Allocation to reproductive mode (sexual and asexual) can vary depending on environmental conditions but is often examined at the population level, whereas selection acts upon the individual. We examined individual variation in reproductive mode to identify how the interaction of sex and the environment affect population genetic diversity. Using the plant Marchantia inflexa, we tested whether reproductive allocation pattern varies consistently between males and females and among plants collected from different environments, and determined if morphological responses were the result of individual plasticity or genetic differences. We then quantified genetic variability between the different environments and between the sexes. Male and female plants were collected from two strikingly different habitats within the same region: along natural sites (rivers) and along novel human-modified sites (roadsides). Using a common garden approach, we found a strong sex by habitat interaction: male and female responses differed significantly by their source habitat. For females, relative to river-collected, road-collected plants had higher growth and asexual reproduction, while the pattern was reversed, although not significant, for males. Genetic differentiation was significant between the two habitats with no evidence of individual differences in plasticity for growth, but there was a genotype effect for asexual propagule production. Males and females did not differ genetically; but river-collected plants with lower sexual potential were more diverse than roadside-collected plants, possibly the result of founder events. These results show that individual variation in reproduction is controlled by the interaction of both the environment and genetics. Due to different selection pressures between natural and novel habitats, there are observable differences in life history traits with an associated evolutionary response to the novel habitat.
|Number of pages||15|
|State||Published - Mar 2014|
Bibliographical noteFunding Information:
Acknowledgments The authors thank the Wildlife Section of the Forestry Division of the Republic of Trinidad and Tobago for collection and export permits, and Water and Sewage Authority for access to Quare River and North Oropuche River. We also thank D. Westneat and D. Wetzel for statistical advice, P. Crowley and C. Stieha for editorial comments, and Department of Plant and Soil Sciences at the University of Kentucky for greenhouse space. Funding was provided by a Research Postdoctoral Fellowship from the University of Kentucky awarded to J.R.B.
- Allelic diversity
- Evolutionary response
- Life history
- Marchantia inflexa
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics