Question

Why do frog and fish lay a large number of egg each time?

Answer 1

Basically, smaller organisms produce more offsprings as a response to shorter lifespans and/or greater death rates.

Female frogs lay a lot of eggs but not all of these eggs get fertilzed by male frogs. Remember that frogs follow external fertilization.

Answer 2

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Though fish and frogs lay hundreds of eggs all the eggs do not get fertilized and develop into new individuals.

This is because the eggs get exposed to water movement, wind and rainfall. Also, there are other animals in the pond which may feed on eggs.

Thus, production of large number of eggs is necessary to ensure fertilization of at least a few of them.

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