PARENT SESSION
Contributed Oral Session 61: Evolutionary Ecology: Aquatic Systems
Tuesday, August 9, 1:30 PM - 5:00 PM, Meeting Room 518 A, Level 5, Palais des congrès de Montréal
Rate of adaptation to new environments in Trinidadian guppies.
Gordon, Swanne*,1, Hendry, Andrew 1, Reznick, David2, 1 McGill University, Montreal, Quebec, Canada2 University of California-Riverside, Riverside, California, U.S.
ABSTRACT- Many organism are experiencing environmental change. If they are to persist as viable populations, they will need to alter their geographic distribution (i.e. migrate to more benign environments) or adapt to in situ changes. I am using Trinidadian guppies to examine the rate at which fitness evolves in the wild, as it is this composite rate that will determine whether or not a population can persist in the face of environmental change. Eight years ago a successful introduction of guppies was performed from high predation sites in the Yarra River to low predation sites in the Damier River, which previously lacked guppies. The Damier now has guppies that inhabit both high and low predation environments and have been able to adapt to those environments for about 8 years: i.e. 13-26 generations. For my initial work on this system, I have characterized the current degree of adaptive divergence between high and low predation Damier fish in relation to the Yarra fish, and quantified the selective environment in the Damier. Preliminary results have shown that the high predation Damier fish have significantly lower survival than the low predation fish (p< 0.001), and they produce more, smaller embryos (p< 0.01). These results mirror prior research which have shown that the contrast in predation regime in the rivers have led to the evolution of a suite of differences in guppy morphology, behaviour and life history.
Key words: Adaptation, Trinidadian guppies, Life-history evolution, Predation