1
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Gilbert BLP, Kessler SE. Could care giving have altered the evolution of human immune strategies? Evol Med Public Health 2024; 12:33-49. [PMID: 38380131 PMCID: PMC10878251 DOI: 10.1093/emph/eoae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/12/2024] [Indexed: 02/22/2024] Open
Abstract
Life history theory indicates that individuals/species with a slow pace of life invest more in acquired than innate immunity. Factors that decrease the pace of life and predict greater investment in acquired immunity include increased nutritional resources, increased pathogen exposure and decreased risk of extrinsic mortality. Common care behaviors given to sick individuals produce exactly these effects: provisioning increases nutritional resources; hygiene assistance increases disease exposure of carers; and protection can reduce the risk of extrinsic mortality to sick individuals. This study, therefore, investigated under what conditions care giving behaviors might impact immune strategy and pace of life. The study employed an agent-based model approach that simulated populations with varying levels of care giving, disease mortality, disease transmissibility, and extrinsic mortality, enabling measurements of how the immune strategy and age structure of the populations changed over evolutionary time. We used multiple regressions to examine the effects of these variables on immune strategy and the age structure of the population. The findings supported our predictions that care was selected for an acquired immunity. However, the pace of life did not slow as expected. Instead, the population shifted to a faster, but also more cost-intensive reproductive strategy in which care improved child survival by subsidizing the development of acquired immune responses.
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Affiliation(s)
- Bethany L P Gilbert
- Department of Psychology, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, UK
| | - Sharon E Kessler
- Department of Psychology, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, UK
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2
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Vaill M, Kawanishi K, Varki N, Gagneux P, Varki A. Comparative physiological anthropogeny: exploring molecular underpinnings of distinctly human phenotypes. Physiol Rev 2023; 103:2171-2229. [PMID: 36603157 PMCID: PMC10151058 DOI: 10.1152/physrev.00040.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/26/2022] [Accepted: 12/28/2022] [Indexed: 01/06/2023] Open
Abstract
Anthropogeny is a classic term encompassing transdisciplinary investigations of the origins of the human species. Comparative anthropogeny is a systematic comparison of humans and other living nonhuman hominids (so-called "great apes"), aiming to identify distinctly human features in health and disease, with the overall goal of explaining human origins. We begin with a historical perspective, briefly describing how the field progressed from the earliest evolutionary insights to the current emphasis on in-depth molecular and genomic investigations of "human-specific" biology and an increased appreciation for cultural impacts on human biology. While many such genetic differences between humans and other hominids have been revealed over the last two decades, this information remains insufficient to explain the most distinctive phenotypic traits distinguishing humans from other living hominids. Here we undertake a complementary approach of "comparative physiological anthropogeny," along the lines of the preclinical medical curriculum, i.e., beginning with anatomy and considering each physiological system and in each case considering genetic and molecular components that are relevant. What is ultimately needed is a systematic comparative approach at all levels from molecular to physiological to sociocultural, building networks of related information, drawing inferences, and generating testable hypotheses. The concluding section will touch on distinctive considerations in the study of human evolution, including the importance of gene-culture interactions.
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Affiliation(s)
- Michael Vaill
- Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, California
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California
- Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California
| | - Kunio Kawanishi
- Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, California
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California
- Department of Experimental Pathology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Nissi Varki
- Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, California
- Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Pascal Gagneux
- Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, California
- Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Ajit Varki
- Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, California
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California
- Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California
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3
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Antón SC, Middleton ER. Making meaning from fragmentary fossils: Early Homo in the Early to early Middle Pleistocene. J Hum Evol 2023; 179:103307. [PMID: 37030994 DOI: 10.1016/j.jhevol.2022.103307] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 11/16/2022] [Accepted: 11/27/2022] [Indexed: 04/10/2023]
Abstract
In celebration of the 50th anniversary of the Journal of Human Evolution, we re-evaluate the fossil record for early Homo (principally Homo erectus, Homo habilis, and Homo rudolfensis) from early diversification and dispersal in the Early Pleistocene to the ultimate demise of H. erectus in the early Middle Pleistocene. The mid-1990s marked an important historical turning point in our understanding of early Homo with the redating of key H. erectus localities, the discovery of small H. erectus in Asia, and the recovery of an even earlier presence of early Homo in Africa. As such, we compare our understanding of early Homo before and after this time and discuss how the order of fossil discovery and a focus on anchor specimens has shaped, and in many ways biased, our interpretations of early Homo species and the fossils allocated to them. Fragmentary specimens may counter conventional wisdom but are often overlooked in broad narratives. We recognize at least three different cranial and two or three pelvic morphotypes of early Homo. Just one postcranial morph aligns with any certainty to a cranial species, highlighting the importance of explicitly identifying how we link specimens together and to species; we offer two ways of visualizing these connections. Chronologically and morphologically H. erectus is a member of early Homo, not a temporally more recent species necessarily evolved from either H. habilis or H. rudolfensis. Nonetheless, an ancestral-descendant notion of their evolution influences expectations around the anatomy of missing elements, especially the foot. Weak support for long-held notions of postcranial modernity in H. erectus raises the possibility of alternative drivers of dispersal. New observations suggest that the dearth of faces in later H. erectus may mask taxonomic diversity in Asia and suggest various later mid-Pleistocene populations could derive from either Asia or Africa. Future advances will rest on the development of nuanced ways to affiliate fossils, greater transparency of implicit assumptions, and attention to detailed life history information for comparative collections; all critical pursuits for future research given the great potential they have to enrich our evolutionary reconstructions for the next fifty years and beyond.
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Affiliation(s)
- Susan C Antón
- Center for the Study of Human Origins, Department of Anthropology, New York University, NY, NY 10003, USA.
| | - Emily R Middleton
- Department of Anthropology, University of Wisconsin-Milwaukee, WI 53211, USA
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4
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Introduction to special issue: The biotic context of the Early Pleistocene hominins from Dmanisi (Georgia, southern Caucasus). J Hum Evol 2023; 174:103278. [PMID: 36384082 DOI: 10.1016/j.jhevol.2022.103278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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5
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Tappen M, Bukhsianidze M, Ferring R, Coil R, Lordkipanidze D. Life and death at Dmanisi, Georgia: Taphonomic signals from the fossil mammals. J Hum Evol 2022; 171:103249. [PMID: 36116366 DOI: 10.1016/j.jhevol.2022.103249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 11/19/2022]
Abstract
There are many hypotheses regarding influences on the early hominin biogeographic spread into Eurasia; among them is increased meat-eating. Dmanisi in Georgia is one of the rare Early Pleistocene sites in Eurasia, and here we present primary information and analysis of the medium and large mammal taphonomy, contributing information about site formation and the hominins' interaction with the fauna. Nearly 85% of the specimens come from the B1 stratum. Relative abundances of mammal families demonstrate some bias toward carnivores, especially Canis borjgali, and diverse Felidae species. Bones display little weathering. Post-depositional surface modifications and matrix obscure many bone surfaces, but carnivore tooth marking is the most common bone surface modification from the nutritive taphonomic phase. Tooth pits are large, in the size range of those made by modern Crocuta crocuta and Panthera leo. Breakage variables indicate most breaks occurred while the bones were still fresh, many by carnivore consumption. Fairly even limb bone representation of herbivores suggests carcasses were introduced to the site nearly whole. Hominin tool marks are present in low frequencies, but they suggest a variety of behaviors. These marks are found on Equus, Palaeotragus, Bison, large cervids, Pseudodama, Canis, and Mammuthus. Some were made by filleting proximal limb segments, and so are likely indicative of early access to carcasses, while other marks suggest scavenging. The Homo taphonomic variables resemble the rest of the taphonomic signatures from the site with little weathering, a slightly higher percentage of their bones are whole, but only a few have probable carnivore damage. The assemblage characteristics are compared to modern actualistic and experimental assemblages, and it is concluded that Dmanisi presents a palimpsest of hyena denning, felid activity, hominin meat-eating and likely natural deaths.
