidence of periodontal pocketing, together with a vertical reduction of the alveolar margin to approximately 3.00 mm, and a slight protuberance formed in vicinity of the right M(2)can safely be interpreted as pathognomonic indications of periodontal disease. The short distance between the enamel-dentine junction of the teeth and the horizontal alveolar margins could either be an inherited variant or may result from incipient osteoporosis. In addition, an arthrotic condition with slight osteophytic peripheral exostoses and an arthrolit (i.e. an articular calculus or "joint mouse") on the left condylus articularisand a depression in the medial part of the left mandibular condyle extending into the inferior part of the ramus are present. These features are indicative of a trauma-induced osteochondrosis dissecans. The diagnosis therefore suggests that the observed depression results from a well-healed fracture. This traumatic event illustrates the demanding living conditions endured by humans during the European Middle Pleistocene. The variations and pathological conditions observed in Mauer do not question the mandible's role as type specimen for the taxon Homo heidelbergensis. PMID:12727464

Czarnetzki, A; Jakob, T; Pusch, C M

2003-04-01

172

Early stone technology on Flores and its implications for Homo floresiensis.  

PubMed

In the Soa Basin of central Flores, eastern Indonesia, stratified archaeological sites, including Mata Menge, Boa Lesa and Kobatuwa (Fig. 1), contain stone artefacts associated with the fossilized remains of Stegodon florensis, Komodo dragon, rat and various other taxa. These sites have been dated to 840-700 kyr bp (thousand years before present). The authenticity of the Soa Basin artefacts and their provenance have been demonstrated by previous work, but to quell lingering doubts, here we describe the context, attributes and production modes of 507 artefacts excavated at Mata Menge. We also note specific similarities, and apparent technological continuity, between the Mata Menge stone artefacts and those excavated from Late Pleistocene levels at Liang Bua cave, 50 km to the west. The latter artefacts, dated to between 95-74 and 12 kyr ago, are associated with the remains of a dwarfed descendent of S. florensis, Komodo dragon, rat and a small-bodied hominin species, Homo floresiensis, which had a brain size of about 400 cubic centimetres. The Mata Menge evidence negates claims that stone artefacts associated with H. floresiensis are so complex that they must have been made by modern humans (Homo sapiens). PMID:16738657

Brumm, Adam; Aziz, Fachroel; van den Bergh, Gert D; Morwood, Michael J; Moore, Mark W; Kurniawan, Iwan; Hobbs, Douglas R; Fullagar, Richard

2006-06-01

173

Effects of light intensity, stocking density, feeding frequency and salinity on the growth of sub-adult seahorses Hippocampus erectus Perry, 1810  

Microsoft Academic Search

This investigation examined the effects of light intensity, stocking density, feeding frequency and salinity on the growth of sub-adult seahorses, Hippocampus erectus and the development of the brood pouch in male seahorses. During the 8-week study, seahorses cultured at a light intensity of 1000 lx had higher incremental wet weight and standard length than those at 100 lx and 2500 lx. Seahorse growth

Qiang Lin; Dong Zhang; Junda Lin

2009-01-01

174

Brief communication: two human fossil deciduous molars from the Sangiran dome (Java, Indonesia): outer and inner morphology.  

PubMed

Currently, the human deciduous dental record from the Pleistocene deposits of the Sangiran Dome, Java, consists of only eight specimens. Here we report two deciduous crowns collected near the village of Pucung. While their precise geo-chronological context remains unknown, a provenance from the Early-Middle Pleistocene Kabuh Formation, or from the Early Pleistocene "Grenzbank Zone," is very likely. These isolated specimens consist of an upper first molar (PCG.1) and a lower second molar (PCG.2). Taxonomic discrimination of the Indonesian tooth record is difficult because of the convergence in crown size and appearance between Pongo and Homo. Accordingly, as PCG.2 still bears a concretion masking most of its features, we coupled the outer analysis of the two specimens with an investigation of their inner morphology. In addition to external characteristics, virtual imaging and quantitative assessment of inner morphology and tissue proportions support an attribution to the taxon Homo, and we preliminary allocate both specimens toH. erectus. PMID:22281866

Zanolli, Clément; Bondioli, Luca; Mancini, Lucia; Mazurier, Arnaud; Widianto, Harry; Macchiarelli, Roberto

2012-01-27

175

Fossil Shapes Extension Activity  

NSDL National Science Digital Library

In this activity students view photographs of 12 fossils and try to draw pictures of what the organisms looked like while they were alive. They then slice up fruit in various ways to get an idea of the difficulty of identifying an organism when only some of the hard parts may be exposed along a bedding surface, making it difficult to determine the true shape of the fossil, let alone the organism the fossil represents.

Greb, Stephen

176

Fossil Energy Program  

NASA Astrophysics Data System (ADS)

Increased utilization of coal and other fossil fuel alternatives as sources of clean energy is reported. The following topics are discussed: coal conversion development, chemical research and development, materials technology, component development and process evaluation studies, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, flue gas desulfurization, solid waste disposal, coal preparation waste utilization, plant control development, atmospheric fluidized bed coal combustor for cogeneration, TVA FBC demonstration plant program technical support, PFBC systems analysis, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology assessment, and general equilibrium models of liquid and gaseous fuel supplies.

McNeese, L. E.

1981-01-01

177

Plant Fossil Record  

NSDL National Science Digital Library

The International Organization of Palaeobotany (IOP) manages the Plant Fossil Record (PFR) database. The recently released version of the database, PFR2.2, offers descriptive details of most plant fossil genera and modern genera with fossil species. Based on "the scientific literature ... or museum collections," the database is organized into five sections: Genera (references for plant fossil genera published mostly before 1985), Descriptions (containing descriptive details of "the type specimens of more than 10,000 extinct plant genera"), Taxonomy (an "informal system of vascular plant classification" based on published schemes), Occurrences (distribution information and references), and Palaeo Maps.

178

The Primate Fossil Record  

NASA Astrophysics Data System (ADS)

The Primate Fossil Record is a profusely illustrated, up-to-date, and comprehensive treatment of primate paleontology that captures the complete history of the discovery and interpretation of primate fossils. Each chapter emphasizes three key components of the record of primate evolution: history of discovery, taxonomy of the fossils, and evolution of the adaptive radiations they represent. The volume objectively summarizes the many intellectual debates surrounding the fossil record and provides a foundation of reference information on the last two decades of astounding discoveries and worldwide field research for physical anthropologists, paleontologists, and evolutionary biologists.

Hartwig, Walter Carl

2002-05-01

179

Fossil Energy Website  

NSDL National Science Digital Library

This site serves as a gathering point for US Department of Energy (USDOE) materials related to fossil energy. Well-organized and easily navigated, the Fossil Energy Website hosts a wealth of resources, including fossil energy news, related USDOE budget information, an events calendar, in-depth explorations of selected issues, speeches and testimony, technical reports, statistics, and an overview of fossil energy-related global activities, among others. Additional resources include regulatory information, a news headlines ticker, a free email update service, related links, and professional notices.

180

Yawn contagion and empathy in Homo sapiens.  

PubMed

The ability to share others' emotions, or empathy, is crucial for complex social interactions. Clinical, psychological, and neurobiological clues suggest a link between yawn contagion and empathy in humans (Homo sapiens). However, no behavioral evidence has been provided so far. We tested the effect of different variables (e.g., country of origin, sex, yawn characteristics) on yawn contagion by running mixed models applied to observational data collected over 1 year on adult (>16 years old) human subjects. Only social bonding predicted the occurrence, frequency, and latency of yawn contagion. As with other measures of empathy, the rate of contagion was greatest in response to kin, then friends, then acquaintances, and lastly strangers. Related individuals (r?0.25) showed the greatest contagion, in terms of both occurrence of yawning and frequency of yawns. Strangers and acquaintances showed a longer delay in the yawn response (latency) compared to friends and kin. This outcome suggests that the neuronal activation magnitude related to yawn contagion can differ as a function of subject familiarity. In conclusion, our results demonstrate that yawn contagion is primarily driven by the emotional closeness between individuals and not by other variables, such as gender and nationality. PMID:22163307

Norscia, Ivan; Palagi, Elisabetta

2011-12-07

181

Restoring Fossil Creek  

ERIC Educational Resources Information Center

|Fossil Creek had been dammed for the past 90 years, and plans were underway to restore the stream. The creek runs through Central Arizona and flows from the high plateaus to the desert, cutting through the same formations that form the Grand Canyon. This article discusses the Fossil Creek monitoring project. In this project, students and teachers…

Flaccus, Kathleen; Vlieg, Julie; Marks, Jane C.; LeRoy, Carri J.

2004-01-01

182

Fossil Dig Site  

NSDL National Science Digital Library

In this activity (located on page 5 of PDF), learners work in groups to create dig sites for display. Learners arrange dry, uncooked pasta "bones" to resemble dinosaur fossils on a foam tray of wet soil. Use this activity to introduce learners to dinosaur anatomy, dig sites, fossils, and paleontology in general.

Museum, Chicago C.

2011-01-01

183

Dinosaur Footprints & Fossils  

NSDL National Science Digital Library

In this activity, early learners simulate fossil prints in play dough or clay. Using plastic dinosaur feet to make footprints on their âmudâ (much as dinosaurs walked around their habitat) and harvest items (leaves, corn, twigs, acorns) to make impressions, learners simulate fossil prints. This resource includes open-ended discussion questions to encourage reflection.

Omsi

2004-01-01

184

Becoming a Fossil  

NSDL National Science Digital Library

This text and accompanying video provide an overview of how fossils are formed and preserved. A video clip from the NOVA television program, 'In Search of Human Origins', shows how the famous early hominid 'Lucy' might have died and been fossiliized, and points out the rare set of circumstances that must occur for an organism to be fossilized. Questions for discussion are included.

2005-01-01

185

Restoring Fossil Creek  

ERIC Educational Resources Information Center

Fossil Creek had been dammed for the past 90 years, and plans were underway to restore the stream. The creek runs through Central Arizona and flows from the high plateaus to the desert, cutting through the same formations that form the Grand Canyon. This article discusses the Fossil Creek monitoring project. In this project, students and teachers…

Flaccus, Kathleen; Vlieg, Julie; Marks, Jane C.; LeRoy, Carri J.

2004-01-01

186

Trace Fossil Image Database  

NSDL National Science Digital Library

This database from Emory University consists of images and basic information concerning trace fossils photographed by Anthony Martin. Included in this information is the formation, age, and locality of the specimen if known. Many of the images were originally photographed while in the field, and each type of trace fossil has numerous examples to browse through.

Martin, Anthony; University, Emory

187

Fossil energy program  

NASA Astrophysics Data System (ADS)

Research and development programs in support of the increased utilization of coal and other fossil fuel alternatives as sources of clean energy are reported. The following projects are reported: coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction, process analysis and engineering evaluations, fossil energy environmental analysis, environmental control technology, coal preparation waste utilization, atmospheric fluidized bed coal combustor for cogeneration, TVA FBC demonstration plant program technical support, PFBC systems analysis, FBC char utilization improvement, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology, generalized equilibrium models for liquid and gaseous fuel supplies, analysis of coal production, and fossil energy information center.

McNeese, L. E.

1981-12-01

188

The size of scalable brain components in the human evolutionary lineage: with a comment on the paradox of Homo floresiensis.  

PubMed

The discovery of a diminutive, small-brained hominin skeleton (LB1) from the Pleistocene of Flores, Indonesia, seems to present a paradox concerning the interpretation of overall brain size in an evolutionary context. This specimen forms the holotype of a purportedly new hominin species, Homo floresiensis. As inferred from the archaeological record, it has been suggested that this species of Homo, existing as recently as 12,000 years ago, engaged in sophisticated cultural behaviors with an adult brain size equivalent to that seen in modern chimpanzees and one that in modern humans would be defined as "high degree microcephaly" and "always associated with idiocy". The alternative explanation for these behaviors at the observed brain size would require that H. floresiensis deviate from existing patterns of primate brain scaling at either a macroscopic or microscopic level. Here we develop predictive equations and confidence intervals for estimating the size of various brain components in the human evolutionary lineage by calculating scaling relationships among overall brain size and 11 components of the primate brain using phylogenetically independent contrasts (PIC) methods. Using these equations, paleoanthropologists can: (a) estimate brain component size (and confidence intervals) for any primate in the fossil record if overall brain size is known; and (b) calculate some reasonable outside limits as to how far species-specific departures from allometric constraints (i.e., brain "reorganization") can be taken in assessing human brain evolution. We conclude that if the original assessment of LB1 is correct, i.e., that it samples a population from a new species of Homo, H. floresiensis, that was capable of Homo sapiens-like cultural attributes (fire, blade manufacturing, etc.), while having a chimpanzee-sized brain, then we are faced with the paradox that 1 cm(3) of H. floresiensis brain could not be functionally equivalent to 1cm(3) of a modern human or modern chimpanzee brain. PMID:17240374

Conroy, G C; Smith, R J

2007-01-22

189

Fossil fuels -- future fuels  

SciTech Connect

Fossil fuels -- coal, oil, and natural gas -- built America`s historic economic strength. Today, coal supplies more than 55% of the electricity, oil more than 97% of the transportation needs, and natural gas 24% of the primary energy used in the US. Even taking into account increased use of renewable fuels and vastly improved powerplant efficiencies, 90% of national energy needs will still be met by fossil fuels in 2020. If advanced technologies that boost efficiency and environmental performance can be successfully developed and deployed, the US can continue to depend upon its rich resources of fossil fuels.

NONE

1998-03-01

190

Fossil energy program  

NASA Astrophysics Data System (ADS)

The projects reported include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation studies, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, flue gas desulfurization, plant control development, atmospheric fluidized bed coal combustor for cogeneration, TVA, FBC demonstration plant program technical support, and PFBC systems analysis. Fossil fuel application assessments, performance assurance system support for fossil energy projects, international energy technology assessment, and general equilibrium models of liquid and gaseous fuel supplies are presented.

McNeese, L. E.

1981-02-01

191

Patterning of geographic variation in Middle Pleistocene Homo frontal bone morphology.  

PubMed

A quantitative assessment of the frontal bone morphology of a sample of Middle Pleistocene hominins was undertaken in order to address questions regarding their population structure and evolutionary history. Outline tracings of the frontal bones of forty-seven fossil crania were obtained, and size-standardized measurements were then computed using an Elliptical Fourier analysis of these tracings. Principal component scores of the Fourier harmonic amplitudes were derived and served as a quantitative representation of the morphology of the frontal bone. Morphological, geographical, and temporal distance matrices were then constructed between each pair of fossils. A partial Mantel matrix correlation test was performed between morphological and geographical distance matrices, controlling for temporal distance, in order to determine if the pattern of geographical differentiation in features of the frontal bone of mid-Pleistocene Homo followed that of an isolation-by-distance model of population structure. The results of the partial Mantel tests indicate that the overall patterning of differentiation in the features of the frontal bone cannot best be explained by a population structure shaped by isolation-by-distance. Additionally, various aspects of the frontal bone quantified here follow different patterns of geographical differentiation, suggesting that a mosaic pattern of evolution holds true for characters within one cranial region and not just for those between regions. PMID:16678885

Athreya, Sheela

2006-05-05

192

The calvaria of Sangiran 38, Sendangbusik, Sangiran Dome, Java.  

PubMed

We describe in detail Sangiran 38 (S38), an adult partial calvaria recovered in 1980 from the Bapang (Kabuh) Formation of the Sangiran Dome near the hamlet of Sendangbusik, Java. Several other hominins (Bukuran, Hanoman 1, and Bs 9706) recovered in the vicinity come from either the upper-most Sangiran (Pucangan) or lower-most Bapang formations. S38 is from the lower Bapang Formation, which (40)Ar/(39)Ar age estimates suggest spans between 1.47 and 1.58Ma. Anatomical and metric comparisons with a worldwide set of 'early non-erectus'Homo, and Homo erectus (sensu lato) fossils indicate S38 is best considered a member of H. erectus. Although smaller in size, S38 is similar in overall morphology to the Bukuran specimen of similar age and provenance. The S38 calvaria exhibits several depressed lesions of the vault consistent with a scalp or systemic infection or soft tissue cyst. PMID:20638657

Indriati, Etty; Antón, Susan C

2010-08-01

193

Fossilized Dinosaur Bones  

NSDL National Science Digital Library

This slide show presents images of dinosaur bones and shows paleotologists at work excavating and preserving these fossils, the best evidence remaining of these long-lost creatures. A background essay and discussion questons are included.

194

Minerals and Fossils  

NSDL National Science Digital Library

This site is dedicated to rock and mineral collecting. It contains information for worldwide mineral and fossil collectors with articles, mineral photos, videos, a search engine and free classified ads.

Mineraltown.com

195

Fossil energy program  

NASA Astrophysics Data System (ADS)

A compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives as sources of clean energy is presented. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction projects, process analysis; and engineering evaluations, fossil energy environmental analysis, flue gas desulfurization, solid waste disposal, coal preparation and waste utilization, plant control development, atmospheric fluidized bed coal combustor for cogeneration, Tennessee Valley Authority Fluidized Bed Combustion demonstration plant program technical support, PFBC systems analysis, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology assessment, and generalized equilibrium models of liquid and gaseous fuel supplies.

McNeese, L. E.

1981-03-01

196

Fossil energy program  

NASA Astrophysics Data System (ADS)

The progress made during the period from July 1 through September 30 for the Oak Ridge National Laboratory research and development projects in support of the increased utilization of coal and other fossil fuels as sources of clean energy is reported. The following topics are discussed: coal conversion development, chemical research and development, materials technology, fossil energy materials program, liquefaction projects, component development, process analysis, environmental control technology, atmospheric fluidized bed combustion, underground coal gasification, coal preparation and waste utilization.

McNeese, L. E.

1981-12-01

197

The Great Fossil Find  

NSDL National Science Digital Library

In this imaginary fossil hunt, students learn about the uncertainty of science and the fact that, as new evidence is revealed, ideas may change. As they follow a script read by the teacher, students find (remove from envelope) paper fossils of some unknown creature, a few at a time. Each time, they attempt to reconstruct the creature and each time their interpretation tends to change as new pieces are found.

198

Is Homo heidelbergensis a distinct species? New insight on the Mauer mandible.  

PubMed

The discovery of new fossils in Africa, Asia, and Europe, and the recognition of a greater diversity in the middle Pleistocene fossil record, has led to a reconsideration of the species Homo heidelbergensis. This nomen, formulated by Schoetensack in 1908 to describe the Mauer jaw (Germany), was almost forgotten during most of the past century. Numerous fossils have been attributed to it but no consensus has arisen concerning their classification. The holotype anatomical traits are still poorly understood, and numerous fossils with no mandibular remains have been placed in the taxon. Some researchers propose H. heidelbergensis as an Afro-European taxon that is ancestral to both modern humans and Neandertals whereas others think it is a strictly European species that is part of the Neandertal lineage. We focus on the validity of H. heidelbergensis, using the traditional basis of species recognition: anatomical description. We provide a comparative morphological analysis using 47 anatomical traits of 36 Pleistocene fossils from Africa, Asia, and Europe and 35 extant human mandibles. We re-examine the mandibular features of Mauer and discuss the specimen's inclusion in H. heidelbergensis, as well as alternative evolutionary theories. To lend objectivity to specimen grouping, we use multiple correspondence analysis associated with hierarchical classification that creates clusters corresponding to phenetic similarities between jaws. Our phenetic and comparative morphological analyses support the validity of H. heidelbergensis as a taxon. A set of morphological features can be statistically identified for the definition of the species. Some traits can be used to delimit H. heidelbergensis in an evolutionary framework (e.g., foramina mentale posteriorly positioned, horizontal retromolar surface). Those traits are also present on African (e.g., Tighenif) and European (e.g., Sima de los Huesos) specimens that show a close relationship with the Mauer mandible. Therefore, the definition of H. heidelbergensis is more precise and mainly supports the theory of an Afro-European taxon, which is the last common ancestor of H. neanderthalensis and H. sapiens. However, the results of this study fail to entirely discount the hypothesis that considers H. heidelbergensis as a chronospecies leading to the Neandertals. PMID:19249816

Mounier, Aurélien; Marchal, François; Condemi, Silvana

2009-02-27

199

Trace Fossil Analysis  

NASA Astrophysics Data System (ADS)

Today, the study of trace fossils—ichnology—is an important subdiscipline of geology at the interface of paleontology and sedimentology, mostly because of the efforts of Adolf Seilacher. His ability to synthesize various aspects of ichnology and produce a hierarchy of marine ichna and sedimentary facies has made ichnology useful worldwide in interpreting paleodiversity, rates of sedimentation, oxygenation of bottom water and sediment pore water, and depositional energy. Seilacher's book Trace Fossil Analysis provides a glimpse into the mind, methodology, and insights of the father of modern ichnology, generated from his course notes as a professor and a guest lecturer. The title sounds misleading—readers looking for up-to-date principles and approaches to trace fossil analysis in marine and continental strata will be disappointed. In his preface, however, Seilacher clearly gives direction for the use of his text: “This is a course book—meaning that it is intended to confer not knowledge, but skill.” Thus, it is not meant as a total compilation of all trace fossils, ichnotaxonomy, ichnological interpretations, applications, or the most relevant and up-to-date references. Rather, it takes the reader on a personal journey, explaining how trace fossils are understood in the context of their three-dimensional (3-D) morphology and sedimentary facies.

Hasiotis, Stephen T.

2009-05-01

200

Fossilization of feathers  

NASA Astrophysics Data System (ADS)

Scanning electron microscopy of feathers has revealed evidence that a bacterial glycocalyx (a network of exocellular polysaccharide fibers) played a role in promoting their fossilization in some cases. This mode of preservation has not been reported in other soft tissues. The majority of fossil feathers are preserved as carbonized traces. More rarely, bacteria on the surface are replicated by authigenic minerals (bacterial autolithification). The feathers of Archaeopteryx are preserved mainly by imprintation following early lithification of the substrate and decay of the feather. Lacustrine settings provide the most important taphonomic window for feather preservation. Preservation in terrestrial and normal-marine settings involves very different processes (in amber and in authigenically mineralized coprolites, respectively). Therefore, there may be a significant bias in the avian fossil record in favor of inland water habitats.

Davis, Paul G.; Briggs, Derek E. G.

1995-09-01

201

The Fossil Record  

NSDL National Science Digital Library

This lesson plan is part of the DiscoverySchool.com lesson plan library for grades 9-12. It centers around fossils found in the Burgess Shale in western Canada. Topics include body shapes of fossils found, the movement of organisms from oceans to land, and whether organisms existed that did not fossilize. This part of geologic history began in the Cambrian Sea about 540 million years ago. The resource includes objectives, materials, procedures, discussion questions, evaluation ideas, extensions, suggested readings, and vocabulary. There are videos available to order which complement this lesson, an audio-enhanced vocabulary list, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

Wu, Lisa

202

Earliest human occupations at Dmanisi (Georgian Caucasus) dated to 1.85-1.78 Ma  

PubMed Central

The early Pleistocene colonization of temperate Eurasia by Homo erectus was not only a significant biogeographic event but also a major evolutionary threshold. Dmanisi's rich collection of hominin fossils, revealing a population that was small-brained with both primitive and derived skeletal traits, has been dated to the earliest Upper Matuyama chron (ca. 1.77 Ma). Here we present archaeological and geologic evidence that push back Dmanisi's first occupations to shortly after 1.85 Ma and document repeated use of the site over the last half of the Olduvai subchron, 1.85–1.78 Ma. These discoveries show that the southern Caucasus was occupied repeatedly before Dmanisi's hominin fossil assemblage accumulated, strengthening the probability that this was part of a core area for the colonization of Eurasia. The secure age for Dmanisi's first occupations reveals that Eurasia was probably occupied before Homo erectus appears in the East African fossil record.

Ferring, Reid; Oms, Oriol; Agusti, Jordi; Berna, Francesco; Nioradze, Medea; Shelia, Teona; Tappen, Martha; Vekua, Abesalom; Zhvania, David; Lordkipanidze, David

2011-01-01

203

Earliest human occupations at Dmanisi (Georgian Caucasus) dated to 1.85-1.78 Ma.  

PubMed

The early Pleistocene colonization of temperate Eurasia by Homo erectus was not only a significant biogeographic event but also a major evolutionary threshold. Dmanisi's rich collection of hominin fossils, revealing a population that was small-brained with both primitive and derived skeletal traits, has been dated to the earliest Upper Matuyama chron (ca. 1.77 Ma). Here we present archaeological and geologic evidence that push back Dmanisi's first occupations to shortly after 1.85 Ma and document repeated use of the site over the last half of the Olduvai subchron, 1.85-1.78 Ma. These discoveries show that the southern Caucasus was occupied repeatedly before Dmanisi's hominin fossil assemblage accumulated, strengthening the probability that this was part of a core area for the colonization of Eurasia. The secure age for Dmanisi's first occupations reveals that Eurasia was probably occupied before Homo erectus appears in the East African fossil record. PMID:21646521

Ferring, Reid; Oms, Oriol; Agustí, Jordi; Berna, Francesco; Nioradze, Medea; Shelia, Teona; Tappen, Martha; Vekua, Abesalom; Zhvania, David; Lordkipanidze, David

2011-06-06

204

The Homo Zappiens and its Consequences for Learning in Universities  

NASA Astrophysics Data System (ADS)

Homo Zappiens is the new generation that is growing up with modern communication technologies shaping their views on the world around them. Prominent characteristics of Homo Zappiens include their preference for images and symbols as an enrichment of plain text, their seemingly effortless adoption of technology, and their cooperation and sharing in networks. They use technology in a functional manner, not touching what they cannot use, and increasingly this generation seems to take exploration and learning and discovering the world, into their own hands. Homo Zappiens shows us that we can increasingly rely on technology to connect us and allow us to organize and preserve our society as a group. In a networked society, the individual has more room for contributing his/her unique value, and innovation and knowledge reside in a network, rather than in each separate individual. Higher education institutions will evolve towards institutions that will function as hubs in knowledge networks, serving students working in fluid communities of research or learning on subjects of their interest. Realizing that we need a flexible structure for organizing ourselves and the world around us, we can look at Homo Zappiens for a clue.

Veen, Wim; van Staalduinen, Jan-Paul

205

Fossil energy program  

NASA Astrophysics Data System (ADS)

Progress is reported for the period July 1 through September 30 for the Oak Ridge National Laboratory research and development projects that are carried out in support of the increased utilization of coal and other fossil fuels as sources of clean energy. These projects are supported by various parts of DOE including Fossil Energy, Basic Energy Sciences, Office of Health and Environmental Research, Office of Environmental Compliance and Overview, Economic Regulatory Administration, Power Research Institute, and by the Tennessee Valley Authority and the EPA Office of Research and Development through interagency agreements

McNeese, L. E.

1981-01-01

206

Science Sampler : Fossil detectives  

NSDL National Science Digital Library

Middle school students are transformed into Fossil detectives as they examine the fossil record and use evidence about paleo-environments to develop an understanding of structure and function in living systems and changes over time in Earths history. In this enrichment activity, students work in teams to research an assigned geologic time period. They determine available habitats, food sources and types (animal, plant; woody, herbaceous, etc.), cover sources, methods of getting food, defense, and reproduction that would allow an animal to live in the assigned paleoenvironment. In culmination of their efforts, students create a diorama to display their findings.

Bourdeau, Virginia

2006-01-01

207

What is a Fossil?  

NSDL National Science Digital Library

In this activity about dinosaurs, learners explore how and why fossils form. First, learners are introduced to dinosaur fossils by reading the book "Bones, Bones, Dinosaur Bones" by Byron Barton. Then, learners make impressions in clay using a seashell, pennies, dinosaur teeth and other items. Next, learners make dinosaur tracks in the clay as they "walk" plastic models across the soft clay. Learners also use sponges pre-cut in the shape of dinosaur feet to make more tracks. This activity is featured on page 29 of the "Dinosphere" unit of study for K-2 learners.

Crosslin, Rick; Fortney, Mary; Indianapolis, The C.

