GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - U4WR70H7DT58XYJ9K

What causes size variation in bumblebee workers? In pollen storing species larvae develop in individual nest cells and are fed directly by adults. Thus, adults probably determine the size attained by each larva. Bumblebee larval cells are not as neatly organized as are those of honeybees, and larvae at the periphery of the brood may receive less care, then a ten-fold variation in worker mass results from the accidental neglect of some larvae. Given that larvae are reared in a controlled environment by specialized nest workers, it seems more likely that this size variation has an adaptive function and that the colonies benefit from rearing workers of a range of sizes.