Increased Floral Rewards due to Local Adaptation Drives Plant Ecological Speciation via Learned Preferences of Pollinators
Increased Floral Rewards due to Local Adaptation Drives Plant Ecological Speciation via Learned Preferences of Pollinators
复制标题
DOI：
10.1086/721764
复制
发表时间：
2022-07
期刊：
影响因子：
--
通讯作者：
G. Takimoto;Kotaro Kagawa;Takeaki Satow;T. Sakamoto
中科院分区：
文献类型：
--
作者：
G. Takimoto;Kotaro Kagawa;Takeaki Satow;T. Sakamoto
在动物授粉的植物中，生长环境和授粉环境是自然选择的两个重要因素。然而，它们对植物物种形成的同时影响仍有待探索。在这里，我们报告了一个理论发现，如果植物对生长环境的局部适应增加了它们对传粉者的花奖励，它可以强烈地促进植物的生态物种形成。我们认为两个不断发展的植物性状，营养和花的信号性状，在一个群体遗传模型的两个植物种群的不同选择，从不同的生长环境。植物的营养特性决定了植物对当地环境的适应性。适应当地的植物比不适应的植物更能回报传粉者。通过联想学习，传粉者获得学习偏好花的信号特征表达更好的奖励植物。如果传粉者的学习偏好在种群之间变得不同，则会发生花信号分歧，并且植物会在营养和花信号性状之间产生遗传关联，从而通过双等位基因机制导致生态物种形成。有趣的是，物种形成取决于新的花信号变体是否在植物种群局部适应生长环境之前或之后出现。我们的研究结果表明，同时选择生长和授粉环境可能是重要的动物授粉植物的生态物种。
In animal-pollinated plants, the growth environment and pollination environment are two important agents of natural selection. However, their simultaneous effects on plant speciation remain underexplored. Here, we report a theoretical finding that if plants’ local adaptation to the growth environment increases their floral rewards for pollinators, it can strongly facilitate ecological speciation in plants. We consider two evolving plant traits, vegetative and floral signal traits, in a population genetic model for two plant populations under divergent selection from different growth environments. The vegetative trait determines plants’ local adaptation. Locally adapted plants reward pollinators better than maladapted plants. By associative learning, pollinators acquire learned preferences for floral signal traits expressed by better-rewarding plants. If pollinators’ learned preferences become divergent between populations, floral signal divergence occurs and plants develop genetic associations between vegetative and floral signal traits, leading to ecological speciation via a two-allele mechanism. Interestingly, speciation is contingent on whether novel floral signal variants arise before or after plant populations become locally adapted to the growth environment. Our results suggest that simultaneous selection from growth and pollination environments might be important for the ecological speciation of animal-pollinated plants.