Experimental evolution reveals that sperm competition intensity selects for longer, more costly sperm.

ABSTRACT: It is the differences between sperm and eggs that fundamentally underpin the differences between the sexes within reproduction. For males, it is theorized that widespread sperm competition leads to selection for investment in sperm numbers, achieved by minimizing sperm size within limited resources for spermatogenesis in the testis. Here, we empirically examine how sperm competition shapes sperm size, after more than 77 generations of experimental selection of replicate lines under either high or low sperm competition intensities in the promiscuous flour beetle Tribolium castaneum. After this experimental evolution, populations had diverged significantly in their sperm competitiveness, with sperm in ejaculates from males evolving under high sperm competition intensities gaining 20%

SUBMITTER: Godwin JL 

PROVIDER: S-EPMC6089504 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature