Journal ArticleDOI
Asa Issie, Aramis and the origin of Australopithecus
Tim D. White,Tim D. White,Giday WoldeGabriel,Berhane Asfaw,Stan Ambrose,Yonas Beyene,Raymond L. Bernor,Jean-Renaud Boisserie,Brian S. Currie,Henry Gilbert,Yohannes Haile-Selassie,William K. Hart,Leslea J. Hlusko,F. Clark Howell,Reiko T. Kono,Thomas Lehmann,Antoine Louchart,C. Owen Lovejoy,Paul R. Renne,Paul R. Renne,Haruo Saegusa,Elisabeth S. Vrba,Hank Wesselman,Gen Suwa +23 more
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New fossils from the Middle Awash study area that extend the known Au.Abstract:
The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central problem in human evolutionary studies. Australopithecus species differ markedly from extant African apes and candidate ancestral hominids such as Ardipithecus, Orrorin and Sahelanthropus. The earliest described Australopithecus species is Au. anamensis, the probable chronospecies ancestor of Au. afarensis. Here we describe newly discovered fossils from the Middle Awash study area that extend the known Au. anamensis range into northeastern Ethiopia. The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1-4.2 million years ago. They include diagnostic craniodental remains, the largest hominid canine yet recovered, and the earliest Australopithecus femur. These new fossils are sampled from a woodland context. Temporal and anatomical intermediacy between Ar. ramidus and Au. afarensis suggest a relatively rapid shift from Ardipithecus to Australopithecus in this region of Africa, involving either replacement or accelerated phyletic evolution.read more
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Ardipithecus ramidus and the Paleobiology of Early Hominids
Tim D. White,Berhane Asfaw,Yonas Beyene,Yohannes Haile-Selassie,C. Owen Lovejoy,Gen Suwa,Giday WoldeGabriel +6 more
TL;DR: Ardipithecus ramidus indicates that despite the genetic similarities of living humans and chimpanzees, the ancestor the authors last shared probably differed substantially from any extant African ape.
Journal ArticleDOI
Woody cover and hominin environments in the past 6 million years
Thure E. Cerling,Jonathan G. Wynn,Samuel A. Andanje,Michael I. Bird,David Kimutai Korir,Naomi E. Levin,William D. Mace,Anthony N. Macharia,Jay Quade,Christopher H. Remien +9 more
TL;DR: It is shown that the fraction of woody cover in tropical ecosystems can be quantified using stable carbon isotopes in soils, and 13C/12C ratio data point to the prevalence of open environments at the majority of hominin fossil sites in eastern Africa over the past 6 million years.
Journal ArticleDOI
High- and low-latitude forcing of Plio-Pleistocene East African climate and human evolution.
Martin H. Trauth,Mark A. Maslin,Alan L. Deino,Manfred R. Strecker,Andreas G.N. Bergner,Miriam Dühnforth +5 more
TL;DR: High-latitude forcing is required to compress the Intertropical Convergence Zone so that East Africa becomes locally sensitive to precessional forcing, resulting in rapid shifts from wet to dry conditions.
Journal ArticleDOI
The Pelvis and Femur of Ardipithecus ramidus: The Emergence of Upright Walking
TL;DR: The femur and pelvis of Ardipithecus ramidus have characters indicative of both upright bipedal walking and movement in trees, and they therefore bear little or no functional relationship to the highly derived suspension, vertical climbing, knuckle-walking and facultative bipedality of extant African apes.
Journal ArticleDOI
Diet of Paranthropus boisei in the early Pleistocene of East Africa
Thure E. Cerling,Emma Mbua,Francis Kirera,Fredrick K. Manthi,Frederick E. Grine,Meave G. Leakey,Matt Sponheimer,Kevin T. Uno +7 more
TL;DR: Stable isotopes are used to show that Paranthropus boisei had a diet that was dominated by C4 biomass such as grasses or sedges, which may indicate that the remarkable craniodental morphology of this taxon represents an adaptation for processing large quantities of low-quality vegetation rather than hard objects.
References
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Journal ArticleDOI
Revised calibration of the geomagnetic polarity timescale for the Late Cretaceous and Cenozoic
Steven C. Cande,Dennis V. Kent +1 more
TL;DR: An adjusted geomagnetic reversal chronology for the Late Cretaceous and Cenozoic is presented that is consistent with astrochronology in the Pleistocene and Pliocene and with a new timescale for the Mesozoic.
Book
The Structure of Evolutionary Theory
TL;DR: Defining and Revising the Structure of Evolutionary Theory and the Integration of Constraint and Adaptation in Ontogeny and Phylogeny: Historical Constraints and the Evolution of Development.
Journal ArticleDOI
Intercalibration of standards, absolute ages and uncertainties in 40Ar/39Ar dating
Paul R. Renne,Paul R. Renne,Carl C. Swisher,Alan L. Deino,Daniel B. Karner,Thomas L. Owens,Donald J. DePaolo +6 more
TL;DR: McDougall et al. as mentioned in this paper derived intercalibration factors for McClure Mountain hornblende (MMhb-1), GHC-305 biotite, GA-1550, Taylor Creek sanidine (TCs), relative to Fish Canyon sanidine(ACs), were derived from 797 analyses involving 11 separate irradiations with well-constrained neutronfluence variations.
Journal ArticleDOI
African climate change and faunal evolution during the Pliocene-Pleistocene
TL;DR: In this paper, the best dated and most complete African mammal fossil databases indicate African faunal assemblage and speciation changes during the Pliocene-Pleistocene interval (the last ca. 5.3 million years) were mediated by changes in African climate or shifts in climate variability.
Book
Macroevolution, pattern and process
TL;DR: In this article, the author argues that only "quantum speciation" (rapid and radically divergent) can explain the story of life revealed in the fossil record; macroevolution, he contends, cannot be attributed to microevolutionary forces such as mutation, genetic drift and natural selection.
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