The rapid dissolution of dioecy by experimental evolution

第一作者：Guillaume G. Cossard

第一单位：洛桑大学

通讯作者：John R. Pannell

 Abstract 

研究背景：Evolutionary transitions from hermaphroditism to dioecy have been common in flowering plants, but recent analysis also points to frequent reversions from dioecy to hermaphroditism.

主要发现：Here, we use experimental evolution to expose a mechanism for such reversions, validating an explanation for the scattered phylogenetic distribution of dioecy.

结果1-移除雄株，发现雌株雄化：We removed males from dioecious populations of the wind-pollinated plant Mercurialis annua and allowed natural selection to act on the remaining females that occasionally produced male flowers; such “leaky” sex expression is common in both males and females of dioecious plants.

结果2-性状可遗传：Over the course of four generations, females evolved a 23-fold increase in average male flower production. This phenotypic masculinization of females coincided with the evolution of partial self-fertilization, high average seed set in the continued absence of males, and a capacity to sire progeny when males were re-introduced into their populations.

结论1：Our study thus validates a mechanism for the rapid dissolution of dioecy and the evolution of functional hermaphroditism under conditions that may frequently occur during periods of low population density, repeated colonization, or range expansion.

结论2：Our results illustrate the power of natural selection, acting in replicated experimental populations, to bring about transitions in the mating behavior of plants.

 通讯作者 

**John R. Pannell**

doi: https://doi.org/10.1016/j.cub.2020.12.028

Journal: Current Biology

Published date: Jan 19, 2021