Traitorous Fish Throw Friends to The Wolves, Newscientist, July 11st, 2013
叛逆的鱼儿宁愿牺牲朋友来保全自己，新科学家科技杂志，2013年7月11日
If you're being chased by a hungry bear, you're more likely to escape if you have a friend running alongside you.
如果你被一只饥饿的熊追赶，在你有朋友在身边的情况下，你会更容易逃脱。
That way, the bear might kill your friend instead of you.
这样一来，这只熊可能会杀了你的朋友，而不是你。
In this situation, you're not really running away from the bear.
在这种情况下，你并没有真正逃离这只熊。
You're just trying to run faster than your friend.
你只是试图比你的朋友跑得更快。
It could be worse. You could try to trip your friend up or even break their leg, except you're probably too decent to do that.
这会让情况更糟。你可以试图绊倒你的朋友或打断他的腿，不过你可能太正直以至于不会那样做。
But a South American fish has no qualms.
但南美有一种鱼却并毫无顾忌。
At first glance, this small fish looks pretty innocuous, and many people in South America keep them as pets.
乍一看，这些身材娇小的鱼儿看起来并无伤害力，许多南美洲人都将其作为宠物来饲养。
However, they are a bit of a nuisance. "There's a big problem with fish entering hydroelectric power station machinery. "says Robert Young of the University of Salford in the UK.
然而，它们也会有一点点让人讨厌。英国索尔福德大学的罗伯特·杨说“当鱼进入水力发电站设备中时，就会带来很大的问题。”
So a few years ago, Young and his fellows started investigating ways to deter the fish from getting into the machinery.
所以几年前，杨和他的同事开始研究如何阻止鱼群进入设备。
To their surprise, they discovered that the astyanax bimaculatus turned on each other if a predator approached.
令他们吃惊的是，他们发现如果有捕食者接近时，这种大头丽脂鲤会自相残杀。
Small fish often protect themselves by swimming in large groups, making it hard for predators to target a specific fish.
小鱼通常会成群结队地在水中游泳来保护自己，这可以使捕食者很难瞄准某一个特定的鱼儿。
In theory, all animals that could become prey have an incentive to attack their fellows when the group is threatened.
但从理论上讲，当群体受到威胁时，所有可能成为牺牲者的动物都有袭击它们同伴的动机。
Young says other species might betray each other in the same way, but perhaps nobody has managed to ob-serve this behaviour yet.Thank you.
杨说，其他的物种也可能会以同样的方式背叛对方，但也许是因为尚未有人观察到这种行为。谢谢。
