Name: 動物界の「目」全種類を解説 | WIRED Japan (動物界の「目」全種類を解説 | WIRED Japan)
Uploaded: 2025-05-23T08:09:51.000Z
Duration: 36 min 25 s

Did you know that ambush predators tend to have vertical-slip pupils to better pinpoint their prey, while grazers tend to have horizontal pupils to better scan the horizon for incoming movement?

您知道嗎，伏擊捕食者的瞳孔往往是垂直滑動的，以便更好地確定獵物的位置，而食草動物的瞳孔往往是水準的，以便更好地掃描地平線，尋找來襲的動靜。

We created this tree of life that focuses on the evolution of animal eyes, and we're going to walk through it with Professor Lars Schmitz.

我們創建了這棵生命之樹，重點關注動物眼睛的進化，接下來我們將與拉爾斯-施密茨教授一起了解這棵樹。

I study vision and the evolution of eyes, and I just love everything about eyes.

我研究視覺和眼睛的進化，我喜歡有關眼睛的一切。

We'll start at the base of the tree with an early branching fork of animals called cnidaria.

我們將從樹的根部開始，先看一種叫做刺胞動物的早期分支。

The box jellyfish actually have 24 different eyes in clusters of six eyes each.

盒水母實際上有 24 只不同的眼睛，每隻眼睛由六隻眼睛組成。

One pair of these eyes in each of these clusters are not unlike our own eyes.

每個星團中的一雙眼睛與我們的眼睛並無二致。

人眼的工作原理類似於照相機。

We have the aperture, the pupil that lets the light in, behind which we have the optical system.

我們有光圈，即讓光線進入的瞳孔，瞳孔後面是光學系統。

So what we nicely see here is the curved corneal, the optical apparatus in front of the eye, and the second optical element, the lens.

是以，我們在這裡看到的是彎曲的角膜、眼睛前方的光學儀器以及第二個光學元件--晶狀體。

Those together refract light onto the retina and forms an image.

這些光線一起折射到視網膜上，形成影像。

To stay with a camera analog, this would be where the film would be, or the receptors.

如果使用模擬攝影機，這裡就是膠片或感受器的位置。

Cubizones are really interesting in that they don't have a centralized nervous system.

Cubizones 非常有趣，因為它們沒有中樞神經系統。

They have a nerve net, which allows them to process visual stimuli, but they don't have a real brain.

它們有神經網，可以處理視覺刺激，但沒有真正的大腦。

So it's actually really puzzling how they can actually interpret those visual signals.

是以，它們是如何解讀這些視覺信號的著實令人費解。

From here, the tree of life has a major divergent path.

從這裡開始，生命之樹出現了重大的分叉。

We'll follow first the site of the protostomes, which includes insects and many deep sea animals.

我們首先要了解的是原生動物，包括昆蟲和許多深海動物。

They actually have dozens of eyes around their mantle.

實際上，它們的外殼周圍有幾十隻眼睛。

Every single blue dot you see in this image, these little blueberries, those are eye structures.

你在這張圖片中看到的每一個藍點，這些小藍莓，都是眼睛的結構。

This ring of blueberry eyes is actually useful for them as a defensive mechanism and a little bit of a navigation help.

實際上，這圈藍莓眼對它們很有用，既是一種防禦機制，又能幫助它們導航。

The way the scallops form images in their little blueberry eyes is very different from what we do.

扇貝在藍莓小眼睛裡形成影像的方式與我們截然不同。

It has a mirror that's sitting behind the retina, and that mirror is used to focus the light back onto the retina.

視網膜後面有一面鏡子，這面鏡子用於將光線聚焦到視網膜上。

So it's a really complicated mechanism, but it works well enough to get you an image of the scenery.

是以，這是一個非常複雜的機制，但它能很好地為你提供景物的影像。

The resolution is really not that good, but scallops can actively move.

分辨率確實不高，但扇貝會主動移動。

So they can visually navigate to an extent.

是以，他們可以在一定程度上進行視覺導航。

And also when they see something approaching, they can shut down and close down and protect themselves.

另外，當它們看到有東西靠近時，它們就會關閉和封閉起來，保護自己。

Let's look at a few examples of eyes from some cephalopods.

