Blackwell Publishing

Sex: lower extinction rate


Asexual reproduction has a peculiar taxonomic distribution. It is mainly confined to small twigs in the phylogenetic tree: it is typically found in an odd species such as the dandelion, or perhaps a whole genus, within a larger taxonomic group that mainly reproduces sexually; only very rarely is it found throughout a larger phylogenetic group. The only exceptions are a suborder of rotifers (the Bdelloidea) and of gastrotrichs (Chaetonoidea); all the former, and most of the latter, are believed to be asexual.

The spindly taxonomic distribution of asexual reproduction suggests that asexual lineages have a higher extinction rate than sexual lineages - that asexual lineages usually do not last long enough to diversify into a genus or higher taxonomic level.

Is this a group selectionist account of the advantage of sexual reproduction, or not?

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