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I'm a neuroscientist, and I'm the co-founder of Backyard Brains,
我是一名神经科学家，我也是Backyard Brains的共同创办人，
and our mission is to train the next generation of neuroscientists
我们的使命是要训练下一代的神经科学家，
by taking graduate-level neuroscience research equipment and making it available for kids in middle schools and high schools.
做法是把研究所等级的神经科学研究设备开放给初中和高中的孩子使用。
And so when we go into the classroom, one way to get them thinking about the brain, which is very complex,
我们进到教室，使学生思考复杂头脑的方式之一是，
is to ask them a very simple question about neuroscience, and that is, "What has a brain?"
问他们一个非常简单的神经科学问题，那就是：“什么有头脑？”
When we ask that, students will instantly tell you that their cat or dog has a brain,
当我们问这个问题，学生会马上告诉你，他们的猫或狗有头脑，
and most will say that a mouse or even a small insect has a brain,
大部分人会说，老鼠、甚至小昆虫也有头脑，
but almost nobody says that a plant or a tree or a shrub has a brain.
但几乎没有人会说植物、树木或灌木有头脑。
And so when you push -- because this could actually help describe a little bit how the brain actually functions
当你再进一步--因为这其实可以稍微协助描述头脑实际上如何运作，
so you push and say, "Well, what is it that makes living things have brains versus not?"
所以当我们再进一步问说：“生物有没有头脑的差别在哪？”
And often they'll come back with the classification that things that move tend to have brains.
通常，他们回答的分类是会动的生物通常有头脑。
And that's absolutely correct. Our nervous system evolved because it is electrical.
那完全正确。我们的神经系统是用电的，所以会进化。
It's fast, so we can quickly respond to stimuli in the world and move if we need to.
它很快，所以我们能对世界上的刺激物做出快速反应，有需要我们也会移动。
But you can go back and push back on a student, and say,
但你可以回头去再问学生：
"Well, you know, you say that plants don't have brains, but plants do move."
“你说植物没有头脑，但植物确实会动。”
Anyone who has grown a plant has noticed that the plant will move and face the sun.
只要你曾经种过植物，就会注意到植物会动，它会面向太阳。
But they'll say, "But that's a slow movement. You know, that doesn't count. That could be a chemical process."
但他们会说：“但那是很缓慢的移动，不算数。那可能是种化学过程。”
But what about fast-moving plants?
那动得很快的植物呢？
Now, in 1760, Arthur Dobbs, the Royal Governor of North Carolina, made a pretty fascinating discovery.
1760年，北卡罗来纳的皇家总督亚瑟·杜伯斯有个非常棒的发现。
In the swamps behind his house, he found a plant that would spring shut every time a bug would fall in between it.
在他家后面的沼泽中，他发现一种植物，每次只要有一只虫落入它中间，它就会飞快阖上。
He called this plant the flytrap, and within a decade, it made its way over to Europe,
他把这植物称为捕蝇草，十年内，它就散播到了欧洲，
where eventually the great Charles Darwin got to study this plant, and this plant absolutely blew him away.
最终伟大的查尔斯·达尔文得以研究这种植物，这植物完全让他惊呆了。
He called it the most wonderful plant in the world.
他称之为世界上最美妙的植物。
This is a plant that was an evolutionary wonder.
这种植物是演化上的奇迹。
This is a plant that moves quickly, which is rare, and it's carnivorous, which is also rare.
这种植物动的速度很快，这点很稀有，且它是肉食性的，这点也很稀有。
And this is in the same plant. But I'm here today to tell you that's not even the coolest thing about this plant.
同一种植物有两种稀有特性。但今天，我要告诉各位，这还不是这植物最酷的事。
The coolest thing is that the plant can count.
最酷的事是植物能计数。
So in order to show that, we have to get some vocabulary out of the way.
要展现这一点，我们得要先解决一些词汇的意思。
So I'm going to do what we do in the classroom with students.
我打算用我们在教室里教学生的方式。
We're going to do an experiment on electrophysiology,
我们要做一个电流生理学实验，
which is the recording of the body's electrical signal, either coming from neurons or from muscles.
也就是记录身体的电信号，可能来自神经元或肌肉。
And I'm putting some electrodes here on my wrists.
我要在我的手腕贴上电极。
As I hook them up, we're going to be able to see a signal on the screen here.
等我把它们弄好，我们就会看到信号出现在屏幕上。
And this signal may be familiar to you. It's called the EKG, or the electrocardiogram.
你可能觉得这信号很熟悉。它叫EKG，或心电图。
And this is coming from neurons in my heart that are firing what's called action potentials,
这来自我心脏的神经元，这些神经元会发射所谓的动作电位，
potential meaning voltage and action meaning it moves quickly up and down,
电位就是电压，动作就表示它快速上下动，
which causes my heart to fire, which then causes the signal that you see here.
造成我的心脏反应，产生出你们在这里看到的信号。
And so I want you to remember the shape of what we'll be looking at right here, because this is going to be important.
