7 July 1998

Rethinking Forest Conservation

Tropical forests are disappearing at an alarming rate, but what's left behind might be just as big a biological problem. Recent research by scientists at the University of Georgia has shown that trees left behind during clearing can dominate subsequent reproduction, creating a genetic "log jam". Without genetic diversity both plants and animals face an uncertain future.

New techniques allow individual mapping of the genetic parent trees within forests.

This is a major breakthrough for botanists and is an extension of techniques used in identifying human parents and their children. The team from the University of Georgia studied Symphonia globulifera, a relatively unknown premontane rain forest in Costa Rica.

Their findings indicate that maintaining genetic diversity in forests is very difficult because regrowth species tend to dominate, creating a very shallow genetic pool and inbreeding in subsequent generations. Which means apparent healthy regrowth in logged forests may not be genetically "healthy" after all.