2004-01-01

208

Controlled Dimerization of ErbB Receptors Provides Evidence for Differential Signaling by Homo and Heterodimers  

Microsoft Academic Search

The four members of the ErbB family of receptor tyrosine kinases are involved in a complex array of combinatorial interactions involving homo- and heterodimers. Since most cell types express more than one member of the ErbB family, it is difficult to distinguish the biological activities of different homo- and heterodimers. Here we describe a method for inducing homo- or heterodimerization

SENTHIL K. MUTHUSWAMY; MICHAEL GILMAN; JOAN S. BRUGGE

1999-01-01

209

The Astonishing Micropygmies  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. The stunning discovery of a Late Pleistocene hominin skeleton, on the Indonesian island of Flores has thrown the anthropological world into a frenzy. The primitive and derived features of the skeleton, but most curiously its tiny stature suggest a new species of diminutive Homo erectus called H. floresiensis. In a provocative Perspective, Jared Diamond provides a scintillating synthesis of the evidence for a new H. erectus species and debates the reasons why the fossil remains of this pygmy hominin have only now been discovered.

Jared Diamond (University of California at Los Angeles;Geography Department)

2004-12-17

210

Fossilization of Acidophilic Microorganisms  

Microsoft Academic Search

This study examines fossil microorganisms found in iron-rich deposits in an extreme acidic environment, the Tinto River in SW Spain. Both electron microscopy (SEM and TEM) and non-destructive in situ microanalytical techniques (EDS, EMP and XPS) were used to determine the role of permineralization and encrustation in preserving microorganisms forming biofilms in the sediments. Unicellular algae were preserved by silica

Virginia Souza-Egipsy; Angeles Aguilera; Eva Mateo-Martí; José Angel Martín-Gago; Ricardo Amils

2010-01-01

211

Fossil Halls: Virtual Tours  

NSDL National Science Digital Library

Part of a larger online look at the Museum's famed Fossil Halls, this Web site has an overview of the halls' many highlights and four QuickTime virtual tours:Hall of Saurischian Dinosaurs, Hall of Ornithischian Dinosaurs, Hall of Primitive Mammals, and Hall of Advanced Mammals.

212

Fossil Evidence of Bipedalism  

NSDL National Science Digital Library

This video segment adapted from NOVA shows how scientists use the fossil record to trace when early human ancestors and related species began walking on two legs instead of four, and to determine whether they were more apelike or human in appearance.

Foundation, Wgbh E.

2010-04-05

213

Fossils and Minerals  

NSDL National Science Digital Library

This site from the Black Hills Institute features information about different types of fossils, minerals, meteorites, and geology in general. Each topic has a brief description, with links to a more detailed explanation. Various samples and books are abailable for purchase on the site.

Research, Inc. B.

214

Advanced fossil energy utilization  

SciTech Connect

This special issue of Fuel is a selection of papers presented at the symposium ‘Advanced Fossil Energy Utilization’ co-sponsored by the Fuels and Petrochemicals Division and Research and New Technology Committee in the 2009 American Institute of Chemical Engineers (AIChE) Spring National Meeting Tampa, FL, on April 26–30, 2009.

Shekhawat, D.; Berry, D.; Spivey, J.; Pennline, H.; Granite, E.

2010-01-01

215

Rethinking Fossil Fuels  

NSDL National Science Digital Library

Climate change and fossil fuel use are connected. It would serve the world well to: begin a moratorium on coal-fired power plants; explore and use renewable energy; insist on immediate action from world governments; and penalize industries putting excess CO2 into the atmosphere.

James Hansen (NASA Goddard Institute for Space Studies;)

2008-09-09

216

A Fossil Buttercup  

Microsoft Academic Search

WHEN we examine a catalogue of fossil plants, such as that for North America recently published by Knowlton, we are struck by the enormous number of recorded species, and readily receive the impression that the flora of former ages is quite well known. It is only when we make a more critical investigation that we perceive the great gap in

T. D. A. Cockerell

1922-01-01

217

Centering on Fossils and Dinosaurs.  

ERIC Educational Resources Information Center

|Describes a set of 10 activities which introduce mainstreamed junior high school students to concepts relating to fossils and dinosaurs. Provides students with opportunities for learning the concepts of change and adaptation, as well as fossil facts and terminology. (TW)|

Coble, Charles R.; McCall, Gregory K.

1986-01-01

218

Teacher's Domain: Fun with Fossils  

NSDL National Science Digital Library

Fossils provide a valuable record of the plant and animal life and environmental conditions from millions, even billions of years ago. In this lesson, students create their own fossils, and then use multimedia resources to learn how real fossils form and what scientists can learn from them. They should understand that fossils provide evidence of plants and animals that lived long ago, as well as the environmental conditions at that time. Instructions, a materials list, and links to multimedia resources are provided.

2005-01-01

219

Fossil Energy: Drivers and Challenges  

Microsoft Academic Search

Concerns about rapid economic growth, energy security, and global climate change have created a new landscape for fossil energy exploration, production, and utilization. Since 85% of primary energy supply comes from fossil fuels, and 85% of greenhouse gas emissions come from fossil fuel consumption, new and difficult technical and political challenges confront commercial, governmental, and public stakeholders. As such, concerns

Julio Friedmann

2007-01-01

220

New hominid fossils from Member 1 of the Swartkrans formation, South Africa.  

PubMed

Member 1 of the Swartkrans Formation is comprised of two sedimentary infills, the Lower Bank (LB) and the Hanging Remnant (HR). Together, the LB and HR preserve fossils of early Homo and Paranthropus robustus, Earlier Stone Age lithic artifacts, purported bone digging tools and butchered animal bones. Collectively, this evidence was the first to establish the co-existence of two early Pleistocene hominid species and also led to inferences of plant root harvesting and meat-eating by one or both of those species. P. robustus is the more abundant of the two hominids at Swartrkrans, represented in Member 1 by hundreds of fossils that derive from at least 99 individuals. Thus, Swartkrans Member 1 stands as the world's single largest repository of that extinct species. Here we add to the Member 1 sample of hominid fossils with descriptions of 14 newly discovered specimens. PMID:22440747

Pickering, Travis Rayne; Heaton, Jason L; Clarke, Ronald J; Sutton, Morris B; Brain, C K; Kuman, Kathleen

2012-03-21

221

Fossil Microbes on Mars?  

NSDL National Science Digital Library

This online article, from Cosmic Horizons: Astronomy at the Cutting Edge, reports on the controversial discovery of Martian meteorite ALH84001. In 1996, a team of scientists led by David McKay of NASAâs Johnson Space Flight Center announced that they had discovered evidence for microscopic fossil life in this meteorite from Mars. From the start, the evidence was both fascinating and controversial, and to this day it remains so.

222

Mesosaurus Fossil Site  

NSDL National Science Digital Library

This article describes the occurrence and habits of Mesosaurus, a small marine reptile that lived during the late Carboniferous and early Permian periods, as seen at a site in Namibia. Topics include the distribution of Mesosaurus fossils in both African and South American rock formations (evidence of continental drift), the shallow sea habitats in which Mesosuarus existed 280 to 320 million years ago, and some of its postulated living habits.

223

Fossil Age Estimation Model  

NSDL National Science Digital Library

In this activity (page 1 of the PDF), learners will model how paleontologists estimate the age of fossil discoveries by extracting âfossilâ playing cards from newspapers stacked in chronological order. Learners identify the âageâ of the card based on the âevidenceâ (printed date) in the surrounding pages. They then create a data table and graph and analyze their findings. Use this activity to introduce learners to paleontology and geology. Relates to the linked video, DragonflyTV GPS: Dinosaurs.

Twin Cities Public Television, Inc.

2006-01-01

224

Fossil Halls: Timelines  

NSDL National Science Digital Library

Part of a larger virtual tour of the Museum's famed Fossil Halls, this Web site allows students to travel back in time to several prehistoric points in the history of Earth. At each, they'll find a fleshed-out portrait of the period's creatures and their environment. The eight periods students will visit, some of which include more than one point-in-time snapshot, are Pleistocene, Miocene, Oligocene, Eocene, Cretaceous, Jurassic, Permian and Devonian Periods.

225

Bibliography of Fossil Vertebrates  

NSDL National Science Digital Library

The Society of Vertebrate Paleontology (SVP), one of most reputable American paleontological societies, sponsors this online edition of its Bibliography of Fossil Vertebrates. The database, which currently covers the years 1509-1958 and 1981-1993 with approximately 112,000 references, is searchable by author, subject, taxon, language, editor, and journal book or volume title. A help page with query instructions for the somewhat finicky search engine is provided.

1997-01-01

226

The Unknown Fossil Report  

NSDL National Science Digital Library

This project challenges the students ingenuity, creativity, and resourcefulness! They each receive a fossil of unknown identity (general geographic locality may be given, e.g., I-55 south of St. Louis, MO). The specimen is described in as much detail as possible. Their report should include taxonomic classification (as complete as they can), age, paleoecology, Earth history, and other interpretations they can infer. Identification may require library work, Internet search, etc.

Reams, Max W.

227

Fossils, feet and the evolution of human bipedal locomotion  

PubMed Central

We review the evolution of human bipedal locomotion with a particular emphasis on the evolution of the foot. We begin in the early twentieth century and focus particularly on hypotheses of an ape-like ancestor for humans and human bipedal locomotion put forward by a succession of Gregory, Keith, Morton and Schultz. We give consideration to Morton's (1935) synthesis of foot evolution, in which he argues that the foot of the common ancestor of modern humans and the African apes would be intermediate between the foot of Pan and Hylobates whereas the foot of a hypothetical early hominin would be intermediate between that of a gorilla and a modern human. From this base rooted in comparative anatomy of living primates we trace changing ideas about the evolution of human bipedalism as increasing amounts of postcranial fossil material were discovered. Attention is given to the work of John Napier and John Robinson who were pioneers in the interpretation of Plio-Pleistocene hominin skeletons in the 1960s. This is the period when the wealth of evidence from the southern African australopithecine sites was beginning to be appreciated and Olduvai Gorge was revealing its first evidence for Homo habilis. In more recent years, the discovery of the Laetoli footprint trail, the AL 288-1 (A. afarensis) skeleton, the wealth of postcranial material from Koobi Fora, the Nariokotome Homo ergaster skeleton, Little Foot (Stw 573) from Sterkfontein in South Africa, and more recently tantalizing material assigned to the new and very early taxa Orrorin tugenensis, Ardipithecus ramidus and Sahelanthropus tchadensis has fuelled debate and speculation. The varying interpretations based on this material, together with changing theoretical insights and analytical approaches, is discussed and assessed in the context of new three-dimensional morphometric analyses of australopithecine and Homo foot bones, suggesting that there may have been greater diversity in human bipedalism in the earlier phases of our evolutionary history than previously suspected.

Harcourt-Smith, W E H; Aiello, L C

2004-01-01

228

Fossils, feet and the evolution of human bipedal locomotion.  

PubMed

We review the evolution of human bipedal locomotion with a particular emphasis on the evolution of the foot. We begin in the early twentieth century and focus particularly on hypotheses of an ape-like ancestor for humans and human bipedal locomotion put forward by a succession of Gregory, Keith, Morton and Schultz. We give consideration to Morton's (1935) synthesis of foot evolution, in which he argues that the foot of the common ancestor of modern humans and the African apes would be intermediate between the foot of Pan and Hylobates whereas the foot of a hypothetical early hominin would be intermediate between that of a gorilla and a modern human. From this base rooted in comparative anatomy of living primates we trace changing ideas about the evolution of human bipedalism as increasing amounts of postcranial fossil material were discovered. Attention is given to the work of John Napier and John Robinson who were pioneers in the interpretation of Plio-Pleistocene hominin skeletons in the 1960s. This is the period when the wealth of evidence from the southern African australopithecine sites was beginning to be appreciated and Olduvai Gorge was revealing its first evidence for Homo habilis. In more recent years, the discovery of the Laetoli footprint trail, the AL 288-1 (A. afarensis) skeleton, the wealth of postcranial material from Koobi Fora, the Nariokotome Homo ergaster skeleton, Little Foot (Stw 573) from Sterkfontein in South Africa, and more recently tantalizing material assigned to the new and very early taxa Orrorin tugenensis, Ardipithecus ramidus and Sahelanthropus tchadensis has fuelled debate and speculation. The varying interpretations based on this material, together with changing theoretical insights and analytical approaches, is discussed and assessed in the context of new three-dimensional morphometric analyses of australopithecine and Homo foot bones, suggesting that there may have been greater diversity in human bipedalism in the earlier phases of our evolutionary history than previously suspected. PMID:15198703

Harcourt-Smith, W E H; Aiello, L C

2004-05-01

229

Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment  

SciTech Connect

In 1994 we initiated a long-term field experiment in a calcareous grassland to study the effects of elevated CO{sub 2} on individuals, populations, and communities. Clonal replicates of 54 genotypes of the dominant grass Bromus erectus were grown in communities planted at three levels of biodiversity (5-, 12-, 31-species plots) and exposed to ambient and elevated CO{sub 2}. The same genotypes were also individually grown in tubes within the field plots. Some genotypes were infected by the endophytic fungus Epichloee typhina. Elevated CO{sub 2} had no significant effects on plant growth, however, there was large variation among genotypes in all measured characters. A significant CO{sub 2}-by-genotype interaction was found for leaf length in the competition-free tubes. Infection by the endophyte led to the abortion of all inflorescences but increased vegetative growth, especially under competitive conditions.

Steinger, T.; Groppe, K.; Schmid, B. [Univ. of Basel (Switzerland)]|[Univ. of Zurich (Switzerland)

1995-06-01

230

Homo sapiens, Homo neanderthalensis and the Denisova specimen: New insights on their evolutionary histories using whole-genome comparisons.  

PubMed

After a brief review of the most recent findings in the study of human evolution, an extensive comparison of the complete genomes of our nearest relative, the chimpanzee (Pan troglodytes), of extant Homo sapiens, archaic Homo neanderthalensis and the Denisova specimen were made. The focus was on non-synonymous mutations, which consequently had an impact on protein levels and these changes were classified according to degree of effect. A total of 10,447 non-synonymous substitutions were found in which the derived allele is fixed or nearly fixed in humans as compared to chimpanzee. Their most frequent location was on chromosome 21. Their presence was then searched in the two archaic genomes. Mutations in 381 genes would imply radical amino acid changes, with a fraction of these related to olfaction and other important physiological processes. Eight new alleles were identified in the Neanderthal and/or Denisova genetic pools. Four others, possibly affecting cognition, occured both in the sapiens and two other archaic genomes. The selective sweep that gave rise to Homo sapiens could, therefore, have initiated before the modern/archaic human divergence. PMID:23413113

Paixão-Côrtes, Vanessa Rodrigues; Viscardi, Lucas Henrique; Salzano, Francisco Mauro; Hünemeier, Tábita; Bortolini, Maria Cátira

2012-12-18

231

Fossilized Dinosaur Teeth Adaptations  

NSDL National Science Digital Library

In this activity, learners use models of fossilized dinosaur teeth to understand how dinosaur teeth were used. Learners specifically research Tyrannosaurus rex and Triceratops horridus dinosaurs and determine that Triceratops teeth work the way pliers and scissors operate, and T. rex teeth are like sharp knives. Learners match and sort dinosaurs by the type and use of their teeth. This activity is featured on pp.14-18 (part of a lesson that begins on p.7) of the "Dinosphere" unit of study for grades 3-5.

Crosslin, Rick; Fortney, Mary; Indianapolis, The C.

2004-01-01

232

Fossil Mammal Research Group  

NSDL National Science Digital Library

This website presents the Fossil Mammal Research Group whose "members are palaeontologists and archaeologists as well as palaeoenvironmental specialists in the School of Biological & Earth Sciences, Liverpool John Moores University, UK." Subjects of study by the Research group include mammalian fauna development over the past 30 million years, Plio-Pleistocene and Holocene climate change, and more. The website links to subpages for a list of Publications from 1998-2004, Major Projects going on around the world, Conferences, and relevant links. The site also provides a page presenting group members along with their research interests and email addresses.

233

Geochemical trends through time and lateral variability of diatom floras in the Pleistocene Olorgesailie Formation, southern Kenya Rift Valley  

Microsoft Academic Search

The Olorgesailie Formation (1.2–0.49Ma) consists of fluvial and lacustrine rift sediments that have yielded abundant Acheulean artifacts and a fossil hominin (Homo cf. erectus). In testing prior understandings of the paleoenvironmental context, we define nine new geochemical zones. A Chemical Index of Alteration suggests increased catchment weathering during deposition of Members 1, 2, 7, 11, and 13. Biophile elements (Br,

R. B. Owen; R. W. Renaut; R. Potts; A. K. Behrensmeyer

2011-01-01

234

Fossils 2: Uncovering the Facts  

NSDL National Science Digital Library

In Fossils and Dinosaurs, the first lesson of this two lesson series, students learned the differences between facts and ideas that are extrapolated from fossil evidence. This lesson allows students to go through an 'interview' with the remains of a Protoceratops. In preparation for the interview, students first brainstorm the questions they would like answers to, and then narrow their questions to those that can be answered by studying the Protoceratops fossils.

Science Netlinks;

2001-10-20

235

An Enlarged Parietal Foramen in the Late Archaic Xujiayao 11 Neurocranium from Northern China, and Rare Anomalies among Pleistocene Homo  

PubMed Central

We report here a neurocranial abnormality previously undescribed in Pleistocene human fossils, an enlarged parietal foramen (EPF) in the early Late Pleistocene Xujiayao 11 parietal bones from the Xujiayao (Houjiayao) site, northern China. Xujiayao 11 is a pair of partial posteromedial parietal bones from an adult. It exhibits thick cranial vault bones, arachnoid granulations, a deviated posterior sagittal suture, and a unilateral (right) parietal lacuna with a posteriorly-directed and enlarged endocranial vascular sulcus. Differential diagnosis indicates that the perforation is a congenital defect, an enlarged parietal foramen, commonly associated with cerebral venous and cranial vault anomalies. It was not lethal given the individual’s age-at-death, but it may have been associated with secondary neurological deficiencies. The fossil constitutes the oldest evidence in human evolution of this very rare condition (a single enlarged parietal foramen). In combination with developmental and degenerative abnormalities in other Pleistocene human remains, it suggests demographic and survival patterns among Pleistocene Homo that led to an elevated frequency of conditions unknown or rare among recent humans.

Xing, Song

2013-01-01

236

An enlarged parietal foramen in the late archaic Xujiayao 11 neurocranium from Northern China, and rare anomalies among Pleistocene Homo.  

PubMed

We report here a neurocranial abnormality previously undescribed in Pleistocene human fossils, an enlarged parietal foramen (EPF) in the early Late Pleistocene Xujiayao 11 parietal bones from the Xujiayao (Houjiayao) site, northern China. Xujiayao 11 is a pair of partial posteromedial parietal bones from an adult. It exhibits thick cranial vault bones, arachnoid granulations, a deviated posterior sagittal suture, and a unilateral (right) parietal lacuna with a posteriorly-directed and enlarged endocranial vascular sulcus. Differential diagnosis indicates that the perforation is a congenital defect, an enlarged parietal foramen, commonly associated with cerebral venous and cranial vault anomalies. It was not lethal given the individual's age-at-death, but it may have been associated with secondary neurological deficiencies. The fossil constitutes the oldest evidence in human evolution of this very rare condition (a single enlarged parietal foramen). In combination with developmental and degenerative abnormalities in other Pleistocene human remains, it suggests demographic and survival patterns among Pleistocene Homo that led to an elevated frequency of conditions unknown or rare among recent humans. PMID:23527224

Wu, Xiu-Jie; Xing, Song; Trinkaus, Erik

2013-03-18

237

Learning from the Fossil Record  

NSDL National Science Digital Library

Another interesting and helpful resource from the University of California Berkeley Museum of Paleontology is the Learning from the Fossil Record Web site. Educators will find a list of over twenty fossil related classroom activities presented by different authors with titles such as Building a Topographic Model, Determining the Age Of Rocks and Fossils, Fossilization and Adaptation, the Dinosaur Body Structure, Microfossils, and other interesting subjects. The detailed descriptions include everything needed to complete the individual exercises including background information, procedures, and downloads. The unique collection should be a helpful addition to any junior high or high school science curriculum.

1996-01-01

238

Radioactivity in fossils at the Hagerman Fossil Beds National Monument.  

PubMed

Since 1996, higher than background levels of naturally occurring radioactivity have been documented in both fossil and mineral deposits at Hagerman Fossil Beds National Monument in south-central Idaho. Radioactive fossil sites occur primarily within an elevation zone of 900-1000 m above sea level and are most commonly found associated with ancient river channels filled with sand. Fossils found in clay rich deposits do not exhibit discernable levels of radioactivity. Out of 300 randomly selected fossils, approximately three-fourths exhibit detectable levels of natural radioactivity ranging from 1 to 2 orders of magnitude above ambient background levels when surveyed with a portable hand held Geiger-Muller survey instrument. Mineral deposits in geologic strata also show above ambient background levels of radioactivity. Radiochemical lab analysis has documented the presence of numerous natural radioactive isotopes. It is postulated that ancient groundwater transported radioactive elements through sand bodies containing fossils which precipitated out of solution during the fossilization process. The elevated levels of natural radioactivity in fossils may require special precautions to ensure that exposures to personnel from stored or displayed items are kept as low as reasonably achievable (ALARA). PMID:18442873

Farmer, C Neal; Kathren, Ronald L; Christensen, Craig

2008-04-28

239

Speciation in the fossil record  

Microsoft Academic Search

It is easy to claim that the fossil record says nothing about speciation because the biological species concept (which relies on interbreeding) cannot be applied to it and genetic studies cannot be carried out on it. However, fossilized organisms are often preserved in sufficient abundance for populations of intergrading morphs to be recognized, which, by analogy with modern populations, are

Michael J. Benton; Paul N. Pearson

2001-01-01

240

How to Make a Fossil  

NSDL National Science Digital Library

Becoming a fossil is not easy. Most shells or bones decompose or get eaten. This radio broadcast describes how a group of scientists are dropping bags of potential fossils in the ocean to see just what it takes to turn them into stone. The clip is 2 minutes in length.

241

Life of a Vertebrate Fossil  

NSDL National Science Digital Library

Unless you have a very large research grant, it can be difficult to find fossil bones. Fortunately, this very fine online learning module from the Smithsonian's Natural History Museum can help both young and old to learn about locating fossil bones, among other things. Through this multimedia feature created by the History Museum's department of paleobiology, visitors will learn what paleontologists do in each stage in the life of a vertebrate fossil. With the assistance of short video clips, interactive diagrams, and photographs, visitors will learn about how fossils are prepared for examination and how scientists unravel the stories of these paleontological finds. Finally, visitors will also learn how fossils are stored and preserved.

242

Life of a Vertebrate Fossil  

NSDL National Science Digital Library

Unless you have a very large research grant, it can be difficult to find fossil bones. Fortunately, this very fine online learning module from the Smithsonian's Natural History Museum can help both young and old to learn about locating fossil bones, among other things. Through this multimedia feature created by the History Museum's department of paleobiology, visitors will learn what paleontologists do in each stage in the life of a vertebrate fossil. With the assistance of short video clips, interactive diagrams, and photographs, visitors will learn about how fossils are prepared for examination and how scientists unravel the stories of these paleontological finds. Finally, visitors will also learn how fossils are stored and preserved.

2007-09-21

243

Reciprocal evolution of the cerebellum and neocortex in fossil humans  

PubMed Central

Human brain evolution involved both neurological reorganization and an increase in overall brain volume relative to body mass. It is generally difficult to draw functional inferences about the timing and nature of brain reorganization, given that superficial brain morphology recorded on fossil endocasts is functionally ambiguous. However, the cerebellum, housed in the clearly delineated posterior cranial fossa, is functionally and ontologically discrete. The cerebellum is reciprocally connected to each of 14 neocortical regions important to human cognitive evolution. Cerebellar volume varies significantly relative to overall brain volume among mammalian orders, as well as within the primate order. There is also significant diachronic variation among fossil human taxa. In the australopithecines and early members of the genus Homo, the cerebral hemispheres were large in proportion to the cerebellum, compared with other hominoids. This trend continued in Middle and Late Pleistocene humans, including Neandertals and Cro-Magnon 1, who have the largest cerebral hemispheres relative to cerebellum volume of any primates, including earlier and Holocene humans. In recent humans, however, the pattern is reversed; the cerebellum is larger with respect to the rest of the brain (and, conversely, the cerebral hemispheres are smaller with respect to the cerebellum) than in Late Pleistocene humans. The cerebellum and cerebral hemispheres appear to have evolved reciprocally. Cerebellar development in Holocene humans may have provided greater computational efficiency for coping with an increasingly complex cultural and conceptual environment.

Weaver, Anne H.

2005-01-01

244

Fossils as Information  

NASA Astrophysics Data System (ADS)

This book discusses procedures for handling information derived from the fossil record, and the application of this information to solving problems in geological succession and earth history. The main purpose of the book is to analyze shortcomings of the existing procedures, and to propose in their place a new set of data-handling arrangements of much greater simplicity and efficiency. The author argues that the procedures in current use are cumbersome and inefficient, and that, partly as a consequence of these information-handling methods, palaeontology has failed to make advances commensurate with technological improvements. In this book he proposes a fundamentally new system which could make possible the integrated use of every detail of geological information taken from the rocks. This would achieve better resolution in sequence correlation, in paleoecologic interpretation and in logging the course of evolution. Compatibility of style with existing records has been maintained to avoid any danger of loss of valuable data, and to simplify the process of re-evaluating old records. The book will be of interest to all paleontologists, particularly those dealing with microfossils, and is intended to stimulate discussion and criticism of both the analysis and the proposal.

Hughes, Norman Francis

1989-11-01

245

Crystal structure of Homo sapiens protein LOC79017  

SciTech Connect

LOC79017 (MW 21.0 kDa, residues 1-188) was annotated as a hypothetical protein encoded by Homo sapiens chromosome 7 open reading frame 24. It was selected as a target by the Center for Eukaryotic Structural Genomics (CESG) because it did not share more than 30% sequence identity with any protein for which the three-dimensional structure is known. The biological function of the protein has not been established yet. Parts of LOC79017 were identified as members of uncharacterized Pfam families (residues 1-95 as PB006073 and residues 104-180 as PB031696). BLAST searches revealed homologues of LOC79017 in many eukaryotes, but none of them have been functionally characterized. Here, we report the crystal structure of H. sapiens protein LOC79017 (UniGene code Hs.530024, UniProt code O75223, CESG target number go.35223).

Bae, Euiyoung; Bingman, Craig A.; Aceti, David J.; Phillips, Jr., George N. (UW)

2010-02-08

246

Homo Heuristicus: Less-is-More Effects in Adaptive Cognition  

PubMed Central

Heuristics are efficient cognitive processes that ignore information. In contrast to the widely held view that less processing reduces accuracy, the study of heuristics shows that less information, computation, and time can in fact improve accuracy. We discuss some of the major progress made so far, focusing on the discovery of less-is-more effects and the study of the ecological rationality of heuristics which examines in which environments a given strategy succeeds or fails, and why. Homo heuristicus has a biased mind and ignores part of the available information, yet a biased mind can handle uncertainty more efficiently and robustly than an unbiased mind relying on more resource-intensive and general-purpose processing strategies.

Brighton, Henry; Gigerenzer, Gerd

2012-01-01

247

Descriptions of the upper limb skeleton of Homo floresiensis.  

PubMed

Several bones of the upper extremity were recovered during excavations of Late Pleistocene deposits at Liang Bua, Flores, and these have been attributed to Homo floresiensis. At present, these upper limb remains have been assigned to six different individuals - LB1, LB2, LB3, LB4, LB5, and LB6. Several of these bones are complete or nearly so, but some are quite fragmentary. All skeletal remains recovered from Liang Bua were extremely fragile, but have now been stabilized and hardened in the laboratory in Jakarta. They are now curated in museum-quality containers at the National Research and Development Centre for Archaeology in Jakarta, Indonesia. These skeletal remains are described and illustrated photographically. The upper limb presents a unique mosaic of derived (human-like) and primitive morphologies, the combination of which is never found in either healthy or pathological modern humans. PMID:19056103

Larson, S G; Jungers, W L; Tocheri, M W; Orr, C M; Morwood, M J; Sutikna, T; Awe, Rokhus Due; Djubiantono, T

2008-12-04

248

A New Skull of Early Homo from Dmanisi, Georgia  

Microsoft Academic Search

Another hominid skull has been recovered at Dmanisi (Republic of Georgia) from the same strata in which hominid remains have been reported previously. The Dmanisi site dated to ~1.75 million years ago has now produced craniofacial portions of several hominid individuals, along with many well-preserved animal fossils and quantities of stone artifacts. Although there are certain anatomical differences among the

Abesalom Vekua; David Lordkipanidze; G. Philip Rightmire; Jordi Agusti; Reid Ferring; Givi Maisuradze; Alexander Mouskhelishvili; Medea Nioradze; Marcia Ponce de Leon; Martha Tappen; Merab Tvalchrelidze; Christoph Zollikofer

2002-01-01

249

Getting Into the Fossil Record  

NSDL National Science Digital Library

This computer activity provides a basic understanding of what a fossil is and the factors involved in becoming part of the fossil record. It is organized as an informational tour in two sections: one for middle school and one for high school. Students move at a self-selected pace by progressing and answering questions. A teacher's guide contains all necessary instructions as well as lesson plans, handouts, and assessment tools.

