eLife assessment
This important study uses the brain endocast of a ~1.9-million-year-old hominin fossil from Kenya, attributed to genus Homo, to show that the organization of the Broca's area in members of early Homo was primitive. Specifically, the prefrontal sulcal pattern in this early Homo specimen more closely resembles that of chimpanzees than of modern humans. Because Broca's area is associated with speech function, the compelling evidence from this study is relevant for understanding the timing and trajectory of evolution of speech related traits in our genus. Coupled with its potential implications for taxonomic classification, this study will be of interest to paleoanthropologists, paleontologists, archaeologists, and neuroscientists.