Affiliation: | 1. Department of Biological Sciences, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, New York 12180;2. Odum School of Ecology, University of Georgia, Athens, Georgia 30602;3. Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131;4. Department of Integrative Biology, Oregon State University, Corvallis, Oregon 97331;5. Department of Biology, University of San Diego, San Diego, California 92110;6. Marine Science Institute, University of California, Santa Barbara, California 93106;7. Museum of Vertebrate Zoology, University of California, Berkeley, California 94720;8. School of Life Sciences, Arizona State University, Tempe, Arizona 85287;9. Department of Biological Sciences, Southeastern Louisiana University, Hammond, Louisiana 70402;10. Department of Natural Resource Ecology and Management, Oklahoma State University, Stillwater, Oklahoma 74078;11. Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104;12. Department of Forestry & Natural Resources, Purdue University, West Lafayette, Indiana 47907;13. Department of Biology, Florida State University, Tallahassee, Florida 32306;14. School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588;15. Department of Biology, Tennessee Technological University, Cookeville, Tennessee 38505;16. Department of Forestry, University of Kentucky, Lexington, Kentucky 40546;17. Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211;18. College of Biological Sciences, University of California‐Davis, Davis, California 95616 |
Abstract: | Environmental variation favors the evolution of phenotypic plasticity. For many species, we understand the costs and benefits of different phenotypes, but we lack a broad understanding of how plastic traits evolve across large clades. Using identical experiments conducted across North America, we examined prey responses to predator cues. We quantified five life‐history traits and the magnitude of their plasticity for 23 amphibian species/populations (spanning three families and five genera) when exposed to no cues, crushed‐egg cues, and predatory crayfish cues. Embryonic responses varied considerably among species and phylogenetic signal was common among the traits, whereas phylogenetic signal was rare for trait plasticities. Among trait‐evolution models, the Ornstein–Uhlenbeck (OU) model provided the best fit or was essentially tied with Brownian motion. Using the best fitting model, evolutionary rates for plasticities were higher than traits for three life‐history traits and lower for two. These data suggest that the evolution of life‐history traits in amphibian embryos is more constrained by a species’ position in the phylogeny than is the evolution of life history plasticities. The fact that an OU model of trait evolution was often a good fit to patterns of trait variation may indicate adaptive optima for traits and their plasticities. |