Some groups of animals are inordinately speciose. A prime example are the microhylid frogs of New Guinea and its satellite islands -- with over 300 species, one of the largest subfamilies of frogs in the world. What causes this explosion of biodiversity? These frogs have long been hypothesized to be part of an adaptive radiation with specializations suggested for burrowing, terrestrial, semi-aquatic, arboreal, and scansorial lifestyles.

We studied hypotheses of the “niche” in this group for the first time by exploring the connection between environment (microhabitat) and the correlated evolution in morphology and performance using phylogenetic comparative analysis of data collected in the field from 24 species.

We also conducted a large-scale phylogenetic study including over 175 species with 3 nuclear and 2 mitochondrial markers to establish the evolutionary history of their diversification.

We have furthermore started a detailed morphological and biomechanical analysis, including microCT for a jumping and swimming specialist to understand their design features. We find that locomotor specialization explains a good deal of diversification in this group, but we discuss additional axes of ecological diversification that may be at play to explain such high degrees of syntopy.

We gratefully acknowledge financial support from NSF DEB 1145733.

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