scholarly journals Endostructural assessment of a hominin maxillary molar (StW 669) from Milner Hall, Sterkfontein, South Africa

2019 ◽  
Vol 115 (9/10) ◽  
Author(s):  
Bontle Mataboge ◽  
Amélie Beaudet ◽  
Jason L. Heaton ◽  
Travis R. Pickering ◽  
Dominic Stratford
Keyword(s):  
South Africa ◽  
Homo Sapiens ◽  
Thickness Distribution ◽  
Three Dimensional ◽  
Homo Erectus ◽  
Dental Tissue ◽  
Enamel Thickness ◽  
Homo Neanderthalensis ◽  
Morphometric Analyses ◽  
Maxillary Molar

The site of the Sterkfontein Caves, South Africa, is one of the richest early hominin fossil-bearing sites in Africa. Recent excavations in the Milner Hall locality have contributed to the discovery of new hominin specimens, including StW 669, a right permanent maxillary first molar (M1). StW 669 was excavated from the T1 deposits, which consist of a mixture of sediments from Members 2 and 5 of the Sterkfontein Formation. Accordingly, the deposits have the potential to contain remains of Australopithecus, Paranthropus and Homo. In this study, we employed micro-focus X-ray tomography in order to assess dental tissue proportions, enamel thickness distribution and enamel-dentine junction morphology as approaches to investigate the taxonomy of StW 669. We compare our results to those generated on the teeth of Australopithecus africanus, Paranthropus robustus, Homo erectus, Homo antecessor, Homo neanderthalensis and Homo sapiens. Our results suggest that StW 669 shares quantitative and qualitative affinities with M1s of Homo in terms of tissue proportions (i.e. two- and three-dimensional average and relative enamel thickness of 1.2–1.3 mm and 18.4, respectively) and enamel thickness distribution (i.e. thickest enamel on the lingual aspect of the protocone). However, data on the enamel-dentine junction morphology of StW 669 are inconclusive as to the tooth’s taxonomic affinities. Pending additional morphometric analyses, our studies of inner morphology of the crown of StW 669 support its attribution to Homo.

scholarly journals Dental tissue proportions in fossil orangutans from mainland Asia and Indonesia

2011 ◽  
Vol 1 (1) ◽  
pp. e1 ◽  
Author(s):  
Tanya M. Smith ◽  
Anne-Marie Bacon ◽  
Fabrice Demeter ◽  
Ottmar Kullmer ◽  
Kim Thuy Nguyen ◽  
...  
Keyword(s):  
Fossil Record ◽  
Homo Sapiens ◽  
Homo Erectus ◽  
Dental Tissue ◽  
Developmental Constraints ◽  
Enamel Thickness ◽  
Selective Pressures ◽  
The Past ◽  
Geometric Scaling ◽  
Dental Reduction

Orangutans (Pongo) are the only great ape genus with a substantial Pleistocene and Holocene fossil record, demonstrating a much larger geographic range than extant populations. In addition to having an extensive fossil record, Pongo shows several convergent morphological similarities with Homo, including a trend of dental reduction during the past million years. While studies have documented variation in dental tissue proportions among species of Homo, little is known about variation in enamel thickness within fossil orangutans. Here we assess dental tissue proportions, including conventional enamel thickness indices, in a large sample of fossil orangutan postcanine teeth from mainland Asia and Indonesia. We find few differences between regions, except for significantly lower average enamel thickness (AET) values in Indonesian mandibular first molars. Differences between fossil and extant orangutans are more marked, with fossil Pongo showing higher AET in most postcanine teeth. These differences are significant for maxillary and mandibular first molars. Fossil orangutans show higher AET than extant Pongo due to greater enamel cap areas, which exceed increases in enamel-dentine junction length (due to geometric scaling of areas and lengths for the AET index calculation). We also find greater dentine areas in fossil orangutans, but relative enamel thickness indices do not differ between fossil and extant taxa. When changes in dental tissue proportions between fossil and extant orangutans are compared with fossil and recent Homo sapiens, Pongo appears to show isometric reduction in enamel and dentine, while crown reduction in H. sapiens appears to be due to preferential loss of dentine. Disparate selective pressures or developmental constraints may underlie these patterns. Finally, the finding of moderately thick molar enamel in fossil orangutans may represent an additional convergent dental similarity with Homo erectus, complicating attempts to distinguish these taxa in mixed Asian faunas. 

