Question

Why large number of eggs are layed by animals where fertilization is external?

Answer 1

ensuring having less chance of survive still remain a few to survive

Answer 2

Organisms exhibiting external fertilisation releases more number of gametes into the surrounding to increase the chance of fertilisation. Because the fertilisation is external there is less possibility of fusion of gametes in the outside environment and if somehow fertilisation carried out successfully there will be chances that the externally fertilised eggs and young ones are at greater risk from predators. So, to ensure the chances of survival, these organisms releases large number of gametes to the surrounding.

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