Open Access Senior Thesis
Bachelor of Arts
© 2018 Emma Berkele
Reproduction is essential for all organisms. In plants, reproduction relies on pollination. In addition to large-scale traits such as shape and color, flowers may use traits imperceptible to the naked eye in order to attract pollinators. One such trait may be conical cell shape of petal cells. Previous work has identified conical petal cells as providing a foothold for foraging bees, suggesting that conical cell shape is an adaptation to bee pollination. However, this hypothesis has not been fully tested and requires development of a rigorous methodology for quantifying cell shape. Here, we utilize natural variation in pollinator mode in pairs of Mimulus species to explore this hypothesis. We further developed a systematic and more robust methodology for measuring cell shape, Conical Value, C. We confirmed our C value in two wild-type Mimulus species and their flat-celled mutants. C also aligns more closely to qualitative observations than previously established metrics. Finally, we applied C to pairs of Mimulus species and found that petal cells were significantly more conical in bee-pollinated than self-pollinated species. Our findings suggest that pollination by bees either maintains or selects for petal cells with a conical shape.
Bekele, Emma, "Linking Petal Cell Shape to Pollinator Mode in Mimulus" (2019). Scripps Senior Theses. 1233.