Fig. 4
From: Rival seminal fluid induces enhanced sperm motility in a polyandrous ant
Comparison between the effects of own seminal fluid, a rival male’s seminal fluid, a virgin queen’s reproductive tract fluid, and a mixture of equal volumes of the same rival male’s seminal fluid and queen’s reproductive tract fluid on sperm motility parameters in natural ejaculates of A. echinatior males. (a) A higher proportion of spermatozoa were active when in contact either with rival male seminal fluid, queen reproductive tract fluid or a 50/50% mixture of rival male seminal fluid and queen reproductive fluid, as compared to sperm only exposed to own seminal fluid (F1,142 = 71.98, P < 0.0001), but all these treatments were equally effective in activating spermatozoa. These similar increases in sperm motility were also reflected by increases in (b) sperm velocity (F1,142 = 31.54, P < 0.0001) and (c) sperm linearity (F1,142 = 7.79, P = 0.0060). Bars are means ± SE and levels not connected by the same letter were significantly different in post-hoc Student’s t tests