What a crab sees before it gets eaten by a cuttlefish | Hacker News Reader

What a crab sees before it gets eaten by a cuttlefish

nytimes.com

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Gift link with video, because a static archive doesn't do the opening video justice:

https://www.nytimes.com/2025/03/03/science/cuttlefish-camouf...

Thanks! I didn't realize the static archive was missing the video. These are better than what's on Santon's site.

Damn that was quick the attack

reminds me of Nope

Here the link to the mp4 file (from my InternetDownloadManager)

https://vp.nyt.com/video/2025/03/03/135038_1_03tb-cuttlefish...

There are 4 videos in the article, each with different forms of predatory approach.

It's very neat.

Using the above gift link as argument to yt-dlp, you can download all four videos in one fell swoop. If you want to just watch the four videos and not read the article.

  yt-dlp --add-metadata "https://www.nytimes.com/2025/03/03/science/cuttlefish-camouflage-huting-crabs.html?unlocked_article_code=1.1U4.y9tH.Aujw5YLUNl3v&smid=url-share"

  [NYTimesArticle] Extracting URL: https://www.nytimes.com/2025/03/03/science/cuttlefish-camouflage-huting-crabs.html?unlocked_artic...UNl3v&smid=url-share
  [NYTimesArticle] cuttlefish-camouflage-huting-crabs: Downloading webpage
  ERROR: [NYTimesArticle] cuttlefish-camouflage-huting-crabs: Unable to download webpage: HTTP Error 403: Forbidden (caused by <HTTPError 403: Forbidden>)

Maybe you have to update yt-dlp, or maybe the link has been used by too many people? For me it worked.

Hmm, for Firefox on Android, the videos animate once and then stop, still-framed forever. Ditto in desktop mode. Weird.

Time to go over to a real computer I guess.

Works fine on Brave

They don't play on Chrome for Android, either.

Works for me on Chrome for Android

The playback was broken on Firefox android from both the main site and direct url here as well, but was able to watch the video correctly after downloading it locally.

I appreciate the gift but I suspect sleep tonight will be less than appreciative.

I don’t think the crabs are confusing their prey so much as paralyzing them with fear

*cuttlefish

Why not post the OP with this link?

Defector did it better (and included the videos): https://defector.com/this-is-the-last-thing-you-see-before-y...

Defector is fantastic and Sabrina Imbler is an absolute treasure - gift link, to share the wealth: https://defector.com/this-is-the-last-thing-you-see-before-y...

I find cuttlefish normally very cute but dear god this is nightmare fuel.

This article is so much better than the original NYT one. Great writing and no paywall.

How the hell is this news site loading so fast, with no popups, nag screens, in-body ads, call-to-actions and autoplaying videos? Jesus, since when do we have the technology to achieve that?!

In Peter Watts' novel Blindsight, human protagonists enter a completely alien world - not Star Trek "people with rubber ears", but different biology/consciousness-patterns/etc entirely.

As one of the plot points, 'aliens' (again, not the Star Trek humanoid kind) eventually 'hack' the human nervous/visual systems through various means (electromagnetic fields, visual patterns, movement types, etc) to hide things in plan sight.

My internal vision of scenes from that book is eerily similar to the videos in the article.

(On aside, would highly recommend Peter Watts to Hacker News audience :)

Seconded. Blindsight remains one of my favorite meditations on the Mind's I (not a typo) that I've read.

Echopraxia, the 'sequel' (the events occur at the same time as the events in Blindsight, with a completely different group of characters) has grown on me over time, too. At the very least, it gave me a great appreciation for Portia. https://en.wikipedia.org/wiki/Portia_(spider)

Isn't that what Children of Time by Tchaikovsky is for? :)

Ha! Good point. No argument there.

Same! Echopraxia did not really resonate on the first read, and I think it was misaligned expectations. As Peter himself said in one of his Reddit AMAs, it starts with action and continues with a lot of action.

