Jordan Crispin Y
Department of Zoology, University of British Columbia, 2370-6270 University Blvd. Vancouver, B.C., V6T 1Z4, Canada.
Theor Popul Biol. 2015 Feb;99:7-17. doi: 10.1016/j.tpb.2014.10.005. Epub 2014 Nov 11.
Floral displays are functionally and genetically integrated structures, so modifications to display will likely affect multiple fitness components (pleiotropy), including pollen export and self-pollination, and therefore selfing rate. Consequently, the great diversities of floral displays and of mating systems found among angiosperms have likely co-evolved. I extend previous models of mating system evolution to determine how pleiotropy that links viability (e.g., probability of survival to reproduction) and the allocation of pollen for export and selfing affects the evolution of selfing, outcrossing, and in particular, mixed mating. I show that the outcome depends on how pollen shifts from being exported, unused, or used for selfing. Furthermore, pleiotropy that affects viability can explain observations not addressed by previous theory, including the evolution of mixed mating despite high inbreeding depression in the absence of pollen-limitation. Therefore, pleiotropy may play a key role in explaining selfing rates for such species that exhibit otherwise enigmatic mating systems.
花的展示是功能和基因整合的结构，所以对展示的改变可能会影响多个适合度成分（多效性），包括花粉输出和自花授粉，进而影响自交率。因此，被子植物中发现的花展示和交配系统的巨大多样性可能是共同进化的。我扩展了之前的交配系统进化模型，以确定连接生存能力（例如，存活到繁殖的概率）以及用于输出和自花授粉的花粉分配的多效性如何影响自交、异交，特别是混合交配的进化。我表明结果取决于花粉如何从输出、未使用或用于自花授粉中转变。此外，影响生存能力的多效性可以解释先前理论未涉及的观察结果，包括在没有花粉限制的情况下尽管存在高近亲衰退但混合交配的进化。因此，多效性可能在解释具有其他神秘交配系统的此类物种的自交率方面发挥关键作用。
