The early environment experienced by organisms can have significant phenotypic effects that persist throughout life. Parents, mothers in particular, commonly determine these early environments. Maternal effects, or the influence of maternal phenotypes on offspring phenotypes, are therefore likely ubiquitous in natural populations. However, the frequency and evolutionary consequences of maternal effects are largely unknown.
Here I show that maternal phenotypes can have large effects on offspring morphology, fecundity, and behavior. I theoretically explore the potential for these effects to resolve the long-standing "lek paradox" in the field of sexual selection. I also empirically investigate these effects in the heliconia bug, Leptoscelis tricolor.
Females heliconia bugs lay eggs on several species of heliconia plants in Panama and Costa Rica. Host plant species choice by mothers largely determines the natal environment that offspring will experience due to the limited mobility of juveniles. Insects that emerged on one species of heliconia, Heliconia platystachys, were larger, and males expressed relatively larger secondary-sexual traits for their body size than those raised on H. mariae. The mating probability and fecundity of female offspring was higher on H. platystachys. Furthermore, males raised on H. platystachys performed a faster rate of copulatory courtship while mating and also boosted this rate when mating with females from H. platystachys. Such copulatory movements may enhance male and female reproductive success.
While host plant species choice by mothers had significant maternal effects on offspring overall, the consequences for offspring varied with time. Mothers that laid eggs on H. platystachys early in the wet season produced large, fecund offspring in good phenotypic condition. This maternal effect gradually changed until, later in the season, sons and daughters raised on H. platystachys were smaller and daughters laid few or no eggs and did not mate. Thus, at some times H. platystachys appeared to be a much superior host plant for offspring, while at other times, H. mariae was better. Dynamic consequences of maternal behaviors (here, host plant species choice) for offspring have only rarely been explored and may have far-reaching consequences for the evolution of maternal and offspring traits.
|Advisor:||Emlen, Douglas J.|
|Commitee:||Christy, John H., Greene, Erick P., Maron, John L., Martin, Thomas E., Mousseau, Timothy A.|
|School:||University of Montana|
|Department:||Organismal Biology & Ecology|
|School Location:||United States -- Montana|
|Source:||DAI-B 68/11, Dissertation Abstracts International|
|Subjects:||Ecology, Entomology, Zoology|
|Keywords:||Allometry, Behavior, Coreidae, Evolutionary ecology, Heliconia bug, Leptoscelis tricolor, Maternal effects, Sexual selection|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be