Cryptic Patterns of Speciation in Cryptic Primates: Microendemic Mouse Lemurs and the Multispecies Coalescent.

Journal Article (Journal Article)

Mouse lemurs (Microcebus) are a radiation of morphologically cryptic primates distributed throughout Madagascar for which the number of recognized species has exploded in the past two decades. This taxonomic revision has prompted understandable concern that there has been substantial oversplitting in the mouse lemur clade. Here, we investigate mouse lemur diversity in a region in northeastern Madagascar with high levels of microendemism and predicted habitat loss. We analyzed RADseq data with multispecies coalescent (MSC) species delimitation methods for two pairs of sister lineages that include three named species and an undescribed lineage previously identified to have divergent mtDNA. Marked differences in effective population sizes, levels of gene flow, patterns of isolation-by-distance, and species delimitation results were found among the two pairs of lineages. Whereas all tests support the recognition of the presently undescribed lineage as a separate species, the species-level distinction of two previously described species, M. mittermeieri and M. lehilahytsara is not supported-a result that is particularly striking when using the genealogical discordance index (gdi). Nonsister lineages occur sympatrically in two of the localities sampled for this study, despite an estimated divergence time of less than 1 Ma. This suggests rapid evolution of reproductive isolation in the focal lineages and in the mouse lemur clade generally. The divergence time estimates reported here are based on the MSC calibrated with pedigree-based mutation rates and are considerably more recent than previously published fossil-calibrated relaxed-clock estimates. We discuss the possible explanations for this discrepancy, noting that there are theoretical justifications for preferring the MSC estimates in this case. [Cryptic species; effective population size; microendemism; multispecies coalescent; speciation; species delimitation.].

Full Text

Duke Authors

Cited Authors

  • Poelstra, JW; Salmona, J; Tiley, GP; Schüßler, D; Blanco, MB; Andriambeloson, JB; Bouchez, O; Campbell, CR; Etter, PD; Hohenlohe, PA; Hunnicutt, KE; Iribar, A; Johnson, EA; Kappeler, PM; Larsen, PA; Manzi, S; Ralison, JM; Randrianambinina, B; Rasoloarison, RM; Rasolofoson, DW; Stahlke, AR; Weisrock, DW; Williams, RC; Chikhi, L; Louis, EE; Radespiel, U; Yoder, AD

Published Date

  • February 2021

Published In

Volume / Issue

  • 70 / 2

Start / End Page

  • 203 - 218

PubMed ID

  • 32642760

Electronic International Standard Serial Number (EISSN)

  • 1076-836X

International Standard Serial Number (ISSN)

  • 1063-5157

Digital Object Identifier (DOI)

  • 10.1093/sysbio/syaa053

Language

  • eng