在红松鼠与竞争物种灰松鼠的生存斗争中，天敌松貂似乎成了红松鼠的一个意想不到的盟友。贝尔法斯特女王大学的科学家们发现，虽然松貂捕食红、灰松鼠两个物种，但灰松鼠更容易受到攻击。

Wide-eyed and cute as they appear, pine martens are sharp-clawed predators. Their agility and tree-climbing skills make them the enemy of any squirrel. But an innate fear of their predators seems, according to this research, to give the reds an edge over their grey competitors.

虽然从外表上看，它们眼睛睁得很大，又可爱，但松貂是长有利爪的捕食性动物。敏捷的行动力和高超的爬树技巧使它们成为所有松鼠的敌人。但根据这项研究，对掠食者与生俱来的恐惧似乎让红松鼠在其竞争对手灰松鼠的面前占有优势。

When the researchers applied pine martens' scent to squirrel-feeding stations, they found that only the red squirrels responded, showing much more vigilance when they sniffed out the danger.

在研究人员们给松鼠的喂食器上喷了松貂的气味后，他们发现只有红松鼠作出了反应，它们在嗅出危险时表现得更警觉。

Grey squirrels, on the other hand, seemed to ignore the scent and carry on regardless. This lack of a behavioural response, researchers say, means greys are much more vulnerable.

另一边，灰松鼠则似乎不顾松貂的气味，继续进食。研究人员说，这种缺乏行为反应的表现意味着灰松鼠更容易受到伤害。

But with more than two million grey squirrels in the UK and just 150,000 native reds, they could do with any advantage that evolution has given them.

但英国有200多万只灰松鼠，而仅有15万只土生土长的红松鼠，红松鼠需要利用进化赋予它们的任何有利条件。