scholarly journals Arguments that Prehistorical and Modern Humans Belong to the Same Species

2019 ◽  
Author(s):  
Rainer Kühne
Keyword(s):  
Homo Sapiens ◽  
Single Species ◽  
Homo Erectus ◽  
Modern Humans ◽  
Homo Neanderthalensis ◽  
Out Of Africa

I argue that the evidence of the Out-of-Africa hypothesis and the evidence of multiregional evolution of prehistorical humans can be understood if there has been interbreeding between Homo erectus, Homo neanderthalensis, and Homo sapiens at least during the preceding 700,000 years. These interbreedings require descendants who are capable of reproduction and therefore parents who belong to the same species. I suggest that a number of prehistorical humans who are at present regarded as belonging to different species belong in fact to one single species.  

Birth and Death of the Holocene

2012 ◽  
Author(s):  
Jan Zalasiewicz ◽  
Mark Williams
Keyword(s):  
Homo Sapiens ◽  
Homo Erectus ◽  
Quaternary Period ◽  
Climate Oscillations ◽  
The Holocene ◽  
Homo Neanderthalensis ◽  
Droughts And Floods ◽  
Major Shift ◽  
Place Of Origin ◽  
The Many

It is just the latest of many climate phases of the Quaternary Period. The 103rd major shift in climate-driven global oxygen isotope values, to be precise, since the official-designated beginning of the Quaternary Period, 2.58 million years ago. And, many of those major phases, as we have seen, include dozens of climate oscillations far greater in scale than humans have witnessed since written records began. Nevertheless, it is our warm phase, that within which our civilization has grown, and hence it has been separated as a distinct epoch, the Holocene, a little over 0.01 of a million years long. Its counterpart is the Pleistocene Epoch, in which reside those other 2.57 million years of Quaternary time, and those other 102 major climate oscillations. Thus, we live—at least as far as formal geological nomenclature goes—in a privileged time. When this epoch began, Homo sapiens had already existed for some 150,000 years. As a species its prospects might not have seemed bright: this creature lacked anything terribly impressive in the way of claws or teeth or thick fur or armour. But by being ingenious at developing what one might describe as artificial claws and teeth—axes and spears and arrows—it could kill and eat mammals considerably larger than itself. In those early days, it might not have prospered, exactly, but it clung to existence, seemingly weathering at least one very bad patch, several tens of thousands of years ago, when its numbers dropped almost to extinction levels. It survived the climate oscillations of the late Pleistocene—the droughts and floods and episodes of bitter cold and killing heat—by adapting its behaviour or migrating as best it could. Its migrations from its place of origin, Africa, were on an epic scale. The many thousands of individual and collective stories of hope, fear, endurance, courage, tragedy, and (less commonly) triumph are all lost. What remains is the evidence that humans, by the beginning of the Holocene, had spread widely over Europe and Asia, ousting (it seems) their kindred hominin species, Homo neanderthalensis and Homo erectus.

scholarly journals The challenge of the abstract mind: symbols, signs and notational systems in European prehistory

2005 ◽  
Vol 32 ◽  
pp. 221-232 ◽  
Author(s):  
Harald Haarmann
Keyword(s):  
Homo Sapiens ◽  
Homo Erectus ◽  
Main Theme ◽  
Writing System ◽  
Southeastern Europe ◽  
Modern Humans ◽  
Symbiotic Interaction ◽  
Homo Neanderthalensis ◽  
Cave Paintings ◽  
Naturalistic Pictures

Since the earliest manifestations of symbolic activity in modern humans (Homo sapiens sapiens) in the Upper Palaeolithic, there is evidence for two independent cognitive procedures, for the production of representational images (naturalistic pictures or sculptures) and of abstract signs. The use of signs and symbols is attested for archaic humans (Homo neanderthalensis) and for Homo erectus while art in naturalistic style is an innovation among modern humans. The symbiotic interaction of the two symbolic capacities is illustrated for the visual heritage of Palaeolithic cave paintings in Southwestern Europe, for rock engravings in the Italian Alps (Val Camonica) and for the vivid use of signs and symbols in Southeastern Europe during the Neolithic. Around 5500 BC, sign use in Southeastern Europe reached a sophisticated stage of organization as to produce the earliest writing system of mankind. Since abstractness is the main theme in the visual heritage of the region, this script, not surprisingly, is composed of predominantly abstract signs.

