Squeezing out the last egg-annual fish increase reproductive efforts in response to a predation threat.

Both constitutive and inducible antipredator strategies are ubiquitous in nature and serve to maximize fitness under a predation threat. Inducible strategies may be favored over constitutive defenses depending on their relative cost and benefit and temporal variability in predator presence. In African temporary ponds, annual killifish of the genus are variably exposed to predators, depending on whether larger fish invade their habitat from nearby rivers during floods.