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Affiliation(s)
- Martha Tappen
- Department of Anthropology, University of Minnesota, 301 19th Ave S. Minneapolis, MN 55455, USA.
| | - Maia Bukhsianidze
- Georgian National Museum, 3 Purtseladzes Str., Tbilisi, 0105, Georgia
| | - Reid Ferring
- Department of Geography and the Environment, University of North Texas, 1155 Union Circle #305279, Denton, TX, 76203, USA
| | - Reed Coil
- Department of Sociology and Anthropology, Nazarbayev University, 53 Kabanbay Batyr Avenue, Nur-Sultan, 010000, Kazakhstan
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Agustí J, Chochishvili G, Lozano-Fernández I, Furió M, Piñero P, de Marfà R. Small mammals (Insectivora, Rodentia, Lagomorpha) from the Early Pleistocene hominin-bearing site of Dmanisi (Georgia). J Hum Evol 2022; 170:103238. [PMID: 35988384 DOI: 10.1016/j.jhevol.2022.103238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 07/12/2022] [Accepted: 07/12/2022] [Indexed: 10/15/2022]
Abstract
Small mammals (insectivores, rodents, and lagomorphs) from Dmanisi are here reviewed for the first time and used as a tool for paleoenvironmental proxies. The small mammal faunal list is composed of shrews (Beremendia fissidens, cf. Beremendia minor, Crocidura kornfeldi), hamsters (Cricetulus sp., Allocricetus bursae), gerbils (Parameriones aff. obeidiyensis), murids (Apodemus cf. atavus), arvicolids (Mimomys pliocaenicus, Mimomys aff. pusillus), and pikas (Ochotona sp.). A paleoenvironmental reconstruction based on the habitat weighting method has been applied to the rodent assemblage. According to this method, the most common elements indicate an open-dry habitat (36.5%), followed by water edge (25.7%) and rocky (21.0%) elements. Open-wet (15.5%) and woodland elements (1.3%) are rare. Therefore, the habitat occupied by the hominids of Dmanisi was characterized by the prevalence of arid conditions, from steppe or semi-desert to open Mediterranean forest, with stony or rocky substrate and bushy areas. The presence of permanent aquatic environments is also documented. From a biogeographic point of view, the small mammal community from Dmanisi is composed mainly by Western or Central Asian elements, with a poor representation of European elements (Mimomys, Apodemus). It is concluded that Dmanisi hominins most possibly had ecological requirements which were different from those of the Early Pleistocene hominins from Western Europe, which settled on wetter habitats. It could be also possible that Dmanisi hominins entered Southern Caucasus at an interglacial phase before the deposition of the Dmanisi site.
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Affiliation(s)
- Jordi Agustí
- Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA), Zona Educacional 4, Campus Sescelades, Universitat Rovira i Virgili, Edifici W3, 43007 Tarragona, Spain; Àrea de Prehistòria, Universitat Rovira i Virgili, Avinguda de Catalunya 35, 43002 Tarragona, Spain; ICREA, Institució Catalana de Recerca i Estudis Avançats, Pg. Lluís Companys 23, 08010 Barcelona, Spain.
| | | | - Iván Lozano-Fernández
- Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA), Zona Educacional 4, Campus Sescelades, Universitat Rovira i Virgili, Edifici W3, 43007 Tarragona, Spain; Àrea de Prehistòria, Universitat Rovira i Virgili, Avinguda de Catalunya 35, 43002 Tarragona, Spain
| | - Marc Furió
- Serra Húnter Fellow, Universitat Autònoma de Barcelona, Geology Department, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - Pedro Piñero
- Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA), Zona Educacional 4, Campus Sescelades, Universitat Rovira i Virgili, Edifici W3, 43007 Tarragona, Spain; Àrea de Prehistòria, Universitat Rovira i Virgili, Avinguda de Catalunya 35, 43002 Tarragona, Spain
| | - Roger de Marfà
- Departament de Estratigrafia i Paleontologia, Universitat de Barcelona, 08028 Barcelona, Spain
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7
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An ancient cranium from Dmanisi: Evidence for interpersonal violence, disease, and possible predation by carnivores on Early Pleistocene Homo. J Hum Evol 2022; 166:103180. [DOI: 10.1016/j.jhevol.2022.103180] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/22/2022] [Accepted: 02/22/2022] [Indexed: 12/11/2022]
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8
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Palmqvist P, Rodríguez-Gómez G, Bermúdez de Castro JM, García-Aguilar JM, Espigares MP, Figueirido B, Ros-Montoya S, Granados A, Serrano FJ, Martínez-Navarro B, Guerra-Merchán A. Insights on the Early Pleistocene Hominin Population of the Guadix-Baza Depression (SE Spain) and a Review on the Ecology of the First Peopling of Europe. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.881651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The chronology and environmental context of the first hominin dispersal in Europe have been subject to debate and controversy. The oldest settlements in Eurasia (e.g., Dmanisi, ∼1.8 Ma) suggest a scenario in which the Caucasus and southern Asia were occupied ∼0.4 Ma before the first peopling of Europe. Barranco León (BL) and Fuente Nueva 3 (FN3), two Early Pleistocene archeological localities dated to ∼1.4 Ma in Orce (Guadix-Baza Depression, SE Spain), provide the oldest evidence of hominin presence in Western Europe. At these sites, huge assemblages of large mammals with evidence of butchery and marrow processing have been unearthed associated to abundant Oldowan tools and a deciduous tooth of Homo sp. in the case of BL. Here, we: (i) review the Early Pleistocene archeological sites of Europe; (ii) discuss on the subsistence strategies of these hominins, including new estimates of resource abundance for the populations of Atapuerca and Orce; (iii) use cartographic data of the sedimentary deposits for reconstructing the landscape habitable in Guadix-Baza; and (iv) calculate the size of the hominin population using an estimate of population density based on resource abundance. Our results indicate that Guadix-Baza could be home for a small hominin population of 350–280 individuals. This basin is surrounded by the highest mountainous reliefs of the Alpine-Betic orogen and shows a limited number of connecting corridors with the surrounding areas, which could have limited gene flow with other hominin populations. Isolation would eventually lead to bottlenecks, genetic drift and inbreeding depression, conditions documented in the wild dog population of the basin, which probably compromised the viability of the hominin population in the medium to long term. This explains the discontinuous nature of the archeological record in Guadix-Baza, a situation that can also be extrapolated to the scarcity of hominin settlements for these ancient chronologies in Europe.
