火蚁奇特的物理性质之每日学一遍英语

这团黏糊糊的棕色物质很像泥巴 但它其实是有生命的
它是由火蚁组成的
红火蚁
拉丁语是不可打败的意思
确实 这些火蚁刚从它们群落的重大灾难中幸存下来
它们被铲到了一个桶里
在桶中缓缓灌满了水
但它们存活下来了
它们得以幸存的原因也是
它们被带到这里的原因
这里不是动物实验室
也不是生态学研究现场
这里是乔治亚理工的工程学院
Joss: I guess my first question is…
我想我第一个问题是
What makes fire ants interesting to a bunch of engineers?
是什么让工程师觉得火蚁有趣呢？
David Hu: Fire ants are one of the few insects capable of building
火蚁是极少数能用自己的身体
big structures with their bodies.
组成巨大结构的昆虫之一
And they can do it by linking their bodies together.
它们通过彼此身体相连来实现这种能力
That means fire ants aren’t just animals—
这说明火蚁不仅是动物
they can also be seen as a sort of material
还可以被视为是一种可测试的材料
that you can test like a fabric or a gel.
就像纤维和凝胶那样
And you can trace that behavior back to their evolutionary history.
这种行为可以追溯到它们进化史中
Red imported fire ants are native to floodplains in South America
红火蚁起源于南美洲的洪泛区
where the rainy season regularly inundates their underground homes.
雨季时它们的地下居所常被淹没
The ants that stick together and stay with the queen have a better chance of reproducing,
紧密相连在蚁后身边的火蚁有更高的繁殖机会
so they’ve gotten really good at basically holding hands
所以火蚁非常擅长手牵手
and floating until they find a new place to live.
漂浮着直到找到新的栖息地
In the 1930s or 40s, shipping brought fire ants to the US and
上世纪三十或四十年代 海运将火蚁带到了美国
they’ve spread across the southern states.
它们已经席卷了美国南部各州
Alabama officials are warning of something that, to me is straight out of a nightmare…
亚拉巴马州官员正警告一种 对我来说 简直是直接从噩梦中走出来的生物…
It’s a pile of fire ants clustered together to survive.
这是一群为了生存集聚在一起的火蚁
Now, you can find this invasive species
现在 你可以在像亚特兰大这样城市
alongside roads in cities like Atlanta
的路边找到这种入侵物种
easy access for the researchers at Georgia Tech
这对佐治亚理工学院的研究人员来说很方便
who’ve done pretty much anything you could think to do
他们已对火蚁做了很多
to a colony of fire ants and still call it science.
你所能想到的研究 但仍然称之为科学
David Hu: We fed ants iodine which is radioactive…
我们给火蚁喂食具有放射性的碘
flash freezing this with liquid nitrogen…
然后用液氮对其进行速冻
And then an elastic band to the waist of another ant…
然后用一根弹力绳绑住另一只的腰
and then you coat them in gold.
再在他们身上涂上金色
But that’s just standard.
不过这只是标准操作
They’ve created mathematical models to describe the ants behavior
研究人员用数学模型来描述火蚁的行为
and they characterize the ant balls as a “viscoelastic material.”
然后将火蚁组成的球称为 “粘弹性材料”
which means they have properties of both a fluid and a solid.
这意味着它们同时具有液体和固体的特性
David Hu: So they’re a solid in that they’re elastic, so for example,
由于它们是具有弹力的固体 例如
if I take a spring, you squish it, it’ll give you back the energy.
就好像挤压一根弹簧时 弹簧会将能量反弹
But they also act like a viscous fluid when under stress
但火蚁在受到压力时 还与一种粘稠的液体相似
breaking and reforming links to dissipate energy
它们宛如缓慢流动的液体
in a way that resembles a slow flow.
通过断开和重新形成连接 来消散能量
David Hu: And that’s basically how fluids work.
这基本上也就是液体流动的原理
They have very small and weak bonds everywhere
它们在各处都有着非常细小和微弱的连结
like water has these hydrogen bonds.
就像水中那些氢键一样
It’s because the bonds can break and reheal really easily.
由于氢键既易断裂 又易重新形成
You can see this happening when they’re dropped in water.
当它们被扔进水中时 你就能看到这种情况了
Within a few minutes, they’ve spread out like a drop of dye.
在几分钟内 它们就像染料那样扩散开
In their study of the towers that fire ants build after floods
在对洪水后火蚁建造的塔状建筑的研究中
Hu’s team found that the ants release their links
Hu的团队发现 当压力值超过火蚁体重
when the stress is more than 2-3 times the weight of an ant.
二至三倍时 火蚁就会松开彼此的连接
That’s when they transition from solid to fluid behavior.
这也是它们从固态变成液态的时候
They’re not sure why the ants build these towers
他们尚不确定火蚁为何要建这样的塔
but it may have to do with the fact that
但这可能与火蚁连接
the ants are more water repellent when they’re linked together.
在一起时更具防水性有关
which is how they stay afloat during a flood.
这也是它们在洪水中能漂浮的原因
David Hu: They link their bodies so closely together they actually generate a weave
它们把身体连接得非常紧密 确实是形成了某种编织物
like a waterproof fabric.
就好像防水纤维一样
So air bubbles actually have to do work to escape.
它们之所以能够脱险 实际是气泡发挥了作用
The ants aren’t drowning because they can get air from those bubbles.
火蚁没被淹死是因为它们能从气泡中呼吸空气
What’s so incredible about swarming animals is that
集群动物不可思议的是
there’s no leader directing the colony
它们当中并没有首领来
to do this.
领导它们这样做
And that sort of decentralized, collective action may be a model for future technologies.
这种去中心化的集体行为也许会成为未来科技的一种模型
David Hu: Modular robotics has been the dream of roboticists.
模块化机器人一直是机器人专家的梦想
And they’re still working on it
他们仍在朝这个方向努力
but these ants have had a couple million years and robotics has only been around for 40
但是这些火蚁已经存在了数百万年 而机器人只存在了四十年
so I think robots that do act like a fluid and like a solid
所以我觉得机器人也可以做到既像固体也像液体
I’m hoping that this work will inspire more people to pursue that kind of thing.
我希望这项研究能启发更多人去追求这个目标