Delay in development in the embryos of some fishes during periods of unfavourable environment conditions is called a. Diapause b. Aestivation c. Hibernation d. None of these
Option A. diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions. It is a physiological state with very specific initiating and inhibiting conditions. The mechanism is a means of surviving predictable, unfavorable environmental conditions, such as temperature extremes, drought, or reduced food availability. Diapause is observed in all the life stages of arthropods, especially insects. Embryonic diapause, a somewhat similar phenomenon, occurs in over 130 species of mammals, possibly even in humans,and in the embryos of many of the oviparous species of fish in the order Cyprinodontiformes.
