Cuttlefish can count to five

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Cuttlefish should be able to count to ten, considering they have ten tentacles*. They just aren’t trying.

*Technically speaking, eight arms and two actual tentacles.


One…two…some…lots…all of them!


In the well-known documentary Watership Down, it is shown that rabbits can count up to four.* So cuttlefish have a leg up on them now! Er, tentacle.

*(no, I’m not being serious)


Obligatory cuttlefish story (because everyone has one, right?) …

I used to do a lot of scuba diving with the Australian National University dive club. We had our own boat and would be found most weekends diving the rocky reefs south of Sydney. On one weekend trip down to Jervis Bay, my good friend Ole lead a dive in the deep water outside of the bay’s entrance. They tossed the anchor into the 50 meter depths, geared up, and descended. Ole, being first down the line, had the responsibility of “setting” the anchor to make sure the boat wouldn’t be carried off by the strong current. Focused on this task he failed to see the giant cuttlefish approaching from behind. Ole looked up and the first (and last) thing he saw were large tentacles grabbing his mask and wrenching it away from his face. Water flooded into his vision and the next 20 seconds were spent blindly vying for ownership. He claims the cuttlefish had a body a meter long and, while probably a slight exaggeration, I don’t doubt the creature was a damn sight bigger than the 40-50cm ones we frequently saw in shallower water. Couple the larger size with the nitrogen narcosis and the sudden surprise and it was probably very much like a scene from Alien.


I, for one, welcome our new cuttlefish overlords.


Hopefully it’s just laziness. If it turns out that they get distracted by ruminating on primitive recursive functions and formalizing an axiomatic construction of the natural numbers; then we are going to have to feel really, really, bad about eating them.


Counting is a priori knowledge. Any cuttlefish would tell you that.


Being able to distinguish “more” from “less” is not exactly counting, even if a cute youtube guy says so.


You broke quarantine and let him back on the boat?

Next outbreak of Deep Ones is your fault.


Maybe, but what is counting, really, other than being able to distinguish more from less. Humans have the ability to do this to an extremely precise degree. Cuttlefish can distinguish between 5 items and 4 items, something the vast majority of the animal kingdom is apparently unable to do. How high can humans count? If we’re allowed to write numbers down and manipulate the objects we’re counting, I suppose we’re able to count to as large as we have the vocabulary. But without those tools, how large? I don’t think I could count 100 objects without error if I weren’t allowed to move the ones I’d already counted. So just looking at them, I could probably count somewhere between 50 and 100, depending on the size and variability in the objects being counted. And my error rate would go up as the number of items went up. Anyway, my point is, arguing whether or not this qualifies as counting is probably semantics. The point is that cuttlefish can do something we previously only thought primates and a few other animals could do.


Better than Drumpf and his ilk.


Came to this thread looking for this cartoon, was not disappointed :thumbsup:

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Well really “counting” is the ability to name numbers, not the innate ability to distinguish the number of items. Humans are actually pretty poor at the innate ability to distinguish the number of items, many vertebrates are better at it than we are. Whether this is because we CAN count or because triplets are exceedingly uncommon is an interesting question.


One and one and one and one and one. Two. No more than two.

What’s interesting to me is most cephalophods have a relatively short life span. I think cuttlefish only live a year or two, maybe three. Have to wonder how clever they’d be if they lived longer.



well, i don’t know how to speak cuttlefish, but maybe they have names for the numbers in their own, cuttlefishy way.