(单词翻译:单击)
听力文本
This is Scientific American — 60-Second Science. I'm Karen Hopkin.
A good disguise keeps you hidden, right? Well, sometimes the best disguise is actually the most dazzling. Because research reveals that flashy metallic iridescence can visually baffle predators. Which allows colorful prey to survive another day. Those eye-popping results appear in the journal Scientific Reports.
Shimmering iridescent coloration...which changes depending on the angle from which it's viewed...is favored by everything from birds to beetles and blossoms to butterflies.
"And in our research group we are of course interested in why this vivid metallic coloration is so taxonomically widespread in nature."
Karin Kjernsmo of the University of Bristol. She says that in some cases the showy splashes of light are a sexual strategy.
"Here I would like to point out that in some species, particularly those that display strong sexual dimorphism, such as birds of paradise or the pea fowl or even in some butterflies or fishes, the occurrence of iridescence is most likely driven by sexual selection. For example, in many of these cases it is the males that have these vivid iridescent colors and they use them in mate choice or they use them as a signal to attract mates."
But iridescence also shows up in situations where reproduction is not an issue...for example, in caterpillars or chrysalises.
"So what we are studying now is whether natural selection imposed by predation could explain the occurrence of iridescence in prey animals."
The idea that eye-catching colors could be used as a cover-up isn't a new one.
"The father of camouflage theory, Abbott Thayer, he really believed that iridescence should be categorized as a camouflage strategy. And he wrote in his famous lifework Concealing-Coloration in the Animal Kingdom, already in 1909, that 'brilliantly changeable or metallic colors are among the strongest factors in an animal's concealment.' And this sounds like a completely counterintuitive thing to say, because how can colors that are both brilliant and changeable contribute to animal's concealment?"
After all, when we think of camouflage, we tend to think about blending in to the background. But there are forms of camouflage...called disruptive coloration...that work by breaking up an animal's otherwise tell-tale shape.
"In a similar way, we were asking whether iridescence, due to its changeability, could work as a form of camouflage by obstructing shape recognition."
Kjernsmo and her colleagues trained bumblebees to associate a particular shape... a circle or an oval...with a sugar reward. And they found that the bees, when given a choice, would preferentially visit the shape they knew to be sweet. But when the shapes were iridescent, the bees had trouble telling them apart.
"It seemed that the strikingly iridescent surfaces on our targets visually broke up the otherwise recognizable shape of the targets."
Which made them hard to distinguish.
As for making use of this method for hiding in plain sight...
"Any practical applications is of course directly linked to any industry that has an interest in camouflage, that is how to conceal objects or make them more difficult to recognize."
The researchers are currently conducting experiments with birds...which often prey on iridescent insects. To see if it helps to have a bird's-eye view.
Thanks for listening for Scientific American — 60-Second Science. I'm Karen Hopkin.
参考译文
这里是科学美国人——60秒科学。我是凯伦·霍普金。
好的伪装能让你隐藏，对吧？有时最好的伪装其实是最耀眼的。因为研究发现，闪闪发光的金属彩虹色可以在视觉上迷惑掠食者。这使色彩鲜艳的猎物可以多活一天。这项令人瞠目结舌的研究结果发表在《科学报告》期刊上。
根据观看角度不同而发生变化的闪耀彩虹色备受各种生物的青睐，无论是鸟类、甲虫，还是花朵和蝴蝶。
“在我们的研究小组中，我们当然对为什么这种生动的金属色在自然界中如此广泛地存在感兴趣。”
布里斯托尔大学的卡琳·杰恩斯莫说到。她说，在某些情况下，耀眼的灯光是一种性策略。
“在这里我想指出的是，在某些物种中，尤其是那些表现出强烈两性差异的物种，比如天堂鸟、孔雀，甚至在某些蝴蝶或鱼类中，彩虹色的出现很可能是由性别选择所驱动的。举例来说，在这些研究案例中，有很多是雄性的外表呈现鲜艳的彩虹色，它们以此来选择配偶或是作为吸引配偶的信号。”
但彩虹色也会出现在不涉及繁殖的情况下，比如，在毛毛虫或蛹中。
“因此，我们现在正在研究的是，捕食所施加的自然选择是否能解释猎物身上出现彩虹色的原因。”
引人注目的颜色可以用来伪装，这种想法并不新鲜。
“伪装理论之父阿伯特·塞耶坚信，彩虹色应该被归为伪装策略。他在他的著作《动物王国》中写道，早在1909年，‘动物隐藏行为的最重要因素之一就是耀眼地变化或金属色。’这听起来像完全违反常理的事，因为耀眼又多变的颜色怎么可能有助于动物的隐藏呢？”
毕竟，在想到伪装时，我们倾向于认为应该融入背景之中。但是有种伪装形式名为破坏性伪装，其通过破坏动物的其他特征来发挥作用。
“同样地，我们想知道，基于易变性，彩虹色是否能将阻碍形状识别作为伪装的一种形式。”
杰恩斯莫和同事训练大黄蜂，把圆或椭圆等特定形状和糖奖励联系起来。他们发现，在可以选择时，大黄蜂会优先选择它们知道是甜的形状。但是当形状呈彩虹色时，大黄蜂很难进行区分。
“我们的目标那视觉上引人注目的彩虹色表面似乎破坏了原本可辨认的形状。”
这使它们难以区分。
至于利用这种方法隐藏在显眼的地方……
“当然，任何实际应用都与任何对伪装感兴趣的行业有直接联系，即如何隐藏物体或使它们更难识别。”
研究人员目前正在对鸟类进行实验，这些鸟类的饮食中经常含有彩虹色的昆虫。实验目的是看看鸟类的视角是否能提供帮助。
谢谢大家收听科学美国人——60秒科学。我是凯伦·霍普金。
译文为可可英语翻译，未经授权请勿转载！
重点讲解
重点讲解：
1. show up (使)清晰；(使)变得明显；(使)显现出来；
The orange tip shows up well against most backgrounds.
橙色的尖端在大多数背景下都很醒目。
2. break up （使）分裂；（被）拆分；(使）破碎；
The accidents of emergency pollution will threaten the health and could break up the organisms 'environment.
突发性环境污染事故威胁着人类健康，是破坏生态环境的重要因素之一。
3. tell apart 区分；区别；辨别；
Medication overuse headache is difficult to tell apart from the original headache so it can be very difficult to diagnose.
药物滥用所引起的头痛常常难以同原本的病痛区别开，因此也难以诊断。
4. make use of 利用；
We could make better use of our resources.
我们可以更有效地利用我们的资源。
