Multiple bursts of speciation in Madagascar’s endangered lemurs

Lemurs are often cited as an example of adaptive radiation, as more than 100extant species have evolved and ï¬ lled ecological niches on Madagascar.However, recent work suggests that lemurs lack a hallmark of other adaptiveradiations: explosive speciation rates that decline over time. Thus, character-izing the tempo and mode of evolution in lemurs can reveal alternative waysthat hyperdiverse clades arise over time, which might differ from traditionalmodels. We explore lemur evolution using a phylogenomic dataset with broadtaxonomic sampling that includes the lorisiforms of Asia and continentalAfrica. Our analyses reveal multiple bursts of diversiï¬ cation (without sub-sequentdeclines)thatexplainmuchoftoday’s lemur diversity. We also ï¬ ndhigher rates of speciation in Madagascar’slemurscomparedtolorisiforms,and we demonstrate that the lemur clades with high diversiï¬ cation rates alsohave high rates of genomic introgression. This suggests that hybridization inthese primates is not an evolutionary dead-end, but potential fuel for diver-siï¬ cation. Considering the conservation crisis affecting strepsirrhine primates,with approximately 95% of species threatened with extinction, this study offersa perspective for explaining Madagascar’s primate diversity and reveals pat-terns of speciation, extinction, and gene flow that will help inform futureconservation decisions