Forest Speaks

Forest dynamics

How does a forest change over time? In the late 1970´s, researchers argued about the stability of tropical forests and about the origins of so many different species in the same place.

Is it possible to predict how species change as climate changes? Will the same species that are present now be here in 100 years? How important are random events (like a migratory bird dropping seeds of a species from another area into the forest)?



Botanists measured, mapped and identified more than a quarter of a million trees (all of the trees with a basal diameter greater than about a half an inch (1 centimeter)) in a 50 hectare area on Barro Colorado in 1980. They repeated this census in 1985, 1990 and 1995.

Now we know how fast more than 400,000 trees grow, where different species of trees prefer to live (on slopes or in flat areas, in sun or shade, in moist or dry areas), and whether individual tree species are becoming more common or more scarce on the island. The fact that all of the trees have been identified makes life much easier for researchers. They can easily find out what species of tree is dropping seeds or fruit, what kind of leaves a monkey is eating, what species of tree a fungus is growing on.


Astrid Ferrer studies fungi that rot wood; very important in a forest where so much biomass is generated. Even huge dead trees like this one decay very quickly.






Greg Gilbert and Zuleyka Maynard worked on a project sponsored by Sandoz pharmaceuticals to isolate fungi from plants and soil that might produce medicinal compounds.

Currently a large group of people including staff from STRI, the University of Utah, the University of Panama and Gorgas laboratories are beginning a similar project to look for medicinal compounds in plants.



Elizabeth Losos (Project director) and Richard Condit (STRI staff) direct a large project to establish sites like the 50 ha plot in other tropical forests in the world.






This world map shows the locations of some of the other forest dynamics research sites.