We report the presence of Homo at 2.78 and 2.59 million years ago and Australopithecus at 2.63 million years ago. Although the Australopithecus specimens cannot yet be identified to species level, their morphology differs from A. afarensis and Australopithecus garhi. These specimens suggest that Australopithecus and early Homo co-existed as two non-robust lineages in the Afar Region before 2.5 million years ago, and that the hominin fossil record is more diverse than previously known. Accordingly, there were as many as four hominin lineages living in eastern Africa between 3.0 and 2.5 million years ago: early Homo1, Paranthropus2, A. garhi3, and the newly discovered Ledi-Geraru Australopithecus.
https://www.nature.com/articles/s41586-025-09390-4
The presence of both early Homo and Australopithecus at Ledi-Geraru has implications for hominin taxonomy and diversity in this region in the 3.0–2.0 million year interval. Despite the relative paucity of fossils discovered in this time interval, evidence for multiple non-robust lineages in eastern and southern Africa indicates that taxonomic diversity had already evolved by 2.5 Ma. Here we examine taxonomic and phylogenetic hypotheses for the newly discovered hominin specimens from Ledi-Geraru.
First, although the Asboli sample contains only two molars (Table 1), and they predate Homo specimens A.L. 666-1 and MLP-1549 by more than 150,000 years, we regard the most parsimonious hypothesis to be that these are members of the same species of Homo30. The existence of Homo at Ledi-Geraru by around 2.78 Ma was previously established by the LD 350-1 mandible1; the new dental material from the Asboli area, as well as the LD 302-23 premolar described here from the Gurumaha sedimentary package, provide additional evidence of Homo prior to 2.5 Ma.
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