Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Assunto da revista
Intervalo de ano de publicação
2.
Sci Adv ; 6(10): eaaw4694, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32181331

RESUMO

Although stone tools generally co-occur with early members of the genus Homo, they are rarely found in direct association with hominins. We report that both Acheulian and Oldowan artifacts and Homo erectus crania were found in close association at 1.26 million years (Ma) ago at Busidima North (BSN12), and ca. 1.6 to 1.5 Ma ago at Dana Aoule North (DAN5) archaeological sites at Gona, Afar, Ethiopia. The BSN12 partial cranium is robust and large, while the DAN5 cranium is smaller and more gracile, suggesting that H. erectus was probably a sexually dimorphic species. The evidence from Gona shows behavioral diversity and flexibility with a lengthy and concurrent use of both stone technologies by H. erectus, confounding a simple "single species/single technology" view of early Homo.


Assuntos
Evolução Biológica , Fósseis , Hominidae , Crânio/anatomia & histologia , Animais , Etiópia , Hominidae/anatomia & histologia , Hominidae/classificação , Humanos , Paleontologia
3.
Proc Biol Sci ; 270 Suppl 1: S15-7, 2003 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-12952624

RESUMO

Dental traits have long been assumed to be under selection in mammals, based on the macroevolutionary correlation between dental morphology and feeding behaviour. However, natural selection acting on dental morphology has rarely, if ever, been documented in wild populations. We investigated the possibility of microevolutionary selection on dental traits by measuring molar breadth in a sample of Alouatta palliata (mantled howler monkey) crania from Barro Colorado Island (BCI), Panama. The age at death of the monkeys is an indicator of their fitness, since they were all found dead of natural causes. Howlers with small molars have significantly decreased fitness as they die, on average, at an earlier age (well before sexual maturity) than those with larger molars. This documents the existence of phenotypic viability selection on molar tooth size in the BCI howlers, regardless of causality or heritability. The selection is further shown to occur during the weaning phase of A. palliata life history, establishing a link between this period of increased mortality and selection on a specific morphological feature. These results provide initial empirical support for the long-held assumption that primate molar size is under natural selection.


Assuntos
Alouatta/genética , Dente Molar/anatomia & histologia , Animais , Animais Selvagens , Dente Molar/crescimento & desenvolvimento , Panamá , Seleção Genética
4.
Science ; 322(5904): 1089-92, 2008 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19008443

RESUMO

Analyses of the KNM-WT 15000 Homo erectus juvenile male partial skeleton from Kenya concluded that this species had a tall thin body shape due to specialized locomotor and climatic adaptations. Moreover, it was concluded that H. erectus pelves were obstetrically restricted to birthing a small-brained altricial neonate. Here we describe a nearly complete early Pleistocene adult female H. erectus pelvis from the Busidima Formation of Gona, Afar, Ethiopia. This obstetrically capacious pelvis demonstrates that pelvic shape in H. erectus was evolving in response to increasing fetal brain size. This pelvis indicates that neither adaptations to tropical environments nor endurance running were primary selective factors in determining pelvis morphology in H. erectus during the early Pleistocene.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Vértebras Lombares/anatomia & histologia , Ossos Pélvicos/anatomia & histologia , Adaptação Biológica , Animais , Animais Recém-Nascidos , Evolução Biológica , Estatura , Tamanho Corporal , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Meio Ambiente , Etiópia , Feminino , Hominidae/fisiologia , Humanos , Locomoção , Parto , Pelve/anatomia & histologia , Sacro/anatomia & histologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA