Page "Polymorphism (biology)" Paragraph 51

Of the many issues involved, there is widespread agreement on the following: the advantage of sexual and hermaphroditic reproduction over asexual reproduction lies in the way recombination increases the genetic diversity of the ensuing population .< sup > p234 </ sup >< sup > ch7 </ sup > The advantage of sexual reproduction over hermaphroditic is not clear.

In forms that have two separate sexes, same sex combinations are excluded from mating which decreases the amount of diversity compared with hermaphrodites by at least twice.

So, why are almost all progressive species bi-sexual, considering the asexual process is more efficient and simple, whilst hermaphrodites produce a more diversified progeny?

It has been suggested that differentiation into two sexes has evolutionary advantages allowing changes to concentrate in the male part of the population and at the same time preserving the existing genotype distribution in the females.

This enables the population to better meet the challenges of infection, parasitism, predation and other hazards of the varied environment.

( See also Evolution of sex.