Resolving the phylogenetic placement of the chacma baboon (Papio ursinus griseipes) from central Mozambique using non-invasive genetic data

Baboons inhabiting Gorongosa National Park (GNP), central Mozambique, were originally classified as Papio ursinus griseipes based on their range south of the Zambezi River and early phylogeographic studies. Subsequent phenotypic assessments, however, revealed pronounced morphological variability, with individuals exhibiting diagnostic traits of yellow, Kinda, and gray-footed chacma baboons, complicating population assignment. Morphological and genetic data together with datasets from other taxa have been used to explore the origins of this variation, including testing hypotheses of admixture or hybridisation between yellow and chacma baboons. However, previous studies relied on limited sample sizes, likely underestimating the true extent of diversity. Here, we investigated variation in baboons from Central Mozambique within a comparative framework with the aim of clarifying their phylogenetic placement. We analysed over 250 non-invasive fecal samples collected in GNP and the nearby Catapú Forest Reserve (CFR), generating datasets for mitochondrial ( cyt b , 12S, and D-loop) and Y-linked (TSPY gene) markers, and used comparative datasets and multiple analytical approaches. Our results support previous classifications within mtDNA clade B1 but further indicate that the population constitutes a geographically distinct, and previously undescribed lineage within southern Africa. CFR appears to function as a contact zone, although the precise geographic origin or genetic proximity of the second lineage remains unresolved. We detected contrasting genetic assignments based on maternally ( P. u. griseipes ) versus paternally ( P. u. ursinus ) inherited markers, a pattern previously hypothesised for gray-footed chacma baboons. Together, our findings suggest the population at GNP and CFR holds undescribed variation and highlight the need for geographically extensive genetic surveys across Mozambique and neighbouring regions to fully characterise baboon diversity in southern Africa.