bioRxiv preprint doi: https://doi.org/10.1101/019075; this version posted May 7, 2015. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Bayesian Inference of Divergence Times and Feeding Evolution in Grey Mullets (Mugilidae) Francesco Santini1, Michael R. May1, Giorgio Carnevale2, and Brian R. Moore1,∗ 1Department of Evolution and Ecology, University of California, Davis, Davis, CA, U.S.A. 2Dipartimento di Scienze della Terra, Universita degli Studi di Torino, Torino, Italy ∗E-mail:
[email protected] Abstract Grey mullets (Mugilidae, Ovalentariae) are coastal fishes found in near-shore environments of tropical, subtropical, and temperate regions within marine, brackish, and freshwater habitats throughout the world. This group is noteworthy both for the highly conserved morphology of its members—which complicates species identification and delimitation—and also for the uncommon herbivorous or detritivorous diet of most mullets. In this study, we first attempt to identify the number of mullet species, and then—for the resulting species—estimate a densely sampled time-calibrated phylogeny using three mitochondrial gene regions and three fossil calibrations. Our results identify two major subgroups of mullets that diverged in the Paleocene/Early Eocene, followed by an Eocene/Oligocene radiation across both tropical and subtropical habitats. We use this phylogeny to explore the evolution of feeding preference in mullets, which indicates multiple independent origins of both herbivorous and detritivorous diets within this group. We also explore correlations between feeding preference and other variables, including body size, habitat (marine, brackish, or freshwater), and geographic distribution (tropical, subtropical, or temperate).