The main area of my research focuses on the evolution of plant life history strategies, particularly those related to reproduction. In most flowering plants, all flowers and fruits are structurally and functionally identical. However, in some species, distinct flower and fruit types have evolved. Currently, my research investigates the dynamics of heterocarpy, a reproductive system in which different flowers on the same plant produce two or more types of fruits that have dramatically different dispersal and germination features. Some fruits are locally dispersed and have strong dormancy and other fruits are distantly dispersed and have no dormancy. I am continuing to study the fundamental ecology of this system in the gumweeds (Grindelia Asteraceae). Future studies will investigate the developmental processes underlying heterocarpy to better understand how this reproductive system evolves. Furthermore, an unexplored aspect of this reproductive system is how animals shape the reproductive behavior of heterocarpic plants, particularly through herbivory.
Another area of research interests is population genetics and mating system analysis, particular for endemic and rare species. Many endemic and rare species often have fragmented distributions, with individual populations being highly isolated from one another. This presents a challenge for these species due to restricted gene flow, high incidence of inbreeding, and other related phenomena. I am interested in the reproductive mechanisms these species use to overcome these problems and maintain genetic variation in their populations. I have studied this topic in temperate and tropical tree species. Currently, I am addressing these questions in the rare species seaside alder (Alnus maritima) which grows in south-central Oklahoma, the Delmarva Peninsula, and northwest Georgia. While this research does address questions of basic science, there is also and important conservation aspect to it as well.
In addition to my research, I am also interested in science education and outreach. My wife and I have recently co-authored two high school level reference books on plant ecology and diversity, and plan to pursue other projects in this area. Selected Publications
For more information about this program, contact the Department or Dr. Phil Gibson.