Ambystoma maculatum larvae evolve to recognize local predator cues


Meeting Abstract

113.2  Monday, Jan. 7  Ambystoma maculatum larvae evolve to recognize local predator cues RACK, JM; Univ. of Connecticut jessica.rack@uconn.edu

In an aquatic environment where visual cues are limited, prey animals often respond to predator-released chemical cues with changes in behavior, morphology, or life history traits. Assuming sufficient additive genetic variation, natural selection should act to improve the prey population’s recognition of local predator populations. Across a geographic landscape of varying selection pressures, prey and predator populations could evolve altered recognition systems or cues, respectively. If predators respond to prey evolution, then we might expect a coevolutionary arms race. Alternatively, prey might retain generalized cue recognition systems and predators might differ little in their cue chemistries, creating more predictable predator-prey interactions. I performed an experiment to determine if prey behavior differed in response to local predator chemical cues versus cues from a geographically distant population of the same predator species. Larvae of the spotted salamander, Ambystoma maculatum, were presented with predator cues isolated from two species of amphibian predator (marbled salamander larvae, Ambystoma opacum and red-spotted newts, Notophthalmus viridescens) collected from ponds stratified by distance from a focal population. I found that larval Ambystoma maculatum took more time to move in response to cues from local predatory newts, suggesting a recognition and avoidance mechanism based on adaptation to local predators. Rearing condition of the larvae (raised in the presence or absence of predator chemical cues) also affected prey behavior, suggesting that experience is a factor in such interactions. These results provide evidence for higher relative fitness in the prey animal’s home environment, and support the hypothesis that prey can evolve to recognize the specific chemical cues released by the local predator population.

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