This is Scientific American’s 60-Second Science. I’m Christopher Intagliata.
这里是《科学美国人》的60 秒科学，我是克里斯托弗·英塔利亚塔。
It might seem obvious that the primary function of insect repellents like DEET is to, well, repel. But if you bring a pipette tip full of DEET right up to a mosquito, as Johns Hopkins neuroscientist Chris Potter did:
像避蚊胺(DEET)这样的驱虫剂，其主要功能好像就是驱赶，但如果你将装满DEET的移液器枪头直接怼到蚊子面前，就像约翰·霍普金斯医学院的神经科学家克里斯·波特(Chris Potter)所做的那样：
“She just ignores it. So that really does demonstrate that DEET by itself is not repellent, and it’s not going to make them fly away.”
“蚊子直接无视了枪头。所以，这的确证明了DEET本身没有驱蚊效果，它没法赶走蚊子。”
Potter’s team also genetically engineered Anopheles mosquitoes to make their antennae light up when their olfactory neurons picked up on a scent. But when they spritzed the antennae with DEET and other so-called repellents, even at 100 percent strength:
波特的团队还用上了基因编辑过的按蚊(Anopheles)，当嗅觉神经元感知到气味时，它们头上天线般的触须就会亮起来。但是，研究人员对着触须喷洒DEET以及其他驱蚊剂，甚至是强度达到百分之百的驱蚊剂：
“There just was no response. So that was a surprise to us. Going into this, we thought, ‘Okay, they’re insect repellents. They’re going to activate neurons; that’s how they repel mosquitoes.’ So then the question is, ‘What are they actually doing?’”
“就是毫无反应。所以，这点挺让我们惊讶的。考虑到这一点，我们以前认为：‘Ok，这些是驱虫剂，它应该会激活神经元，这就是它们驱赶蚊子的方式。’那么问题来了：‘驱虫剂到底是怎么驱虫的?’”
The researchers kept experimenting with those genetically modified mosquitoes to find out. A whiff of molecules commonly found on human skin made the mosquitoes’ antennae light up like a Christmas tree, Potter says. So they do sense us, which you’ve likely experienced. But when they combined compounds from our natural human perfume with DEET and other synthetic repellents, the antennae just flickered dimly.
研究人员继续用那些基因编辑过的蚊子来做实验，希望找出其中的机制。波特说，人类皮肤表面的一些常见分子的气味能让基因编辑蚊子的触须发光，就像圣诞树上的灯饰被点亮了一样。所以，蚊子确实能够“闻到”我们，你很可能已经亲身经历过了。但当研究人员将人类的天然体味和DEET以及其他人工合成的驱蚊剂混合在一起后，蚊子的触须只是微弱地闪烁了几下。
“So these odors, which, before, would strongly activate the olfactory system, essentially now didn’t do anything.”
“所以这些气味在之前能够强烈地激活(蚊子的)嗅觉系统，而现在什么都做不了。”
Meaning repellents like DEET actually act like an invisibility cloak against mosquitoes. The details are in the journal Current Biology. [Ali Afify et al., Commonly used insect repellents hide human odors from Anophelesmosquitoes]
这表明在蚊子看来，像DEET这样的驱蚊剂就像一件隐身斗篷。具体细节发表在《当代生物学》(Current Biology)杂志上。
Natural repellents, on the other hand, like lemongrass oil, stronglyactivated the skeeter’s senses in a negative way. And they weren’t as affected by masking chemicals like DEET. So the scientists say maybe you could combine them—to both offend the mosquitoes’ senses and to mask the more irresistible scent—of you.
然而，像柠檬草油这样的天然驱蚊剂，则是散发让蚊子强烈反感的气味，而且它们不会受到掩盖性化学物质(比如DEET)的影响。所以科学家建议，也许可以两者结合使用，一边让蚊子“倒胃口”，一边掩盖住你那极为诱蚊的“体香”。
Thanks for listening for Scientific American 60-Second Science, I'm Christopher Intagliata.
感谢收听《科学美国人》的60 秒科学，克里斯托弗·英塔利亚塔报道。
This is Scientific American’s 60-Second Science. I’m Christopher Intagliata.
It might seem obvious that the primary function of insect repellents like DEET is to, well, repel. But if you bring a pipette tip full of DEET right up to a mosquito, as Johns Hopkins neuroscientist Chris Potter did:
“She just ignores it. So that really does demonstrate that DEET by itself is not repellent, and it’s not going to make them fly away.”
Potter’s team also genetically engineered Anopheles mosquitoes to make their antennae light up when their olfactory neurons picked up on a scent. But when they spritzed the antennae with DEET and other so-called repellents, even at 100 percent strength:
“There just was no response. So that was a surprise to us. Going into this, we thought, ‘Okay, they’re insect repellents. They’re going to activate neurons; that’s how they repel mosquitoes.’ So then the question is, ‘What are they actually doing?’”
The researchers kept experimenting with those genetically modified mosquitoes to find out. A whiff of molecules commonly found on human skin made the mosquitoes’ antennae light up like a Christmas tree, Potter says. So they do sense us, which you’ve likely experienced. But when they combined compounds from our natural human perfume with DEET and other synthetic repellents, the antennae just flickered dimly.
“So these odors, which, before, would strongly activate the olfactory system, essentially now didn’t do anything.”
Meaning repellents like DEET actually act like an invisibility cloak against mosquitoes. The details are in the journal Current Biology. [Ali Afify et al., Commonly used insect repellents hide human odors from Anophelesmosquitoes]
Natural repellents, on the other hand, like lemongrass oil, stronglyactivated the skeeter’s senses in a negative way. And they weren’t as affected by masking chemicals like DEET. So the scientists say maybe you could combine them—to both offend the mosquitoes’ senses and to mask the more irresistible scent—of you.
Thanks for listening for Scientific American 60-Second Science, I'm Christopher Intagliata.
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