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SEX-RATIO BIAS WITH ASYMMETRIC EXCHANGE OF POLLEN BETWEEN DEMES
1Department of Mathematics and Statistics, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
Abstract:
In a patch of hermaphroditic plants, with a low level of pollen migration between patches, a prevailing wind creates a gradient, within the patch, in the strength of local competition among pollen for reproductive success. This leads to a sex ratio gradient, with a male (pollen) bias in downwind individuals, which can be quite strong even for large patches. The effect can be understood as follows: downwind individuals have relatively low reproductive value and respond by putting more resources into the gamete (pollen) with the best long-range (extra-patch) reproductive success.
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