Warmer Climate May Boost Bad Bugs

Roughly one third of this legume leaf was consumed by an unknown insect more than 55 million years ago.

Bugs Like Warmth

“Our study suggests that increased insect feeding on plants is likely to be a net, long-term effect of anthropogenic carbon dioxide increase and warming temperature,” the researchers reported in February in the Proceedings of the National Academy of Sciences.

By looking at modern insect’s behavior, the researchers can determine the types of insects eating the fossil leaves. They compare modern leaf damage to that occurring in the past.

The team found that the percent of leaves damaged by insects was 15 to 38 percent during the Paleocene and 33 percent during the Eocene, but increased to 57 percent during the warmer PETM. This large increase in insect herbivory corresponded to a time of increased carbon dioxide and temperatures. The researchers also found that the increased feeding occurred in all plant species and that a more diverse array of insects fed on the leaves.

Source: Penn State University