讓我們來看看一些頭足類動物眼睛的例子。

The pinhole eye of the nautilus works just like the pinhole camera and has a very small opening through which light enters, and then an inverted image is formed on the retina.

鸚鵡螺的針孔眼的工作原理與針孔照相機一樣，它有一個很小的開口，光線從這個開口進入，然後在視網膜上形成倒像。

So let's take a look at the human eye model here.

讓我們來看看這裡的人眼模型。

我們基本上去掉了所有的光學器件。

Light's coming in from right here, and then the image, as crude as it is, falls directly onto the retina.

光線從這裡射入，然後影像，儘管很粗糙，卻直接落在視網膜上。

The smaller the pupil, the better the resolution of the resulting image.

瞳孔越小，生成影像的分辨率越高。

But the issue there is if you make the pupil really small, the image will be dimmer and dimmer the smaller the pupil is.

但問題是，如果把瞳孔做得非常小，瞳孔越小，影像就會越來越暗。

They do have a central nervous system to process visual information.

它們確實有處理視覺資訊的中樞神經系統。

Actually a little bit of a mystery what exactly they're using that eye for.

實際上，他們到底用那隻眼睛做什麼，還是個謎。

The image will be a little bit dim, so it's kind of limited in what it can see with that eye.

影像會有點暗，所以它的眼睛能看到的東西有點有限。

Octopuses have a chambered eye type, and in difference to the nautilus, this one has a lens.

八爪魚的眼睛有一個腔室，與鸚鵡螺不同的是，它有一個晶狀體。

And what we have in common here is this deep eye cup.

A pupil that's really well defined, that's the only part where light can enter the eye and nowhere else.

瞳孔的輪廓要非常清晰，這是光線唯一能進入眼睛的地方，其他地方都不行。

If light from all directions could enter the eye, we wouldn't know where it's coming from.

如果來自四面八方的光線都能進入眼睛，我們就不會知道光線來自哪裡。

One really important difference between octopuses and our own eye.

章魚和我們的眼睛有一個非常重要的區別。

The photoreceptors are actually pointing away from the light.

光感受器實際上是遠離光線的。

And the axons that transmit the signal approach the incoming light.

而傳輸信號的軸突則靠近射入的光線。

But in octopuses, the retina is the other direction with the photoreceptors pointing towards the incoming light and the axons going away.

但在章魚中，視網膜的方向是相反的，光感受器指向射入的光線，而軸突則向遠方。

The side effect of the inverted retina that we have, the so-called blind spot in the retina where we do not have any photoreceptors.

我們所擁有的倒置視網膜的副作用，即視網膜上沒有感光器的所謂盲點。

So in this model, we can see the optic nerve really clearly right here.

在這個模型中，我們可以清楚地看到視神經。

So this is where all the axons from the photoreceptors are bundled together and exit the eye and transmit the signal off to the brain.

光感受器的所有軸突都在這裡匯聚成束，並從眼球中流出，將信號傳輸到大腦。

But in this part right here, where the axons exit, that's where we cannot have any photoreceptors.

但是，在軸突出口的這一部分，我們不能有任何光感受器。

From my understanding, it's not really well known how exactly and what may explain that pattern.

據我所知，目前還不太清楚這種模式的確切原因和解釋。

There may be a small advantage of having the photoreceptors a little bit further back.

光感受器靠後一點可能會有一點好處。

The resolution of the image may be a tiny little bit better.

影像的分辨率可能會好一點點。

Personally, I'm not sure if that's a huge reason that would provide additional evolutionary fitness.

就我個人而言，我不確定這是否是一個能提供額外進化適應性的巨大原因。

The bottom line is our retina, even though it's inverted, it works well enough.

最重要的是，我們的視網膜雖然是倒置的，但也能很好地工作。

One thing that's really interesting about squid is their cool pupil shapes.

烏賊最有趣的一點是它們酷酷的瞳孔形狀。

If we just look at squid, here are two examples.

如果我們只看烏賊，這裡有兩個例子。

在你的右邊，你會看到這個 U 形。

On the left, we have this W shape in here.

The function of these pupil shapes is a little bit of a mystery.

這些瞳孔形狀的功能有點神祕。

And a really interesting hypothesis in this context is color vision.