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9
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Baab KL, Rogers M, Bruner E, Semaw S. Reconstruction and analysis of the DAN5/P1 and BSN12/P1 Gona Early Pleistocene Homo fossils. J Hum Evol 2021; 162:103102. [PMID: 34891069 DOI: 10.1016/j.jhevol.2021.103102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 10/18/2021] [Accepted: 10/18/2021] [Indexed: 11/18/2022]
Abstract
Two Early Pleistocene fossils from Gona, Ethiopia, were originally assigned to Homo erectus, and their differences in size and robusticity were attributed to either sexual dimorphism or anagenetic evolution. In the current study, we both revisit the taxonomic affinities of these fossils and assess whether morphological differences between them reflect temporal evolution or sexual variation. We generated virtual reconstructions of the mostly complete ∼1.55 Ma DAN5/P1 calvaria and the less complete 1.26 Ma BSN12/P1 fossil, allowing us to directly compare their anterior vault shapes using landmark-based shape analysis. The two fossils are similar in calvaria shape to H. erectus and also to other Early Pleistocene Homo species based on a geometric morphometric analysis of calvaria landmarks and semilandmarks. The DAN5/P1 fossil bears a particularly close affinity to the Georgian H. erectus fossils and to KNM-ER 1813 (H. habilis), probably reflecting allometric influences on vault shape. Combined with species-specific traits of the neurocranium (e.g., midline keeling, angular torus), we confirm that these fossils are likely early African H. erectus. We calculated regression-based estimates of endocranial volume for BSN12/P1 of 882-910 cm3 based on three virtual reconstructions. Although BSN12/P1 is markedly larger than DAN5/P1 (598 cm3), both fossils represent the smallest adult H. erectus known from their respective time periods in Africa. Some of the difference in endocranial volume between the two Gona fossils reflects broader species-level brain expansion from 1.77 to 0.01 Ma, confirmed here using a large sample (n = 38) of H. erectus. However, shape differences between these fossils did not reflect species-level changes to calvaria shape. Moreover, the analysis failed to recover a clear pattern of sexually patterned size or shape differences within H. erectus based on our current assessments of sex for individual fossils.
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Affiliation(s)
- Karen L Baab
- Department of Anatomy, Midwestern University, 19555 N. 59th Ave., Glendale, AZ 85012, USA.
| | - Michael Rogers
- Department of Anthropology, Southern Connecticut State University, 501 Crescent St., New Haven, CT 06515, USA
| | - Emiliano Bruner
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Sierra de Atapuerca 3, Burgos, 09002, Spain
| | - Sileshi Semaw
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Sierra de Atapuerca 3, Burgos, 09002, Spain; Stone Age Institute and CRAFT Research Center, 1392 W. Dittemore Rd. Gosport, IN 47408, USA
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10
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The early hunting dog from Dmanisi with comments on the social behaviour in Canidae and hominins. Sci Rep 2021; 11:13501. [PMID: 34326360 PMCID: PMC8322302 DOI: 10.1038/s41598-021-92818-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 06/16/2021] [Indexed: 02/06/2023] Open
Abstract
The renowned site of Dmanisi in Georgia, southern Caucasus (ca. 1.8 Ma) yielded the earliest direct evidence of hominin presence out of Africa. In this paper, we report on the first record of a large-sized canid from this site, namely dentognathic remains, referable to a young adult individual that displays hypercarnivorous features (e.g., the reduction of the m1 metaconid and entoconid) that allow us to include these specimens in the hypodigm of the late Early Pleistocene species Canis (Xenocyon) lycaonoides. Much fossil evidence suggests that this species was a cooperative pack-hunter that, unlike other large-sized canids, was capable of social care toward kin and non-kin members of its group. This rather derived hypercarnivorous canid, which has an East Asian origin, shows one of its earliest records at Dmanisi in the Caucasus, at the gates of Europe. Interestingly, its dispersal from Asia to Europe and Africa followed a parallel route to that of hominins, but in the opposite direction. Hominins and hunting dogs, both recorded in Dmanisi at the beginning of their dispersal across the Old World, are the only two Early Pleistocene mammal species with proved altruistic behaviour towards their group members, an issue discussed over more than one century in evolutionary biology.
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11
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Ponce de León MS, Bienvenu T, Marom A, Engel S, Tafforeau P, Alatorre Warren JL, Lordkipanidze D, Kurniawan I, Murti DB, Suriyanto RA, Koesbardiati T, Zollikofer CPE. The primitive brain of early Homo. Science 2021; 372:165-171. [PMID: 33833119 DOI: 10.1126/science.aaz0032] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/08/2020] [Accepted: 03/08/2021] [Indexed: 12/20/2022]
Abstract
The brains of modern humans differ from those of great apes in size, shape, and cortical organization, notably in frontal lobe areas involved in complex cognitive tasks, such as social cognition, tool use, and language. When these differences arose during human evolution is a question of ongoing debate. Here, we show that the brains of early Homo from Africa and Western Asia (Dmanisi) retained a primitive, great ape-like organization of the frontal lobe. By contrast, African Homo younger than 1.5 million years ago, as well as all Southeast Asian Homo erectus, exhibited a more derived, humanlike brain organization. Frontal lobe reorganization, once considered a hallmark of earliest Homo in Africa, thus evolved comparatively late, and long after Homo first dispersed from Africa.
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Affiliation(s)
- Marcia S Ponce de León
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland.
| | - Thibault Bienvenu
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland
| | - Assaf Marom
- Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Silvano Engel
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland
| | - Paul Tafforeau
- European Synchrotron Radiation Facility, 38043 Grenoble, France
| | - José Luis Alatorre Warren
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland.,Fetal Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Iwan Kurniawan
- Museum of Geology, Jln. Diponegoro 57, Bandung 40122, Indonesia
| | - Delta Bayu Murti
- Department of Anthropology, Airlangga University, Surabaya, 60115 Jawa Timur, Indonesia
| | - Rusyad Adi Suriyanto
- Laboratory of Bioanthropology and Paleoanthropology, Gadjah Mada University, Yogyakarta 55281, Indonesia
| | | | - Christoph P E Zollikofer
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland.
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12
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Coil R, Tappen M, Ferring R, Bukhsianidze M, Nioradze M, Lordkipanidze D. Spatial patterning of the archaeological and paleontological assemblage at Dmanisi, Georgia: An analysis of site formation and carnivore-hominin interaction in Block 2. J Hum Evol 2020; 143:102773. [PMID: 32272350 DOI: 10.1016/j.jhevol.2020.102773] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 01/22/2020] [Accepted: 03/02/2020] [Indexed: 11/30/2022]
Abstract
This study addresses the roles of biotic agents in site formation in the B1 strata of Block 2 at Dmanisi, Georgia, using theoretical and analogous frameworks for the interpretation of spatial behaviors of carnivores and hominins. For this study, stone material, faunal remains, and coprolites are analyzed to determine if any spatially distinct behaviors can be identified, located, and attributed to either hominins or carnivores. Faunal, stone, and coprolite assemblages are compared with each other, and lithic, taxonomic, and taphonomic subassemblages are compared with the overall distribution of their parent material. The spatial and taphonomic signatures suggest that hominin activity was only a small part of the contributing factors to site formation, whereas carnivores played a major role in the accumulation of bone.
