Meeting Abstract
Models of population dynamics have been used to infer the impacts of climate change on the distributions of species. The predictions of these models depend greatly on parameters that characterize the studied organisms as well as the environment. In widespread group of lizards (Sceloporus undulatus complex), behavioral thermoregulation buffers environmental extremes that would otherwise decrease performance. However, embryos do not have the capacity for thermoregulation as well as mobile life-stages, and therefore at greater risk under climate change when extreme events will become more frequent. Based on lethal temperatures of embryos and highly resolved projections of past and future climates, we modeled how (1) incorporating embryonic survival in population models will affect populations’ fitness predictions and (2) how oviposition decisions and reproductive period may shift to avoid exposure to environmental extremes under climate change. Ignoring either environmental extremes or their impact on embryonic survival causes one to overestimate population growth rates and underestimate the impacts of climate change. Although lizards can extend their reproductive period in future climates, rate of embryonic survival will decrease at many locations. Accurate predictions will require detailed knowledge of environmental conditions and thermal tolerances at each stage of the life cycle.
