注释：
1. industries：行业
2. for decades：有几十年。for后接复数的时间词是常用结构,如for days,for years等。本文第四段还会出现for years。
3. “That’s the great thing about ants.”：great thing指前一句的ants are so common throughout the region。
4. tree harvesting：伐林
练习：
A This allowed scientists to gauge the pace and progress of the ecological recovery.
B Yet in other businesses, such as farming and property development, ant surveys aren’t used widely.
C Employing those people are expensive.
D They do this by sorting the ants, counting their numbers and comparing the results with those of earlier surveys.
E The evolution of ant species may have a strong impact on our ecosystem.
F Others will die out for lack of food.
答案：1.F 2.D 3.A 4.B 5.C