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Affiliation(s)
- Reed Coil
- Department of Sociology and Anthropology, Nazarbayev University, 53 Kabanbay Batyr Avenue, Nur-Sult, 010000, Kazakhstan; Department of Anthropology, University of Minnesota, 395 Humphrey Center, 301 19th Ave. South, Minneapolis, MN, 55755, USA.
| | - Martha Tappen
- Department of Anthropology, University of Minnesota, 395 Humphrey Center, 301 19th Ave. South, Minneapolis, MN, 55755, USA
| | - Reid Ferring
- Department of Geography and the Environment, University of North Texas, 1155 Union Circle #305279, Denton, TX, 76203, USA
| | - Maia Bukhsianidze
- Georgian National Museum, 3/10 Shota Rustaveli Avenue, Tbilisi, 0105, Georgia
| | - Medea Nioradze
- Georgian National Museum, 3/10 Shota Rustaveli Avenue, Tbilisi, 0105, Georgia
| | - David Lordkipanidze
- Georgian National Museum, 3/10 Shota Rustaveli Avenue, Tbilisi, 0105, Georgia
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13
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Complete permanent mandibular dentition of early Homo from the upper Burgi Member of the Koobi Fora Formation, Ileret, Kenya. J Hum Evol 2019; 131:152-175. [PMID: 31182200 DOI: 10.1016/j.jhevol.2019.03.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 03/15/2019] [Accepted: 03/18/2019] [Indexed: 01/24/2023]
Abstract
The KNM-ER 64060 dentition derives from a horizon that most likely dates to between 2.02 and 2.03 Ma. A proximate series of postcranial bones (designated KNM-ER 64061) derives from the same siltstone unit and may be associated with the dentition, but their separation on the surface of the site leaves some room for doubt. KNM-ER 64060 is one of fewer than ten hominin specimens from the Early Pleistocene of East Africa that comprises a full or nearly complete mandibular dentition. Its taxonomic attribution is potentially significant, especially if the postcranial elements are related. At least three, and probably four hominin species, including Paranthropus boisei and Homo erectus (= H. ergaster), are known at about this time in East Africa. Other penecontemporaneous fossils have been referred to a single, highly variable species, H. habilis, or two taxa, namely H. habilis and H. rudolfensis. Although the weight of evidence supports the attribution of these specimens to two species, there is notable lack of agreement over the assignation of individual fossils. We take a conservative approach and group all such specimens under the designation "early Homo sp." for comparative purposes. KNM-ER 64060 is clearly attributable to Homo rather than Paranthropus. The preponderance of the evidence suggests that the affinities of KNM-ER 64060 are with fossils assigned to the early Homo sp. category rather than with H. erectus. This is indicated by the overall sizes of the KNM-ER 64060 canine, premolar and molar crowns, the size relationships of the P3 to P4, the relative narrowness of its premolar crowns, the cusp proportions of the M1 and especially those of the M2 and M3, and seemingly the possession of a two-rooted P4. Some of these comparisons suggest further that among the fossils comprising the early Homo sp. sample, the KNM-ER 64060 dentition exhibits greater overall similarity to specimens such as OH 7 and OH 16 that represent Homo habilis sensu stricto.
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Rightmire GP, Margvelashvili A, Lordkipanidze D. Variation among the Dmanisi hominins: Multiple taxa or one species? AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 168:481-495. [PMID: 30578552 DOI: 10.1002/ajpa.23759] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 11/05/2018] [Accepted: 11/06/2018] [Indexed: 11/08/2022]
Abstract
OBJECTIVES There is continuing controversy over the number of taxa documented by the Dmanisi hominins. Variation may reflect age and sex differences within a single population. Alternatively, two (or more) distinct species may be present. Our null hypothesis states that just one population is represented at the site. MATERIALS AND METHODS We assess the likely sources of variation in endocranial capacity, craniofacial and mandibular morphology, and the expression of characters related to aging and sex dimorphism. We use the coefficient of variation and a modified version of Levene's test for equal variances to compare trait variation at Dmanisi with that in fossil hominins and modern Homo sapiens from Africa. RESULTS Skull 5 presents a low, massive vault, and a muzzle-like lower face. Other individuals have larger brains and more globular vaults. Despite such variation, the five crania share numerous features. All of the mandibles possess marginal tubercles, mandibular tori, and a distinctive patterning of mental foramina. Relative variation at Dmanisi is comparable to that in selected reference groups. Further growth anticipated in Skull 3, age-related remodeling affecting the D2600 mandible, pathology, and sex dimorphism can account for much of the interindividual variation observed. The preponderance of evidence supports our null hypothesis. DISCUSSION Sources of the variation within ancient Homo assemblages remain poorly understood. Skull 5 is a very robust male, with a brain smaller than that of both a juvenile (Skull 3) and a probable female (Skull 2). Skull 1 has the largest brain, but cranial superstructures do not clearly mark this individual as male or female. It is likely that the Dmanisi hominins represent a single paleospecies of Homo displaying a pattern of sex dimorphism not seen in living hominids.
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Affiliation(s)
- G Philip Rightmire
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts
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15
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Argue D, Groves CP, Lee MS, Jungers WL. The affinities of Homo floresiensis based on phylogenetic analyses of cranial, dental, and postcranial characters. J Hum Evol 2017; 107:107-133. [DOI: 10.1016/j.jhevol.2017.02.006] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 01/09/2023]
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16
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Kessler SE, Bonnell TR, Byrne RW, Chapman CA. Selection to outsmart the germs: The evolution of disease recognition and social cognition. J Hum Evol 2017. [PMID: 28622934 DOI: 10.1016/j.jhevol.2017.02.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The emergence of providing care to diseased conspecifics must have been a turning point during the evolution of hominin sociality. On a population level, care may have minimized the costs of socially transmitted diseases at a time of increasing social complexity, although individual care-givers probably incurred increased transmission risks. We propose that care-giving likely originated within kin networks, where the costs may have been balanced by fitness increases obtained through caring for ill kin. We test a novel hypothesis of hominin cognitive evolution in which disease may have selected for the cognitive ability to recognize when a conspecific is infected. Because diseases may produce symptoms that are likely detectable via the perceptual-cognitive pathways integral to social cognition, we suggest that disease recognition and social cognition may have evolved together. Using agent-based modeling, we test 1) under what conditions disease can select for increasing disease recognition and care-giving among kin, 2) whether providing care produces greater selection for cognition than an avoidance strategy, and 3) whether care-giving alters the progression of the disease through the population. The greatest selection was produced by diseases with lower risks to the care-giver and prevalences low enough not to disrupt the kin networks. When care-giving and avoidance strategies were compared, only care-giving reduced the severity of the disease outbreaks and subsequent population crashes. The greatest selection for increased cognitive abilities occurred early in the model runs when the outbreaks and population crashes were most severe. Therefore, over the course of human evolution, repeated introductions of novel diseases into naïve populations could have produced sustained selection for increased disease recognition and care-giving behavior, leading to the evolution of increased cognition, social complexity, and, eventually, medical care in humans. Finally, we lay out predictions derived from our disease recognition hypothesis that we encourage paleoanthropologists, bioarchaeologists, primatologists, and paleogeneticists to test.
