Meeting Abstract
S8.2-3 Monday, Jan. 6 11:30 Developmental plasticity in amphibians: mechanisms, adaptations and constraints CRESPI, Erica J; Washington State Univ. erica.crespi@wsu.edu
It is well known that environmental conditions during early life stages can alter specific developmental processes that influence phenotypic expression and performance throughout the life of an animal. Fluctuating levels of environment-responsive hormones, such as glucocorticoids, often mediate alterations in developmental processes throughout an organism that have both short- and long-term effects on phenotypic expression. What is less understood is whether hormone-mediated developmental plasticity is adaptive, maladaptive or neutral in its effects on fitness, and even less is known about how this form of developmental plasticity influences phenotypic evolution. Hormone-mediated developmental plasticity may accelerate evolutionary responses to environmental change by increasing phenotypic variation in traits associated with fitness, but it may also restrict phenotypic expression or the ability to adaptively respond to environmental changes experienced later in life, thus, constraining evolutionary dynamics. Amphibians provide an excellent model system in which to study the evolutionary impacts of hormone-mediated developmental plasticity because their biphasic life cycle emphasizes the importance of considering the effects of environmental variability in different life history stages and there is a large literature describing the ecology and population dynamics associated with developmental plasticity. There also is an increasing understanding of how hormone-mediated developmental plasticity is related to post-metamorphic morphology, behavior, physiology, and fitness in amphibians. This knowledge allows for the inclusion of indirect environmental effects in evolutionary models to better predict how populations will respond to selection caused by climate change or other environmental perturbations currently threatening populations.
