Encephalization, adaptation and evolution of chiroptera: A statistical analysis with further evidence for bat monophyly

As part of a large-scale study on brain morphometrics and adaptations in ma mmals, we addressed the problem of chiropteran evolution. A specific statis tical framework was designed to test which of two competing hypotheses (bat monophyly vs, diphyly) is more strongly supported by quantitative brain da ta. Our analyses, based on 120 species, revealed that megabats and microbat s were more closely related to each other than to primates, and illustrated the convergent adaptations of the brain of bats to similar trophic (i.e, f eeding related) niches. Ecologically-corrected characters were then used to derive a new phylogeny which also supports the chiropteran clade. The mono phyletic origin of bats is the preferred hypothesis to explain brain quanti tative evolution in chiropterans and primates.