Kin selection in plants: Theory and experiments with Impatiens capensi

Kin selection is a form of natural selection that allows adaptation at the group level. This dissertation describes both theoretical and empirical studies on the role of kin selection in plant populations. I present arguments and evidence that kin selection may be an important evolutionary process in many natural plant populations. When kin selection is occurring, plant-to-plant interactions will not be purely antagonistic in an evolutionary sense. This conclusion is contrary to current thinking in plant population biology.;The theoretical chapters of this dissertation are concerned with the various effects of population structure on kin selection. I present models that accommodate the hierarchical structure of most natural plant populations. The empirical chapters describe field studies of kin selection. These studies were performed on the North American annual plant, Impatiens capensis. I show that plant fitness depends strongly on interactions with neighboring plants and that the population structure of I. capensis is highly favorable to kin selection.