These Slugs See with Their Brains

If you’re a person with sight, your two eyes are your only window into the visual world. But slugs see not only with their eyes, but with their brains as well!

Hosted by: Stefan Chin

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[UGNAvalon]

Slug Brain in a Jar: “I do not need eyes, for my mind possesses _True_ sight!”

[DigitalMonsters]

"if you love slugs" .... then sorry about the whole cutting off their eyes thing.

[ratatataraxia]

I just started keeping a European leopard slug in my terrarium. So this is cool that we are still learning about them.

[himanbam]

Slugs: Man I can see pretty good because I have eyes.

Scientists: Mm yes but what if you didn't.

Slugs: What

[believer]

One of the most beautiful creatures I've seen in my life. I'm fascinated by them.

[SpaceEngineerErich]

I would have replaced the phrase 'in vertebrates' with 'among vertebrates' to make the point clearer that he didn't mean invertebrates.

[PigRipperLAW]

“If you like slugs”

You’re gonna have a bad time. 🐌

[LeesaDeAndrea]

They cut their eyes off?! I know they're just slugs, but jeez! Couldn't they think of a less cruel way?

[DylanMatthewTurner]

What makes something "part of the brain?"

Like if our eyes are directly connected to the brain through the optic nerves, right? Well then technically they're part of the brain. Or we can go the other way. Why aren't the hippocampus and cerebellum considered separate organs since they have different functions from each other?

Could you argue that the light-receptive cells on the snail's brain that contain the protein are a form of primitive eyes and not part of the brain?

I realize this could come off as pedantic, which is not my intent. I genuinely want to know how do scientists decide where one organ ends and one begins?

[marcopohl]

science denier: How would the eye evolve? what good is half an eye?
slug: hold my opsin

[garrett]

My first AI robot was along these lines. I had heard the evolution of eyes started with a fishbwith two light sensitive patches of skin.
So I made my robot learn that it could recharge (feed) itself in bright sun using photo transistors as eyes.

[isnanesavant]

its crazy to think that creatures can reach a point of seeing without eyes. It sounds so unreal but ay, here we slug

[Gjonesy]

The Blind Messiah
*All Hail the Great, Slug*

[Niinkai]

According to the paper (second link in the sources), the slugs were under anesthesia when the surgical procedures were performed, and were put down with anesthesia before being dissected.

[Bearded-Logic]

Why not cover their eyes instead of cutting them off?

[PresidentSunday]

"Where we're going, we won't need eyes to see"

[BadMadChicken]

Looks like i have more in common with slugs than previously thought. Neat.

[masteryoshi]

That's how Piccolo can see without looking.

[traceantonacci]

I can see with my brain, too. You don't see me bragging about it.

[greythehunter]

Is this what they mean by “Eyes on the inside"