scholarly journals Muscles of Facial Expression in Extinct Species of the Genus Homo

2016 ◽  
Author(s):  
Arturo Tozzi
Keyword(s):  
Facial Expression ◽  
General Trend ◽  
Homo Sapiens ◽  
Anatomical Variation ◽  
Homo Erectus ◽  
Human Species ◽  
Homo Neanderthalensis ◽  
Genus Homo ◽  
Levator Labii Superioris ◽  
Mimetic Muscles

ABSTRACTWe display a detailed description of mimetic muscles in extinct human species, framed in comparative and phylogenetic contexts. Using known facial landmarks, we assessed the arrangement of muscles of facial expression in Homo sapiens, neanderthalensis, erectus, heidelbergensis and ergaster. In modern humans, several perioral muscles are proportionally smaller in size (levator labii superioris, zygomaticus minor, zygomaticus major and triangularis) and/or located more medially (levator labii superioris, zygomaticus minor and quadratus labii inferioris) than in other human species. As mimetic musculature is examined in the most ancient specimens up to the most recent, there is a general trend towards an increase in size of corrugator supercillii and triangularis. Homo ergaster’s mimetic musculature closely resembles modern Homo, both in size and in location; furthermore, Homo erectus and Homo neanderthalensis share many muscular features. The extinct human species had an elaborate and highly graded facial communication system, but it remained qualitatively different from that reported in modern Homo. Compared with other human species, Homo sapiens clearly exhibits a lower degree of facial expression, possibly correlated with more sophisticated social behaviours and with enhanced speech capabilities. The presence of anatomical variation among species of the genus Homo raises important questions about the possible taxonomic value of mimetic muscles.

scholarly journals A hominin first rib discovered at the Sterkfontein Caves, South Africa

2016 ◽  
Vol Volume 112 (Number 5/6) ◽  
Author(s):  
Gaokgatlhee Tawan ◽  
Daniel García-Martínez ◽  
Jennifer Eyre ◽  
Markus Bastir ◽  
Lee Berger ◽  
...  
Keyword(s):  
South Africa ◽  
South African ◽  
Fossil Record ◽  
Three Dimensional ◽  
Great Apes ◽  
Small Individual ◽  
Geometric Morphometric ◽  
First Rib ◽  
Morphometric Analyses ◽  
Fossil Hominin

Abstract First ribs – the first or most superior ribs in the thorax – are rare in the hominin fossil record, and when found, have the potential to provide information regarding the upper thorax shape of extinct hominins. Here, we describe a partial first rib from Member 4 of the Sterkfontein Caves, South Africa. The rib shaft is broken away, so only the head and neck are preserved. The rib is small, falling closest to small-bodied Australopithecus first ribs (AL 288-1 and MH1). Given that it was recovered near the StW 318 femur excavation, which also represents a small individual, we suggest that the two may be associated. Three-dimensional geometric morphometric analyses were used to quantify the rib fragment morphology and compare it to extant hominoid and other fossil hominin ribs. While only the proximal end is preserved, our analyses show that South African Australopithecus share derived features of the proximal first rib more closely resembling A. afarensis and later hominins than great apes.

scholarly journals Reconstructing cranial evolution in an extinct hominin

2021 ◽  
Vol 288 (1943) ◽  
pp. 20202604
Author(s):  
Karen L. Baab
Keyword(s):  
Homo Sapiens ◽  
Three Dimensional ◽  
Homo Erectus ◽  
Population History ◽  
Middle Pleistocene ◽  
Group Variation ◽  
Dimensional Shape ◽  
History Narratives ◽  
Three Dimensional Shape ◽  
Shape Data

