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Title: Pollen competition is the mechanism underlying a variety of evolutionary phenomena in dioecious plants
Summary It has long been known that more pollen grains often arrive on stigmas than there are ovules to fertilize, resulting in pollen competition. Moreover, this competition among pollen grains (gametophytes) depends, in part, on their extensive haploid gene expression. Here I review how this leads to a variety of phenomena in dioecious plants of interest to evolutionary biologists. For example, pollen competition can lead to extreme female‐biased sex ratios. In addition, gene expression by individual pollen grains can slow mutation accumulation and degeneration of the Y chromosome. Lastly, I review work on how the haploid selection resulting from pollen competition has been proposed to influence which alleles are linked to the Y chromosome, and some recent empirical evidence in support of this theory.  more » « less
Award ID(s):
1753629
PAR ID:
10459835
Author(s) / Creator(s):
 
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
224
Issue:
3
ISSN:
0028-646X
Page Range / eLocation ID:
p. 1075-1079
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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