同類相食有助於毛毛蟲對抗傳染病

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.

本·範·阿倫喜歡收集毛毛蟲。在路易斯安那州立大學做博士後研究時，範·阿倫看到一些毛毛蟲會把同類當午餐吃掉。

Rather than cry over his losses, Van Allen took advantage of the cannibalism for his research.

他並沒有因毛蟲的減少而傷心，而是利用這種同類相食的現象來進行科學研究。

"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."

“一般來說，吃同類是很有營養的，因爲它們含有你體內的所有營養元素，因而可以說它們是利於消化吸收的食物。”

"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."

“這種行爲也會爲你減少競爭對手--畢竟吃掉一個同類就意味着少了一個在同一地區和你爭搶同一種食物的對手。而且由於大家都生活在同一個地方，所以通常也很容易看到同類。”

Van Allen and colleagues collected the caterpillars to study disease transmission in lepidoptera -- moths and butterflies.

範·阿倫和他的同事們收集了這種毛毛蟲，來研究鱗翅類物種（蛾類和蝴蝶）的疾病傳播。

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.

在對這種會同類相食的物種進行了觀察之後，他們對這種嗜食同類的喜好是否會對個體有危害感到很好奇--假設一個個體吃掉了一個患有傳染病的同類，但這對種羣來說則是有益的--因爲它將傳染者從羣體中消滅了。

"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."

“我們的主要觀點是，儘管這對個體來說是件冒險的事，但由於這類生物更加傾向於同類相食，這實際上從一開始就預防了傳染病進入該種羣。”

Van Allen's study is in the journal American Naturalist.

範·阿倫的這項研究發表在了《美國自然主義者》雜誌上。