The absence of the AMELY gene suggests a potential female classification for the analyzed sample; however, this conclusion remains uncertain. The challenge lies in the difficulty of accurately identifying proteins from such ancient samples. Additionally, some male individuals, including at least one Neanderthal, have been found to possess genetic deletions that entirely remove this gene.
Another significant factor is the variation found at 425 amino acid locations, which differ across hominin species and even among individuals of the genus Paranthropus. This variation could serve as a means to better understand the relationships both between and within these species and to clarify ongoing debates regarding the number of Paranthropus species and their connection to other hominins. While the limited number of four samples restricts definitive conclusions, researchers have uncovered some intriguing insights.
The study sought to determine whether the amino acid variations present in the samples could be expected among individuals of the same species. By comparing four randomly selected human genomes, they examined the level of variation in those cases. Their analysis indicated that such variability among randomly chosen individuals was “plausible.” Nonetheless, given that the modern human population is probably more extensive than that of Paranthropus, the results are not conclusive.
Among the 425 amino acids, 16 exhibited species-specific distinctions across different hominins. Surprisingly, the analysis revealed that Paranthropus robustus is the closest relative to our genus, Homo, according to a phylogenetic tree constructed from these variations. Nonetheless, the researchers caution that the data remains insufficient to draw firm conclusions.
This does highlight an “isn’t enough data yet” situation. The paper comes from the work of Enrico Cappellini, a regular contributor to Ars Technica and the senior author on the study, who also holds a faculty position at the University of Copenhagen’s Globe Institute. A review of his faculty profile indicates that advancing techniques for examining ancient samples is his primary research focus. This offers hope for expanding our understanding of extinct hominin species as more data is collected in the future. A significant challenge mentioned in the study is that the technique used requires the destruction of a small portion of the unique samples, which are invaluable fragments of human history.
Science, 2025. DOI: 10.1126/science.adt9539 (About DOIs).
