Neutral theory rests on the assumption that all species are equal in terms of their ability to survive and reproduce. Chance events drive change. This study supports an alternative, older explanation that characteristics of individual species play an important role in determining the structure of the community, contributing to the maintenance of biodiversity through distinct strategies.
"If the neutral theory is correct, we would expect these traits to be distributed at random throughout the forest, but that was not the case," explained RenatoValencia, professor at Pontificia Universidad Catlica del Ecuador and lead investigator at the Yasuni forest plot.
Nathan Kraft, PhD candidate at the University of California, Berkeley, measured and compiled traits of the leaves, seed and wood of trees at Yasuni and then used detailed maps from the plot to look at how these traits are distributed across the forest.
"The traits we measured give us important clues about the strategy of each species in the forest how they make a living, if you will. One exciting thing that we found is that trees growing near each other in basically the same habitat, may employ very different strategies," Kraft explained.
More research will be needed to resolve these conflicting views, and participants in the CTFS/SIGEO network of more than 30 forest dynamics plots in 17 countries hope that researchers will take advantage of standardized life-table data from more than 6,500 tree species to understand the patterns of biological diversity across the world.
|Contact: Beth King|
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Smithsonian Tropical Research Institute