Johnson, Jennifer; Lindstrom, Kirsten

250

The legacy of fossil fuels.  

PubMed

Currently, over 80% of the energy used by mankind comes from fossil fuels. Harnessing coal, oil and gas, the energy resources contained in the store of our spaceship, Earth, has prompted a dramatic expansion in energy use and a substantial improvement in the quality of life of billions of individuals in some regions of the world. Powering our civilization with fossil fuels has been very convenient, but now we know that it entails severe consequences. We treat fossil fuels as a resource that anyone anywhere can extract and use in any fashion, and Earth's atmosphere, soil and oceans as a dump for their waste products, including more than 30?Gt/y of carbon dioxide. At present, environmental legacy rather than consistence of exploitable reserves, is the most dramatic problem posed by the relentless increase of fossil fuel global demand. Harmful effects on the environment and human health, usually not incorporated into the pricing of fossil fuels, include immediate and short-term impacts related to their discovery, extraction, transportation, distribution, and burning as well as climate change that are spread over time to future generations or over space to the entire planet. In this essay, several aspects of the fossil fuel legacy are discussed, such as alteration of the carbon cycle, carbon dioxide rise and its measurement, greenhouse effect, anthropogenic climate change, air pollution and human health, geoengineering proposals, land and water degradation, economic problems, indirect effects on the society, and the urgent need of regulatory efforts and related actions to promote a gradual transition out of the fossil fuel era. While manufacturing sustainable solar fuels appears to be a longer-time perspective, alternatives energy sources already exist that have the potential to replace fossil fuels as feedstocks for electricity production. PMID:21290608

Armaroli, Nicola; Balzani, Vincenzo

2011-02-03

251

Numerical description of selected endo- and ectocranial dimensions in Homo sapiens and the three Homo heidelbergensis: Kabwe, Atapuerca and Petralona.  

PubMed

Investigation of hominid cranial morphology is of particular importance for those dealing with questions concerning both ontogenetic and phylogenetic aspects in the genus Homo. The present study provides a numerical description of several regions of extant human crania and, in addition, mid-Pleistocene crania, given in distances and angles. This study is seen as a basic preparatory work that is most useful for further investigation on cranial development in hominids. The sample used consisted of 60 recent adult human crania as well as stereolithographic models of three H. heidelbergensis crania: Kabwe, Atapuerca and Petralona. 12 ecto- and 20 endocranial landmarks were selected and 3D-coordinates taken on each cranium using a 3D Polhemus 3Space FASTRAK tracking system. From the resulting data set, 21 ectocranial and 17 endocranial distances were calculated, in addition to 41 angles of the ectocranium and 21 angles of the endocranium; the measurements are presented in tables, serving as a reference database. PMID:12529956

Bernhard, M; Schäfer, K; Seidler, H

2002-12-01

252

Comparative morphological and morphometric description of the hominin calvaria from Bukuran (Sangiran, Central Java, Indonesia).  

PubMed

We describe the hominin skull (called here "Bukuran") discovered in the lower Kabuh (or "Bapang") series near Sendangbusik, from the Bukuran area in the Sangiran dome. The fossil, heavily mineralized, consists of the parieto-occipital and the left temporal, and the frontal bones. When combined, those two cranial parts represent a rather complete and well-preserved calvaria. Its stratigraphic position was established after the discovery. A detailed description is presented of the morphological and metric features of the Bukuran calvaria, and comparisons are made with Asian Homo erectus from Indonesia and China. The estimated cranial capacity of Bukuran, the general shape of its cranial vault, its ectocranial structures, and its morphological and metrical characters are in the range of Asian Homo erectus, and show clear affinities with other Indonesian members of the species. We discuss the evolutionary status of the Bukuran calvaria and its implication for hominin history on Java. PMID:23021728

Grimaud-Hervé, Dominique; Widianto, Harry; Détroit, Florent; Sémah, François

2012-09-27

253

Place names describing fossils in oral traditions  

Microsoft Academic Search

Folk explanations of notable geological features, including fossils, are found around the world. Observations of fossil exposures (bones, footprints, etc.) led to place names for rivers, mountains, valleys, mounds, caves, springs, tracks, and other geological and palaeonto- logical sites. Some names describe prehistoric remains and\\/or refer to traditional interpretations of fossils. This paper presents case studies of fossil-related place names

ADRIENNE MAYOR

2007-01-01

254

Nucleic acid sensing by an orthogonal reporter system based on homo-DNA  

PubMed Central

We have developed an assay for single strand DNA or RNA detection which is based on the homo-DNA templated Staudinger reduction of the profluorophore rhodamine-azide. The assay is based on a three component system, consisting of a homo-DNA/DNA hybrid probe, a set of homo-DNA reporter strands and the target DNA or RNA. We present two different formats of the assay (Omega probe and linear probe) in which the linear probe was found to perform best with catalytic turnover of the reporter strands (TON: 8) and a match/mismatch discrimination of up to 19. The advantage of this system is that the reporting (homo-DNA) and sensing (DNA) domain are decoupled from each other since the two pairing systems are bioorthogonal. This allows independent optimization of either domain which may lead to higher selectivity in in vivo imaging.

Stoop, Matthias; Desiron, Camille; Leumann, Christian J.

2013-01-01

255

Stereoselective Synthesis Of Homo-Apioneplanocin A As Potential Inhibitor Of S-Adenosylhomocysteine Hydrolase  

Microsoft Academic Search

Homo-apioneplanocin A (1) as a potential inhibitor of S-adenosylhomocysteine hydrolase was synthesized from D-ribose, employing stereoselective hydroxymethylation, regioselective oxidation, and regio- and chemoselective hydroboration as key steps.

Moon Woo Chun; Hyuk Woo Lee; Jin-Hee Kim; Hea Ok Kim; Kang Man Lee; Shantanu Pal; Hyung Ryong Moon; Lak Shin Jeong

2007-01-01

256

Stereoselective synthesis of homo-apioneplanocin A as potential inhibitor of S-adenosylhomocysteine hydrolase.  

PubMed

Homo-apioneplanocin A (1) as a potential inhibitor of S-adenosylhomocysteine hydrolase was synthesized from D-ribose, employing stereoselective hydroxymethylation, regioselective oxidation, and regio- and chemoselective hydroboration as key steps. PMID:18066890

Chun, Moon Woo; Lee, Hyuk Woo; Kim, Jin-Hee; Kim, Hea Ok; Lee, Kang Man; Pal, Shantanu; Moon, Hyung Ryong; Jeong, Lak Shin

2007-01-01

257

Synthesis of Phytochelatins and Homo-Phytochelatins in Pisum sativum 1  

Microsoft Academic Search

In the roots of pea plants (Pisum sativum 1.) cultivated with 20 p~ CdCI, for 3 d, synthesis of phytochelatins (PCs or (yEC),C, where yEC is yglutamylcysteine and C is glycine) and homo- phytochelatins (h-PCs, (yEC),p-alaninel is accompanied by a dras- tic decrease in glutathione (CSH) content, but an increase in homo- glutathione (h-CSH) content. In contrast, the in vitro

Sigrid Klapheck; Sigrid Schlunz; Ludwig Bergmann

258

Sky Luminaries in the Space Orienting Activity of Homo Sapiens in the Middle Palaeolithic  

NASA Astrophysics Data System (ADS)

Data describing the beginnings of the space orienting activity of Homo sapiens is analysed and systematized: observation of the Pole and the recognition of Ursa Major were used as the basis of the determination of the points of the compass. Data and results from astronomy, history of astronomy, archaeology and palaeoanthropology were used for the reconstruction of the evolution of the space orienting activity of Homo sapiens.

Kaurov, E. N.

259

A Galactic Fossil  

NASA Astrophysics Data System (ADS)

How old are the oldest stars? Using ESO's VLT, astronomers recently measured the age of a star located in our Galaxy. The star, a real fossil, is found to be 13.2 billion years old, not very far from the 13.7 billion years age of the Universe. The star, HE 1523-0901, was clearly born at the dawn of time. "Surprisingly, it is very hard to pin down the age of a star", the lead author of the paper reporting the results, Anna Frebel, explains. "This requires measuring very precisely the abundance of the radioactive elements thorium or uranium, a feat only the largest telescopes such as ESO's VLT can achieve." ESO PR Photo 23a/07 ESO PR Photo 23a/07 The 'Cosmic Clock' This technique is analogous to the carbon-14 dating method that has been so successful in archaeology over time spans of up to a few tens of thousands of years. In astronomy, however, this technique must obviously be applied to vastly longer timescales. For the method to work well, the right choice of radioactive isotope is critical. Unlike other, stable elements that formed at the same time, the abundance of a radioactive (unstable) isotope decreases all the time. The faster the decay, the less there will be left of the radioactive isotope after a certain time, so the greater will be the abundance difference when compared to a stable isotope, and the more accurate is the resulting age. Yet, for the clock to remain useful, the radioactive element must not decay too fast - there must still be enough left of it to allow an accurate measurement, even after several billion years. "Actual age measurements are restricted to the very rare objects that display huge amounts of the radioactive elements thorium or uranium," says Norbert Christlieb, co-author of the report. ESO PR Photo 23b/07 ESO PR Photo 23b/07 Uranium Line in the Spectrum of an Old Star Large amounts of these elements have been found in the star HE 1523-0901, an old, relatively bright star that was discovered within the Hamburg/ESO survey [1]. The star was then observed with UVES on the Very Large Telescope (VLT) for a total of 7.5 hours. A high quality spectrum was obtained that could never have been achieved without the combination of the large collecting power Kueyen, one of the individual 8.2-m Unit Telescopes of the VLT, and the extremely good sensitivity of UVES in the ultraviolet spectral region, where the lines from the elements are observed. For the first time, the age dating involved both radioactive elements in combination with the three other neutron-capture elements europium, osmium, and iridium. "Until now, it has not been possible to measure more than a single cosmic clock for a star. Now, however, we have managed to make six measurements in this one star", says Frebel. Ever since the star was born, these "clocks" have ticked away over the eons, unaffected by the turbulent history of the Milky Way. They now read 13.2 billion years. The Universe being 13.7 billion years old, this star clearly formed very early in the life of our own Galaxy, which must also formed very soon after the Big Bang. More Information This research is reported in a paper published in the 10 May issue of the Astrophysical Journal ("Discovery of HE 1523-0901, a Strongly r-Process Enhanced Metal-Poor Star with Detected Uranium", by A. Frebel et al.). The team includes Anna Frebel (McDonald Observatory, Texas) and John E. Norris (The Australian National University), Norbert Christlieb (Uppsala University, Sweden, and Hamburg Observatory, Germany), Christopher Thom (University of Chicago, USA, and Swinburne University of Technlogy, Australia), Timothy C. Beers (Michigan State University, USA), Jaehyon Rhee (Center for Space Astrophysics, Yonsei University, Korea, and Caltech, USA).

2007-05-01

260

Fossils: Observing, Making and Learning  

NSDL National Science Digital Library

In this activity, learners explore how casts of fossilized bones are created and used to learn about dinosaurs. Learners make observations, draw diagrams and share their findings. Learners also make clay molds to create plaster copies of real fossils. Then, learners consider how animals' and dinosaurs' body parts were used for protection, hunting, eating, etc. This activity is featured on pp.11-13 (part of a lesson that begins on p.7) of the "Dinosphere" unit of study for grades 3-5.

Crosslin, Rick; Fortney, Mary; Indianapolis, The C.

2004-01-01

261

Hydrogen versus synthetic fossil fuels  

NASA Astrophysics Data System (ADS)

The fuels most considered for the post petroleum and natural gas era, hydrogen (gaseous and liquid) and synthetic fluid fossil fuels, have been compared by taking into account production costs, utilization efficiencies and environmental effects. Three different cost bases have been used for hydrogen depending on the primary energy sources used in its production. The results show that hydrogen is a much more cost effective energy carrier than synthetic fossil fuels. In addition to its environmental and efficiency benefits, hydrogen causes resource conservation, savings in transportation and capital investment, and reduction in inflation.

Veziroglu, T. N.; Awad, A. H.

262

Tour of Park Geology: Fossils  

NSDL National Science Digital Library

This National Park Service Geology site provides links to tours of individual National Parks, Monuments, and Recreation Areas that contain fossils. Where appropriate, for each park, links are provided to park geology, maps, photographs, geologic research, related links, visitor information, multimedia resources, and teacher features (resources for teaching geology with National Park examples). The list includes places such as the Grand Canyon, Dinosaur National Monument, Yellowstone, and Death Valley, along with less well-known areas such as the John Day Fossil Beds National Monument in Oregon.

263

Geology Fieldnotes: Fossil Butte National Monument, Wyoming  

NSDL National Science Digital Library

Fossil Butte National Monument preserves a 50-million year old bed of Eocene limestone that contains one of the richest fossil deposits in the world. Site features include park geology information, photographs of fossils, related links, visitor information, multimedia resources, and resources for teaching geology with National Park examples. The park geology section discusses the Monument's geologic history and fossil beds, focusing on the conditions that created the fossil-rich region and on the history of fossil collection in the area. A map of the Monument is also included.

264

The Oklo Fossil Fission Reactors  

NSDL National Science Digital Library

This web page gives an overview of the Oklo Fossil Fission Reactors, including the history of the area where the reactor is located, the science behind the nuclear reactions, and reasons for studying this nuclear reactor. This page also includes graphics describing the Physics behind the reactors, maps, and pictures of the reactor.

Loss, Robert

2012-06-15

265

Biomechanics in fossil plant biology  

Microsoft Academic Search

The use of biomechanics for the analysis of the form—function relationship in palaeobotany is reviewed. Four fields of application of biomechanics are discussed and illustrated, i.e. the functional analysis of plants and plant organs (examples: lianas, leaf margin types), reconstruction of fossil plants (growth habit, tree height), functional analysis of ontogeny (lianas, trees), and evolutionary pathways (evolution of early land

Volker Mosbrugger; Anita Roth

1996-01-01

266

Progress of fossil fuel science  

SciTech Connect

Coal is the most abundant and widely distributed fossil fuel. More than 45% of the world's electricity is generated from coal, and it is the major fuel for generating electricity worldwide. The known coal reserves in the world are enough for more than 215 years of consumption, while the known oil reserves are only about 39 times of the world's consumption and the known natural gas reserves are about 63 times of the world's consumption level in 1998. In recent years, there have been effective scientific investigations on Turkish fossil fuels, which are considerable focused on coal resources. Coal is a major fossil fuel source for Turkey. Turkish coal consumption has been stable over the past decade and currently accounts for about 24% of the country's total energy consumption. Lignite coal has had the biggest share in total fossil fuel production, at 43%, in Turkey. Turkish researchers may investigate ten broad pathways of coal species upgrading, such as desulfurization and oxydesulfurization, pyrolysis and hydropyrolysis, liquefaction and hydroliquefaction, extraction and supercritical fluid extraction, gasification, oxidation, briquetting, flotation, and structure identification.

Demirbas, M.F.

2007-07-01

267

Fossil Cetacea of the Caucasus.  

National Technical Information Service (NTIS)

The book by Guram Andreevich Mchedlidze, reviews in detail the fossil cetaceans of the Caucasus. It is based on rich collections from the author's own excavations, supplemented by those preserved in the museums at Tbilisi, etc. A study of the material hel...

G. A. Mchedlidze

1989-01-01

268

Hydrogen versus synthetic fossil fuels  

Microsoft Academic Search

The fuels most considered for the post petroleum and natural gas era, hydrogen (gaseous and liquid) and synthetic fluid fossil fuels, have been compared by taking into account production costs, utilization efficiencies and environmental effects. Three different cost bases have been used for hydrogen depending on the primary energy sources used in its production. The results show that hydrogen is

T. N. Veziroglu; A. H. Awad

1984-01-01

269

Biological fossil CO 2 mitigation  

Microsoft Academic Search

Over ten times more CO2 is fixed by plants into biomass, and annually released by decomposers and food chains, than is emitted to the atmosphere due to the burning of fossil fuels. Human activity is already directly and indirectly affecting almost half of the terrestrial biological C cycle. Management of even a small fraction of the biological C cycle would

Evan Hughes; John R Benemann

1997-01-01

270

Progress of Fossil Fuel Science  

Microsoft Academic Search

Coal is the most abundant and widely distributed fossil fuel. More than 45% of the world's electricity is generated from coal, and it is the major fuel for generating electricity worldwide. The known coal reserves in the world are enough for more than 215 years of consumption, while the known oil reserves are only about 39 times of the world's

M. F. Demirbas

2007-01-01

271

Hagerman Fossil Beds National Monument  

NSDL National Science Digital Library

This National Park Service website offers descriptions of: the animal fossils found at this park, including the extinct Hagerman horse; the geology of the park which is mostly floodplain sediments of primarily silty clays; and the geological, hydrological, and hydrostratigraphical aspects of a landslide model. There are photos of park landslides, prehistoric projectile points, and the historical Oregon Trail.

272

Is schizophrenia the price that Homo sapiens pays for language?  

PubMed

The dichotomy between schizophrenia and manic-depressive illness is, as E. Kraepelin suspected, flawed; no unequivocal separation can be achieved. There are no categories of psychosis, but only continua of variation. However, the definition of nuclear symptoms by K. Schneider reveals the fundamental characteristics of the core syndrome--it is independent of the environment and constant in incidence across populations that have been separated for thousands of years. The associated genetic variation must be as old as Homo sapiens and represent a component of diversity that crosses the population as a whole. The fecundity disadvantage that accompanies the syndrome requires a balance in a substantial and universal advantage; this advantage, it is proposed, is the speciation characteristic of language; language and psychosis have a common evolutionary origin. Language, it is suggested, originated in a critical change on the sex chromosomes (the 'speciation event'--the genetic change that defined the species) occurring in East Africa between 100 and 250 thousand years ago that allowed the two hemispheres to develop with a degree of independence. Language can be understood as bi-hemispheric with one component function--a linear output sequence--confined to the dominant hemisphere--and a second--parallel distributed sampling occurring mainly in the non-dominant hemisphere. This mechanism provides an account of the generativity of language. The significance of nuclear symptoms is that these reflect a breakdown of bi-hemispheric coordination of language, perhaps specifically of the process of 'indexicalisation' (the distinction between 'I' and 'you') of self- versus other-generated references. Nuclear symptoms can be described as 'language at the end of its tether'; the phenomena and population characteristics of the nuclear syndrome of schizophrenia thus yield clues to the origin of the species. PMID:9468348

Crow, T J

1997-12-19

273

Extensii etice ale bipolarismului ideologic: American Way of Life si Homo Sovieticus - Ethical Extensions of Ideological Bipolarism: the American Way of Life and Homo Sovieticus (Romanian version)  

Microsoft Academic Search

During the second part of the 20 th century, bipolarism was not reduced to the formal delimitation of two political-military blocks – the protagonists of the Cold War – but it also entailed the progressive construction of two distinct human types, which animated specific existential paradigms: the American Way of Life and Homo Sovieticus. The American way of life (somewhat

2011-01-01

274

Fossil Energy: Drivers and Challenges.  

NASA Astrophysics Data System (ADS)

Concerns about rapid economic growth, energy security, and global climate change have created a new landscape for fossil energy exploration, production, and utilization. Since 85% of primary energy supply comes from fossil fuels, and 85% of greenhouse gas emissions come from fossil fuel consumption, new and difficult technical and political challenges confront commercial, governmental, and public stakeholders. As such, concerns over climate change are explicitly weighed against security of international and domestic energy supplies, with economic premiums paid for either or both. Efficiency improvements, fuel conservation, and deployment of nuclear and renewable supplies will help both concerns, but are unlikely to offset growth in the coming decades. As such, new technologies and undertakings must both provide high quality fossil energy with minimal environmental impacts. The largest and most difficult of these undertakings is carbon management, wherein CO2 emissions are sequestered indefinitely at substantial incremental cost. Geological formations provide both high confidence and high capacity for CO2 storage, but present scientific and technical challenges. Oil and gas supply can be partially sustained and replaced through exploitation of unconventional fossil fuels such as tar-sands, methane hydrates, coal-to-liquids, and oil shales. These fuels provide enormous reserves that can be exploited at current costs, but generally require substantial energy to process. In most cases, the energy return on investment (EROI) is dropping, and unconventional fuels are generally more carbon intensive than conventional, presenting additional carbon management challenges. Ultimately, a large and sustained science and technology program akin to the Apollo project will be needed to address these concerns. Unfortunately, real funding in energy research has dropped dramatically (75%) in the past three decades, and novel designs in fission and fusion are not likely to provide any substantial offset in the next 30 years when they are most needed internationally.

Friedmann, Julio

2007-04-01

275

Thermal ionization mass spectrometry U-series dating of a hominid site near Nanjing, China  

NASA Astrophysics Data System (ADS)

Mass spectrometric U-series dating of speleothems from Tangshan Cave, combined with ecological and paleoclimatic evidence, indicates that Nanjing Man, a typical Homo erectus morphologically correlated with Peking Man at Zhoukoudian, should be at least 580 k.y. old, or more likely lived during the glacial oxygen isotope stage 16 (˜620 ka). Such an age estimate, which is ˜270 ka older than previous electron spin resonance and alpha-counting U-series dates, has significant implications for the evolution of Asian H. erectus. Dentine and enamel samples from the coexisting fossil layer yield significantly younger apparent ages, that of the enamel sample being only less than one-fourth of the minimum age of Nanjing Man. This suggests that U uptake history is far more complex than existing models can handle. As a result, great care must be taken in the interpretation of electron spin resonance and U-series dates of fossil teeth.

Zhao, Jian-Xin; Hu, Kai; Collerson, Kenneth D.; Xu, Han-Kui

2001-01-01

276

Inferring hominoid and early hominid phylogeny using craniodental characters: the role of fossil taxa.  

PubMed

Recent discoveries of new fossil hominid species have been accompanied by several phylogenetic hypotheses. All of these hypotheses are based on a consideration of hominid craniodental morphology. However, Collard and Wood (2000) suggested that cladograms derived from craniodental data are inconsistent with the prevailing hypothesis of ape phylogeny based on molecular data. The implication of their study is that craniodental characters are unreliable indicators of phylogeny in hominoids and fossil hominids but, notably, their analysis did not include extinct species. We report here on a cladistic analysis designed to test whether the inclusion of fossil taxa affects the ability of morphological characters to recover the molecular ape phylogeny. In the process of doing so, the study tests both Collard and Wood's (2000) hypothesis of character reliability, and the several recently proposed hypotheses of early hominid phylogeny. One hundred and ninety-eight craniodental characters were examined, including 109 traits that traditionally have been of interest in prior studies of hominoid and early hominid phylogeny, and 89 craniometric traits that represent size-corrected linear dimensions measured between standard cranial landmarks. The characters were partitioned into two data sets. One set contained all of the characters, and the other omitted the craniometric characters. Six parsimony analyses were performed; each data set was analyzed three times, once using an ingroup that consisted only of extant hominoids, a second time using an ingroup of extant hominoids and extinct early hominids, and a third time excluding Kenyanthropus platyops. Results suggest that the inclusion of fossil taxa can play a significant role in phylogenetic analysis. Analyses that examined only extant taxa produced most parsimonious cladograms that were inconsistent with the ape molecular tree. In contrast, analyses that included fossil hominids were consistent with that tree. This consistency refutes the basis for the hypothesis that craniodental characters are unreliable for reconstructing phylogenetic relationships. Regarding early hominids, the relationships of Sahelanthropus tchadensis and Ardipithecus ramidus were relatively unstable. However, there is tentative support for the hypotheses that S. tchadensis is the sister taxon of all other hominids. There is support for the hypothesis that A. anamensis is the sister taxon of all hominids except S. tchadensis and Ar. ramidus. There is no compelling support for the hypothesis that Kenyanthropus platyops shares especially close affinities with Homo rudolfensis. Rather, K. platyops is nested within the Homo + Paranthropus + Australopithecus africanus clade. If K. platyops is a valid species, these relationships suggest that Homo and Paranthropus are likely to have diverged from other hominids much earlier than previously supposed. There is no support for the hypothesis that A. garhi is either the sister taxon or direct ancestor of the genus Homo. Phylogenetic relationships indicate that Australopithecus is paraphyletic. Thus, A. anamensis and A. garhi should be allocated to new genera. PMID:15566946

Strait, David S; Grine, Frederick E

2004-12-01

277

ConcepTest: Best Index Fossil  

NSDL National Science Digital Library

Four outcrops of rock are examined in different locations of a state. The rock types and the fossils they contain are illustrated in the adjacent diagram. Which fossil would be the best choice to use as an index ...

278

Energy: Analysing fossil-fuel displacement  

NASA Astrophysics Data System (ADS)

It is commonly assumed that fossil fuels can be replaced by alternative forms of energy. Now research challenges this assumption, and highlights the role of non-technological solutions to reduce fossil-fuel consumption.

Jorgenson, Andrew K.

2012-06-01

279

Identifying Fossils: Exploring the Mississippi River Bluffs  

NSDL National Science Digital Library

This activity is a geology lab where students learn about fossils found in sedimentary rocks and show their understanding by writing a literary nonfiction paper from the perspective of one of those fossils.

280

Hunting Invertebrate Fossils in the Classroom  

NSDL National Science Digital Library

This activity is designed to provide a general knowledge about paleontology and its intimate relationship to sedimentary geology. It will introduce the student to fossils with an emphasis on the invertebrate phyla. As a result of this activity students will acquire a general knowledge of fossils and paleontology, be able to identify the major invertebrate groups commonly found in the fossil record, and learn how fossils tell us about the history of the earth.

Garbisch, Jon

281

The Relationship Between Homosexuality, Internalized Homo-Negativity, and Mental Health in Men Who Have Sex with Men  

Microsoft Academic Search

Whether homosexuality or internalized homo-negativity is the critical variable affecting the mental health of men who have sex with men has long been debated. As part of a larger study, 422 Midwestern homosexual men completed questionnaires examining degree of homosexuality, internalized homo-negativity, and depression. Logistic regression modeling identified internalized homo-negativity, but not degree of homosexuality, as significantly associated with greater

B. R. Simon Rosser; Walter O. Bockting; Michael W. Ross; Michael H. Miner; Eli Coleman

2008-01-01

282

Looking at Fossils in New Ways  

ERIC Educational Resources Information Center

|Existing fossils could be studied from a different prospective with the use of new methods of analysis for gathering more information. The new techniques of studying fossils binds the new and the old techniques and information and provides another way to look at fossils.|

Flannery, Maura C.

2005-01-01

283

Cycads: Fossil evidence of late paleozoic origin  

USGS Publications Warehouse

Plant fossils from Lower Permian strata of the southwestern United States have been interpreted as cycadalean megasporophylls. They are evidently descended from spermopterid elements of the Pennsylvanian Taeniopteris complex; thus the known fossil history of the cycads is extended from the Late Triassic into the late Paleozoic. Possible implications of the Permian fossils toward evolution of the angiosperm carpel are considered.

Mamay, S. H.

1969-01-01

284

A surprise inside a T. Rex fossil  

NSDL National Science Digital Library

When scientists looked inside the leg bone of a recently discovered Tyrannosaurus rex fossil, they found something they weren't expecting. Typically, only the hard parts of an animal, like the bones, are preserved as fossils. This T. rex fossil, however, contained some beautifully preserved soft tissue inside the bone, where the marrow once was.

American Association for the Advancement of Science (AAAS;)

2005-03-24

285

Science 101: What is a fossil?  

NSDL National Science Digital Library

A fossil is a preserved trace of an organism or event. There are many types of fossils.Usually these are preserved in sedimentary rocks--like sandstone, limestone, and shale--laid downon the surface of the planet or under its oceans. A paleontologist provides the basic facts about fossils.