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Affiliation(s)
- Sharon E Kessler
- Department of Anthropology, McGill University, Canada; Durham University, Department of Anthropology, UK.
| | | | - Richard W Byrne
- School of Psychology and Neuroscience, University of St. Andrews, UK
| | - Colin A Chapman
- Department of Anthropology, McGill University, Canada; Wildlife Conservation Society, New York, USA
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17
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Hawks J, Elliott M, Schmid P, Churchill SE, Ruiter DJD, Roberts EM, Hilbert-Wolf H, Garvin HM, Williams SA, Delezene LK, Feuerriegel EM, Randolph-Quinney P, Kivell TL, Laird MF, Tawane G, DeSilva JM, Bailey SE, Brophy JK, Meyer MR, Skinner MM, Tocheri MW, VanSickle C, Walker CS, Campbell TL, Kuhn B, Kruger A, Tucker S, Gurtov A, Hlophe N, Hunter R, Morris H, Peixotto B, Ramalepa M, Rooyen DV, Tsikoane M, Boshoff P, Dirks PH, Berger LR. New fossil remains of Homo naledi from the Lesedi Chamber, South Africa. eLife 2017; 6. [PMID: 28483039 PMCID: PMC5423776 DOI: 10.7554/elife.24232] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/18/2017] [Indexed: 01/06/2023] Open
Abstract
The Rising Star cave system has produced abundant fossil hominin remains within the Dinaledi Chamber, representing a minimum of 15 individuals attributed to Homo naledi. Further exploration led to the discovery of hominin material, now comprising 131 hominin specimens, within a second chamber, the Lesedi Chamber. The Lesedi Chamber is far separated from the Dinaledi Chamber within the Rising Star cave system, and represents a second depositional context for hominin remains. In each of three collection areas within the Lesedi Chamber, diagnostic skeletal material allows a clear attribution to H. naledi. Both adult and immature material is present. The hominin remains represent at least three individuals based upon duplication of elements, but more individuals are likely present based upon the spatial context. The most significant specimen is the near-complete cranium of a large individual, designated LES1, with an endocranial volume of approximately 610 ml and associated postcranial remains. The Lesedi Chamber skeletal sample extends our knowledge of the morphology and variation of H. naledi, and evidence of H. naledi from both recovery localities shows a consistent pattern of differentiation from other hominin species.
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Affiliation(s)
- John Hawks
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States
| | - Marina Elliott
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Peter Schmid
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Anthropological Institute and Museum, University of Zürich, Winterthurerstr, Zürich, Switzerland
| | - Steven E Churchill
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Evolutionary Anthropology, Duke University, Durham, United States
| | - Darryl J de Ruiter
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, Texas A&M University, College Station, United States
| | - Eric M Roberts
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Hannah Hilbert-Wolf
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Heather M Garvin
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology/Archaeology, Mercyhurst University, Erie, United States.,Department of Applied Forensic Sciences, Mercyhurst University, Erie, United States
| | - Scott A Williams
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - Lucas K Delezene
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Arkansas, Fayetteville, United States
| | - Elen M Feuerriegel
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Washington, Seattle, United States
| | - Patrick Randolph-Quinney
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anatomical Sciences, University of the Witwatersrand Medical School, Johannesburg, South Africa.,School of Forensic and Applied Sciences, University of Central Lancashire, Preston, United Kingdom
| | - Tracy L Kivell
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anthropology and Conservation, University of Kent, Canterbury, United Kingdom.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Myra F Laird
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Organismal Biology and Anatomy, University of Chicago, Chicago, United States
| | - Gaokgatlhe Tawane
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Jeremy M DeSilva
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, Dartmouth College, Hanover, United States
| | - Shara E Bailey
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - Juliet K Brophy
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Geography and Anthropology, Louisiana State University, Baton Rouge, United States
| | - Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, United States
| | - Matthew M Skinner
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anthropology and Conservation, University of Kent, Canterbury, United Kingdom.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Matthew W Tocheri
- Department of Anthropology, Lakehead University, Thunder Bay, Canada.,Human Origins Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, United States
| | - Caroline VanSickle
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States.,Department of Anthropology, Bryn Mawr College, Bryn Mawr, United States
| | - Christopher S Walker
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Evolutionary Anthropology, Duke University, Durham, United States.,Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, United States
| | - Timothy L Campbell
- Department of Anthropology, Texas A&M University, College Station, United States
| | - Brian Kuhn
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
| | - Ashley Kruger
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Steven Tucker
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Alia Gurtov
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States
| | - Nompumelelo Hlophe
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Rick Hunter
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Hannah Morris
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Forestry and Natural Resources, University of Georgia, Athens, United States
| | - Becca Peixotto
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, American University, Washington, United States
| | - Maropeng Ramalepa
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Dirk van Rooyen
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Mathabela Tsikoane
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Pedro Boshoff
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Paul Hgm Dirks
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Lee R Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
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18
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Laird MF, Schroeder L, Garvin HM, Scott JE, Dembo M, Radovčić D, Musiba CM, Ackermann RR, Schmid P, Hawks J, Berger LR, de Ruiter DJ. The skull of Homo naledi. J Hum Evol 2017; 104:100-123. [DOI: 10.1016/j.jhevol.2016.09.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 09/13/2016] [Accepted: 09/15/2016] [Indexed: 01/05/2023]
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19
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Skull 5 from Dmanisi: Descriptive anatomy, comparative studies, and evolutionary significance. J Hum Evol 2017; 104:50-79. [PMID: 28317556 DOI: 10.1016/j.jhevol.2017.01.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/09/2017] [Accepted: 01/10/2017] [Indexed: 11/21/2022]
Abstract
A fifth hominin skull (cranium D4500 and mandible D2600) from Dmanisi is massively constructed, with a large face and a very small brain. Traits documented for the first time in a basal member of the Homo clade include the uniquely low ratio of endocranial volume to basicranial width, reduced vertex height, angular vault profile, smooth nasal sill coupled with a long and sloping maxillary clivus, elongated palate, and tall mandibular corpus. The convex clivus and receding symphysis of skull 5 produce a muzzle-like form similar to that of Australopithecus afarensis. While the Dmanisi cranium is very robust, differing from OH 13, OH 24, and KNM-ER 1813, it resembles Homo habilis specimens in the "squared off" outline of its maxilla in facial view, maxillary sulcus, rounded and receding zygomatic arch, and flexed zygomaticoalveolar pillar. These characters distinguish early Homo from species of Australopithecus and Paranthropus. Skull 5 is unlike Homo rudolfensis cranium KNM-ER 1470. Although it appears generally primitive, skull 5 possesses a bar-like supraorbital torus, elongated temporal squama, occipital transverse torus, and petrotympanic traits considered to be derived for Homo erectus. As a group, the Dmanisi crania and mandibles display substantial anatomical and metric variation. A key question is whether the fossils document age-related growth and sex dimorphism within a single population, or whether two (or more) distinct taxa may be present at the site. We use the coefficient of variation to compare Dmanisi with Paranthropus boisei, H. erectus, and recent Homo sapiens, finding few signals that the Dmanisi sample is excessively variable in comparison to these reference taxa. Using cranial measurements and principal components analysis, we explore the proposal that the Dmanisi skulls can be grouped within a regionally diverse hypodigm for H. erectus. Our results provide only weak support for this hypothesis. Finally, we consider all available morphological and paleobiological evidence in an attempt to clarify the phyletic relationship of Dmanisi to Homo species evolving >2.0 to 1.0 Ma.
