Sexual reproduction

The maintenance of sexual reproduction in a highly competitive world has long been one of the major mysteries of biology given that asexual reproduction can reproduce much more quickly as 50% of offspring in sexual reproduction are males, unable to produce offspring themselves."

Source : Wikipedia

Put another way, from an evolutionary perspective, sexual reproduction would need to provide an advantage of more than 50% to be maintained as viable in the long term.

Several theories have been proposed. A 2015 hypothesis (from the University of East Anglia, UK) suggests that :

In the absence of sex, populations accumulate deleterious mutations through a ratcheting effect where each new mutation takes a population closer to extinction. Sexual selection helps to remove those mutations, enabling populations to persist against the threat of extinction."

Source : BROKEN-LINK:phys.org LINK-BROKEN

There are, however, many organisms that have maintained extensively successful populations over millions of years apparently entirely asexually. See Wikipedia

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