Multiple dimensions of floral rewards drive pollinator behavior and pollen movement

Animal pollinated plants produce a diversity of rewards to attract pollinating insects. Most commonly these are nutritional rewards; either pollen (primarily protein and lipids) and/or nectar (primarily carbohydrates) in varying combinations and qualities. This reward strategy varies inter- and intraspecifically, but surprisingly little is known about how this variation impacts pollinator behavior and plant fitness. Additionally, plants that rely on bees for pollination face a challenge: attracting pollinators while minimizing pollen consumption. Bees provision larvae with pollen, and pollen consumption can reduce male fitness. In this dissertation I show that variation in complex plant reward strategy can impact pollinator foraging behavior and that perhaps these reward strategies might be important in shaping pollen movement among co-flowering plants. In chapter one, I show that bees' collection of pollen depends on both colony need and the amount of nectar offered by flowers. In chapter 2 I show that aversive alkaloids in pollen come with an ecological cost for plants via lost visitation, but that these costs can be overcome by taking an alternate reward strategy: offering high quality nectar. In chapter three I investigate interactions between reward strategy and patterns of conspecific and heterospecific pollen transfer in the wild, showing that plants with similar reward strategies are more likely to share pollen with each other, and that plants with high quality pollen receive less heterospecific pollen transfer. Together these three chapters highlight that floral rewards do not act in isolation, but rather pollen and nectar interactively shape pollinator behavior and can potentially impact plant fitness.

Level thesis:degree_level

Doctorate Degree

Year dc:date.issued

2020

Author dc:creator

• Francis, Jacob Samuel

Advisor dc:contributor.advisor

• Leonard, Anne S.

Committee members dc:contributor.committeemember

• Forister, Matthew L
• Leger, Elizabeth A
• Pravosudov, Vladimir V
• Parchman, Thomas L

• Behavioral Ecology
• Bumblebees
• Nutritional Ecology
• Pollen
• Pollination
• Social Insect

Statement dc:rights

• Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 United States

Handle dc:identifier.uri

http://hdl.handle.net/11714/7593

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/7593