====== 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 : [[https://en.wikipedia.org/wiki/Evolution_of_sexual_reproduction|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.

A 2024 study from the University of Oregon found that distinct male/female chromosome differences in animals goes back at least 480 million years. ([[https://www.biorxiv.org/content/10.1101/2024.02.21.581452v3.full.pdf|ref.]])

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:[[http://phys.org/news/2015-05-population-benefits-sexual-males.html|phys.org]]LINK-BROKEN__

There are, however, many organisms that have maintained extensively successful populations over millions of years apparently entirely asexually. See [[https://en.wikipedia.org/wiki/Asexual_reproduction#Examples_in_animals|Wikipedia]]

~~stars>3/5~~