But it's fundamentally not about action; in fact, it's hard to see the protagonists having much agency, and certainly no clear goals. It's almost existential in that sense; but based on that beginning, my mind was searching for a story and hero and conclusion.

On the second read, having the framework of the events in my mind, I could focus on the ideas, and it resonated much better. Now I re-read both books semi-regularly (just like Dune and Neuromancer:)

Yep! I'm glad to hear that someone else had the same misaligned initial expectations. Keeping it vague to avoid spoilers, but the fact that I'm still unsure if the protagonist's action at the very end of the story was an example of agency or not has been a lot of fun to think about.

Same thing with the Expanse series. The TV version captured Ilus very well I think, and some of the creatures with a completely different biology. Especially the terrifying idea of something as simple as some algae type stuff that ends up making everyone blind for a certain time, because why wouldn't our eyes be an attractive for alien microorganisms.

The deceptive capabilities of cuttlefish has been known since ancient Greece. The 2C AD author of hunting and fishing books Oppian wrote extensively about the 'cunning devices' of cuttlefish, as well as octopuses, which he considers to be par excellennce foxes of the sea.

  Yea, the crafty Cuttle-fish also has found a cunning manner of
  hunting. From her head? grow long slender branches, like locks of
  hair, wherewith as with lines she draws and captures fish, prone in
  the sand and coiled beneath her shell.
  
  They have seated in their heads a dark muddy fluid blacker than pitch,
  a mysterious drug causing a watery cloud, which is their natural
  defence against destruction. When fear seizes them, immediately they
  discharge the dusky drops thereof and the cloudy fluid stains and
  obscures all around the paths of the sea and ruins all the view ; and
  they straightway through the turbid waters easily escape man or haply
  mightier fish. ... Such are the cunning devices‘ of fishes.

What amazing creatures! One of the coolest experiences I’ve lived scuba diving was an interaction with a cuttlefish. It would come towards me in its alien like swimming style and crazy eyes, while pulsating super cool colors, getting very close to my face and then quickly swimming back and forth and up and down, speeding up and slowing down, like performing some kind of ritual dance.

I think it was trying to hypnotize me, like Futurama’s good old Hypnotoad. What was the motivation behind, I will always wonder

The colors understanding is even more remarkable given that they are colorblind in the sense that they do not have different color cones, and likely rely on a very imperfect process of chromatic aberration that they can somehow translate back into color.

https://www.science.org/content/article/how-colorblind-cuttl...

Color me impressed. Remarkable indeed, thanks for the link.

I spent 15 minutes watching a group of about 8 cuttlefish on a reef. There were clearly lots of complex group interactions going on between them. It is also amazing fast they can change colour.

Perhaps it was saying "So long, and thanks for all the fish?"

Or 42 in Cuttlefishish

Crabs predate cuttlefish in the fossil record by a significant amount of time (~50 million years), but both have had a good 100 million years to battle it out and crabs are still blinded by the camo. Cuttlefish maybe have not exerted enough evolutionary pressure on crabs to make them adapt, or there are crabs that have adapted and we just don't know which species or have not discovered them yet.

They could be at an evolutionary equilibrium already.

Somehow, predators succeed in many scenarios that have plenty of time for evolution to solve the problem for prey. But of course it's also solving the problem for hungry predators.

It raises an interesting question about the limits of evolutionary adaptation, and how the evolutionary competition reaches a stable equilibrium.

I'm not sure it's that unique of a situation though, most prey organisms have some antipredator adaptations but rarely are they foolproof, just like rarely are predatory adaptations like mimicry/camouflage/crypsis absolutely foolproof.

Its an 'arms race'. As crabs adapt to the current crop of cuttlefish ruses, the cuttlefish also adapt to overcome again.

