Evolution of generalist pollination systems

不同的物种可以采取非常不同的策略来利用他们环境中的资源。生态专家使用的资源范围很窄，而多面手使用的资源范围很广。这些差异可能会对生态系统的稳定性产生重要影响，因为多面手对环境变化的适应能力更强。事实上，很容易想象，一种依靠单一种类的传粉者进行繁殖的植物比一种可以由许多物种授粉的物种更脆弱。从历史上看，授粉生物学家的注意力主要集中在专门化系统的研究上，也许是因为它们更壮观。一个经典的例子是达尔文的Angraecum Sesquipeale兰花和它被预测(并最终得到证实)的长鼻子授粉蛾。然而，越来越多的研究人员呼吁对多面手授粉系统进行进一步的研究，因为这些系统非常丰富，在植物进化中一直很重要。*本提案专门讨论了来自加勒比海群岛的苦瓜科植物群体中多面手授粉策略的机制和结果。我提出了三个短期目标。在第一个目标中，我将确定产生通才战略的过程。具体地说，我将测试多面手的进化成功是否是因为他们进化出了特性创新，使他们能够成功地由不同的传粉者授粉。这将包括研究传粉者的有效性，以及具有不同授粉策略的物种种群中的花形差异。*在第二个目标中，我将测试与通才策略相关的收敛形态性状的独立进化所涉及的分子机制是否涉及相同的基因或基因组区域。这将涉及不同来源的多面手的比较QTL定位以及比较转录研究。*最后，第三个目标将解决多面手系统的重要性。它将测试多面手是否比使用系统发育方法的专家拥有更高的多样化比率，以及海洋岛屿上物种的存在是否会影响这些比率。*这项提议有可能通过展示生态通才战略如何演变并通过量化其进化成功来极大地改变我们对生态通才战略的看法。

Different species can adopt very different strategies to use the resources in their environments. Ecological specialists use a narrow range of resources whereas generalists use a broad range. These differences can have important implications for the stability of ecosystems as generalists are more robust to environmental changes. Indeed, it is easy to conceive that a plant relying on a single species of pollinator for its reproduction will be more vulnerable than a species that can be pollinated by many species.******Historically, the attention of pollination biologists has been mostly directed towards the study of specialization systems, perhaps because they are more spectacular. One classic example is Darwin's Angraecum sesquipedale orchid and its predicted (and eventually confirmed) long proboscis pollinating moth. Yet, more and more researchers are calling for further studies on generalist systems as these are abundant and have been important in plant evolution.******This proposal addresses specifically the mechanisms and consequences of generalist pollination strategies in a plant group from the Caribbean Islands from the Gesneriaceae family. I propose three short-term objectives.******In the first objective, I will determine the processes that gave rise to generalist strategies. Specifically, I will test if the evolutionary success of generalists is due to the fact that they have evolved trait innovations that allows them to be successfully pollinated by different pollinators. This will consist in studying pollinator effectiveness, but also the floral shape variance in populations of species with contrasting pollination strategies.******In the second objective, I will test if the molecular mechanisms involved in the independent evolution of convergent morphological traits associated with generalist strategies involved the same genes or genome regions. This will involve comparative QTL mapping of generalists of different origins as well as comparative transcriptomic studies.******Finally, the third objective will address the significance of generalist systems. It will test if generalists have higher diversification rates than specialists using phylogenetic approaches, and if the presence of species on oceanic islands affect these rates. ******This proposal has the potential to drastically change the way we perceive ecological generalist strategies by showing how they evolve and by quantifying their evolutionary success.