This is Scientific American — 60-Second Science. I'm Emily Schwing.
Ben Van Allen collects caterpillars. While doing postdoctoral research at Louisiana State University, Van Allen saw that some of the caterpillars were having others for lunch. Rather than cry over his losses, Van Allen took advantage of the cannibalism for his research.
"Generally speaking, it's nutritious to eat the same species, because they have all the nutrients that are already inside you, so it's an easy-to-process meal."
"It also reduces the amount of competition you are going to experience – it's just one fewer individual trying to eat the same food you are, in the same area. And it's usually easy to find members of the same species too, since they live in the same place you do."
Van Allen and colleagues collected the caterpillars to study disease transmission in lepidoptera—moths and butterflies. After observing the cannibalism they wondered if their subjects' appetite for each other might be dangerous for the individual—if it ate an infected cousin—but benefit the group—by removing the infected individual from the population.
"Our main point is that, while that is an individually risky thing for a cannibal, as populations are more cannibalistic, they actually prevent diseases from getting into the population in the first place."
Van Allen's study is in the journal American Naturalist.
It was released at the same time as a study in the journal Nature Ecology & Evolution that showed that chemicals produced by plants can ward off caterpillars, by inducing the caterpillars to eat each other instead of the plants.
"It would be kind of an ironic thing, if a disease was coming into this caterpillar population and the plants caused them to become more cannibalistic and that prevented the disease from coming in and actually ended up worse for the plant than it was in the first place."
Worse for the plant because the cannibal behavior caused the caterpillar population to wind up healthier—and hungrier.
Thanks for listening for Scientific American — 60-Second Science Science. I'm Emily Schwing.
本·范·艾伦喜欢收集毛虫 。在路易斯安那州立大学做博士后研究时，范·艾伦亲眼看到一些毛虫把同类当午餐吃掉 。范·艾伦并没有因损失毛虫而哭泣，而是利用这种同类相食现象来进行研究 。
“同类相食还能为毛虫减少未来竞争对手的数量，吃掉一只同类，就等于少了一个在同一地区和你争夺同一种食物的个体 。而且由于都生活在同一个地方，所以通常很容易找到同类 。”
范·艾伦和同事收集毛虫，以研究飞蛾和蝴蝶等鳞翅目昆虫间的疾病传播 。在观察同类相食现象之后，他们想知道毛虫进食同类的欲望对个体来说是否存在危险，比如毛虫可能会吃掉感染疾病的表亲，当然这对群体来说是有益的，因为群体中的染病个体被清除掉了 。
谢谢大家收听科学美国人——60秒科学 。我是埃米莉·施温 。
1. take advantage of 利用；
例句：You may wish to take advantage of our instructional session.
2. in the first place 起初；一开始；
例句： don't think we should have been there in the first place.
3. ward off 避开，躲开，防止(危险、疾病等)；
例句：She may have put up a fight to try to ward off her assailant.
4. wind up 最终沦落到；最终落得；(以…)告终；
例句：Both partners of the marriage wound up unhappy.