Predator-induced Predator-induced polyphenisms allow the species to develop in a more reproductively-successful way in a predator's absence, but to otherwise assume a more defensible morphology. However, this can fail if the predator evolves to stop producing the kairomone to which the prey responds. For example, the fly larvae that feed on Daphnia cucullata (a water flea) release a kairomone that Daphnia can detect. When the fly larvae are present, Daphnia grow large helmets that protect them from being eaten. However, when the predator is absent, Daphnia have smaller heads and are therefore more agile swimmers.
Predator-induced Predator-induced polyphenisms allow the species to develop in a more reproductively-successful way in a predator's absence, but to otherwise assume a more defensible morphology. However, this can fail if the predator evolves to stop producing the kairomone to which the prey responds. For example, the midge larvae (Chaoborus) that feed on Daphnia cucullata (a water flea) release a kairomone that Daphnia can detect. When the midge larvae are present, Daphnia grow large helmets that protect them from being eaten. However, when the predator is absent, Daphnia have smaller heads and are therefore more agile swimmers.
R
fly larvae
midge larvae (Chaoborus)
R
fly
midge