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Bee death

In this photo provided by San Francisco State University, an Apocephalus borealis fly implants its eggs into the abdomen of a honey bee. The A. borealis fly is suspected of contributing to the decrease in the honey bee population. Researchers say the fly deposits its eggs in the abdomen of honey bees and as the larvae grow within the body of the bee, the bee begins to lose control of its ability to think and walk, flying blindly toward light. It eventually dies and the fly larvae emerge. (AP Photo/Christopher Quock, San Francisco State University)

Bee death mystery continues

A common class of pesticide is causing problems for honeybees and bumblebees, important species already in trouble, two studies suggest. But the findings don't explain all the reasons behind a long-running bee decline, and other experts found one of the studies less than convincing.