Evolutionary history of two cryptic species of northern African jerboas

BMC Evolutionary Biology

article

Moutinho, Ana Filipa¹  Brito, José Carlos²  Boratyński, Zbyszek²  Serén, Nina²  Paupério, Joana²  Silva, Teresa Luísa²  Martínez-Freiría, Fernando²  Sotelo, Graciela²  Faria, Rui²  Mappes, Tapio⁴  Alves, Paulo Célio² 

[1] Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Biology;CIBIO-InBIO Associate Laboratory, Research Centre in Biodiversity and Genetic Resources, University of Porto;Department of Biology, Faculty of Science, University of Porto;Division of Ecology and Evolutionary Biology, Department of Biological and Environmental Science, University of Jyväskylä;Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho

关键词: African jerboas;    Cryptic diversity;    Demographic history;    Deserts;    Jaculus;    Local adaptation;    Phylogenetics;    Reproductive isolation;    Sahara-Sahel;    Speciation;   

DOI  :  10.1186/s12862-020-1592-z

学科分类：护理学

来源: BioMed Central

【 摘 要 】

Climatic variation and geologic change both play significant roles in shaping species distributions, thus affecting their evolutionary history. In Sahara-Sahel, climatic oscillations shifted the desert extent during the Pliocene-Pleistocene interval, triggering the diversification of several species. Here, we investigated how these biogeographical and ecological events have shaped patterns of genetic diversity and divergence in African Jerboas, desert specialist rodents. We focused on two sister and cryptic species, Jaculus jaculus and J. hirtipes, where we (1) evaluated their genetic differentiation, (2) reconstructed their evolutionary and demographic history; (3) tested the level of gene flow between them, and (4) assessed their ecological niche divergence. The analyses based on 231 individuals sampled throughout North Africa, 8 sequence fragments (one mitochondrial and seven single copy nuclear DNA, including two candidate genes for fur coloration: MC1R and Agouti), 6 microsatellite markers and ecological modelling revealed: (1) two distinct genetic lineages with overlapping distributions, in agreement with their classification as different species, J. jaculus and J. hirtipes, with (2) low levels of gene flow and strong species divergence, (3) high haplotypic diversity without evident geographic structure within species, and (4) a low level of large-scale ecological divergence between the two taxa, suggesting species micro-habitat specialization. Overall, our results suggest a speciation event that occurred during the Pliocene-Pleistocene transition. The contemporary distribution of genetic variation suggests ongoing population expansions. Despite the largely overlapping distributions at a macrogeographic scale, our genetic results suggest that the two species remain reproductively isolated, as only negligible levels of gene flow were observed. The overlapping ecological preferences at a macro-geographic scale and the ecological divergence at the micro-habitat scale suggest that local adaptation may have played a crucial role in the speciation process of these species.

【 授权许可】

CC BY|CC0