The adaptive value of gluttony: predators mediate the life history trade-offs of satiation threshold.

摘要: Animals vary greatly in their tendency to consume large meals. Yet, whether or how meal size influences fitness wild populations is infrequently considered. Using a predator exclusion, mark–recapture experiment, we estimated selection on the amount of food accepted during an ad libitum feeding bout (hereafter termed ‘satiation threshold’) wolf spider Schizocosa ocreata. Individually marked, size-matched females known satiation threshold were assigned exclusion and inclusion treatments tracked for 40-day period. We also narrow-sense heritability using dam-on-female-offspring regression. In absence predation, high was positively associated with larger faster egg case production. However, these selective advantages lost when predators present. be 0.56. Taken together, our results suggest that can respond begets life history trade-off this system: individuals tend produce cases but suffer increased susceptibility predation.