Question

why do fish and frogs lay eggs in thousands

Answer 1

because in external fertilisation the egs can deatroy so thats why ....

Answer 2

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Though fishes 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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