As global warming affects the Earth's climate, a Tulane University scientist is predicting a significant increase in caterpillars and agricultural damage.
"That's really of great concern, especially to agricultural systems where we rely on several of these parasites. They keep outbreaks from occurring," said Lee Dyer, a biologist at Tulane University in New Orleans.
How that climate variability will affect ecosystems has proven difficult to test, National Geographic News reported Wednesday.
In search of an answer, Lee Dyer, a biologist at Tulane, and his colleagues examined data on parasitism in caterpillars from 15 caterpillar-rearing programs in different climate regions.
The biologists found parasitism, the greatest control for insect pests such as caterpillars, decreases as climate variability increases.
"Parasitoids are the most important source of biological mortality for most caterpillars," Dyer said. "Most people think of birds eating caterpillars, but they are nothing compared to the amount of death inflicted by wasps and flies."
Dyer and his colleagues report their finding in an upcoming edition of the Proceedings of the National Academy of Sciences. An online early edition of the study was posted Monday on the journal's Web site.
Copyright 2005 by United Press International
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