Surprisingly little is known about body-size evolution within the most diverse amphibian order, anurans (frogs and toads), despite known effects of body size on the physiological, ecological, and life-history traits of animals more generally. Here we examined anuran body-size evolution among 2434 species with over 200 million years of shared evolutionary history. We found clade-specific evolutionary shifts to new body-size optima along with numerous independent transitions to gigantic and miniature body sizes, despite the upper limits of anuran body size remaining quite consistent throughout the fossil record. We found a weak, positive correlation between a species’ body size and maximum latitude and elevation, including a dearth of small species at higher elevations and broader latitudinal and elevational ranges in larger anurans. Although we found modest differences in mean anuran body size among microhabitats, there was extensive overlap in the range of body sizes across microhabitats. Finally, we found that larger anurans are more likely to consume vertebrate prey than smaller anurans are, and that species with a free-swimming larval phase during development are larger on average than those in which development into a froglet occurs within the egg. Overall, anuran body size does not conform to geographic and ecological patterns observed in other tetrapods but is perhaps more notable for variation in body size within geographic regions, ecologies, and life-histories. Here we document this variation and propose target clades for detailed studies aimed at disentangling how and why variation in body size was generated and is maintained in anurans.

All data was collected from the literature and sources are cited in the data table. Data types without references in the data table are all from single sources that are stated in the publication's methods. 

Data types without references in the data table are all from single sources that are stated in the publication's methods.