Journal
EVOLUTION
Volume 63, Issue 12, Pages 3114-3123Publisher
WILEY-BLACKWELL
DOI: 10.1111/j.1558-5646.2009.00784.x
Keywords
Botryllus schlosseri; diffusion; advection model; fertilization distance; paternity; sex allocation
Categories
Funding
- National Science Foundation [OCE-04-35749, OCE-04-25088]
Ask authors/readers for more resources
Male gain curves describe the relationship between allocation to sperm production and male reproductive success and are central to models of sex allocation in hermaphrodites. Sperm competition is expected to result in more linear gains and select for increased allocation. We hypothesized that high sperm production in passively mating systems may also be the result of selection to enhance the ability to fertilize distant ova. Consequently, we explored the effect of distance on male gain curves in a free-spawning colonial ascidian. The performance of focal males that varied in sperm production was assayed at three distances via microsatellite markers. An advection-diffusion model was used to estimate sperm concentration gradients, to predict male reproductive gain integrated across multiple downstream females, and explore effects of hydrodynamic conditions. As distance increased, male reproductive success decreased and empirical gain curves became increasingly linear. Our model predicted that the expected net gain curve is relatively insensitive to variation in flow regime and will saturate much more slowly than if only a single, nearby distance is considered. Thus, high levels of sperm production may enhance fitness both in competitive situations and with increasing fertilization distance, highlighting the need to consider distance effects when evaluating gain curves.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available