Shifts in life-history traits as a response to cannibalism in larval long-toed salamanders (Ambystoma macrodactylum)

We examined the potential influence of cannibalism on life-history characte ristics of larval long-toed salamanders (Ambystoma macrodactylum). Using a 2 x 2 factorial design, crossing morphology with diet, we exposed typical m orph larvae to one of four types of stimulus animals: cannibal morphs fed a conspecific diet, cannibal morphs fed a heterospecific diet (i.e., Tubifex ), typical morphs fed a conspecific diet, and typical morphs fed a heterosp ecific diet. Test larvae exposed to stimulus animals fed a conspecific diet exhibited a slower growth rate and an increase in the time taken to reach metamorphosis. These changes in life history likely represent a cost of ant ipredator behavior.