THE MAINTENANCE OF SPERM VARIABILITY: CONTEXT-DEPENDENT SELECTION ON SPERM MORPHOLOGY IN A BROADCAST SPAWNING INVERTEBRATE

摘要: Why are sperm so variable despite having a singular, critical function and an intimate relationship with fitness? A key to understanding the evolution of morphology is identifying which traits enable be successful fertilizers. Several (e.g., tail length, overall size) implicated in performance, but benefits these likely highly context dependent. Here, we examined phenotypic selection on broadcast spawning tube worm (Galeolaria gemineoa). We conducted laboratory experiments measure between average relative fertilization success across range environments that were designed approximate concentrations ages encountered by eggs nature. found strength form multivariate varied substantially our environmental gradients. Sperm long tails small heads favored high-concentration environments, whereas at low old ages. suggest variation local environment resulting differences can preserve variability both within among males.