Norell, Mark A.

2003-02-01

286

Identification of Immunoreactive Material in Mammoth Fossils  

Microsoft Academic Search

The fossil record represents a history of life on this planet. Attempts to obtain molecular information from this record by analysis of nucleic acids found within fossils of extreme age have been unsuccessful or called into question. However, previous studies have demonstrated the long-term persistence of peptides within fossils and have used antibodies to extant proteins to demonstrate antigenic material.

Mary Schweitzer; Christopher L. Hill; John M. Asara; Seth H. Pincus

2002-01-01

287

Cretaceous Fossils: Plants Quick Identification Gallery  

NSDL National Science Digital Library

This site forms a component of the CretaceousFossils.com page providing detailed information and high resolution photos of Cretaceous plants. The site supplies a practical, visual resource designed to facilitate identification of plant fossils from the Cretaceous Period. Educators and students alike may find this site and its links useful for viewing, identifying and downloading photos of exceptionally preserved fossil plant specimens.

Keith, Minor; Cretaceousfossils.com

288

Expected Anomalies in the Fossil Record  

Microsoft Academic Search

The problem of intermediates in the fossil record has been frequently discussed ever since Darwin. The extent of `gaps' (missing transitional stages) has been used to argue against gradual evolution from a common ancestor. Traditionally, gaps have often been explained by the improbability of fossilization and the discontinuous selection of found fossils. Here we take an analytical approach and demonstrate

Mareike Fischer; Mike Steel

2007-01-01

289

Fossil groups of galaxies: Are they groups? Are they fossils?  

NASA Astrophysics Data System (ADS)

Fossil groups present a puzzle to current theories of structure formation. Despite the low number of bright galaxies, their high velocity dispersions and high TX indicate cluster-like potential wells. Measured concentration parameters seem very high indicating early formation epochs in contradiction with the observed lack of large and well defined cooling cores. There are very few fossil groups with good quality X-ray data and their idiosyncrasies may enhance these apparent contradictions. The standard explanation for their formation suggests that bright galaxies within half the virial radii of these systems were wiped out by cannibalism forming the central galaxy. Since dry mergers, typically invoked to explain the formation of the central galaxies, are not expected to change the IGM energetics significantly, thus not preventing the formation of cooling cores, we investigate the scenario where recent gaseous (wet) mergers formed the central galaxy injecting energy and changing the chemistry of the IGM in fossil groups. We show a test for this scenario using fossil groups with enough X-ray flux in the Chandra X-ray Observatory archive by looking at individual metal abundance ratio distributions near the core. Secondary SN II powered winds would tend to erase the dominance of SN IA ejecta in the core of these systems and would help to erase previously existing cold cores. Strong SN II-powered galactic winds resulting from galaxy merging would be trapped by their deep potential wells reducing the central enhancement of SN Ia/SN II iron mass fraction ratio. The results indicate that there is a decrement in the ratio of SN Ia to SN II iron mass fraction in the central regions of the systems analyzed, varying from 99±1% in the outer regions to 85±2% within the cooling radius (Figure 1) and would inject enough energy into the IGM preventing central gas cooling. The results are consistent with a scenario of later formation epoch for fossil groups, as they are defined, when compared to galaxy clusters and normal groups.

Dupke, Renato de Alencar; Miller, Eric; de Oliveira, Claudia Mendes; Sodre, Laerte; Rykoff, Eli; de Oliveira, Raimundo Lopes; Proctor, Rob

2010-11-01

290

Face-to-Fossil: An Interview with a Fossil Protoceratops (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

This "interview" with a fossil Protoceratops provides students with an introduction to fossils and paleontology. The information includes what the Protoceratops was like when it was alive, how it became a fossil and how it got to the museum, and what its name means. In addition, there is information about how fossils are treated and displayed at the museum.

291

Evaluating developmental shape changes in Homo antecessor subadult facial morphology.  

PubMed

The fossil ATD6-69 from Atapuerca, Spain, dated to ca. 900 ka (thousands of years ago) has been suggested to mark the earliest appearance of modern human facial features. However, this specimen is a subadult and the interpretation of its morphology remains controversial, because it is unclear how developmental shape changes would affect the features that link ATD6-69 to modern humans. Here we analyze ATD6-69 in an evolutionary and developmental context. Our modern human sample comprises cross-sectional growth series from four populations. The fossil sample covers human specimens from the Pleistocene to the Upper Paleolithic, and includes several subadult Early Pleistocene humans and Neanderthals. We digitized landmarks and semilandmarks on surface and CT scans and analyzed the Procrustes shape coordinates using multivariate statistics. Ontogenetic allometric trajectories and developmental simulations were employed in order to identify growth patterns and to visualize potential adult shapes of ATD6-69. We show that facial differences between modern and archaic humans are not exclusively allometric. We find that while postnatal growth further accentuates the differences in facial features between Neanderthals and modern humans, those features that have been suggested to link ATD6-69's morphology to modern humans would not have been significantly altered in the course of subsequent development. In particular, the infraorbital depression on this specimen would have persisted into adulthood. However, many of the facial features that ATD6-69 shares with modern humans can be considered to be part of a generalized pattern of facial architecture. Our results present a complex picture regarding the polarity of facial features and demonstrate that some modern human-like facial morphology is intermittently present in Middle Pleistocene humans. We suggest that some of the facial features that characterize recent modern humans may have developed multiple times in human evolution. PMID:23998458

Freidline, Sarah E; Gunz, Philipp; Harvati, Katerina; Hublin, Jean-Jacques

2013-08-30

292

FOSSIL SPRINGS ROADLESS AREA, ARIZONA.  

USGS Publications Warehouse

Based on field studies, the Fossil Springs Roadless Area in central Arizona is concluded to have little promise for the occurrence of mineral or energy resources. Rocks in the Supai Formation (Pennsylvanian-Permian) near the central part of the roadless area contain widespread but spotty copper mineralization and trace amounts of uranium. Analyses obtained during the study define geochemical anomalies in two portions of the area that remain unexplained. The suites of anomalous metals suggest the possibility of hydrothermal veins and the presence of ultramafic rocks; neither were found in the field. Although there is little promise for the occurrence of mineral resources in the Fossil Springs Roadless Area, studies to identify the source of the geochemical anomalies could have valuable implications for regional studies and mineral exploration in the surrounding area.

Beard, L. S.; Ellis, C. E.

1984-01-01

293

Oldest fossil basidiomycete clamp connections  

Microsoft Academic Search

A rachis of the fossil filicalean fern Botryopteris antiqua containing abundant septate hyphae with clamp connections is preserved in a late Visean (Mississippian; ~330 Ma) chert from\\u000a Esnost (Autun Basin) in central France. Largely unbranched tubular hyphae pass from cell to cell, but may sometimes produce\\u000a a branch from a clamp connection. Other clamp-bearing hyphae occur clustered in individual cells or

Michael Krings; Nora Dotzler; Jean Galtier; Thomas N. Taylor

2011-01-01

294

Liquid fossil-fuel technology  

NASA Astrophysics Data System (ADS)

Highlights of research activities at Bartlesville Energy Technology Center for the quarter ending March 1982 are summarized. Major research areas are: liquid fossil fuel cycle; extraction (resource assessment and enhanced production); processing (characterization, thermodynamics, processing technology); utilization; and product integration and technology transfer. Special reports include: EOR data base, major new industry tool; properties of crude oils available via telephone hookup; alternative fuels data bank stresses transportation.

1982-07-01

295

Dinosaurs: Ancient Fossils, New Discoveries  

NSDL National Science Digital Library

This Web site, created to complement the Museum's Dinosaurs: Ancient Fossils, New Discoveries exhibit, offers a virtual visit to the Museum, complete with text, photos, video clips, audio interviews, and more and includes much of the information which was in the original exhibit which is now closed. The site includes information on the bio-mechanics of dinosaurs and the reasons behind some of their strange appearances.

296

Plant fossils from White Island  

Microsoft Academic Search

During the D.S.I.R. expedition to White Island in January 1947, plant fossils were discovered in bedded tuffaceous sands on the south side of the island, about 17 chains north-west of Ohauora Point. On this and other coastal headlands a formation of well bedded tuffaceous sands, locally including water-worn pebbles, is exposed from high-tide level to a height of at least

C. A. Fleming

1963-01-01

297

Neanderthals: fossil evidence and DNA.  

PubMed

Neanderthals inhabited Western Eurasia from approximately 300 to 30 thousand years ago (ka). They are distinguished by a unique combination of anatomical traits, and are commonly associated with Middle Paleolithic lithic industries. Current consensus among paleoanthropologists is that they represented a separate Eurasian human lineage, which evolved in isolation from the rest of the Old World and which shared a common ancestor with modern humans in the Middle Pleistocene. It is thought that some aspects of the distinctive Neanderthal anatomy evolved in response to selection related to the extreme cold of the European glacial cycles. Nevertheless, genetic drift seems to be partially responsible for the evolution of these traits. The last appearance of Neanderthals in the fossil record ca. 30 ka BP dates a few millennia after the first appearance of modern humans in Europe. The retrieval of ancient mitochondrial and, more recently, nuclear DNA from Neanderthal fossil puts us in the unique position to combine fossil with genetic evidence to address questions about their evolution, paleobiology and eventual fate. PMID:21957644

Harvati, Katerina

2011-01-01

298

THE NATURE OF FOSSIL GALAXY GROUPS: ARE THEY REALLY FOSSILS?  

SciTech Connect

We use SDSS-DR4 photometric and spectroscopic data out to redshift z {approx} 0.1 combined with ROSAT All Sky Survey X-ray data to produce a sample of 25 fossil groups (FGs), defined as bound systems dominated by a single, luminous elliptical galaxy with extended X-ray emission. We examine possible biases introduced by varying the parameters used to define the sample, and the main pitfalls are also discussed. The spatial density of FGs, estimated via the V/V {sub MAX} test, is 2.83 x 10{sup -6} h {sup 3} {sub 75} Mpc{sup -3} for L{sub X} > 0.89 x 10{sup 42} h {sup -2} {sub 75} erg s{sup -1} consistent with Vikhlinin et al., who examined an X-ray overluminous elliptical galaxy sample (OLEG). We compare the general properties of FGs identified here with a sample of bright field ellipticals generated from the same data set. These two samples show no differences in the distribution of neighboring faint galaxy density excess, distance from the red sequence in the color-magnitude diagram, and structural parameters such as a {sub 4} and internal color gradients. Furthermore, examination of stellar populations shows that our 25 FGs have similar ages, metallicities, and {alpha}-enhancement as the bright field ellipticals, undermining the idea that these systems represent fossils of a physical mechanism that occurred at high redshift. Our study reveals no difference between FGs and field ellipticals, suggesting that FGs might not be a distinct family of true fossils, but rather the final stage of mass assembly in the universe.

La Barbera, F.; Sorrentino, G. [INAF-Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli (Italy); De Carvalho, R. R. [VSTceN, via Moiariello 16, 80131 Napoli (Italy); De la Rosa, I. G. [Instituto de Astrofisica de Canarias, Tenerife (Spain); Gal, R. R. [Institute for Astronomy, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States); Kohl-Moreira, J. L. [Observatorio Nacional, Rua General Jose Cristino 77, Rio de Janeiro (Brazil)

2009-04-15

299

The Nature of Fossil Galaxy Groups: Are They Really Fossils?  

NASA Astrophysics Data System (ADS)

We use SDSS-DR4 photometric and spectroscopic data out to redshift z ~ 0.1 combined with ROSAT All Sky Survey X-ray data to produce a sample of 25 fossil groups (FGs), defined as bound systems dominated by a single, luminous elliptical galaxy with extended X-ray emission. We examine possible biases introduced by varying the parameters used to define the sample, and the main pitfalls are also discussed. The spatial density of FGs, estimated via the V/V MAX test, is 2.83 × 10-6 h 3 75 Mpc-3 for LX > 0.89 × 1042 h -2 75 erg s-1 consistent with Vikhlinin et al., who examined an X-ray overluminous elliptical galaxy sample (OLEG). We compare the general properties of FGs identified here with a sample of bright field ellipticals generated from the same data set. These two samples show no differences in the distribution of neighboring faint galaxy density excess, distance from the red sequence in the color-magnitude diagram, and structural parameters such as a 4 and internal color gradients. Furthermore, examination of stellar populations shows that our 25 FGs have similar ages, metallicities, and ?-enhancement as the bright field ellipticals, undermining the idea that these systems represent fossils of a physical mechanism that occurred at high redshift. Our study reveals no difference between FGs and field ellipticals, suggesting that FGs might not be a distinct family of true fossils, but rather the final stage of mass assembly in the universe.

La Barbera, F.; de Carvalho, R. R.; de la Rosa, I. G.; Sorrentino, G.; Gal, R. R.; Kohl-Moreira, J. L.

2009-04-01

300

Global and local processing in adult humans (Homo sapiens), 5-year-old children (Homo sapiens), and adult cotton-top tamarins (Saguinus oedipus).  

PubMed

This study compared adults (Homo sapiens), young children (Homo sapiens), and adult tamarins (Saguinus oedipus) while they discriminated global and local properties of stimuli. Subjects were trained to discriminate a circle made of circle elements from a square made of square elements and were tested with circles made of squares and squares made of circles. Adult humans showed a global bias in testing that was unaffected by the density of the elements in the stimuli. Children showed a global bias with dense displays but discriminated by both local and global properties with sparse displays. Adult tamarins' biases matched those of the children. The striking similarity between the perceptual processing of adult monkeys and humans diagnosed with autism and the difference between this and normatively developing human perception is discussed. PMID:17115853

Neiworth, Julie J; Gleichman, Amy J; Olinick, Anne S; Lamp, Kristen E

2006-11-01

301

Scaling relations in fossil galaxy groups  

NASA Astrophysics Data System (ADS)

Using Chandra X-ray observations and optical imaging and spectroscopy of a flux-limited sample of five fossil groups, supplemented by additional systems from the literature, we provide the first detailed study of the scaling properties of fossils compared to normal groups and clusters. Fossil groups are dominated by a single giant elliptical galaxy at the centre of an extended bright X-ray halo. In general, all the fossils we study show regular and symmetric X-ray emission, indicating an absence of recent major group mergers. We study the scaling relations involving total gravitational mass, X-ray temperature, X-ray luminosity, group velocity dispersion and the optical luminosity of the fossil groups. We confirm that, for a given optical luminosity of the group, fossils are more X-ray luminous than non-fossil groups. Fossils, however, fall comfortably on the conventional LX-TX relation of galaxy groups and clusters, suggesting that their X-ray luminosity and their gas temperature are both boosted, arguably, as a result of their early formation. This is supported by other scaling relations including the LX-? and TX-? relations in which fossils show higher X-ray luminosity and temperature for a given group velocity dispersion. We find that mass concentration in fossils is higher than in non-fossil groups and clusters. In addition, the MX -TX relation suggests that fossils are hotter, for a given total gravitational mass, both consistent with an early formation epoch for fossils. We show that the mass-to-light ratio in fossils is rather high but not exceptional, compared to galaxy groups and clusters. The entropy of the gas in low-mass fossils appears to be systematically lower than that in normal groups, which may explain why the properties of fossils are more consistent with an extension of cluster properties. We discuss possible reasons for this difference in fossil properties and conclude that the cuspy potential raises the luminosity and temperature of the intergalactic medium (IGM) in fossils. However, this works in conjunction with lower gas entropy, which may arise from less effective pre-heating of the gas.

Khosroshahi, Habib G.; Ponman, Trevor J.; Jones, Laurence R.

2007-05-01

302

Evolution and the Fossil Record  

NSDL National Science Digital Library

This publication of the American Geological Institute is a non-technical introduction to evolution and aims to help the general public gain a better understanding of one of the fundamental underlying concepts of modern science. Concepts covered include geologic time, change through time, Darwin's theory of evolution, evolution as a mechanism for change, the nature of species, the nature of theory, paleontology, and determination of age. Four "case studies" highlight examples of evolution from the fossil record to provide a perspective for understanding the evolution of life on Earth.

Pojeta Jr., John; Springer, Dale

303

The Omo-Turkana Basin fossil hominins and their contribution to our understanding of human evolution in Africa.  

PubMed

The Omo-Turkana Basin, including the hominin fossil sites around Lake Turkana and the sites along the lower reaches of the Omo River, has made and continues to make an important contribution to improving our murky understanding of human evolution. This review highlights the various ways the Omo-Turkana Basin fossil record has contributed to, and continues to challenge, interpretations of human evolution. Despite many diagrams that look suspiciously like comprehensive hypotheses about human evolutionary history, any sensible paleoanthropologist knows that the early hominin fossil record is too meager to do anything other than offer very provisional statements about hominin taxonomy and phylogeny. If history tells us anything, it is that we still have much to learn about the hominin clade. Thus, we summarize the current state of knowledge of the hominin species represented at the Omo-Turkana Basin sites. We then focus on three specific topics for which the fossil evidence is especially relevant: the origin and nature of Paranthropus; the origin and nature of early Homo; and the ongoing debate about whether the pattern of human evolution is more consistent with speciation by cladogenesis, with greater taxonomic diversity or with speciation by anagenetic transformation, resulting in less taxonomic diversity and a more linear interpretation of human evolutionary history. PMID:22170695

Wood, Bernard; Leakey, Meave

304

The influence of homo-buffer layer on structural, optical and electrical properties of ZnO:Al films  

NASA Astrophysics Data System (ADS)

Aluminum-doped ZnO (AZO) films were fabricated on glass by pulsed-laser deposition based on orthogonal design, and influences of homo-buffer layer on structural, optical and electrical properties of AZO films were investigated. The experiment results demonstrate that the homo-buffer layer is very beneficial to improve the quality of AZO films. In addition, both deposition temperature of homo-buffer layer (Thomo-buffer) and deposition oxygen pressure of homo-buffer layer (Phomo-buffer) have a considerable influence on the properties of AZO films. By optimizing the deposition parameters of homo-buffer layer and AZO film synthetically, the AZO film with low resistivity (2.13 × 10-4 ? cm) and high transmittance (89.1%) has been obtained, which is a promising candidate material in transparent electrode applications.

Li, Q. K.; Wang, J. B.; Li, B.; Zhong, X. L.; Wang, F.; Tan, C. B.

2013-10-01

305

Layered Fossil Parfait: Deeper is Older  

NSDL National Science Digital Library

In this activity, learners explore dinosaur fossils by making an edible treat. First, learners read "Dinosaur Bones" by Aliki to examine how fossils are formed. Then, the educator sifts through the class garbage to demonstrate that the deeper something is buried the older it may be. Next, learners make a layered dinosaur fossil model using candy and other treats. This activity is featured on page 30 of the "Dinosphere" unit of study for K-2 learners.

Crosslin, Rick; Fortney, Mary; Indianapolis, The C.

2004-01-01

306

A Synthesized Approach to the Study of the Evolution of Speech in Homo sapiens  

Microsoft Academic Search

This essay explores the evolution of speech in humans by synthesizing the approaches taken from many different disciplines. It begins with a survey of the neural and anatomical structures responsible for speech Homo sapiens. This is followed by comparative studies of the vocal communication and linguistic behavior of a number of nonhuman species, including birds and other primates. The essay

Nicholas Holowka

2007-01-01

307

FAUSTIAN FIGURES: MODERNITY AND MALE (HOMO)SEXUALITIES IN SPANISH COMMERCIAL LITERATURE, 1900-1936  

Microsoft Academic Search

I contend in this study that commercial novels and theater from early twentiethcentury Spain often present male (homo)sexual characters as a point of constellation for anxieties regarding modernization in Madrid and Barcelona. In works by Jacinto Benavente, Josep Maria de Sagarra, El Caballero Audaz (José María Carretero), Antonio de Hoyos y Vinent, Carmen de Burgos, Álvaro Retana, Eduardo Zamacois, and

Jeffrey Zamostny

2012-01-01

308

Actions of picrotoxinin analogues on an expressed, homo-oligorneric GABA receptor receptor of Drosophila melanogaster  

Microsoft Academic Search

The actions of picrotoxinin and four of its analogues were tested on a Drosophila melanogaster homo-oligomeric GABA (?-aminobutyric acid) receptor formed when RDL (resistance to dieldrin) subunits were expressed in Xenopus oocytes. In agreement with previously reported studies on native insect GABA receptors and native and expressed vertebrate GABA receptors, acetylation of the bridgehead hydroxyl group (picrotoxinin acetate) greatly reduced

Y. Shirai; A. M. Hosie; S. D. Buckingham; C. W. Holyoke; H. A. Baylis; D. B. Sattelle

1995-01-01

309

Spatial Construction Skills of Chimpanzees ("Pan Troglodytes") and Young Human Children ("Homo Sapiens Sapiens")  

ERIC Educational Resources Information Center

|Spatial construction tasks are basic tests of visual-spatial processing. Two studies have assessed spatial construction skills in chimpanzees (Pan troglodytes) and young children (Homo sapiens sapiens) with a block modelling task. Study 1a subjects were three young chimpanzees and five adult chimpanzees. Study 1b subjects were 30 human children…

Poti, Patrizia; Hayashi, Misato; Matsuzawa, Tetsuro

2009-01-01

310

Greater Emphasis on Female Attractiveness in Homo sapiens: A Revised Solution to an Old Evolutionary Riddle  

Microsoft Academic Search

Substantial evidence from psychology and cross-cultural anthropology supports a general rule of greater emphasis on female physical attractiveness in Homo sapiens. As sensed by Darwin (1871) and clarified by Trivers (1972), generally higher female parental investment is a key determinant of a common pattern of sexual selection in which male animals are more competitive, more eager sexually and more conspicuous

Jonathan Gottschall

311

Ethical Extensions of Ideological Bipolarism: the American Way of Life and Homo Sovieticus  

Microsoft Academic Search

During the second part of the 20th century, bipolarism was not reduced to the formal delimitation of two political-military blocks – the protagonists of the Cold War – but it also entailed the progressive construction of two distinct human types, which animated specific existential paradigms: the American Way of Life and Homo Sovieticus. The American way of life (somewhat extended

2011-01-01

312

Female Condition Influences Preferences for Sexual Dimorphism in Faces of Male Humans (Homo sapiens )  

Microsoft Academic Search

In some species, female condition correlates positively with preferences for male secondary sexual traits. Women's preferences for sexually dimorphic characteristics in male faces (facial masculinity) have recently been reported to covary with self-reported attractiveness. As women's attractiveness has been proposed to signal reproductive condition, the findings in human (Homo sapiens) and other species may reflect similar processes. The current study

I. S. Penton-Voak; A. C. Little; B. C. Jones; D. M. Burt; B. P. Tiddeman; D. I. Perrett

2003-01-01

313

Cold Spring Harbor symposia on quantitative biology: Volume 51, Molecular biology of /ital Homo sapiens/  

SciTech Connect

This volume is the second part of a collection of papers submitted by the participants to the 1986 Cold Spring Harbor Symposium on Quantitative Biology entitled Molecular Biology of /ital Homo sapiens/. The 49 papers included in this volume are grouped by subject into receptors, human cancer genes, and gene therapy. (DT)

Not Available

1986-01-01

314

Seeking Homo Economicus: The Canadian State and the Strange Story of the Business Immigration Program  

Microsoft Academic Search

Through a policy study, this article examines the active but compromised authority of the state as it engages the global “space of flows.” Business immigration programs in close to thirty countries announce the state's intent to domesticate the unruly forces of globalization by enticing its principal agent, homo economicus. With the objective of priming economic development using immigrant capital and

David Ley

2003-01-01

315

Human (Homo sapiens) Facial Attractiveness and Sexual Selection: The Role of Symmetry and Averageness  

Microsoft Academic Search

We hypothesized from the parasite theory of sexual selection that men (Homo sapiens) would prefer averageness and symmetry in women's faces, that women would prefer averageness and symmetry in men's faces, and that women would prefer largeness (not averageness) of the secondary sexual traits of men's faces. We generated computer images of men's and women's faces and of composites of

Karl Grammer; Randy Thornhill

1994-01-01

316

Prelude to a Theory of Homo Absurdus: Variations on Themes from Thorstein Veblen and Jean Baudrillard  

Microsoft Academic Search

Homo absurdus refers to an economic character who differs markedly from the leading characters in both orthodox and Marxist interpretations of economic life. The social and psychological characteristics of absurdus are drawn from Thorstein Veblen's ironical and existential insights into business culture. In particular, the article shows how Veblen uses irony to describe and explore the type of despair that

Alan W Dyer

1997-01-01

317

Teaching Through Trade Books: Fascinating Fossil Finds  

NSDL National Science Digital Library

This month's Teaching Through Trade Books column engages students in "unearthing" fossils and exploring the processes scientists use in uncovering these fascinating finds and interpreting Earth's past.

Royce, Chrstine A.

2004-10-01

318

Fossil fuel biodegradation: Laboratory studies  

SciTech Connect

Biodegradation of the polycyclic: aromatic hydrocarbons of creosote by undefined bacterial cultures was shown to be accompanied by the accumulation of neutral and acidic oxidation products. Formation of a number of identified neutral products is accounted for by demonstration of anomalous actions of an arene dioxygenase on the benzylic methylene and methylene carbons of napthencaromatic hydrocarbons. Both neutral and acidic water-soluble fractions are also formed when various mixed bacterial cultures degrade weathered crude oil. While constituents of these fractions are not yet identified, the neutral materials have been shown to be toxic to developing embryos of invertebrates. These observations are discussed in relation to chemical and toxicological assessments of biodegradation of the complex chemical mixtures of fossil fuels. 14 refs., 3 figs., 1 tab.

Chapman, P.J. [Environmental Research Lab., Gulf Breeze, FL (United States); Shelton, M.; Selifonov, S. [Univ. of West Florida, Pensacola, FL (United States); Grifoll, M. [Univ. of Barcelona (Spain)

1995-06-01

319

Fossil fuel biodegradation: laboratory studies.  

PubMed Central

Biodegradation of the polycyclic aromatic hydrocarbons of creosote by undefined bacterial cultures was shown to be accompanied by the accumulation of neutral and acidic oxidation products. Formation of a number of identified neutral products is accounted for by demonstration of anomalous actions of an arene dioxygenase on the benzylic methylene and methylene carbons of napthenoaromatic hydrocarbons. Both neutral and acidic water-soluble fractions are also formed when various mixed bacterial cultures degrade weathered crude oil. While constituents of these fractions are not yet identified, the neutral materials have been shown to be toxic to developing embryos of invertebrates. These observations are discussed in relation to chemical and toxicological assessments of biodegradation of the complex chemical mixtures of fossil fuels.

Chapman, P J; Shelton, M; Grifoll, M; Selifonov, S

1995-01-01

320

Proposing Explanations for Fossil Footprints  

NSDL National Science Digital Library

This activity will allow students to observe and interpret fossil footprint evidence. From the evidence, they are asked to construct defensible hypotheses or explanations for events that took place in the geological past. Students will be asked to propose explanations and make predictions based on evidence, recognize and analyze alternative explanations and predictions, understand that scientific explanations are subject to change as new evidence becomes available, and understand that scientific explanations must meet certain criteria. Students learn that scientific explanations must be consistent with experimental and observational evidence, should also be logical, respect the rules of evidence, be open to criticism, report methods and procedures, and make knowledge public. The site contains all of the information and instructions needed to complete the activity.

321

Fossil diatoms and neogene paleolimnology  

USGS Publications Warehouse

Diatoms have played an important role in the development of Neogene continental biostratigraphy and paleolimnology since the mid-19th Century. The history of progress in Quaternary diatom biostratigraphy has developed as a result of improved coring techniques that enable sampling sediments beneath existing lakes coupled with improved chronological control (including radiometric dating and varve enumeration), improved statistical treatment of fossil diatom assemblages (from qualitative description to influx calculations of diatom numbers or volumes), and improved ecological information about analogous living diatom associations. The last factor, diatom ecology, is the most critical in many ways, but progresses slowly. Fortunately, statistical comparison of modern diatom assemblages and insightful studies of the nutrient requirements of some common freshwater species are enabling diatom paleolimnologists to make more detailed interpretations of the Quaternary record than had been possible earlier, and progress in the field of diatom biology and ecology will continue to refine paleolimnological studies. The greater age and geologic setting of Tertiary diatomaceous deposits has prompted their study in the contexts of geologic history, biochronology and evolution. The distribution of diatoms of marine affinities in continental deposits has given geologists insights about tectonism and sea-level change, and the distribution of distinctive (extinct?) diatoms has found utilization both in making stratigraphic correlations between outcrops of diatomaceous deposits and in various types of biochronological studies that involve dating deposits in different areas. A continental diatom biochronologic scheme will rely upon evolution, such as the appearance of new genera within a family, in combination with regional environmental changes that are responsible for the wide distribution of distinctive diatom species. The increased use of the scanning electron microscope for the detailed descriptions of fossil diatoms will provide the basis for making more accurate correlations and identifications, and the micromorphological detail for speculations about evolutionary relationships. ?? 1988.

