科学美国人60秒 SSS 工作努力的蛇 蛇液毒性更强（在线收听）

Harder-Working Snakes Pack Stronger Venom

Movies like Raiders of the Lost Ark, Snakes on a Plane and even Harry Potter and the Chamber of Secrets have all relied on the fear of snakes to build suspense and anxiety. About a third of all people are at least a bit phobic about snakes.

像《夺宝奇兵》、《飞机上的蛇》甚至《哈利波特与密室》这样的电影都是靠对蛇的恐惧来制造悬念和焦虑。大约三分之一的人对蛇至少有点恐惧。

Some of the distress when it comes to the slithering serpents comes from their unpredictable movement patterns. But the fear also stems from knowing that, well, snake bites do kill a lot of people—perhaps as many as 94,000 people annually.

当涉及到滑行蛇时，一些痛苦来自于它们不可预知的运动模式。但是恐惧也源于知道，嗯，蛇咬伤确实会杀死很多人——也许每年多达94000人。

But not all snake venom is created equal. Some snakes have venom only strong enough to kill a couple of mice. On the other hand, there’s “the inland taipan in Australia, which is incredibly venomous. It has enough potent venom to kill about 50 adults. Humans.”

但并不是所有的蛇毒都是一样的。有些蛇的毒液只够杀死几只老鼠。另一方面，还有“澳大利亚内陆的太攀，毒性非常大。”它的毒液足足可以杀死大约50个成年人。人类。”

Kevin Healy, a lecturer in zoology at the National University of Ireland, Galway.

凯文·希利是戈尔韦爱尔兰国立大学动物学讲师。

He wanted to know why snake venom toxicity varied so much, so he and his team looked at 102 different venomous snakes species. They examined how much venom the snakes had as well as what they ate and what kind of habitat they lived in. The key finding:

他想知道为什么蛇毒的毒性差异如此之大，所以他和团队观察了102种不同的毒蛇。他们研究了这些蛇有多少毒液，吃什么，住在什么样的栖息地。发现的关键在于:

“Bigger snakes have more venom, in general. But the amount of the increase of that venom increases basically according to how much energy you burn per second, not how big your prey is, as you'd expect.”

“一般来说，较大的蛇有更多的毒液。但是毒液的增加量基本上是根据每秒消耗的能量而增加的，而不是你所期望的猎物有多大。”

The study was in the journal Ecology Letters.

这项研究发表在《生态学快报》杂志上。

The researchers also found snakes that inhabited three-dimensional environments that include things like trees and water had less venom than snakes that live two-dimensionally—that is, on the ground.

研究人员还发现，生活在包括树木和水在内的三维环境中的蛇比生活在二维环境(即地面)中的蛇的毒液要少。

“Our guess is that that comes back to encounter rate. So if you live in a 3D environment, just the pure physics of living in a 3D environment means you will bump into more things. And so what that means is you might not need this really large reservoir of venom to kind of ensure that if you miss a prey item, that you have something for the next time because you're not going to get to encounter individuals that often.”

我们的猜测是，这回到了遇难率。所以如果你生活在3D环境中，3D环境中的纯粹物理就意味着你会遇到更多的东西。所以这意味着可能不需要这么大的毒液库来确保以免错过了猎物，下次就没有东西吃了，因为你会经常遇到猎物。”

Whereas the 2D-dwelling snakes need to make sure that when they get a chance for a meal, their venom will pack a punch. Of course, only about a quarter of all snake species have venom at all. Keeping that in mind may make it possible to be braver than Indiana Jones—when it comes to snakes, at least. You should still be very scared to crawl under a moving truck.

而生活在2d世界的蛇则需要确保当它们有机会进食时，它们的毒液会产生强大的冲击力。当然，只有大约四分之一的蛇类有毒液。记住这一点可能会让你比印第安纳·琼斯更勇敢——至少在蛇的问题上。你应该仍非常害怕从移动的卡车下爬过去。