Relationship of pollination ecology to population genetic structure and speciation rates in Justicia (Acanthaceae)

不同的传粉剂在花粉携带和覆盖距离方面的不同行为预计会导致种群之间不同程度的基因流动。这将导致不同授粉综合征种群之间种群遗传结构的差异，最终导致物种分化或灭绝率的差异。然而，这一假设从未得到有效的检验。在这项拟议的研究中，授粉、种群遗传结构、多样化比率这三个假定因果链的全部三个环节将首次被一起检验。被选中的研究群体是新大陆Justica，这是一个由蜜蜂和蜂鸟授粉的代表组成的单系群体。用染色的花粉对3个喜蜜性和3个嗜热性的物种进行授粉实验，以检验花粉流动差异的假说。为了验证种群遗传结构差异的假说，将对三个嗜蜜性物种和三个嗜毛虫物种进行分子分析。随后，将进行基于序列的新大陆木麻黄属系统发育分析，以检验具有不同授粉综合征的姊妹支系一致分化多样化速率的假说。

Divergent behaviour of different pollinating agents in terms of pollen carry-over and distances covered is expected to result in different degrees of gene flow between populations. This would then lead to differences in population genetic structure between populations with different pollination syndromes, and ultimately in divergent speciation or extinction rates. This hypothesis, however, has never been effectively tested.In the proposed study, all three links of the presumed causal chain ¿ pollination, population genetic structure, diversification rates ¿ will for the first time be examined together. The chosen study group is New World Justicia, a monophyletic group containing bee and hummingbird pollinated representatives. Pollination experiments with dyed pollen will be conducted on three melittophilous and three trochilophilous species to test the hypothesis of differences in pollen flow. A molecular analysis of three melittophilous and three trochilophilous species will be conducted to test the hypothesis of differences in population genetic structure. Subsequently, a sequence-based phylogenetic analysis of New World Justicia will be conducted to test the hypothesis of consistently divergent diversification rates in sister clades with different pollination syndromes.