请各位记住我们在这里看到的形状，这点之后会很重要。
This is a way that the brain encodes information in the form of an action potential.
这是头脑把信息编码成动作电位的一种形式。
So now let's turn to some plants. So I'm going to first introduce you to the mimosa,
现在，我们来看一些植物。我要先向各位介绍含羞草，
not the drink, but the Mimosa pudica, and this is a plant that's found in Central America and South America, and it has behaviors.
不是含羞草调酒，是含羞草植物，在中美和南美可以找到这种植物，它是有行为的。
And the first behavior I'm going to show you is if I touch the leaves here, you get to see that the leaves tend to curl up.
我要展示的第一个行为是，当我触碰叶子，你们可以看到叶子会缩起来。
And then the second behavior is, if I tap the leaf, the entire branch seems to fall down.
第二个行为是，如果我轻敲叶子，整个分枝都会向下倒。
So why does it do that? It's not really known to science.
它为什么要这样做？科学还没有答案。
One of the reasons why could be that it scares away insects or it looks less appealing to herbivores.
原因之一可能是它想把昆虫吓跑，或比较不会吸引到食草动物。
But how does it do that? Now, that's interesting. We can do an experiment to find out.
但它怎么做到的？这就很有趣了。我们可以做个实验来找出答案。
So what we're going to do now, just like I recorded the electrical potential from my body,
我们现在要做的，就像是我记录我身体的电位一样，
we're going to record the electrical potential from this plant, this mimosa.
我们要记录这含羞草的电位。
And so what we're going to do is I've got a wire wrapped around the stem, and I've got the ground electrode where?
我们要做的是，用电线包住茎的部分，把接地电极接到哪里呢？
In the ground. It's an electrical engineering joke. Alright.
地上。这是个电子工程师笑话。好了。
Alright. So I'm going to go ahead and tap the leaf here,
好。我要轻敲这里的叶子，
and I want you to look at the electrical recording that we're going to see inside the plant.
请各位注意看等下会出现来自植物的电信号记录。
Whoa. It is so big, I've got to scale it down. Alright. So what is that?
哇。好大，我得要缩一下比例。好了。那是什么？
That is an action potential that is happening inside the plant.
那是行动电位，且是在植物内部发生的。
Why was it happening? Because it wanted to move. Right?
它为什么会发生？因为它想要动，对吗？
And so when I hit the touch receptors, it sent a voltage all the way down to the end of the stem, which caused it to move.
所以当我去触碰接收器，它会发送电压，一路向下送到茎的底端，使茎动了。
And now, in our arms, we would move our muscles, but the plant doesn't have muscles.
在我们的手臂中，我们会动肌肉，但植物没有肌肉。
What it has is water inside the cells and when the voltage hits it,
它的细胞中有水分，当电压接触到它时，
it opens up, releases the water, changes the shape of the cells, and the leaf falls.
它会打开，放出水分，改变细胞的形状，叶子就会倒下。
OK. So here we see an action potential encoding information to move. Alright? But can it do more?
所以，在这里我们看到了行动电位能够将信息编码来造成移动。对吧？但它能做更多吗？
So let's go to find out. We're going to go to our good friend, the Venus flytrap here,
我们来找出答案。我们要来找我们这里的好朋友，捕蝇草，
and we're going to take a look at what happens inside the leaf when a fly lands on here.
我们要来看一下，当一只苍蝇降落在这里时，叶子里会发生什么事。
So I'm going to pretend to be a fly right now.
现在，我要假装是一只苍蝇。
And now here's my Venus flytrap, and inside the leaf,
我的捕蝇草在这里，看一下叶子内部，
you're going to notice that there are three little hairs here, and those are trigger hairs.
有三根毛在这里，它们是感觉毛。
And so when a fly lands -- I'm going to touch one of the hairs right now. Ready? One, two, three.
所以当苍蝇降落，我现在要来触碰其中一根毛。准备好了吗？一、二、三。
What do we get? We get a beautiful action potential. However, the flytrap doesn't close.
我们得到了什么？很漂亮的行动电位。然而，捕蝇草没有阖上。
And to understand why that is, we need to know a little bit more about the behavior of the flytrap.
要了解为什么会这样，我们需要多了解一点捕蝇草的行为。
Number one is that it takes a long time to open the traps back up
第一，把陷阱重新打开要花的时间很长，
you know, about 24 to 48 hours if there's no fly inside of it. And so it takes a lot of energy.
如果没有苍蝇在里面的话，大约要24到48小时，那要花很多的能量。
And two, it doesn't need to eat that many flies throughout the year.
第二，一整年间，它并不需要吃那么多苍蝇。
Only a handful. It gets most of its energy from the sun.
少量即可。它大部分的能量来自太阳。
It's just trying to replace some nutrients in the ground with flies.
它只是试着以苍蝇取代一些地面的营养物。
And the third thing is, it only opens then closes the traps a handful of times until that trap dies.
