Thosteman, Hanna
- Lunds Universitet
Sammanfattning
The extraordinary diversity of flowering plants has long captivated biologists and evolutionary ecologists. Plant-insect relationships are recognized as a major driver of this diversity, with pollinators playing a crucial role in angiosperm speciation and trait diversification. Numerous observational and experimental studies have shown that pollinators influence the evolution of floral traits—such as size, shape, color, and scent—through their preferences and selective pressures. While much of our understanding of plant phenotypic diversification stems from specialized systems, most plants participate in more generalized interactions. This bias has created a significant gap in our knowledge of how phenotypes diversify in relation to pollinator communities in more generalized species. In this thesis, I investigate the drivers of intraspecific variation in floral scent and morphology within Arabis alpina, a pollination-generalist species. Through a series of experiments, I examine the interplay between floral traits, pollinator communities, and environmental factors to understand how mainly floral scent, but also plant-pollinator traitmatching, evolves across the species range. In Chapter I, I found that while floral scent shares biosynthetic links with other phytochemical traits, it may evolve independently under pollinator-mediated selection. Chapter II demonstrated that floral scent emission is consistent across various conditions, despite significant differences in scent composition and pollinator community between neighboring populations. Chapter III revealed that almost all insect visitors contribute effectively to pollination, and have variable levels of morphological trait-matching, suggesting they could influence floral trait evolution. In Chapter IV, I showed that pollinators consistently preferred local over foreign flowers, indicating a possible mechanism for the observed geographic variation in scent composition. Collectively, these findings suggest that floral scent variation in A. alpina is shaped by pollinator-mediated selection, potentially as a locally adapted trait. This work contributes to the growing understanding of how floral scent as well as other floral traits evolve in pollination-generalist species, emphasizing its significance in generalized plant-insect interactions.
Nyckelord
Arabis alpina; Floral scent; Floral scent diversity; Generalist phenotypes; Intraspecific variation; Phenotypic evolution; Phenotypic integration; Plant-pollinator trait-matching; Pollinator community; spatial and temporal variations
Publicerad i
Utgivare: Lund University
SLU författare
UKÄ forskningsämne
Evolutionsbiologi
Ekologi
Publikationens identifierare
- ISBN: 978-91-8104-183-5
- eISBN: 978-91-8104-184-2
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/143602