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20
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Comparative perspective on antemortem tooth loss in Neandertals. J Hum Evol 2016; 92:80-90. [PMID: 26989018 DOI: 10.1016/j.jhevol.2015.10.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 06/06/2015] [Accepted: 10/24/2015] [Indexed: 11/21/2022]
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21
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Baab KL. The role of neurocranial shape in defining the boundaries of an expanded Homo erectus hypodigm. J Hum Evol 2016; 92:1-21. [DOI: 10.1016/j.jhevol.2015.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 11/05/2015] [Accepted: 11/06/2015] [Indexed: 01/08/2023]
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22
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Margvelashvili A, Zollikofer CPE, Lordkipanidze D, Tafforeau P, Ponce de León MS. Comparative analysis of dentognathic pathologies in the Dmanisi mandibles. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 160:229-53. [PMID: 26919277 DOI: 10.1002/ajpa.22966] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 01/20/2016] [Accepted: 02/02/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Due to the scarcity of the fossil record, in vivo changes in the dentognathic system of early Homo are typically documented at the level of individual fossil specimens, and it remains difficult to draw population-level inferences about dietary habits, diet-related activities and lifestyle from individual patterns of dentognathic alterations. The Plio-Pleistocene hominin sample from Dmanisi (Georgia), dated to 1.77 million years ago, offers a unique opportunity to study in vivo changes in the dentognathic system of individuals belonging to a single paleodeme of early Homo. MATERIALS AND METHODS We analyze dentognathic pathologies in the Dmanisi sample, and in comparative samples of modern Australian and Greenlander hunter-gatherer populations, applying clinical protocols of dentognathic diagnostics. RESULTS The Dmanisi hominins exhibit a similarly wide diversity and similar incidence of dentognathic pathologies as the modern human hunter-gatherer population samples investigated here. Dmanisi differs from the modern population samples in several respects: At young age tooth wear is already advanced, and pathologies are more prevalent. At old age, hypercementosis is substantial. CONCLUSIONS Results indicate that dentognathic pathologies and disease trajectories are largely similar in early Homo and modern humans, but that the disease load was higher in early Homo, probably as an effect of higher overall stress on the dentognathic system. Am J Phys Anthropol 160:229-253, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Ann Margvelashvili
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, Zurich, CH-8057, Switzerland.,Georgian National Museum, Purtseladze 3, Tbilisi, 0105, Georgia
| | - Christoph P E Zollikofer
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, Zurich, CH-8057, Switzerland
| | | | - Paul Tafforeau
- European Synchrotron Radiation Facility, 71 avenue des martyrs, 38043, Grenoble, France
| | - Marcia S Ponce de León
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, Zurich, CH-8057, Switzerland
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23
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Guimarães SWF, Lorenzo C. Variability in first Homo: Analysis of the ratio between the skulls KNM-ER 1470 and KNM-ER 1813 based on sexual dimorphism of Homo sapiens. HOMO-JOURNAL OF COMPARATIVE HUMAN BIOLOGY 2015; 66:387-98. [PMID: 26092693 DOI: 10.1016/j.jchb.2015.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Accepted: 02/15/2015] [Indexed: 10/23/2022]
Abstract
The study of the skulls KNM-ER 1470 and KNM-ER 1813, considered the first members of the genus Homo, has raised some debates. While some of researchers maintain that there is only one species, another group argues that there are two species. On one hand these two fossils are still taxonomically undetermined, on the other hand they bring up another problem related to the existence of a genus with multiple species since its beginning, according to the last discoveries. In this paper, we have compared the size ratio between these fossils with ratios established in populations of Homo sapiens, in order to know if they fit into the human standard, considering intra-sexual and inter-sexual variation. Results help to establish whether these fossils correspond to different species or their differences could be related to sexual dimorphism within a single species.
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Affiliation(s)
- S W Ferreira Guimarães
- Universidade Federal do Pará, Rua Augusto Corrêa, 1, 66075-110, Belém, PA, Brazil; Instituto Terra e Memória, largo Infante Dom Henrique, Museu de Arte Pré-histórica, 6120-721 Mação, Portugal.
| | - C Lorenzo
- Área de Prehistoria, Facultat de Lletres, Universitat Rovira i Virgili, Av. Catalunya, 35, E-43002 Tarragona, Spain; Institut de Paleoecologia Humana i Evolució Social, Excorxador s/n, E-43005 Tarragona, Spain
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24
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Mathewson I. Did human hairlessness allow natural photobiomodulation 2 million years ago and enable photobiomodulation therapy today? This can explain the rapid expansion of our genus’s brain. Med Hypotheses 2015; 84:421-8. [DOI: 10.1016/j.mehy.2015.01.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 12/19/2014] [Accepted: 01/21/2015] [Indexed: 12/26/2022]
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25
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Zhu ZY, Dennell R, Huang WW, Wu Y, Rao ZG, Qiu SF, Xie JB, Liu W, Fu SQ, Han JW, Zhou HY, Ou Yang TP, Li HM. New dating of the Homo erectus cranium from Lantian (Gongwangling), China. J Hum Evol 2015; 78:144-57. [DOI: 10.1016/j.jhevol.2014.10.001] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 10/01/2014] [Accepted: 10/03/2014] [Indexed: 11/16/2022]
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26
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A re-examination of the human fossil specimen from Bački Petrovac (Serbia). HOMO-JOURNAL OF COMPARATIVE HUMAN BIOLOGY 2014; 65:281-95. [PMID: 24951407 DOI: 10.1016/j.jchb.2014.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 01/31/2014] [Indexed: 11/22/2022]
Abstract
A fragmented human calotte was discovered during the early 1950s near Bački Petrovac (Serbia), in association with Palaeolithic stone tools. After its initial publication, the fossil specimen remained largely unknown outside of the Serbian academe and no detailed comparative study has ever been carried out. Since the whereabouts of the fossil itself are currently unknown, and given its potential significance for the Pleistocene human evolution, we re-examine the data published by Živanović (1966, 1975). Using the original measurements, mostly taken on the frontal bone, and a wide comparative sample of 68 fossil specimens, the fossil was compared and analyzed by statistical multivariate methods. We also conducted a visual examination of the morphology based on the available photographic material. Our analysis reveals phenetic similarity with Middle Pleistocene archaic Homo from Africa and anatomically modern Homo sapiens. However, the absence of primitive cranial traits in Bački Petrovac indicates a clear modern Homo sapiens designation. Although lost at the moment, there is a chance for the re-discovery of the fossil in the years to come. This would give us an opportunity to acquire absolute dates and to study the specimen in a more detailed manner.
