An international team of researchers has used mitochondrial DNA (mtDNA) to help distinguish between a group of Madagascar Mouse Lemurs who have recently begun to diverge.
One of the issues associated with delineating species that have recently diverged from common ancestors is that often there has not been sufficient time for the usual cues of speciation, such as morphological differences, reproductive isolation, and monophyly within the gene tree to have become settled and readily evident. Writing in the online journal, PLoS One, seven scientists from the United States, Germany, and Madagascar used multiple lines of evidence from mtDNA and nuclear DNA (nDNA) to identify “cryptically diverged” population-level mouse lemur lineages from throughout Madagascar. It is believed to represent the most thorough sample of mouse lemur species ever conducted.
The result was the identification of a large number of geographically-defined clades. These were strongly supported by the initial mtDNA evidence, as well as additionally supported by nDNA patterns. The clades thus identified, are also supported by population divergence estimates based on genealogical exclusivity estimates. The paper concludes that “Mouse lemur lineage diversity is reflected in both a geographically fine-scaled pattern of population divergence within established and geographically widespread taxa, as well as newly resolved patterns of micro-endemism revealed through expanded field sampling into previously poorly and well-sampled regions.”
For more information, please see the original article at the following URL: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0009883