Yohannes Haile-Selassie: "The Paleobiology, Paleoecology and Biogeography of the Earliest Australopithecus: New insights from Woranso-Mille, Ethiopia"

Talk link: https://youtu.be/044ZkbKthYM

Talk abstract: Australopithecus anamensis, mostly known from 4.2–3.9 million-years-old deposits in Ethiopia and Kenya, is the earliest representative of the genus. This species marks a major adaptive shift and a new course in human evolutionary history. However, due to the paucity of its remains in the fossil record, its paleobiology, paleoecology and biogeography are still poorly understood, as are its phylogenetic relationships and first and last appearances in the fossil record. Recent discovery of a complete 3.8 million-years-old cranium of the species from Woranso-Mille, a Pliocene site in the Afar region of Ethiopia, provided a better understanding of its craniofacial morphology and redefined its temporal range. The discovery also expanded the species’ spatial range by 130 Km further north from its previously known northern extent at Asa Issie in the Middle Awash (Ethiopia). Slightly younger deposits at Woranso-Mille (3.5–3.33 Ma) have also yielded hominin fossils representing species that are unknown in other eastern African sites of contemporaneous age. While A. anamensis is the best candidate to be the ancestor of A. afarensis, populations of A. anamensis at Woranso-Mille may also have locally given rise to species such as A. deyiremeda. This and other reasons highlight the significance of A. anamensis in human evolutionary history, while they make Woranso-Mille one of the most important Pliocene sites in Africa.