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Arsuaga JL, Martinez I, Arnold LJ, Aranburu A, Gracia-Tellez A, Sharp WD, Quam RM, Falgueres C, Pantoja-Perez A, Bischoff J, Poza-Rey E, Pares JM, Carretero JM, Demuro M, Lorenzo C, Sala N, Martinon-Torres M, Garcia N, Alcazar de Velasco A, Cuenca-Bescos G, Gomez-Olivencia A, Moreno D, Pablos A, Shen CC, Rodriguez L, Ortega AI, Garcia R, Bonmati A, Bermudez de Castro JM, Carbonell E. Neandertal roots: Cranial and chronological evidence from Sima de los Huesos. Science 2014; 344:1358-63. [DOI: 10.1126/science.1253958] [Citation(s) in RCA: 305] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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28
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Bermúdez de Castro JM, Martinón-Torres M, Sier MJ, Martín-Francés L. On the variability of the Dmanisi mandibles. PLoS One 2014; 9:e88212. [PMID: 24586309 PMCID: PMC3930530 DOI: 10.1371/journal.pone.0088212] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/03/2014] [Indexed: 11/18/2022] Open
Abstract
The description of a new skull (D4500) from the Dmanisi site (Republic of Georgia) has reopened the debate about the morphological variability within the genus Homo. The new skull fits with a mandible (D2600) often referred as 'big' or 'enigmatic' because of its differences with the other Dmanisi mandibles (D211 and D2735). In this report we present a comparative study of the variability of the Dmanisi mandibles under a different perspective, as we focus in morphological aspects related to growth and development. We have followed the notion of modularity and phenotypic integration in order to understand the architectural differences observed within the sample. Our study reveals remarkable shape differences between D2600 and the other two mandibles, that are established early in the ontogeny (during childhood or even before) and that do not depend on size or sexual dimorphism. In addition, D2600 exhibits a mosaic of primitive and derived features regarding the Homo clade, which is absent in D211 and D2735. This mosaic expression is related to the location of the features and can be explained under the concept of modularity. Our study would support the possibility of two different paleodemes represented at the Dmanisi site. This hypothesis has been previously rejected on the basis that all the individuals were constrained in the same stratigraphic and taphonomic settings. However, our revision of the complex Dmanisi stratigraphy suggests that the accumulation could cover an undetermined period of time. Even if "short" in geological terms, the hominin accumulation was not necessarily synchronic. In the same line we discard that the differences between D2600 and the small mandibles are consequence of wear-related dentoalveolar remodeling. In addition, dental wear pattern of D2600 could suggest an adaptation to a different ecological niche than the other Dmanisi individuals.
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Affiliation(s)
| | - María Martinón-Torres
- Dental Anthropology Group, National Research Center on Human Evolution (CENIEH), Burgos, Spain
| | - Mark Jan Sier
- Dental Anthropology Group, National Research Center on Human Evolution (CENIEH), Burgos, Spain
- Paleomagnetic Laboratory ‘Fort Hoofddijk’, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands
- Human Origins Group, Faculty of Archaeology, Leiden University, Leiden, The Netherlands
| | - Laura Martín-Francés
- Dental Anthropology Group, National Research Center on Human Evolution (CENIEH), Burgos, Spain
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Simpson SW, Quade J, Levin NE, Semaw S. The female Homo pelvis from Gona: response to Ruff (2010). J Hum Evol 2014; 68:32-5. [PMID: 24560347 DOI: 10.1016/j.jhevol.2013.12.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 10/21/2013] [Accepted: 12/10/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Scott W Simpson
- Department of Anatomy, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106-4930, USA; Institute for the Science of Origins, Case Western Reserve University, Cleveland, OH 44106, USA; Laboratory of Physical Anthropology, Cleveland Museum of Natural History, Cleveland, OH 44106, USA.
| | - Jay Quade
- Department of Geosciences, University of Arizona, Tucson, AZ, USA
| | - Naomi E Levin
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Sileshi Semaw
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Sierra de Atapuerca s/n, 09002 Burgos, Spain; The Stone Age Institute, 1392 West Dittemore Road, Gosport, IN 47433, USA; CRAFT, Indiana University, Bloomington, IN 47405, USA
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Lordkipanidze D, Ponce de León MS, Margvelashvili A, Rak Y, Rightmire GP, Vekua A, Zollikofer CPE. A complete skull from Dmanisi, Georgia, and the evolutionary biology of early Homo. Science 2013; 342:326-31. [PMID: 24136960 DOI: 10.1126/science.1238484] [Citation(s) in RCA: 321] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
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.
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Tooth wear and dentoalveolar remodeling are key factors of morphological variation in the Dmanisi mandibles. Proc Natl Acad Sci U S A 2013; 110:17278-83. [PMID: 24101504 DOI: 10.1073/pnas.1316052110] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Plio-Pleistocene hominin sample from Dmanisi (Georgia), dated to 1.77 million years ago, is unique in offering detailed insights into patterns of morphological variation within a paleodeme of early Homo. Cranial and dentoalveolar morphologies exhibit a high degree of diversity, but the causes of variation are still relatively unexplored. Here we show that wear-related dentoalveolar remodeling is one of the principal mechanisms causing mandibular shape variation in fossil Homo and in modern human hunter-gatherer populations. We identify a consistent pattern of mandibular morphological alteration, suggesting that dental wear and compensatory remodeling mechanisms remained fairly constant throughout the evolution of the genus Homo. With increasing occlusal and interproximal tooth wear, the teeth continue to erupt, the posterior dentition tends to drift in a mesial direction, and the front teeth become more upright. The resulting changes in dentognathic size and shape are substantial and need to be taken into account in comparative taxonomic analyses of isolated hominin mandibles. Our data further show that excessive tooth wear eventually leads to a breakdown of the normal remodeling mechanisms, resulting in dentognathic pathologies, tooth loss, and loss of masticatory function. Complete breakdown of dentognathic homeostasis, however, is unlikely to have limited the life span of early Homo because this effect was likely mediated by the preparation of soft foods.
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Rightmire GP. Homo erectus and Middle Pleistocene hominins: Brain size, skull form, and species recognition. J Hum Evol 2013; 65:223-52. [DOI: 10.1016/j.jhevol.2013.04.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 04/09/2013] [Accepted: 04/25/2013] [Indexed: 12/27/2022]
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33
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Mojokerto revisited: Evidence for an intermediate pattern of brain growth in Homo erectus. J Hum Evol 2013; 65:156-61. [DOI: 10.1016/j.jhevol.2013.04.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 04/26/2013] [Accepted: 04/27/2013] [Indexed: 11/22/2022]
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34
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Abstract
Two new fossil jawbones from Kenya are claimed to confirm a diversity of early Homo species. However, archaic species concepts and an inadequate fossil record continue to obscure the origins of our genus.
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Affiliation(s)
- Tim White
- Human Evolution Research Center (HERC) and Department of Integrative Biology, 3101 Valley Life Sciences Building, UC Berkeley, Berkeley, CA 94720, USA.
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35
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Van Arsdale AP, Wolpoff MH. A SINGLE LINEAGE IN EARLY PLEISTOCENEHOMO: SIZE VARIATION CONTINUITY IN EARLY PLEISTOCENEHOMOCRANIA FROM EAST AFRICA AND GEORGIA. Evolution 2012; 67:841-50. [DOI: 10.1111/j.1558-5646.2012.01824.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Grimaud-Hervé D, Widianto H, Détroit F, Sémah F. Comparative morphological and morphometric description of the hominin calvaria from Bukuran (Sangiran, Central Java, Indonesia). J Hum Evol 2012; 63:637-52. [DOI: 10.1016/j.jhevol.2012.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 07/13/2012] [Accepted: 07/13/2012] [Indexed: 11/28/2022]
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38
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Abstract
Hominin evolution is characterized by two main trends, transition to bipedality and increase in brain size. Fossil evidence shows that both trends had a major impact on the structure and function of the hominin skull. This chapter asks how evolutionary modification of the cranial ontogenetic program led to morphological reorganization of the hominin skull and ultimately to hominin cranial diversity. Three major mechanisms of evolutionary developmental reorganization are proposed: modified prenatal development of the cranial base and face reflects adaptation to bipedality; high rates of neurocranial growth during early postnatal ontogeny are essential to attain large brain sizes; taxon-specific modification of facial development reflects dietary adaptation and-in the genus Homo-a general trend toward neoteny.
