“Including fossils in phylogenetic climate reconstructions: a deep time perspective on the climatic niche evolution and diversification of spiny lizards (Sceloporus)”

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A. Michelle Lawing, P. David Polly, Diana K. Hews, and Emília P. Martins

Fossils and other paleontological information improve phylogenetic comparative method estimates of phenotypic evolution

Fossils improve estimates of phenotypic evolution

A desert spiny lizard (Sceloporus magister) chows down on a moth in Washington County, Utah.
(Photo © Jay K Goldberg, Keche Photography)

Including fossils and other paleontological information in phylogenetic comparative methods improves estimates of phenotypic evolution. In a new article appearing in The American Naturalist, the authors investigate the spatiotemporal climate setting in which a diverse group of species evolved by combing fossil evidence, paleoclimate models, phylogenetic comparative methods, and physiological models of extinction risk. They produce a spatiotemporal model of suitable climate for spiny lizards, genus Sceloporus, from the Miocene to the Pleistocene of North America. They demonstrate that in several cases, fossils are required for the reasonable estimation of past climatic niches. By projecting physiological models of extinction risk onto models of past climate, the authors can determine where it would have been intolerable for spiny lizards to live during the Miocene, Pliocene, and Pleistocene. The number of hours lizards had to avoid heat is positively correlated with extinction risk, and probably prevented spiny lizards from inhabiting Mexico until the climate cooled enough to provide suitable habitat, around six million years ago. Currently, Mexico has the highest diversity in and richness of spiny lizards. However, it will no longer provide suitable habitat to most spiny lizard species if climate change raises temperatures to past levels. This paper highlights the three-way interaction of physiological, geographic, and climatic spaces. Read the Article