介绍： 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 ignore...

介绍： 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. Just 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.

这里是科学美国人——60秒科学系列，我是克里斯托弗·因塔格里塔。
显而易见，避蚊胺等驱蚊剂的主要功能是驱蚊。但如果你像约翰霍普金斯大学的神经学家克里斯·波特那样，将装满避蚊胺的吸管直接放到蚊子面前：
“蚊子会无视它。因此，这确实证明避蚊胺本身并不是驱蚊剂，不会将蚊子赶走。”
波特的团队还对按蚊进行了基因改造，使其嗅觉神经元嗅到气味时触须会发光。但当他们用避蚊胺和其他所谓的合成“驱蚊剂”喷洒触须时，即便浓度为100%：
“蚊子也没有任何反应。这令我们相当吃惊。一开始我们认为：这些是驱蚊剂。它们会通过激活神经元的方式来驱蚊。然后问题就变成，‘它们到底是如何做到的？’”
为了找到答案，研究人员一直用这些经过基因改造的蚊子进行实验。