The surprising reasons animals play dead - Tierney Thys

Imagine you're being attacked by a ferocious predator.

想像你正被某个凶猛的掠食者攻击

With no chance of escape, you do what any courageous, self-respecting possum would do: curl into an immobile state called catatonia, stick out your tongue, drool, and ooze some foul-smelling liquid from your anal glands.

毫无脱逃的机会，你做了任何一只勇敢、有自尊的负鼠都会做的事 :把自己卷成一团僵硬不动，称作紧张症的状态，吐出舌头、无法控制地流口水、并从肛门腺排出恶臭的液体。

Disgusted, your assailant loosens its grip, decides you're not the dinner it was looking for, and departs.

攻击者因为觉得恶心而放松了钳制，心想你并非他的晚餐人选便离开了。

After 10 minutes, you resurrect and merrily saunter on.

10 分钟过后，你原地复活并兴高采烈地继续游荡

From lemurs to lizards, ants to amphibians, sharks to chickens, hundreds of animals "play dead" as a survival tactic.

从狐猴到蜥蜴、蚂蚁到两栖类动物、鲨鱼到鸡只，数以百计的动物们把「装死」视为一种求生战术

Nicknamed "playing possum" after its star performer, feigning death is also called thanatosis.

以其备受瞩目的「假扮负鼠」谑称之佯装死亡也被称作假死状态

That's from Thanatos, the ancient Greek deity of death.

这个字源于 Thanatos，古代希腊神祉中的死亡之神

But most scientists call it tonic immobility, or TI.

但大部分的科学家称它为紧张性麻痹，或是缩写为 TI

How and why TI occurs depends on the species and situation.

TI 发生的状态和原因取决于物种和当时的状况

Spewing stench and adopting odd postures are common and often play important roles.

吐出恶臭跟采取奇特的姿势都是常见的手段，也经常扮演重要的作用

Other animals sacrifice their neighbors: quail chicks that freeze while their kin run amok have a better chance of survival when pursued by a cat.

其他物种则把他们的邻居当作牺牲品 在同类四处窜逃时静止不动的鹌鹑幼雏，在被猫追捕的状况下生存率较高。

Speaking of cats, feline mothers can pinch the napes of their kittens' necks and induce another kind of immobility called clipnosis.

说到猫，身为母亲的猫科动物会叼住幼崽的后颈上方，借以制造称作 clipnosis 的另一种型态的静止不动

This keeps their kittens quiet and easy to transport.

这能让它们的幼崽保持安静并易于移动

Most of the physiological mechanisms underlying these theatrics originate in the parasympathetic nervous system, better known for controlling cycle of resting and digesting.

这些戏剧性效果背后大部分的生理机制源于副交感神经系统，以控制休息和消化的周期而闻名。

In possums, the parasympathetic nervous system causes their heart rates to drop by nearly half, respiration by a third, and body temperatures by more than half a degree Celsius for up to an hour.

对负鼠来说，副交感神经系统使他们的心跳率下降将近一半、呼吸量减少三分之一、身温降低超过 0.5 度长达一个小时

The neurotransmitter dopamine also plays a part.

神经传递物质多巴胺也发挥了作用

Flour beetles with low dopamine levels play dead more frequently than those with high levels,

体内多巴胺含量低的扁拟谷盗甲虫会比那些含量高的甲虫更频繁地装死，任何阻断多巴胺受点的物质都可以延长紧张症的时间。

But maintaining a death ruse isn't easy.

但要维持装死的诡计并不容易

The performers are constantly gauging their surroundings for cues on when it's safe to rise.

装死者不断地衡量他们周围的环境，寻找何时可以安全起身的提示。

Chickens, for instance, can sense when a predator's eyes are upon them.

以鸡只为例，它们可以感知掠食者的视线何时落在它们身上

Researchers know this because when they used a stuffed hawk in an experiment, their chicken subjects came out of their catatonia quicker when the hawk's eyes were averted.

研究人员之所以得知这点，是因为当他们在实验中使用老鹰绒毛娃娃时，他们的研究目标鸡只在老鹰的目光被移开时，

会更早从紧张症状态中复苏

Other animals use TI for purposes other than defense.

其他动物实行 TI 是为了防御以外的目的

When the sleeper cichlid feels peckish, it sinks to the lake floor and lies motionless, its splotchy coloration making it seem like a rotting carcass.

当雨丽鱼属的生物感到饥饿时，它沉到湖底，动也不动它身上的斑点分布使其看来像具腐烂的尸体。

If a small scavenger investigates, this undead trickster strikes.

如果有一只食腐小鱼前往查看，这个装死的谋略家就出击猎食

Some animals even feign death as a sexual ploy.

有些动物甚至把装死亡当作是一种性花招

Male nursery spiders offer gifts of silk-wrapped insects in hopes of wooing females.

苗圃公蜘蛛把用丝绸包裹的昆虫作为礼物,以求吸引雌性.

But those females are known to eat love-seeking males.

但那些雌性以捕食求爱的雄性闻名

By playing dead while the female eagerly devours her snack, these males can cautiously revive and improve their chances of successfully mating.

当雌蜘蛛症饥渴的大快朵颐她的点心时，借着装死，这些雄蛛可以小心翼翼地复原并提升他们的成功交配的机率.

So TI can work to an animal's advantage, unless someone else knows its secret.

因此 TI 对动物而言可说是一种优势，除非有人知道这个秘密

California orcas can flip over young great white sharks, inducing TI for so long the immobilized sharks, who must move to respire, essentially suffocate.

加州逆戟鲸会掀翻年轻的大白鲨，让因 TI 而长时间静止不动的鲨鱼，必须呼吸，基本上窒息而死.

Humans can also flip sharks into TI.

人类也可以让鲨鱼进入 TI 状态

By stroking a shark's electrically-sensitive snout and gently turning it over, researchers can induce TI that lasts up to 15 minutes.

透过电击鲨鱼对电敏感的口鼻部，并温柔地将鲨鱼翻身，研究人员可以造成最高持续 15 分钟的 TI 状态.

That’s enough time to insert tags, remove hooks, and even perform surgeries.

这对植入标签、移除钩子、甚至是进行手术来说都是相当足够的时间了.

There are risks however: TI can hamper respiration and induce hyperglycemia, a sign of stress.

然而这之中仍存有风险 :TI 会妨碍呼吸并诱发高血糖，压力的一种征兆

So this technique should only be used when necessary.

所以这种技巧只应在必要时使用

Humans can also experience TI when they freeze with fear during violent assaults.

人类在因暴力的攻击而害怕到无法动弹时也可能经历 TI

Recognizing this ancient, involuntary form of self-defense has significant implications when trying to understand why some victims don't flee or fight in the face of danger.

对这种古老的，非自愿的自卫形式有所认知有着重大意义。特别在试图理解为何有些受害者在面对危险时不逃或抵抗时

So, studying TI in non-human animals not only helps us better understand some odd behaviors, it can also help us better understand our own, sometimes counterintuitive, responses to violence.

所以，在人类以外的动物身上研究 TI不只协助我们更了解某些怪异的行为，也能协助我们更了解我们自己，有时会违反直觉对暴力做出反应.