Expert: Walter Hintz - 3/19/2008

Question
Why do plants and animals that live in the water have a simpler
reproductive process than the plants and animals that live on land?


Why are many kinds of fish very easily produced in fish hatcheries?


Answer
First question
 It has to do with fertilization.  All fertilization requires a liquid environment.  Aquatic animals with the exception of mammals use water as the medium to carry sperms to eggs.  This was a problem when animals evolved to land and was solved with internal fertilization methods. It is necessary for the sperms to be deposited into the female body. This is more complicated then releasing them into the water.

second question
 They are raised in tanks and not subject to predation by other  fishes