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1.
Nature ; 575(7783): 489-493, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695194

RESUMO

Many ideas have been proposed to explain the origin of bipedalism in hominins and suspension in great apes (hominids); however, fossil evidence has been lacking. It has been suggested that bipedalism in hominins evolved from an ancestor that was a palmigrade quadruped (which would have moved similarly to living monkeys), or from a more suspensory quadruped (most similar to extant chimpanzees)1. Here we describe the fossil ape Danuvius guggenmosi (from the Allgäu region of Bavaria) for which complete limb bones are preserved, which provides evidence of a newly identified form of positional behaviour-extended limb clambering. The 11.62-million-year-old Danuvius is a great ape that is dentally most similar to Dryopithecus and other European late Miocene apes. With a broad thorax, long lumbar spine and extended hips and knees, as in bipeds, and elongated and fully extended forelimbs, as in all apes (hominoids), Danuvius combines the adaptations of bipeds and suspensory apes, and provides a model for the common ancestor of great apes and humans.


Assuntos
Fósseis , Hominidae/classificação , Hominidae/fisiologia , Locomoção , Filogenia , Posição Ortostática , Animais , Extremidades/anatomia & histologia , Feminino , Hominidae/anatomia & histologia , Humanos , Masculino , Tíbia/anatomia & histologia , Ulna/anatomia & histologia
2.
Elife ; 72018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30296996

RESUMO

Flying squirrels are the only group of gliding mammals with a remarkable diversity and wide geographical range. However, their evolutionary story is not well known. Thus far, identification of extinct flying squirrels has been exclusively based on dental features, which, contrary to certain postcranial characters, are not unique to them. Therefore, fossils attributed to this clade may indeed belong to other squirrel groups. Here we report the oldest fossil skeleton of a flying squirrel (11.6 Ma) that displays the gliding-related diagnostic features shared by extant forms and allows for a recalibration of the divergence time between tree and flying squirrels. Our phylogenetic analyses combining morphological and molecular data generally support older dates than previous molecular estimates (~23 Ma), being congruent with the inclusion of some of the earliest fossils (~36 Ma) into this clade. They also show that flying squirrels experienced little morphological change for almost 12 million years.


Assuntos
Osso e Ossos/anatomia & histologia , Fósseis , Sciuridae/anatomia & histologia , Esqueleto/anatomia & histologia , Animais , Citocromos b/genética , Variação Genética , Geografia , Filogenia , RNA Ribossômico/genética , Sciuridae/classificação , Sciuridae/genética , Espanha , Fatores de Tempo
3.
PLoS One ; 12(5): e0177347, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28531204

RESUMO

Dating fossil hominids and reconstructing their environments is critically important for understanding human evolution. Here we date the potentially oldest hominin, Graecopithecus freybergi from Europe and constrain the environmental conditions under which it thrived. For the Graecopithecus-bearing Pikermi Formation of Attica/Greece, a saline aeolian dust deposit of North African (Sahara) provenance, we obtain an age of 7.37-7.11 Ma, which is coeval with a dramatic cooling in the Mediterranean region at the Tortonian-Messinian transition. Palaeobotanic proxies demonstrate C4-grass dominated wooded grassland-to-woodland habitats of a savannah biome for the Pikermi Formation. Faunal turnover at the Tortonian-Messinian transition led to the spread of new mammalian taxa along with Graecopithecus into Europe. The type mandible of G. freybergi from Pyrgos (7.175 Ma) and the single tooth (7.24 Ma) from Azmaka (Bulgaria) represent the first hominids of Messinian age from continental Europe. Our results suggest that major splits in the hominid family occurred outside Africa.


Assuntos
Antropologia Física/métodos , Hominidae/fisiologia , Mandíbula/anatomia & histologia , Dente/anatomia & histologia , África , Animais , Evolução Biológica , Meio Ambiente , Europa (Continente) , Fósseis , Hominidae/anatomia & histologia , Filogeografia , Datação Radiométrica
4.
J Hum Evol ; 61(3): 332-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21665243

RESUMO

The paleobiogeography of hominoids exhibits a puzzling pattern of migrations between and within Africa and Eurasia. A precise dating of hominoid-bearing localities is therefore essential to reveal the timing, direction and possible causes of dispersals. Here, we present a bio-magnetostratigraphic analysis of the section of Engelswies (Southern Germany, Upper Freshwater Molasse, North Alpine Foreland Basin) where the oldest Eurasian hominoid was found. Our paleomagnetic results reveal a very short normal and a reverse magnetic polarity for the entire section. The polarity record is correlated to the Astronomical Tuned Neogene Time Scale using an integrated stratigraphic approach. This approach follows the chronostratigraphic framework for the Upper Freshwater Molasse, which combines magnetostratigraphy with biostratigraphic, lithostratigraphic and (40)Ar/(39)Ar dating results. According to this outcome, the reverse polarity of the Engelswies section most likely correlates to magnetochron C5Cr. The origin of the short normal polarity remains enigmatic. The magnetostratigraphic calibration and the evolutionary level of the Engelswies small mammal fauna suggest an age of 17.1-17.0Ma (Early Karpatian, Early Miocene) for the oldest Eurasian hominoid, and roughly confirm the estimates of Heizmann and Begun (2001). The estimated age suggests that the first hominoids in Eurasia are contemporaneous with Afro-Arabian afropithecins, and dispersal may have been facilitated by intra-Burdigalian (∼18-17Ma) sea-level low stands and the beginning of the Miocene Climate Optimum. The paleoclimatic and environmental reconstruction of the Engelswies locality indicates a lakeshore environment near dense subtropical rain forest vegetation, where paratropical temperatures (mean annual temperature around 20°C) and humid conditions (mean annual precipitation>1.100mm) prevailed.


Assuntos
Catarrinos/fisiologia , Fenômenos Magnéticos , Paleontologia , Animais , Evolução Biológica , Catarrinos/classificação , Meio Ambiente , Fósseis , Alemanha , Mamíferos/classificação , Filogenia
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