Floral signals evolve in a predictable way under artificial and pollinator selection in Brassica rapa
Author(s)
Zu, Pengjuan; Schiestl, Florian P.; Gervasi, Daniel; Li, Xin; Runcie, Daniel; Guillaume, Frédéric; ... Show more Show less
Download12862_2020_Article_1692.pdf (691.3Kb)
Publisher with Creative Commons License
Publisher with Creative Commons License
Creative Commons Attribution
Terms of use
Metadata
Show full item recordAbstract
Background
Angiosperms employ an astonishing variety of visual and olfactory floral signals that are generally thought to evolve under natural selection. Those morphological and chemical traits can form highly correlated sets of traits. It is not always clear which of these are used by pollinators as primary targets of selection and which would be indirectly selected by being linked to those primary targets. Quantitative genetics tools for predicting multiple traits response to selection have been developed since long and have advanced our understanding of evolution of genetically correlated traits in various biological systems. We use these tools to predict the evolutionary trajectories of floral traits and understand the selection pressures acting on them.
Results
We used data from an artificial selection and a pollinator (bumblebee, hoverfly) evolution experiment with fast cycling Brassica rapa plants to predict evolutionary changes of 12 floral volatiles and 4 morphological floral traits in response to selection. Using the observed selection gradients and the genetic variance-covariance matrix (G-matrix) of the traits, we showed that the observed responses of most floral traits including volatiles were predicted in the right direction in both artificial- and bumblebee-selection experiment. Genetic covariance had a mix of constraining and facilitating effects on evolutionary responses. We further revealed that G-matrices also evolved in the selection processes.
Conclusions
Overall, our integrative study shows that floral signals, especially volatiles, evolve under selection in a mostly predictable way, at least during short term evolution. Evolutionary constraints stemming from genetic covariance affected traits evolutionary trajectories and thus it is important to include genetic covariance for predicting the evolutionary changes of a comprehensive suite of traits. Other processes such as resource limitation and selfing also need to be considered for a better understanding of floral trait evolution.
Date issued
2020-09Department
Massachusetts Institute of Technology. Department of Civil and Environmental EngineeringJournal
BMC Evolutionary Biology
Publisher
Springer Science and Business Media LLC
Citation
Zu, Pengjuan et al. "Floral signals evolve in a predictable way under artificial and pollinator selection in Brassica rapa." BMC Evolutionary Biology 20, 1 (September 2020): 127 © 2020 The Author(s)
Version: Final published version
ISSN
1471-2148