|
Where Have All the Bees Gone? Colony collapse is a serious concern because bees play an important role in the production of about one-third of the foods we eat. As they feed, honeybees spread pollen from flower to flower. Without this process, a plant cant produce seeds or fruits. It could be that disease is causing the disappearance of the bees. To explore that possibility, Jay Evans, a researcher at the United States Department of Agriculture Bee Research Laboratory2, examines bees taken from colonies that are collapsing. We know what s healthy bee should look like on the inside, and we can look for physical signs of disease, he says. And bees from collapsing colonies dont look very healthy. Their stomachs are worn down, compared to the stomachs of healthy bees, Evans says. It may be that a parasite is damaging the bees digestive organs. Their immune systems may not be working as they should. Moreover, they have high levels of bacteria inside their bodies. If it turns out that a disease is contributing to colony collapse, bees genes could explain why some colonies have collapsed and others have not. In any group of bees there are many different kinds of genes. The more different genes a group has, the higher the groups genetic diversity. So far scientists havent determined the role of genetic diversity in colony collapse, but its a promising theory, says Evans. honeybee n. 蜜蜂parasite n. 寄生虫;寄生生物 pollen n. 花粉immune adj. 免疫的 expertise n. 专门知识，专长diversity n. 多样性 1. colony-collapse：群体瘫痪。Colony有殖民地的意思，在此意为： a group of the same kind of animals, plants, or one-celled organisms living or growing together. 一群生活或生长在一起的同种动物、植物或单细胞有机体。 3. the Florida Department of Agriculture：佛罗里达农业局。佛罗里达是美国东南部的一个州，濒临大西洋和墨西哥湾。 1. What is the mystery that researchers find hard to explain? B) 25-40 percent of the honeybees in the US have died. D) Honeybee hives are in disorder. A) Because honeybees produce one-third of the foods we eat C) Because honeybees eat seeds of flowers. 3. What are the possible causes of colony-collapse disorder given by the scientists? B) Disease and chemicals. D) Changes in genes structures. A) Bees genes allow them to expand their colonies. C) Bees genes make them fly from flower to flower. | 
