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Killikaike blakei is a new genus and species of anthropoid from the late Early Miocene of southeastern Argentina based on the most pristine fossil platyrrhine skull and dentition known so far. It is part of the New World platyrrhine clade (Family Cebidae; Subfamily Cebinae) including modern squirrel (Saimiri) and capuchin monkeys (Cebus) and their fossil relatives known from Early to Middle Miocene and subrecent periods. Living cebines are relatively large-brained, adroit predatory foragers and live within complex social groups, and wild capuchins exhibit a wide range of behaviors associated with enhanced intelligence. We show that K. blakei lacks diagnostic derived characteristics of the lower face and premolar dentition that are shared by modern cebines, but its strongly vaulted frontal bone and capacious anterior cranial fossa indicate the early evolution of an enlarged forebrain. Miocene | Paleoprimatology | Patagonia | Platyrrhini | Cebinae

Evidence has overcome the conventional wisdom that the hominins were restricted to Africa until 800,000 years ago. The study shows that hominin dispersals from Africa in the earliest Pleistocene correlated with the appearance of hominins typically referred to as 'Homo erectus' who carried with them an Oldowan tool technology.

The uniquely preserved range of fossil found in the ancient lake beds of the lower part of the Yixian Formation, Liaoning Province, northeastern China have provided new information on bird-dinosaur relationships, the early diversification of birds and the origin and evolution of flowering plants. Estimates of the geological age have varied between the Late Jurassic and Early Cretaceous. A dating study suggests that the lower Yixian fossil horizons are middle Early Cretaceous.

The first known fossil ape from the early-middle Miocene of Fejej, Ethiopia, is described here. The specimen, FJ-18SB-68, is a partial ulna from a locality dated by 40Ar/39Ar and paleomagnetic methods to a minimum age of 16.18 MYA. Compared to a variety of extant and fossil ulnae, FJ-18SB-68 is most similar to Turkanapithecus, Proconsul, and Pliopithecus, and appears to have been an arboreal quadruped with substantial forearm rotational mobility. Among the extant ulnae, canonical variates analysis successfully discriminates platyrrhines from catarrhines and within the latter, cercopithecoids from hominoids. Basal catarrhines (e.g., Aegyptopithecus) are platyrrhine-like in their morphology. Two basic trends appear to evolve from this generalized template: one with less mobile and more habitually pronated forearms, as seen in living and fossil cercopithecoids (including Victoriapithecus and Paracolobus), and another with greater forearm rotational mobility in fossil and modern hominoids. Primitive Miocene apes, including Proconsul, Turkanapithecus, and FJ-18SB-68, share with extant hominoids a more laterally positioned and laterally facing radial notch and an incipient trochlear keel. This morphology, along with a large insertion area for m. brachialis, suggests a departure from the more habitually pronated hand posture of monkeys and may indicate greater climbing abilities in these arboreally quadrupedal apes. Later Miocene apes, such as Oreopithecus and Dryopithecus share additional morphological features with hominoids, indicating considerable suspensory and climbing capabilities. KEY WORDS fossil apes; anthropoids; postcranium; forelimb; Turkanapithecus; Pliopithecus; multivariate analysis

For more than 70 years, red sandstones of the Gobi Desert have yielded abundant articulated skeletons of Late Cretaceous dinosaurs, lizards, and mammals. At Ukhaa Tolgod, structureless sandstones are the only fossiliferous facies, and we present new evidence for deposition on dune-sand-sourced alluvial fans that were built at the margins of stabilized eolian bedforms during mesic climatic episodes. In laterally and vertically adjacent large-scale eolian cross-strata in which skeletons are absent, we have found abundant tracks of dinosaurs that walked on sparsely vegetated dunes that were active under xeric conditions. Our study of calcareous concretions in vaguely bedded eolian sandstones suggests that bedding was nearly destroyed by burrowing invertebrates and trampling dinosaurs. The accumulation of illuvial clays and pedogenic calcite in these sediments reduced infiltration of rainwater and, with attendant climatic change and heavy rainfall events, led to fan development.

The Deseadan or South American Land Mammal Age no longer represents the first occurrence of rodents and primates in South America, because of the unanticipated discovery in Central Chilean Andes of the continent's first rodent, which belongs to a new fossil mammal fauna. The discovery provides information crucial to understanding the source area and primitive morphology of South American caviomorphs. The co-occurrence of several higher-level taxa, normally confined to older or younger intervals, establishes this fauna as representing a new biochronological interval even before the Deseadan.

Buried glacier ice that is 8.1 million years old has been discovered in Beacon valley, East Antarctica. There are two views about the Antarctic climate during Pliocene. One view holds that East Antarctica was largely free of glacier ice during Pliocene. The latest discovery is in support of the other view which maintains that a stable polar ice sheet developed by the middle Miocene which has persisted since then. Dating of the ice has been done by laser-fusion 40Ar/39Ar analysis of volcanic ash in the thin, overlying glacial till.

The identity of the first hominid species to disperse out of Africa and the timing of this dispersal remain highly controversial. The earliest known hominid fossils in Europe and Asia [...], Archaeological excavations at the site of Dmanisi in the Republic of Georgia have uncovered two partial early Pleistocene hominid crania. The new fossils consist of a relatively complete cranium and a second relatively complete calvaria from the same site and stratigraphic unit that yielded a hominid mandible in 1991. In contrast with the uncertain taxonomic affinity of the mandible, the new fossils are comparable in size and morphology with Homo ergaster from Koobi Fora, Kenya. Paleontological archaeological, geochronological and paleomagnetic data from Dmanisi all indicate an earliest Pleistocene age of about 1.7 million years ago, supporting correlation of the new specimens with the Koobi Fora fossils. The Dmanisi fossils, in contrast with Pleistocene hominids from Western Europe and Eastern Asia, show clear African affinity and may represent the species that first migrated out of Africa.