Data from: Evidence for a mid-Jurassic adaptive radiation in mammals

A series of spectacular discoveries have transformed our understanding of Mesozoic mammals in recent years. These finds reveal hitherto-unsuspected ecomorphological diversity that suggests that mammals experienced a major adaptive radiation during the Middle to Late Jurassic. Patterns of mammalian macroevolution must be reinterpreted in light of these new discoveries, but only taxonomic diversity and limited aspects of morphological disparity have been quantified. We assess rates of morphological evolution and temporal patterns of disparity using large datasets of discrete characters. Rates of morphological evolution were significantly elevated prior to the Late Jurassic, with a pronounced peak occurring during the Early to Middle Jurassic. This intense burst of phenotypic innovation coincided with a stepwise increase in apparent long-term standing diversity and the attainment of maximum disparity, supporting a “short-fuse” model of early mammalian diversification. Rates then declined sharply, and remained significantly low until the end of the Mesozoic, even among therians. This supports the “long-fuse” model of diversification in Mesozoic therians. Our findings demonstrate that sustained morphological innovation in Triassic stem-group mammals culminated in a global adaptive radiation of crown-group members during the Early to Middle Jurassic.

Usage Notes
Analysis R Code and Full ResultsR scripts and input data for all analyses performed in study, including full output files.Dryad Supplementary Figures for Close et al. Elevated morphological rates and high disparity support a mid-Jurassic adaptive radiation in mammalsDryad supplementary figures, including captions.Close_et_al_Current_Biology_Mesozoic_Mammals_BEAST2BEAST 2 XML file for the morphological-clock/tip-dating analysis conducted using the Zhou et al. (2013) Mesozoic mammal matrix.