在這種情況下，一個非常有趣的假設就是顏色視覺。

Color vision in squid is not well supported behaviorally, but it would make sense given that they use colors for signaling, for example.

烏賊的顏色視覺在行為學上並沒有得到很好的支持，但考慮到烏賊利用顏色來傳遞信號，這也是有道理的。

In humans, in our own color vision, we use three different opsin types, so three different photopigments to distinguish different colors.

在人類的色覺中，我們使用三種不同的視蛋白類型，即三種不同的光敏色素來分辨不同的顏色。

是以，我們有紅色、綠色和藍色。

Depending on the strength of the relative excitation of these pigments, we can infer what color wavelength we're actually looking at.

根據這些色素的相對激發強度，我們可以推斷出所看到的顏色波長。

In squid, we don't have different opsin types.

在烏賊中，我們沒有不同的視蛋白類型。

The image would be essentially a grayscale image.

How can they see color if they only have one opsin type?

如果只有一種視蛋白，它們怎麼能看到顏色？

Many animals correct an optical problem, chromatic aberration.

許多動物都能糾正色差這一光學問題。

Chromatic aberration results from the fact that shorter wavelength light is refracted more strongly than longer wavelength light.

色差產生的原因是波長較短的光比波長較長的光折射更強。

If you have blue light versus red light, the blue light would be focused a little bit before the retina and the red light a little bit behind the retina.

如果是藍光和紅光，藍光會聚焦在視網膜前一點，紅光會聚焦在視網膜後一點。

Now this is something that most animals actually try to get rid of.

現在，大多數動物其實都想擺脫這種東西。

There's the hypothesis that these pupils actually accentuate the chromatic aberration.

有一種假設認為，這些瞳孔實際上會加重色差。

And they can use that to tell what color light they're actually looking at.

他們可以利用這一點來判斷自己看到的究竟是什麼顏色的光。

This blur hypothesis is a bit controversial in our community.

這個模糊假說在我們的社區有點爭議。

Some people say, while theoretical, possibly the practical benefit isn't all that big.

有人說，雖然理論上是這樣，但實際好處可能並不大。

The key will be to test how these animals perceive colors and if there's good behavioral evidence to find out.

關鍵是要測試這些動物是如何感知顏色的，以及是否有良好的行為證據來找出答案。

As we head back through the tree of life, let's stop to talk about the flatworm.

當我們穿過生命之樹往回走時，讓我們停下來談談扁形蟲。

This little fellow has two very conspicuous eyes right here.

這個小傢伙有兩隻非常顯眼的眼睛。

These are very simple eyes, like little eye spots.

這些眼睛非常簡單，就像小眼斑。

What we see here is eyes that are really not good from our perspective, but are beneficial to this aquatic flatworm.

在這裡，我們看到的是一雙在我們看來並不好的眼睛，但對這隻水生扁形蟲來說卻是有益的。

Essentially, it would help them to avoid getting eaten.

從根本上說，這可以幫助它們避免被吃掉。

These eyes are consisting of just two cell types.

They have photoreceptors in a shallow cup.

So light can only reach these eye cups from above and a little bit from the side.

是以，光線只能從上方和側面照射到這些眼罩。

But it cannot reach the eye cup from below because that's where the pigmented cells are.

但它無法從下方到達眼杯，因為色素細胞就在那裡。

This flatworm would be able to tell if it's in bright versus dark environments.

這種扁形蟲可以分辨出它所處的環境是明亮還是黑暗。

And it would know if the light is coming from directly above or perhaps a little bit from the side.

它還能知道光線是從正上方照過來的，還是從側面照過來的。

Now that seems like utterly useless to us.

現在看來，這對我們毫無用處。

But for this flatworm, it's good to know like it's bright, it's exposed, it's in the dark, it's perhaps a bit protected.

但對於這條扁形蟲來說，知道它是明亮的、暴露在外的、在黑暗中的、也許受到一點保護的，這是件好事。

Now let's cover the other fork of the protostomes, which include insects, spiders, and some other arthropods.

現在讓我們來介紹原生動物的其他分叉，包括昆蟲、蜘蛛和其他一些節肢動物。

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動物界の「目」全種類を解説 | WIRED Japan (動物界の「目」全種類を解説 | WIRED Japan)

essentially

evolve

slip

ability