Stirring the Gene Pool: Will Data on Trees Lead to Forest of Understanding?

Understanding the genetic structure of ecosystems is important in saving biodiversity. That's especially vital as humans fragment vast natural areas into isolated patches, cutting off avenues for outcrossing. Unfortunately, scientists' understanding of breeding systems and gene flow may be even more fragmented than the ecosystems. Botanists are hard at work remedying the situation. Using genetic markers, they analyze plant paternity and infer how far pollen travels on gentle breezes or the bac

Rry Palevitz
Sep 26, 1999

Understanding the genetic structure of ecosystems is important in saving biodiversity. That's especially vital as humans fragment vast natural areas into isolated patches, cutting off avenues for outcrossing. Unfortunately, scientists' understanding of breeding systems and gene flow may be even more fragmented than the ecosystems.

Botanists are hard at work remedying the situation. Using genetic markers, they analyze plant paternity and infer how far pollen travels on gentle breezes or the backs and bills of animal pollinators. By comparison, however, not much is known about maternal gene flow in seeds after fertilization. "Seed movement is tougher to analyze, so it's been less well studied," says James Hamrick, population biologist at the University of Georgia.

Matthew Hamilton, assistant professor of biology at Georgetown University, has now partially filled the seed void using the tropical tree Corythophora alta. As major primary producers in terrestrial ecosystems, trees provide food and...