Why was it important for organisms to reproduce sexually rather than asexually?

Answer 1

It shuffles and reshuffles genes in each generation, much like a person shuffling a deck of cards. Most prokaryotes reproduce asexually, and most eukaryotes reproduce sexually.

Answer 2

Sexual reproduction allows for genetic variation through the combination of genes from two individuals, increasing the likelihood of adaptation to changing environments. This genetic diversity helps populations evolve and survive in the face of selection pressures such as diseases and other threats.