How does mass extinction affect species that survive?

there are no surviving species if a mass extinction occurs.

they will soon become extinct.

they combine gene pools.

they fill new roles in the changed environment.

When there is a mass extinction, species that survive will combine gene pools. A gene pool is the sum of population of same species have the same genetic material. Those species that survived will combine for them to survive from extinction. If there is a combination of gene pool then there will be a possibility that evolution will happen

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