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Craniofacial morphology of Homo floresiensis: Description, taxonomic affinities, and evolutionary implication. J Hum Evol 2011; 61:644-82. [DOI: 10.1016/j.jhevol.2011.08.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 08/19/2011] [Accepted: 08/21/2011] [Indexed: 11/19/2022]
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40
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Balzeau A, Grimaud-Hervé D, Gilissen E. Where are inion and endinion? Variations of the exo- and endocranial morphology of the occipital bone during hominin evolution. J Hum Evol 2011; 61:488-502. [DOI: 10.1016/j.jhevol.2011.07.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 06/30/2011] [Accepted: 07/03/2011] [Indexed: 11/29/2022]
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41
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Kaifu Y, Zaim Y, Baba H, Kurniawan I, Kubo D, Rizal Y, Arif J, Aziz F. New reconstruction and morphological description of a Homo erectus cranium: Skull IX (Tjg-1993.05) from Sangiran, Central Java. J Hum Evol 2011; 61:270-94. [DOI: 10.1016/j.jhevol.2011.04.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 02/21/2011] [Accepted: 04/03/2011] [Indexed: 11/30/2022]
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42
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Mgeladze A, Lordkipanidze D, Moncel MH, Despriee J, Chagelishvili R, Nioradze M, Nioradze G. Hominin occupations at the Dmanisi site, Georgia, Southern Caucasus: raw materials and technical behaviours of Europe's first hominins. J Hum Evol 2011; 60:571-96. [PMID: 21277002 DOI: 10.1016/j.jhevol.2010.10.008] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 10/05/2010] [Accepted: 10/09/2010] [Indexed: 11/25/2022]
Abstract
Dmanisi is the oldest site outside of Africa that records unquestioned hominin occupations as well as the dispersal of hominins in Europe and Asia. The site has yielded large numbers of artefacts from several periods of hominin occupation. This analysis of Dmanisi stone tool technology includes a review of all the pieces recovered during the last 15 years of excavations. This lithic assemblage gives insights into the hominin behaviour at 1.7-1.8 Ma in Eurasia. Dmanisi hominins exploited local rocks derived from either nearby riverbeds or outcrops, and petrographic study provides data on patterns of stone procurement. Recent geological surveys and technological studies of the artefacts illustrate the roles of hominins in composing the assemblage. Dmanisi hominins selected two types of blanks, including cobbles and angular blocks, of basalt, andesite, and tuffs. Many complete cobbles, pebbles, and rolled blocks in basalt were unmodified, and geological analyses and surveys indicate that hominins brought manuports back to the site, suggesting a complex procurement strategy. Cores, flakes and debris show that all stages of flaking activity took place at the site. Numerous unifacial cores suggest that knapping was not very elaborate. Centripetal knapping is observed on some flake-cores. Knapping was influenced by the blank shape and natural angles. Most flaked objects were either cores or chopper-cores. Flakes predominate while flake tools are rare. The Dmanisi lithic assemblage is comparable to Oldowan sites in Africa in terms of reduction sequence, organisation of the removals, platform types, and the lack of retouched flakes. Dmanisi artefacts and may have been produced by the original hominins in Europe and Asia.
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Jashashvili T, Ponce de León MS, Lordkipanidze D, Zollikofer CPE. First evidence of a bipartite medial cuneiform in the hominin fossil record: a case report from the Early Pleistocene site of Dmanisi. J Anat 2011; 216:705-16. [PMID: 20579174 DOI: 10.1111/j.1469-7580.2010.01236.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A medial cuneiform exhibiting complete bipartition was discovered at the Early Pleistocene site of Dmanisi, Georgia. The specimen is the oldest known instance of this anatomical variant in the hominin fossil record. Here we compare developmental variation of the medial cuneiform in fossil hominins, extant humans and great apes, and discuss potential implications of bipartition for hominin foot phylogeny and function. Complete bipartition is rare among modern humans (< 1%); incomplete bipartition was found in 2 of 200 examined great ape specimens and also appears in the form of a divided distal articular surface in the Stw573c Australopithecus africanus specimen. Although various developmental pathways lead to medial cuneiform bipartition, it appears that the bipartite bone does not deviate significantly from normal overall morphology. Together, these data indicate that bipartition represents a phyletically old developmental variant of the medial cuneiform, which does not, however, affect the species-specific morphology and function of this bone.
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Affiliation(s)
- Tea Jashashvili
- Anthropological Institute and Museum, University of Zurich, Zurich, Switzerland.
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44
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Indriati E, Antón SC. The calvaria of Sangiran 38, Sendangbusik, Sangiran Dome, Java. HOMO-JOURNAL OF COMPARATIVE HUMAN BIOLOGY 2010; 61:225-43. [DOI: 10.1016/j.jchb.2010.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Accepted: 05/26/2010] [Indexed: 11/27/2022]
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45
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46
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47
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Millette JB, Sauther ML, Cuozzo FP. Behavioral responses to tooth loss in wild ring-tailed lemurs (Lemur catta) at the Beza Mahafaly Special Reserve, Madagascar. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2009; 140:120-34. [DOI: 10.1002/ajpa.21045] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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48
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Weston EM, Lister AM. Insular dwarfism in hippos and a model for brain size reduction in Homo floresiensis. Nature 2009; 459:85-8. [PMID: 19424156 PMCID: PMC2679980 DOI: 10.1038/nature07922] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 02/19/2009] [Indexed: 12/02/2022]
Abstract
Body size reduction in mammals is usually associated with only moderate brain size reduction as the brain and sensory organs complete their growth before the rest of the body during ontogeny1,2. On this basis “phyletic dwarfs” are predicted to have a higher relative brain size than “phyletic giants”1,3. This trend has been questioned, however, in the special case of dwarfism of mammals on islands4. Here we show that the endocranial capacities of extinct dwarf species of hippopotamus from Madagascar are up to 30% smaller than those of a mainland African ancestor scaled to equivalent body mass. These results show brain size reduction is much greater than predicted from an intraspecific ‘late ontogenetic’ model of dwarfism where brain size scales to body size with an exponent of 0.35. The nature of the proportional change or grade shift2,5 observed here indicates that selective pressures upon brain size are potentially independent from those on body size. This study demonstrates empirically that it is mechanistically possible for dwarf mammals on islands to evolve significantly smaller brains than would be predicted from a model of dwarfing based on the intraspecific scaling of the mainland ancestor. Our findings challenge our understanding of brain-body allometric relationships in mammals and suggest that the process of dwarfism could in principle explain small brain size, a factor relevant to the interpretation of the small-brained hominin found on the Island of Flores, Indonesia6.
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Affiliation(s)
- Eleanor M Weston
- Department of Palaeontology, Natural History Museum, London SW7 5BD, UK.
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49
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Ruff C. Relative limb strength and locomotion in Homo habilis. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2009; 138:90-100. [PMID: 18711733 DOI: 10.1002/ajpa.20907] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
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.
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Affiliation(s)
- Christopher Ruff
- Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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50
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Roche H, Blumenschine RJ, Shea JJ. Origins and Adaptations of Early Homo: What Archeology Tells Us. VERTEBRATE PALEOBIOLOGY AND PALEOANTHROPOLOGY 2009. [DOI: 10.1007/978-1-4020-9980-9_12] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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