第三，它只能将陷阱开阖少数几次，然后陷阱就会死亡。
So therefore, it wants to make really darn sure that there's a meal inside of it before the flytrap snaps shut.
因此，它要非常确定有餐点在陷阱里面的时候，它才会快速阖上。
So how does it do that? It counts the number of seconds between successive touching of those hairs.
它怎么做到的？它会计算秒数，连续触碰那些毛之间的时间间隔。
And so the idea is that there's a high probability, if there's a fly inside of there, they're going to be quick together,
概念是，如果里面有苍蝇，它就非常可能会阖上，
and so when it gets the first action potential, it starts counting, one, two,
所以当它接到第一个行动电位时，它就开始计算，一、二，
and if it gets to 20 and it doesn't fire again, then it's not going to close,
如果数到二十都不再有电位发出，它就不会阖上，
but if it does it within there, then the flytrap will close.
但如果有的话，捕蝇草就会阖上。
So we're going to go back now. I'm going to touch the Venus flytrap again.
我们要再回来。我要再次触碰捕蝇草。
I've been talking for more than 20 seconds.
我已经讲话超过二十秒了。
So we can see what happens when I touch the hair a second time.
来看看当我二度触碰这根毛时会发生什么事。
So what do we get? We get a second action potential, but again, the leaf doesn't close.
我们得到什么？第二个行动电位，但同样的，叶子没有阖上。
So now if I go back in there and if I'm a fly moving around, I'm going to be touching the leaf a few times.
如果我再回来，如果我是一只到处跑的苍蝇，就会再触碰叶子几次。
I'm going to go and brush it a few times. And immediately, the flytrap closes.
我要再轻轻拂过它几次。马上，捕蝇草阖上了。
So here we are seeing the flytrap actually doing a computation.
我们看到捕蝇草真的在计算。
It's determining if there's a fly inside the trap, and then it closes.
它判断是否真的有苍蝇在陷阱中，然后才阖上。
So let's go back to our original question. Do plants have brains? Well, the answer is no.
所以，我们回到原先的问题。植物有头脑吗？答案是没有。
There's no brains in here. There's no axons, no neurons.
这里面没有头脑。没有轴突、没有神经元。
It doesn't get depressed. It doesn't want to know what the Tigers' score is.
它不会沮丧。它不会想知道底特律老虎队目前得几分。
It doesn't have self-actualization problems.
它没有自我实现的问题。
But what it does have is something that's very similar to us, which is the ability to communicate using electricity.
但它有和我们很相似之处，就是用电来沟通的能力。
It just uses slightly different ions than we do, but it's actually doing the same thing.
只是它用的离子和我们有些微不同，但做的事是一样的。
So just to show you the ubiquitous nature of these action potentials,
只是要让大家看看这些行动电位无所不在的特性，
we saw it in the Venus flytrap, we've seen an action potential in the mimosa.
我们在捕蝇草身上看到了，我们在含羞草身上看到了。
We've even seen an action potential in a human.
我们在人类身上看到了。
Now, this is the euro of the brain. It's the way that all information is passed.
这就是头脑的欧元，是让所有信息得以传递的方式。
And so what we can do is we can use those action potentials to pass information between species of plants.
我们能利用那些行动电位在不同种的植物之间传递信息。
And so this is our interspecies plant-to-plant communicator,
这是我们的跨物种植物对植物的沟通器，
and what we've done is we've created a brand new experiment where we're going to record the action potential from a Venus flytrap,
我们创造了一个全新的实验，从捕蝇草这里记录行动电位，
and we're going to send it into the sensitive mimosa.
接着把它传送给敏感的含羞草。
So I want you to recall what happens when we touch the leaves of the mimosa.
请各位回想一下，当我们触碰含羞草叶面时会发生什么事。
It has touch receptors that are sending that information back down in the form of an action potential.
它的触碰接收器会向下传送行动电位形式的信息。
And so what would happen if we took the action potential from the Venus flytrap and sent it into all the stems of the mimosa?
所以，若我们把捕蝇草的行动电位传送到含羞草的茎内会发生什么事？
We should be able to create the behavior of the mimosas without actually touching it ourselves.
我们应该会在不用自己触碰含羞草的情况下就引发含羞草的行为。
And so if you'll allow me, I'm going to go ahead and trigger this mimosa right now by touching on the hairs of the Venus flytrap.
所以，如果可以的话，我现在就要来触碰捕蝇草的毛，来触发含羞草的行为。
So we're going to send information about touch from one plant to another.
我们将会把触碰一棵植物的信息传送到另一棵植物。
So there you see it. So...
看到了吧。所以...
So I hope you learned a little bit, something about plants today, and not only that.
所以我希望各位今天学到了一点关于植物的知识，且不只如此。
You learned that plants could be used to help teach neuroscience and bring along the neurorevolution. Thank you.
你们学到了植物能被用来协助教导神经科学，并能带来神经革命。谢谢。
