Overview

• A Nature paper published August 13 reports 13 teeth from Ledi-Geraru dated to 2.6–2.8 million years ago via volcanic ash and argon analyses
• Dental morphology assigns some teeth to early Homo and others to an Australopithecus lineage distinct from A. afarensis
• The coexistence of these hominins in northeastern Ethiopia supports a branching, ‘bushy’ model of human evolution rather than a simple linear progression
• Researchers have withheld naming the new Australopithecus species because teeth alone lack the cranial or postcranial evidence required for formal classification
• Ongoing work combines tooth-enamel chemistry and expanded field excavations to clarify the diets and ecological interactions of these overlapping hominin lineages