科学美国人60秒 SSS 大敌当前小鱼也会为朋友两肋插刀（在线收听）

Guppy Groups Provide Friendly Protection against Foes 大敌当前小鱼也会为朋友两肋插刀

Humans aren't the only species that forms friendships. Lots of animals prefer to spend their time only with certain individuals.

人类并不是唯一一种会产成友谊的物种。有很多动物都喜欢只跟特定的某些伙伴在一起消磨时光。

"It's all very well showing that you do get social relationships and social bonds forming, but why on earth would you form them in the first place?"

“一切现象都明确显示，你的确会去建立社交关系和社会联系，但你建立它们的初衷究竟是什么？”

University of Exeter animal behavior researcher Rob Heathcote. He and his team wanted to find out what benefit animals derive from close social relationships. To do it, they set out for the Caribbean island of Trinidad, home of a small freshwater fish called the Trinidadian guppy.

埃克塞特大学动物行为研究员罗伯·希思科特说道。他和他的团队希望查明动物能从亲密的社会关系中得到何种益处。为此，他们出发前往加勒比的特立尼达岛——一种名为“特立尼达古比鱼”的小淡水鱼的故乡。

\"These guppies live in environments that have tons of predators around, so basically it really sucks to be a guppy. In some places they live, you'll be watching these shoals of guppies and a predator is attacking them every twenty or thirty seconds or so."

“这些古比鱼生活在周围有大量捕食者的环境中，所以做一个古比鱼真的挺糟糕的。在一些它们生存的地方，你会看到这些古比鱼鱼群，以及捕食者每隔20或30秒就会攻击它们。”

One common idea is that such animals form social groups to reduce the risk of being gobbled up. But Heathcote wanted to see whether the benefits of social living might come from the strength of individual social relationships rather than simple safety in numbers.

一种常见的观点是，这种动物通过形成社会团体来减少被吃掉的风险。但希思科特想了解，社群生活的好处是否有可能源自个人社会关系的紧密强度而不是简单的安全系数。

The researchers caught 240 female Trinidadian guppies and divided them into groups of fifteen, each group in its own small pool. While some of the fish were left alone, others were exposed to what looked like a predator—a doll version of a guppy-eating fish called a pike cichlid.

研究人员捕获了240条雌性特立尼达古比鱼，并将它们15条分成一组，每组都生活在自己的小水池里。一些鱼被单独放置，另一些鱼则被暴露在一个人造玩偶版、专吃古比鱼的棘鲷鱼面前。

Those guppies exposed to the ersatz predator were more likely to establish stronger social bonds. But the groups formed by those guppies were on average smaller than the groups formed by the fish that were not exposed to predators.

那些被暴露在“捕食者”面前的古比鱼更有可能建立更强的社会联系。但是，与那些未接触到捕食者的鱼所形成的鱼群相比，通常这些古比鱼所形成的群体相对较小。

Heathcote thinks that the tighter-knit friendships that come from small groups allow guppies to more effectively cooperate in their predator avoidance activities.

希思科特认为，来自较小群体的较紧密的联系，使得古比鱼能在躲避捕食者的活动中更有效地合作。

“You can either hang out with a load of guppies, and every time these predators attack, you're unlikely to be the one that gets eaten. But obviously the first thing that happens when you form a big shoal is that this attracts every single predator in the vicinity… The alternative is you can be inconspicuous in a small social groups of three [or] four individuals. Everyone's kind of looking out for each other, they've got each other's back."

“你可以和一群古比鱼出去玩耍，每当受到捕食者攻击时，你都不太可能成为被吃掉的那个。但很显然，形成一个大鱼群的首个影响就是会吸引附近的每个捕食者……另一种选择就是，你可以不显眼的呆在一个由三个(或)四个个体组成的小群体中。每个个体似乎都在互相照顾，大家都互相支持对方。”

So spending time with a few close friends could outweigh the benefits of blending in with the crowd, particularly in dangerous situations.

因此，与一些亲密的朋友共度时光可能要比与一大群同类厮混更有益处，尤其是在危险的情况下。

"Friendship," said Winnie the Pooh writer A. A. Milne through his character Christopher Robin, "is a very comforting thing to have."Especially when there's a big scary fish trying to eat you.

“友谊，”小熊维尼的作者艾伦·亚历山大·米恩通过他的角色克里斯托弗·罗宾说道，“是一件非常令人欣慰的事情。”特别是当有一条可怕的大鱼想要吃掉你的时候。