An aside, but the recent book by Dawkins "The Genetic Book of the Dead: A Darwinian Reverie" is fascinating and explains how you can look at an animal and understand the environment of its ancestors. You can read it as a kind of massive autobiography of the species and detect waypoints on its evolutionary journey.

I was hoping the article would include a video, but there's a great 12 second clip on Matteo Santon's site: https://matteosanton.com/research/

> I was hoping the article would include a video

It has several videos.

Yep, I missed that the archive link doesn't have video.

please revisit the HN article, several sibling comments now share the videos

I’m trying to understand how/what the cuttlefish attacks the crag with - but I can’t tell if the white thing that comes out from under its… “Cthluthu mouth-tentacles” is a tongue, a beak, a bone, a pincer, a spine, or something else.

Wikipedia’s page on cuttlefish anatomy doesn’t help, unfortunately :/

Cuttlefish, like squid, have 8 short tentacles around the mouth plus other 2 much longer tentacles, which are thinner except for their ends, which are expanded and which have suckers.

The 2 long tentacles are normally kept coiled and covered by the short tentacles, so they are not visible.

When the cuttlefish catches prey, the 2 long tentacles are extended together extremely quickly and they attach to the prey (much like a chameleon catches insects with its very long tongue).

Then the 2 long tentacles are retracted quickly, bringing the prey to the mouth that is also hidden between the 8 short tentacles. The mouth has a beak, similar to a parrot beak, which is used to kill and consume the prey.

See the drawing:

https://en.wikipedia.org/wiki/Cuttlefish#/media/File:Seba_mo...

The drawing shows the long tentacles as you could see them on a dead cuttlefish. As I have said, in the living cuttlefish you can see them only for a fraction of a second, when catching prey and bringing it to the mouth.

Also, the 2 long tentacles are extended together, one besides the other, they never stay limp and separated, like in the drawing or in a dead animal.

> The drawing shows the long tentacles as you could see them on a dead cuttlefish. As I have said, in the living cuttlefish you can see them only for a fraction of a second

Yeah: stop drawing dead butterflies https://www.emilydamstra.com/please-enough-dead-butterflies/

Once you've seen the pattern, you see the same issue with other art. I bought a biology style painting because I liked the intentional dead-animal style (both a bird and some insects).

https://archive.is/qancZ

Plenty of this going on in this BBC earth video: https://youtu.be/rbDzVzBsbGM?feature=shared&t=130

Clearly this is the inspiration for the design of the mindflayers.

This was an immersive experience. I was trying to make sense of what I was seeing, putting my face closer to the screen to take a good look at the creature... Then WHACK! paywall! It hit me before I could understand what was happening.

I can relate to that crab.

Horrifying, does the video cut suddenly because what happens next is too fast for the brain to comprehend before being destroyed?

I thought when the cuttlefish starts blinking, it essentially becomes invisible to the crab

a video has nothing to do with a brain

The video is representing what a crab sees. An abrupt cut is either implying that the crab stops seeing (for brain damage reasons), or the video is not quite living up to the promise, and they are asking which it is.

They are hitting the plexiglass in front of the camera and crabs, so I assume it's nothing interesting to look at science wise.

It would be nice to see some high speed video, like the kind they use to show a bullet going through an apple.

I always reserve budget for night diving. Below the waters, night time is like peak hour traffic, with much better chances of spotting a cuttlefish. The colors they exhibit is beautiful. You can only see them at night and with a torch light as red gets filtered out even at shallow depths.

Couldn't help but be reminded of this scene from that movie where Tom Hanks plays Fred Rogers: https://youtu.be/9AzXX_2BrVk?t=63

My local aquarium has cuttlefish, I love those little guys

I did a quick search to understand how the crabs eyes work. If they see less detail then this must be even more convincing.

I would totally fall for that too....

Immediately got reminded of the creatures in Perdido Street Station -- Terrifying!

why do these videos just cut at the moment???

Cookie and subscription pop-ups?

Big Jordan Peele Nope energy.

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