As temperatures increase as the climate warms, these very hungry caterpillars may become even more hungry and plentiful. Harvest losses of pests can increase.
Insects will "eat more of our lunch," says Curtis Deutsch of the University of Washington in Seattle. Based on how heat stimulates the metabolism and reproduction of insects, he and his colleagues estimate that every degree Celsius of warming temperatures adds 10 to 25 percent additional damage to wheat, corn, and rice. Their prediction will appear on August 31 Science .
Insects already eat eight percent of the world's corn and wheat annually and damage 14 percent of the rice, says Deutsch. If the Earth's average global temperature is only 2 degrees above pre-industrial levels, corn's annual harvest losses could reach about 1
Unlike mammals and birds, insects heat or freeze like their environment. When an insect warms, the metabolism also accelerates. The faster it burns energy, the greedy it eats the insect and the sooner it multiplies. The acceleration rates are not very different in insect species, says German. So he and his colleagues developed a mathematical simulation of how many insects in the warmer time go on tour, multiply and devastate.
Where corn loses
As the earth warms, pest infestation of maize is increasing the most By the end of the century could show up in milder climates, predicts a new analysis. Places that are already near pest tolerance for high temperatures may lower insect reproduction and less damage see
Tropical insects are often already near the ceiling of their temperature tolerance, where an insect has to cope with as much heat damage as the reproductive effects in cooler temperate Zones where wheat is grown give insects much more latitude to live faster, making future wheat particularly vulnerable, says Deutsch.
This is "an incredibly valuable first step" in predicting future pest losses, says the physiological Ecologist Nathan Lemoine of Colorado State University in Boulder, who studies plant-insect interactions, but he and others note that insect metabolism is only one of many factors that will affect future crop yields for better or worse.
Farmers English The new costs are likely to be replaced by new protective measures According to Erich – Christian Oerke from the University of Bonn, who published data in 2006, which was the starting point for the new study, was not involved in the new calculations.
Rising temperatures can encourage or prevent insects from entering new areas. Temperatures can also affect the parasites that eat pests. Pests and plants can adapt and evolve. Predictions also need to evolve.
"I do not want people to think that this is a story that falls from the sky," says Deutsch. Hungry insects will not completely eradicate these crops. Nevertheless, any food loss can be a consequence for people who have become hungrier in a crowded world.