Dissertation Research: Fitness Consequences of Floral Nectar Production Rate for the Hummingbird-Pollinated Plant Ipomopsis aggregata

花蜜是被子植物最常见的花卉奖赏方式，但鲜为人知的是花蜜产出率对授粉成功的影响。这项研究将集中在蜂鸟授粉的单果植物Ipomopsis ggregata的这种关系上。这项研究的主要问题涉及产蜜率对适合度的总体影响：1)产蜜率较高的植物授粉成功吗？初步的田间证据表明，这种现象确实存在(至少在雄性功能授粉成功的情况下是如此)，因此研究这种效应的原因机制将是有益的。这个问题的答案是：2)NPR如何影响现存量作物？3)现存量作物如何影响访花行为？4)访花行为如何影响授粉成功？这项研究将通过各种相辅相成的方法来研究这些问题，包括计算机模拟，观察自然变异对NPR的影响，以及田间和鸟场的操纵实验。对隔离中每种机制的效果的估计可以结合在一起，以产生授粉成功的估计，该估计可以与问题1中的基准值进行比较，以检验所提出的机制的充分性。这项研究不仅将增进对NPR变异的适合性后果的理解，还将加深对这种影响可能表达的机制的理解。

Nectar is the most common floral reward produced by angiosperms, but little is known about the effect of nectar production rate on pollination success. This investigation will focus on this relationship for the hummingbird-pollinated monacarpic plant Ipomopsis aggregata. The primary question of the study involves the overall effect of nectar production rate on fitness: 1) Do plants with higher nectar production rates have greater pollination success? Preliminary field evidence indicates that this does occur (at least for male function pollination success), so study of the causal mechanisms of this effect will be profitable. This question will answered by: 2) How does NPR affect standing crop? 3) How does standing crop affect visitation behavior? 4) How does visitation behavior affect pollination success? The study will investigate these questions with a variety of mutually reinforcing approaches, including computer simulation, observation of the effects of natural variation in NPR, and manipulative experiments in the field and aviary. Estimates of the effect of each mechanism in isolation can be combined to produce an estimate of pollination success that can be compared with benchmark values from Question 1, testing the adequacy of the mechanisms proposed. The research will increase understanding, not only of the fitness consequences of variation in NPR, but the mechanisms through which such effects may be expressed.