Platt, Bradbury, J.

1988-01-01

322

Some Quantitative Dental Characters of Fossil Anthropoids  

Microsoft Academic Search

Comparisons have been made by means of appropriate statistical methods between the dental dimensions and indices of several species of fossil anthropoids and those of modern apes. In nearly all cases the fossil teeth have been found not to differ significantly from one or other type of extant great ape, and in several a strong resemblance exists between all the

E. H. Ashton; S. Zuckerman

1950-01-01

323

Silica-replaced fossils through the Phanerozoic  

Microsoft Academic Search

A systematic survey of 1863 papers on macrobenthic assemblages reveals that an average of 21% of published Paleozoic papers concern silicified fossils, but that average drops to just 4% for post-Paleozoic papers. During the Paleozoic, silicified fossil occurrences do not significantly correlate with the amount of shelf chert, outcrop area, time, duration of geologic intervals, or carbonate rock volume. This

Jennifer K. Schubert; David L. Kidder; Douglas H. Erwin

1997-01-01

324

Forty Years Later: Updating the Fossilization Hypothesis  

ERIC Educational Resources Information Center

A founding concept in second language acquisition (SLA) research, fossilization has been fundamental to understanding second language (L2) development. The Fossilization Hypothesis, introduced in Selinker's seminal text (1972), has thus been one of the most influential theories, guiding a significant bulk of SLA research for four decades; 2012…

Han, ZhaoHong

2013-01-01

325

Accuracy of Fossils and Dating Methods  

NSDL National Science Digital Library

The issue-focused, peer-reviewed article asserts that fossil dating is accurate because the method follows strict scientific guidelines: the age of rocks around a fossil can be considered, mathematical calculations are used, the state of decay, carbon-14, and isotopes figure in calculations, and tree of life relationships often help sort the dates.

Michael Benton (University of Bristol, UK;)

2001-01-01

326

Safe venting for fossil fuel fired equipment  

Microsoft Academic Search

Energy conservation in the residential heating market is one of the used methods to reduce the use of fossil fuels and extend the life of the known North American fossil fuel reserves. The other benefit, is the reduction of combustion by-products that are produced and then injected into the atmosphere. The drive for energy conservation has not been without its

H. R. West; K. D. Bryant

1988-01-01

327

Fossil energy program report, 1975--1976  

Microsoft Academic Search

The newly created Energy Research and Development Administration greatly expanded its horizons for Fossil Energy technology in 1975-76, especially in moving toward large demonstration projects for converting coal to clean fuels. Significant progress was achieved in developing the Fossil Energy research program, notably the enlistment of universities, and in securing industry participation in cost-sharing projects for the enhanced recovery of

R. C. Jr. Seamans; P. C. White

1976-01-01

328

Fossil fuel usage and the environment  

Microsoft Academic Search

The Greenhouse Effect and global warming, ozone formation in the troposphere, ozone destruction in the stratosphere, and acid rain are important environmental issues. The relationship of fossil fuel usage to some of these issues is discussed. Data on fossil fuel consumption and the sources and sinks of carbon dioxide, carbon monoxide, methane, nitrogen and sulfur oxides, and ozone indicate that

Klass

1990-01-01

329

When will fossil fuel reserves be diminished?  

Microsoft Academic Search

Crude oil, coal and gas are the main resources for world energy supply. The size of fossil fuel reserves and the dilemma that “when non-renewable energy will be diminished” is a fundamental and doubtful question that needs to be answered. This paper presents a new formula for calculating when fossil fuel reserves are likely to be depleted and develops an

Shahriar Shafiee; Erkan Topal

2009-01-01

330

Do alternative energy sources displace fossil fuels?  

NASA Astrophysics Data System (ADS)

A fundamental, generally implicit, assumption of the Intergovernmental Panel on Climate Change reports and many energy analysts is that each unit of energy supplied by non-fossil-fuel sources takes the place of a unit of energy supplied by fossil-fuel sources. However, owing to the complexity of economic systems and human behaviour, it is often the case that changes aimed at reducing one type of resource consumption, either through improvements in efficiency of use or by developing substitutes, do not lead to the intended outcome when net effects are considered. Here, I show that the average pattern across most nations of the world over the past fifty years is one where each unit of total national energy use from non-fossil-fuel sources displaced less than one-quarter of a unit of fossil-fuel energy use and, focusing specifically on electricity, each unit of electricity generated by non-fossil-fuel sources displaced less than one-tenth of a unit of fossil-fuel-generated electricity. These results challenge conventional thinking in that they indicate that suppressing the use of fossil fuel will require changes other than simply technical ones such as expanding non-fossil-fuel energy production.

York, Richard

2012-06-01

331

Global Warming and Future Fossil Fuel Consumption  

Microsoft Academic Search

This paper reviews the potential for reducing emissions of CO, by reducing the use of fossil fuels. Following a brief review of current data on greenhouse gas emissions and global warming\\/ the author considers three ways of decreasing fossil fuel consumption: doing without; maximizing conversion efficiencies; and reducing the use of energy intensive products through better design and extensive recycling

Vaclav Smil

1989-01-01

332

The Microbial Origin of Fossil Fuels  

Microsoft Academic Search

The authors have investigated the genesis of fossil fuels and different kinds of sedimentary deposits by studying the structure of individual fossil compounds in order to deduce the structure of their precursors in living organisms. Analysis revealed unexpected similarities, specifically in the pattern of peaks in gas chromatograms in the Cââ to Cââ region. Thousands of samples taken from all

Guy Ourisson; Pierre Albrecht; Michel Rohmer

1984-01-01

333

Forty Years Later: Updating the Fossilization Hypothesis  

ERIC Educational Resources Information Center

|A founding concept in second language acquisition (SLA) research, fossilization has been fundamental to understanding second language (L2) development. The Fossilization Hypothesis, introduced in Selinker's seminal text (1972), has thus been one of the most influential theories, guiding a significant bulk of SLA research for four decades; 2012…

Han, ZhaoHong

2013-01-01

334

John Day Fossil Beds National Monument  

NSDL National Science Digital Library

This National Park Service website offers an education section which includes: programs for visiting school groups involving the geological and evolutionary processes of the park, working with fossil casts, and other fossil activities; a list of classroom materials to send for (some have cost) including a horse fossil study kit, a general fossil kit, a teacher packet, and a videotape on the paleontology work at the park and evolution of the horse; and a list of teacher workshops in Oregon. There are species lists for vertebrate and plant fossils, diagrams of the major geologic formations and illustrations of different paleobiomes, species lists for existing flora and fauna, and a fire management plan. Regional and park history is covered as well as the history of the Chinookan, Sahaptian, Shoshonean, and Salishan Indians of Eastern Oregon. There is also information for planning a visit to the park.

335

Physiological and life history strategies of a fossil large mammal in a resource-limited environment  

PubMed Central

Because of their physiological and life history characteristics, mammals exploit adaptive zones unavailable to ectothermic reptiles. Yet, they perform best in energy-rich environments because their high and constant growth rates and their sustained levels of resting metabolism require continuous resource supply. In resource-limited ecosystems such as islands, therefore, reptiles frequently displace mammals because their slow and flexible growth rates and low metabolic rates permit them to operate effectively with low energy flow. An apparent contradiction of this general principle is the long-term persistence of certain fossil large mammals on energy-poor Mediterranean islands. The purpose of the present study is to uncover the developmental and physiological strategies that allowed fossil large mammals to cope with the low levels of resource supply that characterize insular ecosystems. Long-bone histology of Myotragus, a Plio-Pleistocene bovid from the Balearic Islands, reveals lamellar-zonal tissue throughout the cortex, a trait exclusive to ectothermic reptiles. The bone microstructure indicates that Myotragus grew unlike any other mammal but similar to crocodiles at slow and flexible rates, ceased growth periodically, and attained somatic maturity extremely late by ?12 years. This developmental pattern denotes that Myotragus, much like extant reptiles, synchronized its metabolic requirements with fluctuating resource levels. Our results suggest that developmental and physiological plasticity was crucial to the survival of this and, perhaps, other large mammals on resource-limited Mediterranean Islands, yet it eventually led to their extinction through a major predator, Homo sapiens.

Kohler, Meike; Moya-Sola, Salvador

2009-01-01

336

Virtual assessment of the endocranial morphology of the early modern European fossil calvaria from cioclovina, romania.  

PubMed

Endocasts provide evidence on size and shape characteristics, blood supply trajectories, and neurological features of the brain, allowing comparative analyses of fossil hominins crucial to our understanding of human brain evolution. Here, we assess the morphological features of the virtual endocast of the Cioclovina Upper Paleolithic calvarium, one of the earliest reliably dated European modern human fossils. Our study was conducted on a computed tomography (CT) scan of the original specimen. The endocranial profile was approximated via a semiautomatic segmentation of the CT data. Virtual reconstructions of the endocast were used for assessing the morphological features of the endocranium and for the estimation of the endocranial volume. Cioclovina exhibits a clockwise torque with a small anterior extension of the left frontal lobe over the right one and a protrusion of the right occipital lobe over the left, most likely due to the superior sagittal sinus coursing over the occipital pole. There is an obvious right predominance of the posterior drainage system. Interestingly, the area of the frontal sinus is occupied by dense bony tissue with small air cells corresponding probably to a natural bony loss in the diploë and to vascular spaces. An estimated endocranial volume of 1498.53 cc was calculated. The convolutional details of the third inferior frontal gyrus (Broca's caps) are indistinguishable from those found in modern Homo sapiens, and the left occipital lobe appears wider than the right, a possible correlate of right-handedness. Our metric analysis of endocranial measurements also aligns Cioclovina with modern humans. PMID:21634023

Kranioti, Elena F; Holloway, Ralph; Senck, Sascha; Ciprut, Tudor; Grigorescu, Dan; Harvati, Katerina

2011-06-01

337

ANALISIS SIFAT FOTOSENSITIVITAS SENYAWA ANTIBAKTERI TURUNAN FLUOROKUINOLON BERDASARKAN DATA TRANSISI ELEKTRONIK DAN SELISIH ENERGI ORBITAL HOMO-LUMO PHOTOSENSITIVITY ANALYSIS OF FLUOROQUINOLONE ANTIBACTERIAL COMPOUNDS BASED ON ELECTRONIC TRANSITIONS DATA AND HOMO-LUMO ENERGY BAND GAP  

Microsoft Academic Search

INTISARI Telah dilakukan analisis sifat fotosensitivitas dari senyawa antibakteri fluorokuinolon berdasarkan karakteristik spektra elektronik dan selisih energi HOMO-LUMO. Perhitungan spektra elektronik dilakukan menggunakan metode semiempirik ZINDO\\/s untuk mengetahui sifat fotosensitivitasnya pada daerah ultraviolet (?=200-400 nm) untuk molekul pada fasa gas dalam bentuk ion zwitter-nya. Perhitungan selisih energi HOMO-LUMO dilakukan untuk memprediksikan kekuatan fotosensitivitas dari senyawa antibakteri tersebut. Kedua proses perhitungan

Iqmal Tahir; Faiz El Makky; Harno Dwi Pranowo; Karna Wijaya

338

HOMO band dispersion of crystalline rubrene: Effects of self-energy corrections within the GW approximation  

NASA Astrophysics Data System (ADS)

We investigate the band dispersion and relevant electronic properties of rubrene single crystals within the GW approximation. Due to the self-energy correction, the dispersion of the highest occupied molecular orbital (HOMO) band increases by 0.10 eV compared to the dispersion of the Kohn-Sham eigenvalues within the generalized gradient approximation, and the effective hole mass consequently decreases. The resulting value of 0.90 times the electron rest mass along the ?-Y direction in the Brillouin zone is closer to experimental measurements than that obtained from density-functional theory. The enhanced bandwidth is explained in terms of the intermolecular hybridization of the HOMO(Y) wave function along the stacking direction of the molecules. Overall, our results support the bandlike interpretation of charge-carrier transport in rubrene.

Yanagisawa, Susumu; Morikawa, Yoshitada; Schindlmayr, Arno

2013-09-01

339

Synthesis and antiproliferative activity of C-homo-lactam derivatives of 7-deoxycholic acid.  

PubMed

Using deoxycholic acid as starting materials, a series of 12a-aza-C-homo-12-one 7-deoxycholic acid derivatives were synthesized The antiproliferative activity of the synthesized compounds against some carcinoma cell lines was investigated. The results showed that some 12-oxy-12a-aza-C-homo-7-deoxycholic acid derivatives displayed distinct cytotoxicity to HeLa (human cervical carcinoma) and Tu 686 (laryngocarcinoma) tumor cell lines. In particular, the IC50 values of the compounds 6 and 7 against Tu 686 cells are 16.7 and 19.8 ?M/L respectively. The information obtained from the studies may be useful for the design of novel chemotherapeutic drugs. PMID:23466224

Huang, Yanmin; Cui, Jianguo; Chen, Sijing; Gan, Chunfang; Yao, Qiucui; Lin, Qifu

2012-08-24

340

Gold-caged metal clusters with large HOMO-LUMO gap and high electron affinity.  

PubMed

We report a series of isoelectronic gold-caged metal clusters, M@Au14 (M = Zr, Hf), and anion clusters, M@Au14- (M = Sc, Y), all having a calculated HOMO-LUMO gap larger than the well-known tetrahedral cluster Au20-the 3D metal cluster with a very large measured HOMO-LUMO gap (1.77 eV). The clusters M@Au14 (M = Sc, Y) also exhibit a calculated electron affinity (EA) and vertical detachment energy (VDE) not only higher than the "superhalogen" icosahedral Al13 cluster but also possibly even higher than a Cl atom which has the highest (measured) elemental EA or VDE (3.61 eV). PMID:16277491

Gao, Yi; Bulusu, Satya; Zeng, Xiao Cheng

2005-11-16

341

Fossil oak galls preserve ancient multitrophic interactions  

PubMed Central

Trace fossils of insect feeding have contributed substantially to our understanding of the evolution of insect–plant interactions. The most complex phenotypes of herbivory are galls, whose diagnostic morphologies often allow the identification of the gall inducer. Although fossil insect-induced galls over 300?Myr old are known, most are two-dimensional impressions lacking adequate morphological detail either for the precise identification of the causer or for detection of the communities of specialist parasitoids and inquilines inhabiting modern plant galls. Here, we describe the first evidence for such multitrophic associations in Pleistocene fossil galls from the Eemian interglacial (130?000–115?000 years ago) of The Netherlands. The exceptionally well-preserved fossils can be attributed to extant species of Andricus gallwasps (Hymenoptera: Cynipidae) galling oaks (Quercus), and provide the first fossil evidence of gall attack by herbivorous inquiline gallwasps. Furthermore, phylogenetic placement of one fossil in a lineage showing obligate host plant alternation implies the presence of a second oak species, Quercus cerris, currently unknown from Eemian fossils in northwestern Europe. This contrasts with the southern European native range of Q. cerris in the current interglacial and suggests that gallwasp invasions following human planting of Q. cerris in northern Europe may represent a return to preglacial distribution limits.

Stone, Graham N; van der Ham, Raymond W.J.M; Brewer, Jan G

2008-01-01

342

Summary statistics for fossil spider species taxonomy.  

PubMed

Spiders (Araneae) are one of the most species-rich orders on Earth today, and also have one of the longest geological records of any terrestrial animal groups, as demonstrated by their extensive fossil record. There are currently around 1150 described fossil spider species, representing 2.6% of all described spiders (i.e. extinct and extant). Data for numbers of fossil and living spider taxa described annually (and various other metrics for the fossil taxa) were compiled from current taxonomic catalogues. Data for extant taxa showed a steady linear increase of approximately 500 new species per year over the last decade, reflecting a rather constant research activity in this area by a large number of scientists, which can be expected to continue. The results for fossil species were very different, with peaks of new species descriptions followed by long troughs, indicating minimal new published research activity for most years. This pattern is indicative of short bursts of research by a limited number of authors. Given the frequent discovery of new fossil deposits containing spiders, a wealth of new material coming to light from previously worked deposits, and the application of new imaging techniques in palaeoarachnology that allow us to extract additional data from historical specimens, e.g. X-ray computed tomography, it is important not only to ensure a sustained research activity on fossil spiders (and other arachnids) through training and enthusing the next generation of palaeoarachnologists, but preferably to promote increased research and expertise in this field. PMID:22639535

Penney, David; Dunlop, Jason A; Marusik, Yuri M

2012-05-08

343

Cycling operation of fossil plants  

SciTech Connect

This report presents a methodology for examining the economic feasibility of converting fossil power plants from baseload to cycling service. It employs this approach to examine a proposed change of Pepco's Potomac River units 3, 4, and 5 from baseload operation of two-shift cycling. The project team first reviewed all components and listed potential cycling effects involved in the conversion of Potomac River units 3, 4, and 5. They developed general cycling plant screening criteria including the number of hot, warm, or cold restart per year and desired load ramp rates. In addition, they evaluated specific limitations on the boiler, turbine, and the balance of plant. They estimated the remaining life of the facility through component evaluation and boiler testing and also identified and prioritized potential component deficiencies by their impact on key operational factors: safety, heat rate, turn down, startup/shutdown time, and plant availability. They developed solutions to these problems; and, since many solutions mitigate more than one problem, they combined and reprioritized these synergistic solutions. Economic assessments were performed on all solutions. 13 figs., 20 tabs.

Bhatnagar, U.S.; Weiss, M.D.; White, W.H. (Potomac Electric Power Co., Washington, DC (USA)); Buchanan, T.L.; Harvey, L.E.; Shewchuk, P.K.; Weinstein, R.E. (Gilbert/Commonwealth, Inc., Reading, PA (USA))

1991-05-01

344

Systematics of some enigmatic "fossils"  

NSDL National Science Digital Library

Students are given sets of different shaped fasteners (staples, paper clips, tacks, etc.) and work with the instructor through a guided exercise in which they construct a character matrix and cladogram depicting the phylogeny of the "organisms". Students are then divided into small groups; each group receives a set of various shapes/colors of pasta. (The sets are all the same.) Each group must decide how many species are present in their sample (considering the potential for ontogenetic and sexual variation within species), choose and define characters for a cladistic analysis, and construct a character matrix. The instructor runs the matrices through cladistic analysis software, and the following week the students receive the results from analysis of each group's data. The class then discusses the effects of species definition, character choice, etc. on phylogenetic hypotheses. The activity allows students to directly confront issues of identifying and distinguishing morphological species. Conflicting results obtained by different groups analyzing the same data set drive home the complicated nature of character choice and definition in construction of a character matrix for cladistic analysis, and underscore the fact that individual cladograms represent phylogenetic hypotheses subject to modification by further analysis. (This last point becomes necessary background as students encounter different/competing hypotheses of phylogenetic relationships during study of fossil invertebrates.)

Tumarkin-Deratzian, Allison

345

Homo sapiens (Cro-magnon and modern human), Chris StringerSite: DNA Interactive (www.dnai.org)  

NSDL National Science Digital Library

Interviewee: Chris Stringer DNAi Location:Applications>Human origins>our family tree>Modern humans: a late arrival Human origins expert Chris Stringer talks about the arrival of Homo sapiens and our possible ancestors.

2008-10-06

346

Molecular Biology of Homo Sapiens: Abstracts of Papers Presented at the 51ST Cold Spring Harbor Symposium on Quantitative Biology.  

National Technical Information Service (NTIS)

This volume contains abstracts of papers presented at the 51st Cold Springs Harbor Symposium on Quantitative Biology. The topic for this meeting was the ''Molecular Biology of Homo sapiens.'' Sessions were entitled Human Gene Map, Human Cancer Genes, Gene...

J. D. Watson M. Siniscalco

1986-01-01

347

The Dutch Homo-Emancipation Policy and its Silencing Effects on Queer Muslims  

Microsoft Academic Search

The recent Dutch homo-emancipation policy has identified religious communities, particularly within migrant populations, as\\u000a a core target group in which to make homosexuality more ‘speakable’. In this article we examine the paradoxical silencing\\u000a tendencies of this ‘speaking out’ policy on queer Muslim organisations in the Netherlands. We undertake this analysis as the\\u000a Dutch government is perhaps unique in developing an

Suhraiya JivrajAnisa de Jong; Anisa de Jong

2011-01-01

348

Self-Control Across Species (Columba livia, Homo sapiens, and Rattus norvegicus )  

Microsoft Academic Search

Data from six previous studies of self-control behavior were compared against predictions made by the matching law and by molar maximization. The studies involved pigeons (Columba livia), rats (Rattus norvegicus), and 3-year-old, 5-year-old, and adult humans (Homo sapiens) who had received food as the reinforcer, and adult humans who had received points exchangeable for money as the reinforcer. Neither theory

Henry Tobin; A. W. Logue

1994-01-01

349

Abiotrophic gene action in Homo sapiens : Potential mechanisms and significance for the pathobiology of aging  

Microsoft Academic Search

A subset of genetic loci ofHomo sapiens are reviewed that: 1) have the potential for allelic variation (either mutation or polymorphism) such that degenerative and\\/or proliferative phenotypic aberrations may be of relatively late onset (‘abiotrophic’); 2) have phenotypic features which overlap, to some extent, with those of important age-related disorders of man (many of which are systematically tabulated in this

George M. Martin

1993-01-01

350

Syncollin Homo-Oligomers Associate with Lipid Bilayers in the Form of Doughnut-shaped Structures  

Microsoft Academic Search

Syncollin is a 16-kDa protein that is associated with the luminal surface of the zymogen granule membrane in the pancreatic acinar cell. Detergent-solubilized, purified syncollin migrates on sucrose density gradients as a large (120-kDa) protein, suggesting that it exists naturally as a homo-oligomer. In this study, we investigated the structure of the syncollin oligomer. Chemical cross-linking of syncollin produced a

N. A. Geisse; B. Wäsle; D. E. Saslowsky; R. M. Henderson; J. M. Edwardson

2002-01-01

351

Passion's re-territorializations: mapping the mixed semiotics of unsafe homo passional assemblages  

Microsoft Academic Search

This paper conducts a mixed semiotics of unsafe homo passional assemblages. It begins with an exposition of Deleuze and Guattari's instructions for mapping the multidimensional circuitry of assemblages along the generative and transformative poles. Unsafe sex is a line of desiring movement involving expressive matter from the pick-up machine. After HIV\\/AIDS, the pick-up machine's de-territorialised movements have been problematised, their

Craig Osmond

2010-01-01

352

Post-cranial skeletons of hypothyroid cretins show a similar anatomical mosaic as Homo floresiensis.  

PubMed

Human remains, some as recent as 15 thousand years, from Liang Bua (LB) on the Indonesian island of Flores have been attributed to a new species, Homo floresiensis. The definition includes a mosaic of features, some like modern humans (hence derived: genus Homo), some like modern apes and australopithecines (hence primitive: not species sapiens), and some unique (hence new species: floresiensis). Conversely, because only modern humans (H. sapiens) are known in this region in the last 40 thousand years, these individuals have also been suggested to be genetic human dwarfs. Such dwarfs resemble small humans and do not show the mosaic combination of the most complete individuals, LB1 and LB6, so this idea has been largely dismissed. We have previously shown that some features of the cranium of hypothyroid cretins are like those of LB1. Here we examine cretin postcrania to see if they show anatomical mosaics like H. floresiensis. We find that hypothyroid cretins share at least 10 postcranial features with Homo floresiensis and unaffected humans not found in apes (or australopithecines when materials permit). They share with H. floresiensis, modern apes and australopithecines at least 11 postcranial features not found in unaffected humans. They share with H. floresiensis, at least 8 features not found in apes, australopithecines or unaffected humans. Sixteen features can be rendered metrically and multivariate analyses demonstrate that H. floresiensis co-locates with cretins, both being markedly separate from humans and chimpanzees (P<0.001: from analysis of similarity (ANOSIM) over all variables, ANOSIM, global R>0.999). We therefore conclude that LB1 and LB6, at least, are, most likely, endemic cretins from a population of unaffected Homo sapiens. This is consistent with recent hypothyroid endemic cretinism throughout Indonesia, including the nearby island of Bali. PMID:20885948

Oxnard, Charles; Obendorf, Peter J; Kefford, Ben J

2010-09-27

353

HomoSAR: Bridging comparative protein modeling with quantitative structural activity relationship to design new peptides.  

PubMed

Peptides play significant roles in the biological world. To optimize activity for a specific therapeutic target, peptide library synthesis is inevitable; which is a time consuming and expensive. Computational approaches provide a promising way to simply elucidate the structural basis in the design of new peptides. Earlier, we proposed a novel methodology termed HomoSAR to gain insight into the structure activity relationships underlying peptides. Based on an integrated approach, HomoSAR uses the principles of homology modeling in conjunction with the quantitative structural activity relationship formalism to predict and design new peptide sequences with the optimum activity. In the present study, we establish that the HomoSAR methodology can be universally applied to all classes of peptides irrespective of sequence length by studying HomoSAR on three peptide datasets viz., angiotensin-converting enzyme inhibitory peptides, CAMEL-s antibiotic peptides, and hAmphiphysin-1 SH3 domain binding peptides, using a set of descriptors related to the hydrophobic, steric, and electronic properties of the 20 natural amino acids. Models generated for all three datasets have statistically significant correlation coefficients (r(2) ) and predictive r2 (rpred?2) and cross validated coefficient ( qLOO?2). The daintiness of this technique lies in its simplicity and ability to extract all the information contained in the peptides to elucidate the underlying structure activity relationships. The difficulties of correlating both sequence diversity and variation in length of the peptides with their biological activity can be addressed. The study has been able to identify the preferred or detrimental nature of amino acids at specific positions in the peptide sequences. © 2013 Wiley Periodicals, Inc. PMID:24105965

Borkar, Mahesh R; Pissurlenkar, Raghuvir R S; Coutinho, Evans C

2013-09-18

354

A voyage into the synthesis and photophysics of homo- and heterobinuclear ensembles of phthalocyanines and porphyrins.  

PubMed

The remarkable properties of both phthalocyanines and porphyrins as individual building blocks have motivated the synthesis and study of homo- and heterobinuclear conjugates as light-harvesting systems. These planar chromophores share important electronic features such as high molar absorption coefficients, rich redox chemistry and interesting photoinduced energy and/or electron transfer abilities. In addition, some of these properties can be tuned by the introduction of different peripheral substituents and metal centres. In this review, we present relevant synthetic strategies for the preparation of covalent and supramolecular, homo- and heterobinuclear systems based on phthalocyanine and porphyrin chromophores, leading to a variety of architectures. In such systems, the degree of electronic interaction between the components is highly dependent on the electronic features of the two macrocycles, their linkage, and the molecular topology of the ensemble. In addition, incorporation of electroactive units into these binuclear systems has been pursued, affording multicomponent, donor-acceptor conjugates. In-depth photophysical characterization of the ground- and excited-state features of many of these homo- and heterobinuclear phthalocyanine and/or porphyrin ensembles has also been presented. Particular attention has been paid to understand the fundamental dynamics of the energy transfer and charge separation processes of these systems. This review intends to offer a general overview of the preparation of this class of compounds and the study of their photophysical properties which clearly show their potentiality as model compounds of light-harvesting complexes. PMID:23832123

de la Torre, Gema; Bottari, Giovanni; Sekita, Michael; Hausmann, Anita; Guldi, Dirk M; Torres, Tomás

2013-09-23

355

Synthesis, characterisation, monomer reactivity ratios and thermal stabilities of homo and copolymers of 4-nonylphenyl methacrylate with styrene  

Microsoft Academic Search

Purpose – To synthesise and characterise homo and copolymer of 4-nonylphenyl methacrylate (NPMA) and styrene and to determine monomer reactivity ratios by the application of conventional linearisation methods such as Finemann-Ross (F-R) and Kelen-Tudos (K-T) methods. Design\\/methodology\\/approach – New methacrylic monomer, NPMA with a pendant nonylphenyl group was copolymerised with styrene. All monomer and polymers (homo and copolymer) are characterised

H. Satapathy; A. K. Banthia

2007-01-01

356

Fossil Finds Expand Early Hominid Anatomy.  