Homo erectus is the first hominin species with a truly cosmopolitan distribution and resembles recent humans in its broad spatial distribution. The microevolutionary events associated with dispersal and local adaptation may have produced similar population structure in both species. Understanding the evolutionary population dynamics of H. erectus has larger implications for the emergence of later Homo lineages in the Middle Pleistocene. Quantitative genetics models provide a means of interrogating aspects of long-standing H. erectus population history narratives. For the current study, cranial fossils were sorted into six major palaeodemes from sites across Africa and Asia spanning 1.8–0.1 Ma. Three-dimensional shape data from the occipital and frontal bones were used to compare intraspecific variation and test evolutionary hypotheses. Results indicate that H. erectus had higher individual and group variation than Homo sapiens , probably reflecting different levels of genetic diversity and population history in these spatially disperse species. This study also revealed distinct evolutionary histories for frontal and occipital bone shape in H. erectus , with a larger role for natural selection in the former. One scenario consistent with these findings is climate-driven facial adaptation in H. erectus , which is reflected in the frontal bone through integration with the orbits.

Evolution of Cranial and Endocranial Profiles inHomoSpecies: a Study in 2D Geometric Morphometrics

2016 ◽  
Vol 28 (3-4) ◽  
pp. 118-131
Author(s):  
L. Albessard ◽  
D. Grimaud-Hervé ◽  
A. Balzeau
Keyword(s):  
Geometric Morphometrics ◽  
Homo Sapiens ◽  
Brain Structures ◽  
Homo Erectus ◽  
Human Cognition ◽  
Cranial Bone ◽  
Cranial Morphology ◽  
Anatomical Features ◽  
Homo Neanderthalensis ◽  
Object Of Study

Cranial anatomical features play a prominent part in the definition of extinctHomotaxa and in species identification in fossils. Thus, knowledge of cranial morphology considered within its geochronological framework is essential to the understanding of the evolution, chronology, and dispersal of the genusHomo. The brain is also a valuable object of study for research on human evolution, because of features such as its large size and a high encephalization quotient in someHomospecies, as well as the complexity of human cognition. However, the joint evolution of endo- and ectocranial anatomies is still little studied, and landmarks representing cerebral anatomy rather than inner cranial bone anatomy are still rarely used. This exploratory piece of research examines endo- and ectocranial profiles in samples representing 3Homotaxa:Homo sapiens(fossil and recent specimens),Homo erectus, andHomo neanderthalensis. We used 2D geometric morphometrics to analyze the shape of the endo- and ectocranial vaults, as well as the relationships between selected anatomical features such as the extension of lobes and bones. The shapes of the vaults were computed using both fixed landmarks and sliding semi-landmarks. The fixed landmarks used for the endocranium were chosen in order to represent cerebral anatomy, in that they are defined by the imprints left by brain structures on the inner bone surface of the skull, and not by bony structures such as the inferior side of cranial sutures. Among other results, we have shown or confirmed specific features in the shape of the endocranium inHomo sapiens, as well as a few differences in the patterns of interplay between lobes and bones. These data, and any further results obtained with larger samples, may provide new insights into the development of the endocranial anatomical pattern inHomo sapiensand of its variability.

scholarly journals Arguments that Prehistorical and Modern Humans Belong to the Same Species

2019 ◽  
Author(s):  
Rainer Walter Kühne
Keyword(s):  
Homo Sapiens ◽  
Single Species ◽  
Homo Erectus ◽  
Modern Humans ◽  
Homo Neanderthalensis ◽  
Out Of Africa

I argue that the evidence of the Out-of-Africa hypothesis and the evidence of multiregional evolution of prehistorical humans can be understood if there has been interbreeding between Homo erectus, Homo neanderthalensis, and Homo sapiens at least during the preceding 700,000 years. These interbreedings require descendants who are capable of reproduction and therefore parents who belong to the same species. I suggest that a number of prehistorical humans who are at present regarded as belonging to different species belong in fact to one single species.

Taxonomic differences in deciduous upper second molar crown outlines of Homo sapiens, Homo neanderthalensis and Homo erectus

2014 ◽  
Vol 72 ◽  
pp. 1-9 ◽  
Author(s):  
Shara E. Bailey ◽  
Stefano Benazzi ◽  
Caroline Souday ◽  
Claudia Astorino ◽  
Kathleen Paul ◽  
...  
Keyword(s):  
Homo Sapiens ◽  
Homo Erectus ◽  
Second Molar ◽  
Homo Neanderthalensis
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