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DEVASTATING tropical storms can add to the richness of rainforests, say John
Vandermeer of the University of Michigan at Ann Arbor and his colleagues in the
US and Nicaragua. They looked at a rainforest in Nicaragua ravaged by Hurricane
Joan in October 1988. Over 10 years, they found that the number of tree species
doubled or tripled in eight storm-affected plots, compared with nearby ones in
an intact forest (Science, vol 290, p 788). By destroying the dominant
trees over a wide area, says Vandermeer, a hurricane gives other species a
chance to flourish.