ERIC Educational Resources Information Center

|Hominid fossils found in late 1990 in Ethiopia are reported. A controversy surrounding these remains and those of earlier expeditions, including Lucy, over whether more than one species of hominid are represented is discussed. (CW)|

Bower, B.

1991-01-01

357

How a Dinosaur Became a Fossil  

NSDL National Science Digital Library

This interactive resource adapted from the Museum of Paleontology at the University of California, Berkeley shows how a dinosaur can be buried under sediment after it dies, become a fossil, and then become exposed and discovered by paleontologists.

Foundation, Wgbh E.

2005-12-17

358

Fossil energy program. Progress report, July 1980  

SciTech Connect

This report - the seventy-second of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction projects, process and program analysis, fossil energy environmental analysis, coal preparation and waste utilization, coal preparation plant automation, atmospheric fluidized bed coal combustor for cogeneration, technical support to the TVA fluidized bed combustion demonstration plant program, fossil energy applications assessments, performance assurance system support for fossil energy projects, international assessment of atmospheric fluidized bed combustion technology, and PFBC systems analysis.

McNeese, L. E.

1980-10-01

359

Proceedings: 1990 fossil plant cycling conference  

SciTech Connect

Fossil plant cycling continues to be a key issue for many electric utilities. EPRI's previous cycling workshops, held in 1983, 1985, and 1987, allowed utilities to benefit from collective industry experience in the conversion of baseload fossil units to cyclic operation. Continued improvements in equipment, retrofits, diagnostics, and controls were highlighted at the 1990 conference. The objective is to provide a forum for utility discussions of the cycling operation of fossil fuel power plants. Potomac Electric Power Company (PEPCO) hosted the 1990 EPRI Fossil Fuel Cycling Conference in Washington, DC, on December 4--6, 1990. More than 130 representatives from utilities, vendors, government agencies, universities, and industry associations attended the conference. Following the general session, technical sessions covered such topics as plant modifications, utility retrofit experience, cycling economics, life assessment, controls, environmental controls, and energy storage. Attendees also toured PEPCO's Potomac River generating station, the site of an earlier EPRI cycling conversion study.

Not Available

1991-12-01

360

Fossil energy program. Progress report, August 1981  

SciTech Connect

This report - the eighty-fifth of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental programs, environmental control technology, coal preparation and waste utilization, atmospheric fluidized bed coal combustor for cogeneration, Tennessee Valley Authority Fluidized Bed Combustion demonstration plant program technical support, PFBC systems analysis, fossil fuel applications assessment, performance assurance system support for fossil energy projects, and international energy technology assessment.

McNeese, L.E.

1981-10-01

361

Palaeoenvironments of the Buia Homo site: High-resolution facies analysis and non-marine sequence stratigraphy in the Alat formation (Pleistocene Dandiero Basin, Danakil depression, Eritrea)  

Microsoft Academic Search

The Early to Middle Pleistocene Dandiero rift basin is located near the Buia village, 110km south of Massawa (Eritrea), and is filled by about 1000m of continental deposits bearing 1My erectus-like human remains. The basin fill consists of six formations (from bottom up): Bukra sand and gravels (fluvial), Alat formation (fluvio-lacustrine), Wara sand and gravel (fluvial), Goreya formation (lacustrine), Aro

Massimiliano Ghinassi; Yosief Libsekal; Mauro Papini; Lorenzo Rook

2009-01-01

362

International Organisation of Palaeobotany: Plant Fossil Record  

NSDL National Science Digital Library

Users are able to search an extensive database of information on the plant fossil record, including descriptions and occurrences of modern genera and fossil species. Searches can be performed in a variety of ways: by Genera, description, taxonomy, occurrences, and by palaeogeographic maps. After locating the specific plant of interest in the database, the occurrences of that plant are then displayed in a palaeogeographic map.

363

Fossil habrotrochid rotifers in Dominican amber  

Microsoft Academic Search

Flask-shaped microfossils are reported from bracts of a moss in Eocene-Oligocene amber from the northern Dominican Republic. These microfossils are identical with the thecae of certain living moss-dwelling rotifers in the genusHabrotrocha (Bdelloidea), which have previously been reported as fossils only from Holocene peat. What may be an egg and a rotifer body fossil are associated with these thecae and

B. M. Waggoner; G. O. Poinar

1993-01-01

364

Hydrogen and electricity from decarbonised fossil fuels  

Microsoft Academic Search

Hydrogen and electricity may become the favoured twin energy carriers in a possible “greenhouse driven” future due to their lack of CO2-emissions at the point of use. It is shown that decarbonising fossil fuels to hydrogen with CO2 being stored in deep geological formations represents the least expensive way of producing CO2-free hydrogen. For fossil fuels there seems to be

Olav Kaarstad; Harry Audus

1997-01-01

365

Quantifying Fossil Fuel CO 2 over Europe  

Microsoft Academic Search

Europe is responsible for more than 25% of global fossil fuel CO2 emissions (Marland et al. 2006), and these emissions account for about 30–50% of the observed CO2 variability in this region (see Sect. 4.2.1). To balance greenhouse gases over Europe, therefore, also requires quantification\\u000a of CO2 emissions from fossil fuel (i.e. coal, oil and natural gas) burning. Reliable continuous

Ingeborg Levin; Ute Karstens

366

Mexican Fossil Mammals, Who, Where and When?  

Microsoft Academic Search

Although the earliest report of a fossil mammal from Mexico dates from 1799, our knowledge of the group is still poor. The\\u000a Mexican mammalian fossil record is biased towards the large-sized taxa and younger ages.\\u000a \\u000a The mammalian record in Mexico ranges from the Jurassic to the Quaternary. Most of the Cenozoic epochs, except for the Paleocene,\\u000a have mammal bearing deposits.

Marisol Montellano-Ballesteros; Eduardo Jimenez-Hidalgo

367

Recent Human Evolution in East Asia and Australasia  

Microsoft Academic Search

In both East Asia and Australasia arguments for evolutionary continuity between middle-late Pleistocene hominid populations and modern Homo sapiens are of long standing. In both regions, however, problems of chronological distribution, dating and preservation of hominid skeletal materials provide an effective barrier to extending regional sequences back to `archaic' Homo sapiens or Homo erectus. The earliest securely dated modern Homo

Peter Brown

1992-01-01

368

A cranium for the earliest Europeans: phylogenetic position of the hominid from Ceprano, Italy.  

PubMed

The human fossil evidence unequivocally pertaining to the first inhabitants of Europe at present includes the sample from Atapuerca-TD6 (Spain) and the incomplete adult calvaria discovered near Ceprano, in Southern Latium (Italy). On the basis of regional correlations and a series of absolute dates, the age of the Ceprano hominid is estimated to range between 800 and 900 kilo-annum (ka). In addition, the association with archaic (Mode 1) Paleolithic findings from the same area is suggested. After the completed reconstruction of the calvaria, we present here a new study dealing with the general and more detailed aspects of the morphology displayed by Ceprano, in comparison to fossil samples ranging between Early and Middle Pleistocene. According to our results, cranial features indicate that Ceprano represents a unique morphological bridge between the clade Homo ergaster/erectus and later Middle Pleistocene specimens commonly referred to Homo heidelbergensis (and/or to Homo rhodesiensis), particularly those belonging to the African fossil record that ultimately relates to the origin of modern humans. In conclusion, given its geographical, chronological, and phylogenetic position, an attribution to the species Homo antecessor is considered, although the sample from Atapuerca-TD6 is not directly comparable to Ceprano. Alternatively, a new species-ancestral to later European and African hominines-should be named to accommodate such a unique fossil specimen. PMID:11504953

Manzi, G; Mallegni, F; Ascenzi, A

2001-08-14

369

A cranium for the earliest Europeans: Phylogenetic position of the hominid from Ceprano, Italy  

PubMed Central

The human fossil evidence unequivocally pertaining to the first inhabitants of Europe at present includes the sample from Atapuerca-TD6 (Spain) and the incomplete adult calvaria discovered near Ceprano, in Southern Latium (Italy). On the basis of regional correlations and a series of absolute dates, the age of the Ceprano hominid is estimated to range between 800 and 900 kilo-annum (ka). In addition, the association with archaic (Mode 1) Paleolithic findings from the same area is suggested. After the completed reconstruction of the calvaria, we present here a new study dealing with the general and more detailed aspects of the morphology displayed by Ceprano, in comparison to fossil samples ranging between Early and Middle Pleistocene. According to our results, cranial features indicate that Ceprano represents a unique morphological bridge between the clade Homo ergaster/erectus and later Middle Pleistocene specimens commonly referred to Homo heidelbergensis (and/or to Homo rhodesiensis), particularly those belonging to the African fossil record that ultimately relates to the origin of modern humans. In conclusion, given its geographical, chronological, and phylogenetic position, an attribution to the species Homo antecessor is considered, although the sample from Atapuerca-TD6 is not directly comparable to Ceprano. Alternatively, a new species—ancestral to later European and African hominines—should be named to accommodate such a unique fossil specimen.

Manzi, G.; Mallegni, F.; Ascenzi, A.

2001-01-01

370

Early Origin for Human-Like Precision Grasping: A Comparative Study of Pollical Distal Phalanges in Fossil Hominins  

PubMed Central

Background The morphology of human pollical distal phalanges (PDP) closely reflects the adaptation of human hands for refined precision grip with pad-to-pad contact. The presence of these precision grip-related traits in the PDP of fossil hominins has been related to human-like hand proportions (i.e. short hands with a long thumb) enabling the thumb and finger pads to contact. Although this has been traditionally linked to the appearance of stone tool-making, the alternative hypothesis of an earlier origin—related to the freeing of the hands thanks to the advent of terrestrial bipedalism—is also possible given the human-like intrinsic hand proportion found in australopiths. Methodology/Principal Findings We perform morphofunctional and morphometric (bivariate and multivariate) analyses of most available hominin pollical distal phalanges, including Orrorin, Australopithecus, Paranthropous and fossil Homo, in order to investigate their morphological affinities. Our results indicate that the thumb morphology of the early biped Orrorin is more human-like than that of australopiths, in spite of its ancient chronology (ca. 6 Ma). Moreover, Orrorin already displays typical human-like features related to precision grasping. Conclusions These results reinforce previous hypotheses relating the origin of refined manipulation of natural objects–not stone tool-making–with the relaxation of locomotor selection pressures on the forelimbs. This suggests that human hand length proportions are largely plesiomorphic, in the sense that they more closely resemble the relatively short-handed Miocene apes than the elongated hand pattern of extant hominoids. With the advent of terrestrial bipedalism, these hand proportions may have been co-opted by early hominins for enhanced manipulative capabilities that, in turn, would have been later co-opted for stone tool-making in the genus Homo, more encephalized than the previous australopiths. This hypothesis remains may be further tested by the finding of more complete hands of unequivocally biped early hominins.

Almecija, Sergio; Moya-Sola, Salvador; Alba, David M.

2010-01-01

371

Body size and its consequences: allometry and the lower limb length of Liang Bua 1 (Homo floresiensis).  

PubMed

Bivariate femoral length allometry in recent humans, Pan, and Gorilla is investigated with special reference to the diminutive Liang Bua (LB) 1 specimen (the holotype of Homo floresiensis) and six early Pleistocene femora referred to the genus Homo. Relative to predicted body mass, Pan and Gorilla femora show strong negative length allometry while recent human femora evince isometry to positive allometry, depending on sample composition and line-fitting technique employed. The allometric trajectories of Pan and Homo show convergence near the small body size range of LB 1, such that LB 1 manifests a low percentage deviation (d(yx) of Smith [1980]) from the Pan allometric trajectory and falls well within the 95% confidence limits around the Pan individuals (but also outside the 95% confidence limits for recent Homo). In contrast, the six early Pleistocene Homo femora, belonging to larger individuals, show much greater d(yx) values from both Pan and Gorilla and fall well above the 95% confidence limits for these taxa. All but one of these Pleistocene Homo specimens falls within the 95% confidence limits of the recent human sample. Similar results are obtained when femoral length is regressed on femoral head diameter in unlogged bivariate space. Regardless of the ultimate taxonomic status of LB 1, these findings are consistent with a prediction made by us (Franciscus and Holliday, 1992) that hominins in the small body size range of A.L. 288-1 ("Lucy"), including members of the genus Homo, will tend to possess short, ape-like lower limbs as a function of body size scaling. PMID:19674770

Holliday, Trenton W; Franciscus, Robert G

2009-08-11

372

The problems and potential of using animal fossils and trace fossils in terminal Proterozoic biostratigraphy  

Microsoft Academic Search

Despite the discovery of soft-bodied megascopic fossils of late Neoproterozoic age at numerous localities world-wide, there has been slow acceptance of their potential for intercontinental correlation. The stratigraphic thickness of sediments separating individual occurrences of such fossils from the base of the Cambrian is very varied. Basic questions have also been posed as to the classification of the organisms represented

Richard J. F. Jenkins

1995-01-01

373

Functional consequences of homo- but not hetero-oligomerization between transporters for the biogenic amine neurotransmitters.  

PubMed

Before this study, the human norepinephrine transporter (hNET) was the only member of the biogenic amine neurotransmitter transporter family that had not been demonstrated to be a functional homo-oligomer. Here, using two forms of the transporter, I155C and hNET-myc, with distinct antigenicity and inhibitor sensitivity, we demonstrated that hNET exists as a homo-oligomer. hNET I155C is a functional mutant and is sensitive to inactivation by the sulfhydryl reagent [2-(trimethylammonium)ethyl]methanethiosulfonate, while hNET-myc is resistant to inactivation by this reagent. Coimmunoprecipitation of these two forms demonstrated that a physical interaction exists between norepinephrine transporter monomers. Further characterization of this physical interaction has revealed that the activity of norepinephrine transporters depends on interactions between monomers. Because norepinephrine transporters and serotonin transporters are the only two members of the neurotransmitter transporter family endogenously expressed in the cell membrane of the same cells, placental syncytiotrophoblasts, we tested the ability of norepinephrine transporters and serotonin transporters to associate and function in a hetero-oligomeric form. Similarly, coexpression of hNET-myc with serotonin transporter-FLAG showed a physical interaction in coimmunoprecipitation assays. However, coexpression of serotonin and norepinephrine transporters did not sensitize norepinephrine transporter activity to inhibition by citalopram, a selective serotonin transport inhibitor. Thus, the norepinephrine transporter-serotonin transporter physical association did not produce functional consequences. Based on this, we propose that the transporters for biogenic amine neurotransmitters interact functionally in homo- but not hetero-oligomeric forms. PMID:12787070

Kocabas, A M; Rudnick, G; Kilic, F

2003-06-01

374

Pygmoid Australomelanesian Homo sapiens skeletal remains from Liang Bua, Flores: Population affinities and pathological abnormalities  

PubMed Central

Liang Bua 1 (LB1) exhibits marked craniofacial and postcranial asymmetries and other indicators of abnormal growth and development. Anomalies aside, 140 cranial features place LB1 within modern human ranges of variation, resembling Australomelanesian populations. Mandibular and dental features of LB1 and LB6/1 either show no substantial deviation from modern Homo sapiens or share features (receding chins and rotated premolars) with Rampasasa pygmies now living near Liang Bua Cave. We propose that LB1 is drawn from an earlier pygmy H. sapiens population but individually shows signs of a developmental abnormality, including microcephaly. Additional mandibular and postcranial remains from the site share small body size but not microcephaly.

Jacob, T.; Indriati, E.; Soejono, R. P.; Hsu, K.; Frayer, D. W.; Eckhardt, R. B.; Kuperavage, A. J.; Thorne, A.; Henneberg, M.

2006-01-01

375

"Homo High"  

ERIC Educational Resources Information Center

In Chicago's public school system, LGBT students were three times more likely than straight peers to miss school because of threats to their safety, according to 2003 districtwide survey; and students who face regular harassment were more like to drop out. In this article, the author shares her thoughts on the move of Chicago school officials to…

Kilman, Carrie

2010-01-01

376

Education Program on Fossil Resources Including Coal  

NASA Astrophysics Data System (ADS)

Fossil fuels including coal play a key role as crucial energies in contributing to economic development in Asia. On the other hand, its limited quantity and the environmental problems causing from its usage have become a serious global issue and a countermeasure to solve such problems is very much demanded. Along with the pursuit of sustainable development, environmentally-friendly use of highly efficient fossil resources should be therefore, accompanied. Kyushu-university?s sophisticated research through long years of accumulated experience on the fossil resources and environmental sectors together with the advanced large-scale commercial and empirical equipments will enable us to foster cooperative research and provide internship program for the future researchers. Then, this program is executed as a consignment business from the Ministry of Economy, Trade and Industry from 2007 fiscal year to 2009 fiscal year. The lecture that uses the textbooks developed by this program is scheduled to be started a course in fiscal year 2010.

Usami, Masahiro

377

How Do Scientists Find Dinosaur Fossils?  

NSDL National Science Digital Library

This lesson plan is about the process by which paleontologists locate, excavate, and study dinosaurs. Students will write journal entries pretending they are on a dinosaur dig. They will also make fact sheets about this recently discovered Jobaria dinosaur; place Jobaria into a timeline to indicate the periods in which it lived; visit a website to learn about the steps involved in finding and excavating dinosaur fossils, then list these steps and explain their importance; describe what the bones in an interactive Jobaria skeleton indicate about this dinosaur; and view pictures of a trip teenagers took to look for dinosaur fossils.

378

Brachiopod exercise for FossilPlot  

NSDL National Science Digital Library

Students are taught how to use FossilPlot software in the lab prior to this exercise. Students work individual to work through the short exercise, handing in a copy of the diversity graphs for the brachiopod orders (which will be tested in the following midterm) and a completed worksheet. The exercise reinforces the main functions of FossilPlot and addresses basic concepts on diversity and biostratigraphy. Once the assignments are collected and graded, we discuss the outcomes of the exercise in class.

Tapanila, Leif

379

Fossils: An Ancient Sea in Indiana  

NSDL National Science Digital Library

Paleontologists have been remarkably successful in determining what earlier life forms looked like, as well as how they probably behaved when alive. This interactive feature illustrates a slab of rock containing fossils of several types of creatures that once inhabited the Borden Sea, over 300 million years ago in what is now central Indiana. Clicking on highlighted fossils accesses animations of what they may have looked like in life, along with a brief description of the organism. Reconstructions such as these have given scientists insight into evolutionary processes and trends. A background essay and discussion questions are included.

2011-05-09

380

Fossils, Genes and The Origin of Organs  

ScienceCinema

A toolkit of experimental and comparative biology can be applied to understand the great transformations in the history of life. Expeditionary paleontology can be used to target key nodes of the tree of life for which new fossils can provide insights into major morphological transformations. These fossils often have intermediate conditions that allow extant creatures to be compared in new ways. The tools of developmental genetics can then be used to explore these new comparisons to understand the genetic basis for macroevolutionary change. These different approaches can be used to predict new discoveries and this is only possible because of the empirical content of the tree of life.

381

Fossils: An Ancient Sea in Indiana  

NSDL National Science Digital Library

Paleontologists have been remarkably successful in determining what earlier life forms looked like, as well as how they probably behaved when alive. This interactive feature illustrates a slab of rock containing fossils of several types of creatures that once inhabited the Borden Sea, over 300 million years ago in what is now central Indiana. Clicking on highlighted fossils accesses animations of what they may have looked like in life, along with a brief description of the organism. Reconstructions such as these have given scientists insight into evolutionary processes and trends. A background essay and discussion questions are included.

382

Relationship between cusp size and occlusal wear pattern in Neanderthal and Homo sapiens first maxillary molars.  

PubMed

Tooth wear studies in mammals have highlighted the relationship between wear facets (attritional areas produced during occlusion by the contact between opposing teeth) and physical properties of the ingested food. However, little is known about the influence of tooth morphology on the formation of occlusal wear facets. We analyzed the occlusal wear patterns of first maxillary molars (M(1) s) in Neanderthals, early Homo sapiens, and contemporary modern humans. We applied a virtual method to analyze wear facets on the crown surface of three-dimensional digital models. Absolute and relative wear facet areas are compared with cusp area and cusp height. Although the development of wear facets partially follows the cusp pattern, the results obtained from the between-group comparisons do not reflect the cusp size differences characterizing these groups. In particular, the wear facets developed along the slopes of the most discriminate cusp between Neanderthals and Homo sapiens (hypocone) do not display any significant difference. Moreover, no correlations have been found between cusp size and wear facet areas (with the exception of the modern sample) and between cusp height and wear facet areas. Our results suggest that cusp size is only weakly related to the formation of the occlusal wear facets. Other factors, such as, diet, food processing, environmental abrasiveness, and nondietary habits are probably more important for the development and enlargement of wear facets, corroborating the hypotheses suggested from previous dental wear studies. PMID:21337711

Fiorenza, Luca; Benazzi, Stefano; Viola, Bence; Kullmer, Ottmar; Schrenk, Friedemann

2010-12-31

383

Nasal septal and premaxillary developmental integration: implications for facial reduction in Homo.  

PubMed

The influence of the chondrocranium in craniofacial development and its role in the reduction of facial size and projection in the genus Homo is incompletely understood. As one component of the chondrocranium, the nasal septum has been argued to play a significant role in human midfacial growth, particularly with respect to its interaction with the premaxilla during prenatal and early postnatal development. Thus, understanding the precise role of nasal septal growth on the facial skeleton is potentially informative with respect to the evolutionary change in craniofacial form. In this study, we assessed the integrative effects of the nasal septum and premaxilla by experimentally reducing facial length in Sus scrofa via circummaxillary suture fixation. Following from the nasal septal-traction model, we tested the following hypotheses: (1) facial growth restriction produces no change in nasal septum length; and (2) restriction of facial length produces compensatory premaxillary growth due to continued nasal septal growth. With respect to hypothesis 1, we found no significant differences in septum length (using the vomer as a proxy) in our experimental (n = 10), control (n = 9) and surgical sham (n = 9) trial groups. With respect to hypothesis 2, the experimental group exhibited a significant increase in premaxilla length. Our hypotheses were further supported by multivariate geometric morphometric analysis and support an integrative relationship between the nasal septum and premaxilla. Thus, continued assessment of the growth and integration of the nasal septum and premaxilla is potentially informative regarding the complex developmental mechanisms that underlie facial reduction in genus Homo evolution. PMID:21157917

Holton, Nathan E; Franciscus, Robert G; Marshall, Steven D; Southard, Thomas E; Nieves, Mary Ann

2010-11-12

384

Early Pleistocene 40Ar/39Ar ages for Bapang Formation hominins, Central Jawa, Indonesia  

PubMed Central

The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the Solo basin of Central Jawa. The dome has yielded nearly 80 Homo erectus fossils, around 50 of which have known findspots. With a hornblende 40Ar/39Ar plateau age of 1.66 ± 0.04 mega-annum (Ma) reportedly associated with two fossils [Swisher, C.C., III, Curtis, G. H., Jacob, T., Getty, A. G., Suprijo, A. & Widiasmoro (1994) Science 263, 1118–1121), the dome offers evidence that early Homo dispersed to East Asia during the earliest Pleistocene. Unfortunately, the hornblende pumice was sampled at Jokotingkir Hill, a central locality with complex lithostratigraphic deformation and dubious specimen provenance. To address the antiquity of Sangiran H. erectus more systematically, we investigate the sedimentary framework and hornblende 40Ar/39Ar age for volcanic deposits in the southeast quadrant of the dome. In this sector, Bapang (Kabuh) sediments have their largest exposure, least deformation, and most complete tephrostratigraphy. At five locations, we identify a sequence of sedimentary cycles in which H. erectus fossils are associated with epiclastic pumice. From sampled pumice, eight hornblende separates produced 40Ar/39Ar plateau ages ranging from 1.51 ± 0.08 Ma at the Bapang/Sangiran Formation contact, to 1.02 ± 0.06 Ma, at a point above the hominin-bearing sequence. The chronological sequence of 40Ar/39Ar ages follows stratigraphic order across the southeast quadrant. An intermediate level yielding four nearly complete crania has an age of about 1.25 Ma.

Larick, Roy; Ciochon, Russell L.; Zaim, Yahdi; Sudijono; Suminto; Rizal, Yan; Aziz, Fachroel; Reagan, Mark; Heizler, Matthew

2001-01-01

385

From fossil fuels to renewable energies  

Microsoft Academic Search

This paper describes the model of an industrial society based on fossil fuels whose supply decreases and the society is forced to develop alternative energy sources. It is conceived as an abstract model that captures the basic aspect of such a change, but in a simple and schematic way. Despite this, most of the important dynamics of this problem are

Margarita Mediavilla; Luis Javier Miguel; Carlos de Castro

386

Fossils of reionization in the local group  

SciTech Connect

We use a combination of high-resolution gas dynamics simulations of high-redshift dwarf galaxies and dissipationless simulations of a Milky Way sized halo to estimate the expected abundance and spatial distribution of the dwarf satellite galaxies that formed most of their stars around z {approx} 8 and evolved only little since then. Such galaxies can be considered as fossils of the reionization era, and studying their properties could provide a direct window into the early, pre-reionization stages of galaxy formation. We show that 5-15% of the objects existing at z {approx} 8 do indeed survive until the present in the MW like environment without significant evolution. This implies that it is plausible that the fossil dwarf galaxies do exist in the Local Group. Because such galaxies form their stellar systems early during the period of active merging and accretion, they should have spheroidal morphology regardless of their current distance from the host galaxy. We show that both the expected luminosity function and spatial distribution of dark matter halos which are likely to host fossil galaxies agree reasonably well with the observed distributions of the luminous (L{sub V} > 10{sup 6} Lsun) Local Group fossil candidates near the host galaxy (d<200 kpc). However, the predicted abundance is substantially larger (by a factor of 2-3) for fainter galaxies (L{sub V} < 10{sup 6} Lsun) at larger distances (d>300 kpc). We discuss several possible explanations for this discrepancy.

Gnedin, Nickolay Y.; /Fermilab /KICP, Chicago /Chicago U., EFI; Kravtsov, Andrey V.; /KICP, Chicago /Chicago U., EFI /Chicago U., Astron. Astrophys. Ctr.

2006-01-01

387

Learning about Fossil Formation by Classroom Simulation.  

ERIC Educational Resources Information Center

|Activities in which students build their own simulations of fossils, using seashells, chicken bones, toy dinosaurs, or leaves as models and plaster of paris, sand, mud, clay, or a mixture of gravel and clay as a matrix are presented. Curriculum extensions are included. (KR)|

Schlenker, Richard M.; Yoshida, Sarah J.

1991-01-01

388

The Fascinating Story of Fossil Fuels  

ERIC Educational Resources Information Center

|How this energy source was created, its meaning to mankind, our drastically reduced supply, and why we cannot wait for nature to make more are considered. Today fossil fuels supply 96 percent of the energy used but we must find alternate energy options if we are to combat the energy crisis. (BL)|

Asimov, Isaac

1973-01-01

389

Cliffwood Beach Fossil Preserve Environmental Assessment.  

National Technical Information Service (NTIS)

The Fossil Preserve built as part of the Cliffwood Beach Shore Protection project in the mid 1970's is important to scientists. The Township of Aberdeen now wants the Preserve filled to halt further cliff erosion and avoid safety problems. Before filling ...

1982-01-01

390

Insect Diversity in the Fossil Record  

Microsoft Academic Search

Insects possess a surprisingly extensive fossil record. Compilation of the geochronologic ranges of insect families demonstrates that their diversity exceeds that of preserved vertebrate tetrapods through 91 percent of their evolutionary history. The great diversity of insects was achieved not by high origination rates but rather by low extinction rates comparable to the low rates of slowly evolving marine invertebrate

Conrad C. Labandeira; J. John Sepkoski Jr.

