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In brief : Of mice and acorns

点击量:   时间:2018-02-20 01:02:05

ECOLOGISTS have discovered a chain reaction that leads from acorns to Lyme disease in humans, via mice and deer. Oak trees produce large crops of acorns every two to five years. Clive Jones of the Institute of Ecosystem Studies in Millbrook, New York, and his colleagues simulated this in a year when there were no large acorn crops by adding 3.5 tonnes of the acorns to small areas of forest. The acorn surplus boosted white-footed mouse populations by between three and sevenfold, and more deer entered these areas. Both animals are essential parts of the life cycle of the tick that carries Borrelia burgdorferi —the bacterium which causes Lyme disease in humans. The larval form of the tick was also eight times as abundant after the acorns were added, the team says (Science, vol 279, p 1023). Jones believes that by monitoring acorn numbers, it should be possible to predict which forests pose the highest risk of disease. “Then people can modify their behaviour accordingly,