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Biology subjects

Hart, J. A.

Publications and source records attributed to Hart, J. A..

2 recordsLinked to original sources

Targeted Chromosomal Sequencing of Wild Bonobos Identifies a Genetically Distinct Subpopulation East of the Lomami River

Bonobos (Pan paniscus), an endangered species, have for decades been genetically understudied, partly due to difficulties in obtaining high-quality samples. The study of their genome is important not only for understanding their evolution, but also for improving conservation efforts, including population management, diversity and inbreeding assessment, and tracking rescued individuals to combat illegal wildlife trafficking. Here, we use chromosome 21 target capture data from 156 non-invasively collected faecal samples from wild bonobos to perform a comprehensive analysis of their population structure. We confirm the existence of three previously suggested subpopulations identified here as Western, Central and Eastern bonobos which are defined by natural barriers of gene flow such as the Lomami River. By estimating levels of inbreeding, diversity and differentiation, we find support for isolation of mainly Western and Eastern populations and add information on the dispersal routes of their ancestors. We infer split times and separation of these populations and apply a genetic framework to geolocalize samples of unknown origin, showing that locations of their potential origin can be estimated with a precision of up to a median of [~]50 km. Our study provides valuable insight into the evolution and population structure of bonobos and reveals how rivers act as strong barriers between populations. It also offers resources for conservation efforts and highlights the need to monitor bonobo populations more closely, in particular isolated ones. ImpactBonobos have been difficult to study genetically due to their remote forest habitat and endangered status. Here we used non-invasive sampling and chromosome 21 target capture sequencing to perform the most detailed analysis to date of their population structure. We find three main subpopulations and genetic differentiation influenced by river barriers, especially with populations found on the Eastern side of the Lomami river. This data will be useful for identifying the geographic origin of confiscated samples and thus aid bonobo conservation efforts.

bioinformatics↗

Breaking the rule: An exceptional Y chromosome introgression between deeply divergent primate species

Hybridization between distinct lineages is widespread in nature, with important implications for adaptation and speciation. If hybrids are fertile, alleles can introgress across species boundaries. Hybrid fitness is often sex dependent, with heterogametic hybrids showing lower fitness than homogametic individuals, a phenomenon known as Haldanes rule. Consequently, loci inherited strictly through the heterogametic sex rarely introgress. We focus on the Y-chromosomal history of guenons (tribe Cercopithecini), a group of African primates that hybridized extensively throughout their evolutionary history. Although our inferences suggest that Haldanes rule is generally in place, we uncover a remarkable Y chromosome introgression event from Cercopithecus mitis into C. denti, which occurred ca. six million years after their initial divergence. Only a weak signal of autosomal gene flow is present, suggesting that the introgressing Y chromosome reached fixation in C. denti from a very low initial frequency. We use simulations to explore the evolutionary mechanisms at play, and find that selection is needed to achieve fixation of the novel Y chromosome. We identify a number of fixed protein differences between the introgressed and ancestral Y, with meiotic drive being an alternative mechanism to adaptive introgression. Our results show that the ability to produce viable and fertile heterogametic hybrids persisted for six million years in guenons, providing a remarkable exception to Haldanes rule.

evolutionary biology↗