1993-01-01

391

Stellar Populations of Fossil Group Galaxies  

Microsoft Academic Search

Fossil groups are thought to be the remnants of groups of galaxies in which all the component galaxies have merged. Left behind is one, large, elliptical galaxy (sometimes surrounded by faint remnants of the group), which has a mass and X-ray luminosity comparable to an entire group of galaxies. It is thought that these objects are the end state of

Naomi Pequette; K. Alexander; E. M. Wilcots

2011-01-01

392

Colloidal and polymeric nature of fossil amber  

Microsoft Academic Search

Fossilized ambers from several geographical origins, copal from the Kauri pine tree of New Zealand and modern white spruce tree resin have been analyzed by the following analytical techniques: dynamic light scattering, optical and scanning electron microscopy, gel permeation chromatography, IR spectroscopy, rheology and viscometry. The results dispute the prevailing view that amber is largely an insoluble, continuously crosslinked, integral

Douglas Gold; Benjamin Hazen; Wilmer G. Miller

1999-01-01

393

Dental remains of fossil elephants from Turkey  

Microsoft Academic Search

Turkey is at the crossroads of Africa, Asia and Europe, and occupies an important position for the migration of mammals such as elephantids. Nonetheless, there has been no detailed study of fossil elephants from Turkey. In this study, elephant remains from five localities were examined. Mammuthus meridionalis, Mammuthus trogontherii, Elephas maximus and probably Palaeoloxodon antiquus were identified. M. meridionalis remains from

Ebru Albayrak; Adrian M. Lister

394

Advanced Fossil Energy Technologies: Current reports  

SciTech Connect

Advanced Fossil Energy Technologies (FET) is designed to keep fossil energy researchers informed of the latest scientific and technical reports in their area. The publication announces all DOE-sponsored reports and patent applications in the subject scope of fossil energy that have been received and processed into the Energy Data Base (EDB) in a two-week period prior to the publication date of FET. It covers information on coal, petroleum, natural gas, fuel cells, heat engines, and magnetohydrodynamics. The digests in FET and other citations to information on fossil energy back to 1974 are available for on-line searching and retrieval on EDB. Current information, added daily to EDB, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs. The entire EDB is available on commercial on-line retrieval systems. Another consideration in the development of FET was to provide a convenient and cost-effective method for researchers to obtain printed copies of these reports.

Tamura, A.T. (ed.)

1988-01-15

395

Mass Extinctions in the Marine Fossil Record  

Microsoft Academic Search

A new compilation of fossil data on invertebrate and vertebrate families indicates that four mass extinctions in the marine realm are statistically distinct from background extinction levels. These four occurred late in the Ordovician, Permian, Triassic, and Cretaceous periods. A fifth extinction event in the Devonian stands out from the background but is not statistically significant in these data. Background

David M. Raup; J. John Sepkoski

1982-01-01

396

From Fossils to Facts to Stories.  

ERIC Educational Resources Information Center

Eight steps are outlined for presenting a combined science/language experience unit to primary students, in which the children observe and discuss a phenomenon and dictate a group report. Sample projects with fossils, magnets, and air pressure are described. (SJL)

Hungerford, Harold R.; Steinruck, Yvonne Siv

1978-01-01

397

Future role of fossil fuels. [Conference paper  

Microsoft Academic Search

The Federal budget request for fossil-energy R and D passed the $1 billion mark in fiscal year 1981, but that is only a little over 1% of the sum spent to buy foreign oil. Coal and conservation offer the best transition to an oil-independent era. New policies to expand the use of coal include the Fuel Use Act of 1978

LeGassie

1980-01-01

398

The Fascinating Story of Fossil Fuels  

ERIC Educational Resources Information Center

How this energy source was created, its meaning to mankind, our drastically reduced supply, and why we cannot wait for nature to make more are considered. Today fossil fuels supply 96 percent of the energy used but we must find alternate energy options if we are to combat the energy crisis. (BL)

Asimov, Isaac

1973-01-01

399

Fossil Energy Materials Program conference proceedings  

SciTech Connect

The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Program to fulfill that responsibility. In addition to the AR and TD Materials Program, which is designed to address in a generic way the materials needs of fossil energy systems, specific materials support activities are also sponsored by the various line organizations such as the Office of Coal Gasification. A conference was held at Oak Ridge, Tennessee on May 19-21, 1987, to present and discuss the results of program activities during the past year. The conference program was organized in accordance with the research thrust areas we have established. These research thrust areas include structural ceramics (particularly fiber-reinforced ceramic composites), corrosion and erosion, and alloy development and mechanical properties. Eighty-six people attended the conference. Papers have been entered individually into EDB and ERA. (LTN)

Judkins, R.R. (comp.)

1987-08-01

400

Thermal dissolution of solid fossil fuels  

SciTech Connect

The use of oil shales and coals in the processes of thermal dissolution is considered. It is shown that thermal dissolution is a mode of liquefaction of solid fossil fuels and can be used both independently and in combination with liquefaction of coals and processing of heavy petroleum residues.

E.G. Gorlov [Institute for Fossil Fuels, Moscow (Russian Federation)

2007-10-15

401

Assuring the performance of fossil energy programs  

Microsoft Academic Search

In an effort to achieve timely commercialization, ERDA\\/Fossil Energy has developed the Performance Assurance System (PAS), a technique for reducing uncertainties in the economics of proposed processes and improving plant and component operability. PAS aids the decision making functions of ERDA program managers and industrial contractors through systematic application of standardized data collection and exchange procedures, analytical methods, mathematical models

S. S. Canja

1977-01-01

402

Australia poised for fossil fuel boom  

Microsoft Academic Search

Fossil fuels will dominate the energy consumption usage in Australia for ; years. Natural gas is expected to increase to 20.8% by the year 2000 from 4.5% ; presently. From 1971 to 2000, gasolines and other fuels should remain at about ; the same proportion of the total, middle distillates almost double from 20.6% to ; 40.6%, and the heavy

1974-01-01

403

Palaeomagnetic analysis of the Sterkfontein palaeocave deposits: implications for the age of the hominin fossils and stone tool industries.  

PubMed

Palaeomagnetic analysis was conducted on speleothems from Members 1-5 at Sterkfontein Cave, South Africa. Palaeomagnetic analysis of siltstone and speleothem from the bulk of Member 4 indicate a reversed magnetic polarity that dates the deposits and its Australopithecus africanus fossils to between 2.58 and ~2.16 Ma. Further confirmation of this age comes in the form of two short normal polarity events correlated to the Rèunion (~2.16 Ma) and Huckleberry Ridge (~2.05 Ma) events in speleothem capping the bulk of Member 4 and coeval with deposition of the final phase of Member 4, including A. africanus fossil Sts 5. At ~2.16-2.05 Ma, Sts 5 is the youngest representative of A. africanus yet discovered. Palaeomagnetic analysis of the Silberberg Grotto deposits identifies a single short geomagnetic field event in flowstone overlying the StW 573 Australopithecus fossil, which is suggested to represent the Rèunion event at ~2.16 Ma. This further supports the uranium lead age estimates of 2.3-2.2 Ma for the StW 573 fossil. Based on a reversed polarity for the deposits below the skeleton it cannot be older than 2.58 Ma. If StW 573 is considered to be a second species of Australopithecus then this indicates that two species of Australopithecus are present at Sterkfontein between 2.6 and 2.0 Ma. All of the Member 5 deposits date to less than 1.8 Ma based on a comparison of palaeomagnetic, faunal, and electron spin resonance age estimates. The StW 53 fossil bearing infill (M5A) is intermediate in age between Member 4 and the rest of Member 5 (B-C) at around 1.78-1.49 Ma. The rest of Member 5 (B-C) containing Oldowan and Acheulian stone tools and Homo and Paranthropus fossils was deposited gradually between 1.40 and 1.07 Ma, much younger than previously suggested. PMID:21392817

Herries, Andy I R; Shaw, John

2011-05-01

404

Exceptional fossil preservation and the cambrian explosion.  

PubMed

Exceptionally preserved, non-biomineralizing fossils contribute importantly to resolving details of the Cambrian explosion, but little to its overall patterns. Six distinct "types" of exceptional preservation are identified for the terminal Proterozoic-Cambrian interval, each of which is dependent on particular taphonomic circumstances, typically restricted both in space and time. Taphonomic pathways yielding exceptional preservation were particularly variable through the Proterozoic-Cambrian transition, at least in part a consequence of contemporaneous evolutionary innovations. Combined with the reasonably continuous record of "Doushantuo-type preservation," and the fundamentally more robust records of shelly fossils, phytoplankton cysts and trace fossils, these taphonomic perturbations contribute to the documentation of major evolutionary and biogeochemical shifts through the terminal Proterozoic and early Cambrian.Appreciation of the relationship between taphonomic pathway and fossil expression serves as a useful tool for interpreting exceptionally preserved, often problematic, early Cambrian fossils. In shale facies, for example, flattened non-biomineralizing structures typically represent the remains of degradation-resistant acellular and extracellular "tissues" such as chaetae and cuticles, whereas three-dimensional preservation represents labile cellular tissues with a propensity for attracting and precipitating early diagenetic minerals. Such distinction helps to identify the acuticular integument of hyolithids, the chaetae-like nature of Wiwaxia sclerites, the chaetognath-like integument of Amiskwia, the midgut glands of various Burgess Shale arthropods, and the misidentification of deposit-feeding arthropods in the Chengjiang biota. By the same reasoning, putative lobopods in the Sirius Passet biota and putative deuterostomes in the Chengiang biota are better interpreted as arthropods. PMID:21680421

Butterfield, Nicholas J

2003-02-01

405

A probabilistic approach to the craniometric variability of the genus Homo and inferences on the taxonomic affinities of the first human population dispersing out of Africa  

Microsoft Academic Search

There is probably no paleoanthropological issue with deeper disagreements than the taxonomic status of the Early–Middle Pleistocene members of the genus Homo One reason could be the difficulty of estimating the relationship between morphological and taxonomic diversity. In an attempt to contribute new evidence to this debate, bootstrapping techniques are used for analyzing the cranial variability of Homo. The results

Juan Manuel Jiménez-Arenas; Paul Palmqvist; Juan A. Pérez-Claros

406

Synthesis, structure, and functionalization of homo heterocalix[2]arene[2]triazines: versatile conformation and cavity structures regulated by the bridging elements.  

PubMed

A number of homo[2] and homo[4] heterocalix[2]arene[2]triazines were synthesized through a general and good-yielding fragment coupling approach starting from cyanuric halides, aromatic and aliphatic diols, and diamines under very mild reaction conditions. While homo[2] tetraazacalix[2]arene[2]triazine gave a twisted and pinched 1,2-alternate conformer, almost all homo[2] heterocalix[2]arene[2]triazines adopted different partial cone conformations in the solid state. Homo[4] heterocalix[2]arene[2]triazines yielded more diverse conformational structures including partial cone, pinched partial cone, 1,2-alternate and twisted 1,2-alternate, depending on the nature of bridging moieties. On the basis of (1)H NMR spectra, homo[2] and homo[4] heterocalix[2]arene[2]triazines were fluxional macrocycles in solution, and they underwent rapid conformation interconversion at different temperatures. Efficient and straightforward nucleophilic aromatic substitution reaction and palladium-catalyzed cross-coupling reactions on chlorotriazine rings, and the nucleophilic alkylation reaction on the bridging nitrogen atoms led to the construction of various highly functionalized homo heterocalix[2]arene[2]triazine derivatives. PMID:20443614

Chen, Yin; Wang, De-Xian; Huang, Zhi-Tang; Wang, Mei-Xiang

2010-06-01

407

Mössbauer effect study of a pleistocenic Brazilian fossil  

NASA Astrophysics Data System (ADS)

Some preliminary Mössbauer effect results for a pleistocenic bone fossilized by mineralization process are presented. The presence of some iron-sulphur compounds permits to infer a correlation between the oxidation state of iron and the environmental conditions of fossilization.

de Araújo, J. H.; Kunrath, J. I.; da Costa, M. I.; Vasquez, A.; Alves, C.; Dantas de Oliveira, L. D.

1991-11-01

408

Models of diffusion-limited uptake of trace elements in fossils and rates of fossilization  

NASA Astrophysics Data System (ADS)

Many fossils are assumed to take up trace elements by a process of combined diffusion plus adsorption (DA), yet in principle composition profiles can be explained by several different diffusion-limited processes, including diffusion plus reaction or recrystallization (DR) and double-medium diffusion (DMD). The DA and DMD models are supported by REE and U composition profiles across fossil teeth, measured by laser-ablation ICP-MS, that show error-function - like diffusion profiles into enamel from the dentine-enamel interface and concentrations in the interior of enamel that are at original biogenic levels or higher. Published composition and age profiles in some Pleistocene bones may be better explained by a DR model. All three diffusion models imply linear behavior between age and distance squared, vastly simplifying U-series dating methods for Pleistocene fossils. Modeled uptake rates for fossil teeth yield a strict minimum bound on durations of about one decade to one century. The similarity of diffusion profiles in teeth, irrespective of depositional ages ranging from ˜30 ka to >30 Ma, implies that uptake occurred quickly, with a maximum duration of a few tens of kyr for typical fossil enamel; faster uptake is implied for typical fossil bone and dentine. Disparities in these uptake estimates compared to some archeological bone may reflect sampling and preservation bias for paleontological vs. archeological materials.

Kohn, Matthew J.

2008-08-01

409

Contrasted fossil spreading centers off Baja California  

NASA Astrophysics Data System (ADS)

In April 2002, R/V L Atalante collected swath-bathymetry, surface and deep tow magnetic, gravity and seismic data in order to investigate the existence, characteristics and age of the Guadalupe and Magdalena fossil spreading centers that were postulated off Baja California (eastern Pacific Ocean). The new data confirm the existence of these extinct spreading centers and better define the location and orientation of the Magdalena Ridge segments. The two fossil ridges exhibit very different characters. The Guadalupe fossil axis displays a deep N-S axial valley with a 2D geometry, and regular abyssal hills and magnetic anomalies on its flanks. According to surface and deep tow magnetics, seafloor spreading stopped at 12 Ma (anomaly 5A). Conversely, the Magdalena fossil spreading system exhibits a complex bathymetric structure, with a series of ridge segments and conjugate fan-shaped abyssal hills, troughs and volcanic highs, and spreading discontinuities with various orientation. The surface and deep-tow magnetics indicate an age younger than or equal to 12 Ma, 5A being the youngest unambiguously identified magnetic anomaly. The morphological and structural difference between the two fossil spreading centers is striking. We interpret the fan-shaped abyssal hills and the various structural direction of the Magdalena spreading system as the result of a continuous clockwise change in spreading direction of about 18deg./Ma, for a total of 45deg. between anomalies 5B and 5A. Spreading finally ceased when the seafloor spreading direction became parallel to the margin. We believe that then, a new strike-slip plate boundary initiated along the western margin of Baja California. The Guadalupe ridge gradually slowed down with a minor 10deg. reorientation prior to extinction at chron 5A. This observation suggests that a Magdalena plate and a Guadalupe plate started to behave independently at about 14.5 Ma, with the Shirley FZ (27.6N) acting as a plate boundary. Whether there were time enough for a slow spreading center to establish on the now-subducted part of the Shirley FZ is unknown. Either such a subducted fossil spreading center or the subducted broken fracture zone could create an asthenospheric windows which would be at the origin of the peculiar volcanic rocks observed on land in Baja California.

Dyment, J.; Michaud, F.; Royer, J. Y.; Bourgois, J.; Sichler, B.; Bandy, W.; Mortera, C.; Sosson, M.; Pontoise, B.; Calmus, T.

2003-04-01

410

Cranial vault shape in fossil hominids: Fourier descriptors in norma lateralis.  

PubMed

Two major views of human evolution have elicited considerable controversy. These are: [1] the "out of Africa" hypothesis and [2] the "multiregional" hypothesis. This paper is an attempt to try to reconcile these two scenarios using hominid cranial vault data. Elliptical Fourier functions (EFFs) were used to describe, in visual and numerical terms, the shape of the human cranial vault in norma lateralis. Using jpeg images, contours of the cranial vault of a large sample of hominid specimens were pre-processed in Photoshop CS and rotated in 2D space (positional-orientation) so that a line drawn from nasion to porion was horizontal. The cranial vault image was then digitized with 72 closely-spaced points and submitted to a specially written routine that computed EFFs normalized by scaling (size-standardization). This ensured that the representation was invariant with respect to starting point, size and orientation. Statistically significant differences were found between the H. sapiens sample and both the H. erectus and H. neanderthalensis samples. In contrast, there were no statistically significant differences between the H. erectus and H. neanderthalensis groups, leading to three conclusions: [1] the similarity in cranial vault shape between H. erectus and H. neanderthalensis suggests a single gradually evolving lineage; [2] The taxon H. heidelbergensis can be embedded into the H. erectus?H. neanderthalensis line; and [3] H. sapiens seems to be a separate evolutionary development and is considered here either as a separate species or as a possible example of an allopatric semispecies (Grant, 1977). The results here suggest that human evolution over the last 2 Ma may turn out to be neither totally multiregional or simply out of Africa but rather represents a considerably more complicated picture. PMID:20801442

Lestrel, P E; Ohtsuki, F; Wolfe, C A

2010-10-01

411

A Mossbauer effect of study of plant and animal fossils  

Microsoft Academic Search

Mossbauer effect (ME) spectroscopy is applied to the study of the mechanism of fossilization process and the effect of environmental conditions on plant and animal fossils. The samples are collected near the Mediterranean Sea in Egypt and Libya. The results indicate that fossilization takes place in two stages: (i) an iron mineral is formed which differs according to the geological

N. A. Eissa; H. A. Sallam; B. A. Ashi; M. Y. Hassan; S. A. Saleh

1976-01-01

412

Characterization of permineralized kerogen from an Eocene fossil fern  

Microsoft Academic Search

The processes of organic maturation that occur during the permineralization of fossils and the detailed chemistry of the resulting products are incompletely understood. Primary among such processes is the geochemical alteration of biological matter to produce kerogen, such as that which comprises the cell walls of the fossils studied here: essentially unmetamorphosed, Eocene plant axes (specimens of the fossil fern

Andrew D. Czaja; Anatoliy B. Kudryavtsev; George D. Cody; J. William Schopf

2009-01-01

413

Fossil Feces (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

This article is a Why Files short piece about coprolites: fossilized animal feces. The article explains how fossilization occurs in feces and why coprolites are useful to scientists. Fossilized feces reveal a great deal about the eating habits of dinosaurs, as well as other extinct animals.

Tenenbaum, David

414

First Fossil Lamprey: A Record from the Pennsylvanian of Illinois  

Microsoft Academic Search

A fossil record of lampreys has previously been unknown. A new genus demonstrates the presence of this group in the Pennsylvanian. The body outline, parts of the head skeleton, rasping tongue mechanism, gill basket, and other internal organs are preserved. The fossils are very similar in structure to modern forms. The absence of hagfish characters in the fossil supports the

David Bardack; Rainer Zangerl

1968-01-01

415

Written in stone: fossils, genes and evo–devo  

Microsoft Academic Search

Fossils give evo–devo a past. They inform phylogenetic trees to show the direction of evolution of developmental features, and they can reveal ancient body plans. Fossils also provide the primary data that are used to date past events, including divergence times needed to estimate molecular clocks, which provide rates of developmental evolution. Fossils can set boundaries for hypotheses that are

Rudolf A. Raff

2007-01-01

416

Fossil Folklore from India: The Siwalik Hills and the Mahâbhârata  

Microsoft Academic Search

All over the world, from antiquity to the present, people have often explained fossil discoveries as proof of the historical truth of legends and myths, or used them as a basis for a new legend. Most often, large vertebrate fossils have been explained as bones and teeth of giant humans, dragons and monsters, saints and heroes. Smaller invertebrate fossils were

Alexandra van der Geer; Michael Dermitzakis; John de Vos

2008-01-01

417

Status of Fossil Energy Resources: A Global Perspective  

Microsoft Academic Search

This article deals with recently status of global fossil energy sources. Fossil energy sources have been split into three categories: oil, coal, and natural gas. Fossil fuels are highly efficient and cheap. Currently oil is the fastest primary energy source in the world (39% of world energy consumption). Coal will be a major source of energy for the world for

M. Balat

2007-01-01

418

METHODS TO REDUCE THE DEPENDENCE ON FOSSIL FUEL  

Microsoft Academic Search

SUMMARY The wealth level in the world is directly connected with energy use. Currently, fossil fuels provide the bulk of that energy. By definition, the availability of fossil fuel is finite. Moreover, there are strong indications that the CO2 emissions resulting from fossil fuel use have an effect on climates. Therefore, energy-efficient technologies and the use of sustainable energy should

Jacob Klimstra

419

Use of ground penetrating radar in detecting fossilized dinosaur bones  

Microsoft Academic Search

Ground penetrating radar (GPR) has been used successfully to help archaeologists locate building foundations and other artifacts of past civilizations. Yet, little has been done to help paleontologists in their search for fossilized remains. Fossilized and partially fossilized dinosaur bones are located in a sandstone outcrop at the Dinosaur Ridge Natural Landmark outside Morrison, Colorado. The bones are located within

Todd M. Meglich

2000-01-01

420

MOLECULAR CLOCK DIVERGENCE ESTIMATES AND THE FOSSIL RECORD OF CETARTIODACTYLA  

Microsoft Academic Search

Molecular clock estimates of divergence times for artiodactyls and whales vary widely in their agreement with the fossil record. Recent estimates indicate that the divergence of whales from artiodactyls occurred 60 Ma, a date which compares well with the first appearances of fossil whales around 53.5 Ma, and artiodactyls at 55 Ma. Other estimates imply significant gaps in the fossil

JESSICA M. THEODOR

2004-01-01

421

In situ growth and density-functional-theory study of polarity-dependent homo-epitaxial ZnO microwires  

SciTech Connect

Polarity-dependent homo-epitaxy on (0001)-Zn and (0001)-O surfaces of cleaved ZnO microwires was investigated by in situ growth in ESEMand DFT simulations. ZnO monomers adsorption, adatoms desorption and chemisorption were simulated to understand the explicit mechanism.

Zhu, Rui [ORNL; Xu, Jun [ORNL; Gao, Jingyun [Peking University; Zhang, Jingmin [Peking University; Zhu, Wenguang [University of Tennessee, Knoxville (UTK); Xu, Hongjun [Peking University; Sun, Yanghui [Peking University; Fu, Qiang [Peking University; Chen, Li [Peking University; Du, Dapeng [Peking University

2012-01-01

422

Molecular biology of Homo sapiens: Abstracts of papers presented at the 51st Cold Spring Harbor symposium on quantitative biology  

SciTech Connect

This volume contains abstracts of papers presented at the 51st Cold Springs Harbor Symposium on Quantitative Biology. The topic for this meeting was the ''Molecular Biology of Homo sapiens.'' Sessions were entitled Human Gene Map, Human Cancer Genes, Genetic Diagnosis, Human Evolution, Drugs Made Off Human Genes, Receptors, and Gene Therapy. (DT)

Watson, J.D.; Siniscalco, M.

1986-01-01

423

The expansion of grassland ecosystems in Africa in relation to mammalian evolution and the origin of the genus Homo  

Microsoft Academic Search

The relationship between climatic change and human evolution can be framed in terms of three major hypotheses. A modern version of the long-held savanna hypothesis posits that the expansion of grassland ecosystems in Africa was driven by global climatic change and led to the divergence of hominins from the apes and to the origin of the Homo clade. A related

Anna K. Behrensmeyer

2004-01-01

424

Both Homo and Heterodimers of Marek's Disease Virus Encoded Meq Protein Contribute to Transformation of Lymphocytes in Chickens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Marek’s disease virus (MDV) elicits T-cell lymphomas in chickens. The MDV genome encodes an oncoprotein, Meq, with similarity to the Jun/Fos family of proteins. Similar to Jun, the leucine zipper region of Meq allows the formation of homo- and heterodimers. We have previously shown that Meq homodime...

425

Iron\\/copper promoted oxidative homo-coupling reaction of terminal alkynes using air as the oxidant  

Microsoft Academic Search

An inexpensive catalytic system, which used a readily available Fe(acac)3 and trace quantity of Cu(acac)2 as the co-catalyst and air as the oxidant for the homo-coupling of terminal alkynes, has been developed. The catalytic system could also apply to the cross-coupling reaction of two different terminal alkynes.

Xu Meng; Chuanbin Li; Baochun Han; Tiansheng Wang; Baohua Chen

2010-01-01

426

Copying results and copying actions in the process of social learning: chimpanzees ( Pan troglodytes ) and human children ( Homo sapiens )  

Microsoft Academic Search

There is currently much debate about the nature of social learning in chimpanzees. The main question is whether they can copy others’ actions, as opposed to reproducing the environmental effects of these actions using their own preexisting behavioral strategies. In the current study, chimpanzees (Pan troglodytes) and human children (Homo sapiens) were shown different demonstrations of how to open a

Josep Call; Malinda Carpenter; Michael Tomasello

2005-01-01

427

A bivariate approach to the variation of the parietal curvature in the genus homo.  

PubMed

The parietal bones approximately cover the extension of the underlying parietal lobes. Although the boundaries of these two anatomical elements do not coincide, during morphogenesis the growth of the parietal bones is largely induced by the pressure exerted by the parietal lobes. Modern humans display larger parietal chords and arcs compared with non-modern human species. However, the variation of these variables have not been analyzed before according to the covariation with the general endocranial diameters. When the curvature of the parietal bones is regressed onto the main neurocranial distances, modern humans show larger relative values, suggesting not only an absolute enlargement but a definite allometric change. Taking into account the morphogenetic relationships with the parietal lobes, these results further support previous hypotheses suggesting a relative enlargement of these cortical areas in Homo sapiens, by using simple and reliable homologous neurocranial arcs. PMID:21809464

Bruner, Emiliano; De La Cuétara, José Manuel; Holloway, Ralph

2011-08-01

428

Synthesis and biological evaluation of a new series of highly functionalized 7'-homo-anhydrovinblastine derivatives.  

PubMed

Sixteen new 7'-homo-anhydrovinblastine derivatives were prepared in one or two steps from vinorelbine by means of an original and regiospecific rearrangement and subsequent diastereoselective reduction. This strategy has allowed fast access to a family of vinca alkaloid derivatives with an enlarged and functionalized ring C'. Their synthesis and biological evaluation are reported. One compound (compound 35) is 1.7 times more active than vinorelbine as a tubulin assembly inhibitor. Moreover, some of these compounds are highly cytotoxic, and two of them are more potent than vinorelbine on HCT116 and K562 cell lines. Molecular modeling studies, carried out with two of the new vinca derivatives, provide useful hints about how a given functionalization introduced at positions 7' and 8' of the C' ring results in improved binding interactions between one of the new derivatives and the interdimer interface when compared to the parent compound vinblastine. PMID:23822556

Gherbovet, Olga; Coderch, Claire; García Alvarez, María Concepción; Bignon, Jérôme; Thoret, Sylviane; Martin, Marie-Thèrese; Guéritte, Françoise; Gago, Federico; Roussi, Fanny

2013-07-18

429

Scanning tunneling microscopy of doping and compositional III-V homo- and heterostructures  

SciTech Connect

Scanning tunneling microscopy (STM) was used to study the (110) cross-sectional surfaces of molecular-beam epitaxially grown III-V homo- and heterostructures, which include GaAs multiple p-n junctions, (InGa)As/GaAs strained-layer multiple quantum wells, and (AlGa)As/GaAs heterojunctions. Both doping and compositional effects can be resolved by the topographic contrasts of constant-current STM images. The samples were prepared by either cleaving in ultrahigh vacuum or cleaving ex situ followed by sulfide [(NH{sub 4}){sub 2}S] passivation. Sulfide passivated samples have been found to be advantageous for the measurements of scanning tunneling spectroscopy. 20 refs., 5 figs.

Gwo, S.; Chao, K.J.; Smith, A.R. [Univ. of Texas, Austin, TX (United States)] [and others

1993-07-01

430

Dentofacial growth and development in Homo sapiens: evidence from perinatal individuals from Punic Carthage.  

PubMed

Study of perinatal individuals from 7-4th c. B.C. Punic Carthage and specimens from more recent sources elucidates: 1. variability in the formation of the infraorbital foramen; 2. the nature of, and variability in, the expression of the incisive suture. With regard to the latter, and in conjunction with data on the embryological formation of the upper jaw and dentition, the following generalization appears warranted in Homo sapiens. The incisors and canine may come to erupt in the alveolar bone associated with the premaxillary region. Combination of these data with those on the timing of tooth germ development and their forward migration yields an explanation of the dental anomalies associated with anterior facial cleft and a prediction of when this disorder occurs. PMID:6818874

Schwartz, J H

1982-01-01

431

Spectroscopic investigations, quantum chemical calculations, HOMO-LUMO and NBO/NLMO analysis of 4-pyridinecarbohydrazide  

NASA Astrophysics Data System (ADS)

The FT-IR and FT-Raman spectra of 4-pyridinecarbohydrazide have been recorded. The complete vibrational assignment and analysis of the fundamental modes was carried out using the experimental data and quantum chemical studies. The observed vibrational data were compared with the wavenumbers derived theoretically for the optimized geometry of the compound from the DFT-B3LYP gradient calculations employing 6-311++G(d,p) basis set. The 1H and 13C NMR chemical shifts have been simulated. Thermodynamic properties have been calculated at different temperatures. HOMO-LUMO energy gap has been calculated. The intramolecular contacts have been interpreted using Natural Bond Orbital (NBO) and Natural Localized Molecular Orbital (NLMO) analysis.

