Mutations are the raw material on which evolution acts, and knowledge of their frequency and genomic distribution is crucial for understanding how evolution operates at both long and shoPedigree based and phylogeneticrt timescales. Using high-coverage linked-read sequencing for a focal quartet of gray mouse lemurs (Microcebus murinus), we estimated the mutation rate to be among the highest calculated for a mammal at 1.52 × 10–8 (95% credible interval: 1.28 × 10−8–1.78 × 10−8) mutations/site/generation. These comparisons revealed general consistency of the mutation spectrum between the pedigree-based and the substitution-rate analyses.

Pedigree-based and phylogenetic methods support surprising patterns of mutation rate and spectrum in the gray mouse lemur

Here, we attempt to understand how the dynamic process of landscape change on Madagascar has shaped the distribution of a targeted clade of mouse lemurs (genus Microcebus) and, conversely, how phylogenetic and population genetic patterns in these small primates can reciprocally advance our understanding of Madagascar's prehuman environment. By examining patterns of both inter- and intraspecific genetic diversity in mouse lemur species found in the eastern, western, and Central Highland zones, we conclude that the natural environment of the Central Highlands would have been mosaic, consisting of a matrix of wooded savanna that formed a transitional zone between the extremes of humid eastern and dry western forest types.

Geogenetic patterns in mouse lemurs (genus Microcebus) reveal the ghosts of Madagascar's forests past

As is true of virtually every realm of the biological sciences, our understanding of speciation is increasingly informed by the genomic revolution of the past decade. Technologies ranging from restriction-site associated DNA sequencing (RADseq), to whole genome sequencing and assembly, to transcriptomics, to CRISPR are revolutionizing the means by which investigators can both frame and test hypotheses of lineage diversification. We propose that a unified theory of speciation will take into account the idiosyncratic features of genomic architecture examined in the light of each organism’s biology and ecology drawn from across the full breadth of the Tree of Life.

What is speciation genomics? The roles of ecology, gene flow, and genomic architecture in the formation of species