Gobinath, E.; John Xavier, R.

2013-11-01

432

Identification and Functional Impact of Homo-oligomers of the Human Proton-coupled Folate Transporter*  

PubMed Central

The proton-coupled folate transporter (PCFT; SLC46A1) is a proton-folate symporter that is abundantly expressed in solid tumors and normal tissues, such as duodenum. The acidic pH optimum for PCFT is relevant to intestinal absorption of folates and could afford a means of selectively targeting tumors with novel cytotoxic antifolates. PCFT is a member of the major facilitator superfamily of transporters. Because major facilitator superfamily members exist as homo-oligomers, we tested this for PCFT because such structures could be significant to PCFT mechanism and regulation. By transiently expressing PCFT in reduced folate carrier- and PCFT-null HeLa (R1-11) cells and chemical cross-linking with 1,1-methanediyl bismethanethiosulfonate and Western blotting, PCFT species with molecular masses approximating those of the PCFT dimer and higher order oligomers were detected. Blue native polyacrylamide gel electrophoresis identified PCFT dimer, trimer, and tetramer forms. PCFT monomers with hemagglutinin and His10 epitope tags were co-expressed in R1-11 cells, solubilized, and bound to nickel affinity columns, establishing their physical associations. Co-expressing YPet and ECFP*-tagged PCFT monomers enabled transport and fluorescence resonance energy transfer in plasma membranes of R1-11 cells. Combined wild-type (WT) and inactive mutant P425R PCFTs were targeted to the cell surface by surface biotinylation/Western blots and confocal microscopy and functionally exhibited a “dominant-positive” phenotype, implying positive cooperativity between PCFT monomers and functional rescue of mutant by WT PCFT. Our results demonstrate the existence of PCFT homo-oligomers and imply their functional and regulatory impact. Better understanding of these higher order PCFT structures may lead to therapeutic applications related to folate uptake in hereditary folate malabsorption, and delivery of PCFT-targeted chemotherapy drugs for cancer.

Hou, Zhanjun; Kugel Desmoulin, Sita; Etnyre, Erika; Olive, Mary; Hsiung, Benjamin; Cherian, Christina; Wloszczynski, Patrick A.; Moin, Kamiar; Matherly, Larry H.

2012-01-01

433

Designed aromatic homo-dipeptides: formation of ordered nanostructures and potential nanotechnological applications.  

PubMed

Molecular self-assembly offers new routes for the fabrication of novel materials at the nano-scale. Peptide-based nanostructures represent nano-objects of particular interest, as they are biocompatible, can be easily synthesized in large amounts, can be decorated with functional elements and can be used in various biological and non-biological applications. We had previously revealed the formation of highly ordered tubular structures by the diphenylalanine peptide, the core recognition motif of Alzheimer's beta-amyloid polypeptide, due to specific aromatic interactions. We further confirmed this model and demonstrated that a non-charged peptide analogue, Ac-Phe-Phe-NH2, self-assembled into similar tubular structures. We later explored other amine and carboxyl modified diphenylalanine peptide analogues and revealed that these dipeptides can form ordered tubular structures at the nanometric scale. Moreover, a very similar peptide, the diphenylglycine, self-assembled into ordered nano-spherical assemblies. Here we extend our research and explore the self-assembly of other homo-aromatic dipeptides in which their phenyl side-chains are modified with halogen atoms (di-para-fluoro-Phe, di-pentafluoro-Phe, di-para-iodo-Phe), additional phenyl groups (di-4-phenyl-Phe), or with nitro substitutions (di-para-nitro-Phe). We also probed the effect of the alteration of the phenyl groups with naphtyl groups (di-D-1-Nal and di-D-2-Nal). In all cases, well-ordered nanostructures were obtained and studied by scanning electron microscopy, transmission electron microscopy and vibrational spectroscopy. Taken together, the current work and previous ones define the homo-aromatic dipeptide as a central motif for the formation of ordered self-assembled tubular, spherical and two-dimensional structures at the nano-scale. PMID:16582461

Reches, Meital; Gazit, Ehud

2006-02-02

434

Bone remodeling of the Homo heidelbergensis mandible; the Atapuerca-SH sample.  

PubMed

Growth by bone remodeling is one of the key mechanisms responsible for skeletal morphology. This mechanism consists of the coordinated activity of two cellular groups: osteoblasts and osteoclasts, which are responsible for bone deposition and resorption, respectively. Information obtained from the study of these remodeling growth fields allows us to understand how species-specific craniofacial form is achieved. These data can help to explain the facial growth differences among Primates, both extinct and extant. The aim of this study was to obtain the distribution of growth remodeling fields of the Homo heidelbergensis mandible (Atapuerca-SH sample), and to infer the growth processes responsible for its specific morphology. A Reflected Light Microscope (RLM) was used to identify the microfeatures of the bone surface related to bone deposition and resorption. Results show that H. heidelbergensis presents a specific growth field distribution, which differs slightly between immature and adult individuals. Interpretation of these maps indicates that the mandible of H. heidelbergensis presents noteworthy variability in the symphyseal region. Two distinct patterns of growth are seen, one of those unique for this species and the other similar to that of Homo sapiens. The lingual side of the mandibular corpus has a resorption area found only in this species and one that includes a variable extension in immature and adult individuals. Finally, the mandibular ramus is characterized, among other aspects, by a large resorption field on its buccal surface. Considering the mandible as a whole, the bone remodeling pattern obtained in this work shows that lower facial growth in H. heidelbergensis is dominated mainly by forward growth, illustrated by the strong inward displacement of the ramus, which is in agreement with the Enlow's "V" growth principle. PMID:20042223

Rosas, Antonio; Martinez-Maza, Cayetana

2009-12-29

435

Fossilization of soft tissue in the laboratory.  

PubMed

Some of the most remarkable fossils preserve cellular details of soft tissues. In many of these, the tissues have been replaced by calcium phosphate. This process has been assumed to require elevated concentrations of phosphate in sediment pore waters. In decay experiments modern shrimps became partially mineralized in amorphous calcium phosphate, preserving cellular details of muscle tissue, particularly in a system closed to oxygen. The source for the formation of calcium phosphate was the shrimp itself. Mineralization, which was accompanied by a drop in pH, commenced within 2 weeks and increased in extent for at least 4 to 8 weeks. This mechanism halts the normal loss of detail of soft-tissue morphology before fossilization. Similar closed conditions would prevail where organisms are rapidly overgrown by microbial mats. PMID:17801278

Briggs, D E; Kear, A J

1993-03-01

436

Transitional fossils and the origin of turtles.  

PubMed

The origin of turtles is one of the most contentious issues in systematics with three currently viable hypotheses: turtles as the extant sister to (i) the crocodile-bird clade, (ii) the lizard-tuatara clade, or (iii) Diapsida (a clade composed of (i) and (ii)). We reanalysed a recent dataset that allied turtles with the lizard-tuatara clade and found that the inclusion of the stem turtle Proganochelys quenstedti and the 'parareptile' Eunotosaurus africanus results in a single overriding morphological signal, with turtles outside Diapsida. This result reflects the importance of transitional fossils when long branches separate crown clades, and highlights unexplored issues such as the role of topological congruence when using fossils to calibrate molecular clocks. PMID:20534602

Lyson, Tyler R; Bever, Gabe S; Bhullar, Bhart-Anjan S; Joyce, Walter G; Gauthier, Jacques A

2010-06-09

437

Structural coloration in a fossil feather  

PubMed Central

Investigation of feathers from the famous Middle Eocene Messel Oil Shale near Darmstadt, Germany shows that they are preserved as arrays of fossilized melanosomes, the surrounding beta-keratin having degraded. The majority of feathers are preserved as aligned rod-shaped eumelanosomes. In some, however, the barbules of the open pennaceous, distal portion of the feather vane are preserved as a continuous external layer of closely packed melanosomes enclosing loosely aligned melanosomes. This arrangement is similar to the single thin-film nanostructure that generates an iridescent, structurally coloured sheen on the surface of black feathers in many lineages of living birds. This is, to our knowledge, the first evidence of preservation of a colour-producing nanostructure in a fossil feather and confirms the potential for determining colour differences in ancient birds and other dinosaurs.

Vinther, Jakob; Briggs, Derek E. G.; Clarke, Julia; Mayr, Gerald; Prum, Richard O.

2010-01-01

438

Structural coloration in a fossil feather.  

PubMed

Investigation of feathers from the famous Middle Eocene Messel Oil Shale near Darmstadt, Germany shows that they are preserved as arrays of fossilized melanosomes, the surrounding beta-keratin having degraded. The majority of feathers are preserved as aligned rod-shaped eumelanosomes. In some, however, the barbules of the open pennaceous, distal portion of the feather vane are preserved as a continuous external layer of closely packed melanosomes enclosing loosely aligned melanosomes. This arrangement is similar to the single thin-film nanostructure that generates an iridescent, structurally coloured sheen on the surface of black feathers in many lineages of living birds. This is, to our knowledge, the first evidence of preservation of a colour-producing nanostructure in a fossil feather and confirms the potential for determining colour differences in ancient birds and other dinosaurs. PMID:19710052

Vinther, Jakob; Briggs, Derek E G; Clarke, Julia; Mayr, Gerald; Prum, Richard O

2009-08-26

439

Determining Age of Rocks and Fossils  

NSDL National Science Digital Library

This activity will help students to have a better understanding of the basic principles used to determine the age of rocks and fossils. It consists of several parts: to have students determine relative age of a geologically complex area, to familiarize students with the concept of half-life in radioactive decay, to have students see that individual runs of statistical processes are less predictable than the average of many runs, and to demonstrate how the rate of radioactive decay and the buildup of the resulting decay product is used in radiometric dating of rocks. Students learn to use the principles of determining relative age to show how ages of rocks and fossils can be narrowed even if they cannot be dated radiometrically.

Mckinney, Frank

440

FOSSIL RIDGE WILDERNESS STUDY AREA, COLORADO.  

USGS Publications Warehouse

The Fossil Ridge Wilderness Study Area, approximately 20 mi northeast of Gunnison in central Colorado, was studied and its mineral-resource potential assessed. Portions of the study area have substantiated resource potential for gold, silver, copper, lead, zinc, molybdenum, uranium, thorium, rare-earth elements, and high-calcium limestone. Much of the area has a probable resource potential for the preceeding commodities as well as for tin. Various other elements are found in anomalous concentrations within the study area, but there is likelihood for their occurrence in amounts sufficient to constitute resources. Exploration, especially for molybdenum, gold, and uranium, has been active in the past and is expected to continue in the future. No potential for fossil fuel resources was identified in this study.

DeWitt, Ed; Kluender, Steven, E.

1984-01-01

441

Fossil figure contribution to the lunar figure  

NASA Astrophysics Data System (ADS)

The unusual shape of the Moon given its present rotational and orbital state has been explained as due to a fossil figure preserving a record of remnant rotational and tidal deformation (Jeffreys, H. [1915]. Mem. R. Astron. Soc. 60, 187-217; Lambeck, K., Pullan, S. [1980]. Phys. Earth Planet. Interiors 22, 29-35; Garrick-Bethell, I., Wisdom, J., Zuber, M.T. [2006]. Science 313, 652-655). However, previous studies assume infinite rigidity and ignore deformation due to changes in the rotational and orbital potentials as the Moon evolves to the present state. We interpret the global lunar figure with a physical model that takes into account this deformation. Although the Moon deforms in response to rotational and orbital changes, a fossil figure capable of explaining the observed figure can be preserved by an elastic lithosphere.

Matsuyama, Isamu

2013-01-01

442

Fossil energy waste management. Technology status report  

SciTech Connect

This report describes the current status and recent accomplishments of the Fossil Energy Waste Management (FE WM) projects sponsored by the Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE). The primary goal of the Waste Management Program is to identify and develop optimal strategies to manage solid by-products from advanced coal technologies for the purpose of ensuring the competitiveness of advanced coal technologies as a future energy source. The projects in the Fossil Energy Waste Management Program are divided into three types of activities: Waste Characterization, Disposal Technologies, and Utilization Technologies. This technology status report includes a discussion on barriers to increased use of coal by-products. Also, the major technical and nontechnical challenges currently being addressed by the FE WM program are discussed. A bibliography of 96 citations and a list of project contacts is included if the reader is interested in obtaining additional information about the FE WM program.

Bossart, S.J.; Newman, D.A.

1995-02-01

443

Fossil Jets from Black Hole Transients  

NASA Astrophysics Data System (ADS)

Observations of the fossil X-ray jet from the black hole transient 4U 1755-33 enabled us to detect the flux decay of the southern jet, identify the X-ray emission mechanism as synchrotron radiation, and place constraints on the energetics of the jet. We propose for a third observation with the goals of detecting decay in the northern jet, more accurately measuring the southern jet decay, and searching for motions within the jet. Detection of decay of the northern jet at a rate similar to the southern jet would imply that the kinetic power of the jet was comparable to the X-ray luminosity while the source was active. We also propose observations of two additional sources likely to exhibit fossil X-ray jets.

Kaaret, Philip

2006-10-01

444

Precambrian ``fossil'' Vermiforma is a tectograph  

SciTech Connect

Vermiforma antiqua Cloud 1976, once celebrated as the earliest animal fossil of the US, is actually a tectonic artifact. The main argument is that the congruence and equal orientation of multiple patterns on the same bedding plane are incompatible with swaying worm bodies of worm burrows. As shown by analog and numerical simulations, these structures can be explained as tracks of particles that broke out from the base of an overlying turbidite and became rolled between beds during bed-to-bed shearing.

Seilacher, A.; Meschede, M.; Bolton, E.W.; Luginsland, H.

2000-03-01

445

Predation on Recent and Fossil Echinoids  

Microsoft Academic Search

\\u000a Predator-prey interactions in marine ecosystems are documented in the fossil record by drill holes, repair scars, tooth marks\\u000a and other structural damage left by durophagous (“hard-eating”) predators on skeletons of their prey. Previous paleoecological\\u000a research focused primarily on benthic mollusks (e.g., Vermeij, 1977, 1983, 1987; Vermeij et al., 1980, 1981; Kitchell et al. 1981; Kitchell, 1986; Kelley and Hansen, 1993;

Micha? Kowalewski; James H. Nebelsick

446

Fossil plants: Integrating new technology and design  

Microsoft Academic Search

In a power generation market characterized by increasing competition, utilities need to effectively apply cost-beneficial advances in fossil plant technology and design that have come out of research sponsored by EPRI and other organizations around the world. To support utilities in this effort, EPRI is developing a powerful computer-based information resource consisting of an easy-to-use design and analysis workstation and

Pace

1992-01-01

447

Fossil energy review, January--March 1991  

SciTech Connect

This publication consists of a quarterly update of key events in the Department of Energy's Fossil Energy program, published for business, industry and academic researchers. This issue presents articles on the following topics: clean coal technology program; drawdown of the strategic petroleum reserve, a new coal preparation plant; a scrubbing operation for cement kiln pollution control; use of slurry diagnostics in artificial heart studies; and the trans--Alaska pipeline system. (CBS)

Not Available

1991-01-01

448

The fossil pollen record of Araceae  

Microsoft Academic Search

The fossil record of Araceae pollen beginning in the late Early Cretaceous and peaking in the Paleocene\\/Eocene is very sparse\\u000a up to now, consisting of three highly distinctive types: zona-aperturate pollen of the Monstera or Gonatopus type (very similar to Proxapertites operculatus), an ulcerate-spiny type typical for Limnobiophyllum, and a polyplicate, omniaperturate pollen type (an ephedroid pollen with non-gnetalean affinities)

M. Hesse; R. Zetter

2007-01-01

449

Global energy resources. [Review, emphasizing fossil fuels  

Microsoft Academic Search

We are in the somewhat paradoxical situation of having more confidence in the extent of our long- or very long-term energy resources than in our mid-term supply. This is why fossil-energy resources are emphasized in this article; we must rely on them for at least 80 to 90% of our energy supply until the end of the century (as far

Grenon

1977-01-01

450

Atomic force microscopy of Precambrian microscopic fossils  

Microsoft Academic Search

Atomic force microscopy (AFM) is a technique used routinely in material science to image substances at a submicron (including nm) scale. We apply this technique to analysis of the fine structure of organic-walled Precambrian fossils, microscopic sphaeromorph acritarchs (cysts of planktonic unicellular protists) permineralized in 650-million-year-old cherts of the Chichkan Formation of southern Kazakhstan. AFM images, backed by laser-Raman spectroscopic

André Kempe; J. William Schopf; Wladyslaw Altermann; Anatoliy B. Kudryavtsev; Wolfgang M. Heckl

2002-01-01

451

Implications of natural selection in shaping 99.4% nonsynonymous DNA identity between humans and chimpanzees: Enlarging genus Homo  

PubMed Central

What do functionally important DNA sites, those scrutinized and shaped by natural selection, tell us about the place of humans in evolution? Here we compare ?90 kb of coding DNA nucleotide sequence from 97 human genes to their sequenced chimpanzee counterparts and to available sequenced gorilla, orangutan, and Old World monkey counterparts, and, on a more limited basis, to mouse. The nonsynonymous changes (functionally important), like synonymous changes (functionally much less important), show chimpanzees and humans to be most closely related, sharing 99.4% identity at nonsynonymous sites and 98.4% at synonymous sites. On a time scale, the coding DNA divergencies separate the human–chimpanzee clade from the gorilla clade at between 6 and 7 million years ago and place the most recent common ancestor of humans and chimpanzees at between 5 and 6 million years ago. The evolutionary rate of coding DNA in the catarrhine clade (Old World monkey and ape, including human) is much slower than in the lineage to mouse. Among the genes examined, 30 show evidence of positive selection during descent of catarrhines. Nonsynonymous substitutions by themselves, in this subset of positively selected genes, group humans and chimpanzees closest to each other and have chimpanzees diverge about as much from the common human–chimpanzee ancestor as humans do. This functional DNA evidence supports two previously offered taxonomic proposals: family Hominidae should include all extant apes; and genus Homo should include three extant species and two subgenera, Homo (Homo) sapiens (humankind), Homo (Pan) troglodytes (common chimpanzee), and Homo (Pan) paniscus (bonobo chimpanzee).

Wildman, Derek E.; Uddin, Monica; Liu, Guozhen; Grossman, Lawrence I.; Goodman, Morris

2003-01-01

452

The current state of korean paleoanthropology.  

PubMed

The hominid fossil and Paleolithic archaeology records from the Korean Peninsula are extensive, but relatively little is known about the Korean human evolutionary record outside this region. The Korean paleoanthropological record is reviewed here in light of major research issues, including the hominid fossil record, relative and chronometric dating, lithic analysis, hominid subsistence, and the presence of bone tools, art and symbolism. Some of the major conclusions drawn from this review include: (1) hominid fossils have been found in nine separate sites on the Korean Peninsula; (2) possible Homo erectus fossils are present in North Korea; (3) Ryonggok Cave, in North Korea, has exposed the remains of at least five archaic Homo sapiens individuals; (4) a possible burial of an anatomically modern Homo sapiens child, discovered in Hungsu Cave in South Korea, has been tentatively dated to roughly 40,000 years ago; (5) handaxes and cleavers have been found at a number of sites near Chongokni and they appear to date to at least 100,000 years ago; and (6) taphonomic studies are necessary for addressing issues related to determining the nature of hominid-carnivore interaction over similar resources (e.g. carcasses and shelter); and the presence/absence of Early Paleolithic bone tools, art, and symbolism in Korea. PMID:10835263

Norton, C J

2000-06-01

453

Tool making, hand morphology and fossil hominins.  

PubMed

Was stone tool making a factor in the evolution of human hand morphology? Is it possible to find evidence in fossil hominin hands for this capability? These questions are being addressed with increasingly sophisticated studies that are testing two hypotheses; (i) that humans have unique patterns of grip and hand movement capabilities compatible with effective stone tool making and use of the tools and, if this is the case, (ii) that there exist unique patterns of morphology in human hands that are consistent with these capabilities. Comparative analyses of human stone tool behaviours and chimpanzee feeding behaviours have revealed a distinctive set of forceful pinch grips by humans that are effective in the control of stones by one hand during manufacture and use of the tools. Comparative dissections, kinematic analyses and biomechanical studies indicate that humans do have a unique pattern of muscle architecture and joint surface form and functions consistent with the derived capabilities. A major remaining challenge is to identify skeletal features that reflect the full morphological pattern, and therefore may serve as clues to fossil hominin manipulative capabilities. Hominin fossils are evaluated for evidence of patterns of derived human grip and stress-accommodation features. PMID:24101624

Marzke, Mary W

2013-10-07

454

Stellar Populations of Fossil Group Galaxies  

NASA Astrophysics Data System (ADS)

Fossil groups are thought to be the remnants of groups of galaxies in which all the component galaxies have merged. Left behind is one, large, elliptical galaxy (sometimes surrounded by faint remnants of the group), which has a mass and X-ray luminosity comparable to an entire group of galaxies. It is thought that these objects are the end state of evolution for a galaxy group and have not undergone a major merger in the past 1 Gyr. This makes them ideal for studying characteristics intrinsic to the group environment. We studied a sample of seven candidate fossil groups, selected from Santos et al. 2007, using the SparsePak Integral Field Unit and Bench Spectrograph on the WIYN 3.5m telescope (Kitt Peak, AZ). Here, we present the results of our spectroscopic survey. We correlated our data with multi-wavelength observations of these galaxies, including the Hess et al. (2010) radio continuum observations, and found evidence of AGN activity. To better understand if the AGN is correlated with the star formation history of the fossil group, we used our spectroscopic data and data from SDSS to investigate the stellar populations of the central elliptical galaxies. Fitting these data with a stellar population synthesis model, we find that the star formation history of these galaxies is broadly consistent with the theory that these galaxy groups formed through minor mergers. This research was supported by the NSF/REU grant AST-1004881 and the University of Wisconsin-Madison.

Pequette, Naomi; Alexander, K.; Wilcots, E. M.

2011-01-01

455

Fossil avian eggshell preserves ancient DNA  

PubMed Central

Owing to exceptional biomolecule preservation, fossil avian eggshell has been used extensively in geochronology and palaeodietary studies. Here, we show, to our knowledge, for the first time that fossil eggshell is a previously unrecognized source of ancient DNA (aDNA). We describe the successful isolation and amplification of DNA from fossil eggshell up to 19 ka old. aDNA was successfully characterized from eggshell obtained from New Zealand (extinct moa and ducks), Madagascar (extinct elephant birds) and Australia (emu and owl). Our data demonstrate excellent preservation of the nucleic acids, evidenced by retrieval of both mitochondrial and nuclear DNA from many of the samples. Using confocal microscopy and quantitative PCR, this study critically evaluates approaches to maximize DNA recovery from powdered eggshell. Our quantitative PCR experiments also demonstrate that moa eggshell has approximately 125 times lower bacterial load than bone, making it a highly suitable substrate for high-throughput sequencing approaches. Importantly, the preservation of DNA in Pleistocene eggshell from Australia and Holocene deposits from Madagascar indicates that eggshell is an excellent substrate for the long-term preservation of DNA in warmer climates. The successful recovery of DNA from this substrate has implications in a number of scientific disciplines; most notably archaeology and palaeontology, where genotypes and/or DNA-based species identifications can add significantly to our understanding of diets, environments, past biodiversity and evolutionary processes.

Oskam, Charlotte L.; Haile, James; McLay, Emma; Rigby, Paul; Allentoft, Morten E.; Olsen, Maia E.; Bengtsson, Camilla; Miller, Gifford H.; Schwenninger, Jean-Luc; Jacomb, Chris; Walter, Richard; Baynes, Alexander; Dortch, Joe; Parker-Pearson, Michael; Gilbert, M. Thomas P.; Holdaway, Richard N.; Willerslev, Eske; Bunce, Michael

2010-01-01

456

Traversing the mountaintop: world fossil fuel production to 2050  

PubMed Central

During the past century, fossil fuels—petroleum liquids, natural gas and coal—were the dominant source of world energy production. From 1950 to 2005, fossil fuels provided 85–93% of all energy production. All fossil fuels grew substantially during this period, their combined growth exceeding the increase in world population. This growth, however, was irregular, providing for rapidly growing per capita production from 1950 to 1980, stable per capita production from 1980 to 2000 and rising per capita production again after 2000. During the past half century, growth in fossil fuel production was essentially limited by energy demand. During the next half century, fossil fuel production will be limited primarily by the amount and characteristics of remaining fossil fuel resources. Three possible scenarios—low, medium and high—are developed for the production of each of the fossil fuels to 2050. These scenarios differ primarily by the amount of ultimate resources estimated for each fossil fuel. Total fossil fuel production will continue to grow, but only slowly for the next 15–30 years. The subsequent peak plateau will last for 10–15 years. These production peaks are robust; none of the fossil fuels, even with highly optimistic resource estimates, is projected to keep growing beyond 2050. World fossil fuel production per capita will thus begin an irreversible decline between 2020 and 2030.

Nehring, Richard

2009-01-01

457

Hawaii energy strategy project 2: Fossil energy review. Task 1: World and regional fossil energy dynamics  

SciTech Connect

This report in the Hawaii Energy Strategy Project examines world and regional fossil energy dynamics. The topics of the report include fossil energy characteristics, the world oil industry including reserves, production, consumption, exporters, importers, refining, products and their uses, history and trends in the global oil market and the Asia-Pacific market; world gas industry including reserves, production, consumption, exporters, importers, processing, gas-based products, international gas market and the emerging Asia-Pacific gas market; the world coal industry including reserves, classification and quality, utilization, transportation, pricing, world coal market, Asia-Pacific coal outlook, trends in Europe and the Americas; and environmental trends affecting fossil fuels. 132 figs., 46 tabs.

Breazeale, K. [ed.; Isaak, D.T.; Yamaguchi, N.; Fridley, D.; Johnson, C.; Long, S.

1993-12-01

458

Calcaneus length determines running economy: Implications for endurance running performance in modern humans and Neandertals  

Microsoft Academic Search

The endurance running (ER) hypothesis suggests that distance running played an important role in the evolution of the genus Homo. Most researchers have focused on ER performance in modern humans, or on reconstructing ER performance in Homo erectus, however, few studies have examined ER capabilities in other members of the genus Homo. Here, we examine skeletal correlates of ER performance

David A. Raichlen; Hunter Armstrong; Daniel E. Lieberman

2011-01-01

459

Abstracts: Eighth Annual Conference on Fossil Energy Materials. Fossil Energy Program  

SciTech Connect

Abstracts are presented for about 40 papers. The Fossil Energy Advanced Research and Technology Development Materials program is an integrated materials research activity of the fossil energy coal program, whose objective is to conduct R and D for all advanced coal conversion and utilization technologies. The program is aimed at understanding materials behavior in coal system environments and the development of new materials for improving plant operations and reliability. A generic approach is used for addressing multiple coal technologies; for example, the hot-gas particulate filter development is applicable to pressurized fluidized bed combustion, integrated coal gasification combined-cycle, coal combustion, and indirectly fired combined-cycle systems.

Not Available

1994-07-01

460

Early stone technology on Flores and its implications for Homo floresiensis  

Microsoft Academic Search

In the Soa Basin of central Flores, eastern Indonesia, stratified archaeological sites, including Mata Menge, Boa Lesa and Kobatuwa (Fig. 1), contain stone artefacts associated with the fossilized remains of Stegodon florensis, Komodo dragon, rat and various other taxa. These sites have been dated to 840-700kyrBP (thousand years before present). The authenticity of the Soa Basin artefacts and their provenance

Adam Brumm; Fachroel Aziz; Gert D. van den Bergh; Michael J. Morwood; Mark W. Moore; Iwan Kurniawan; Douglas R. Hobbs; Richard Fullagar

2006-01-01