Cuttlefish Remember the What, When, and Where of Meals -- Even Into Old Age (arstechnica.com) 24
According to a new paper published in the Proceedings of the Royal Society B, cuttlefish appear able to recall the time and place of their meals -- and their capability doesn't decrease as they get older. Ars Technica reports: This latest study focuses on whether cuttlefish have some form of episodic memory -- the ability to recall unique past events with context about what happened, where it happened, and when it happened. Human beings develop this capability around age 4, and our episodic memory declines as we advance into old age. That's in contrast to "semantic memory," our ability to recall general learned knowledge without the context of space and time. Semantic learning in humans has been shown to remain relatively intact with advancing age.
Cuttlefish lack a hippocampus, but they do have their own distinctive brain structure and organization, complete with a vertical lobe that shows similarities to the connectivity and function of the human hippocampus -- i.e., learning and memory. Past studies have shown that cuttlefish are sufficiently future-oriented that they can optimize foraging behavior and can remember details of what, where, and when from past forages -- hallmarks of episodic-like memory -- adjusting their strategy in response to changing prey conditions. But does that ability remain constant with age? [Co-author Alexandra Schnell of the University of Cambridge] et al. developed a series of semantic and episodic memory tests for cuttlefish to explore that question. The relatively short life span of cuttlefish (about two years) makes them an excellent candidate for this research.
For the experiments, Schnell and her colleagues used 24 common cuttlefish, half of which were young (between 10-12 months old) and half of which were old (22-24 months, apparently the equivalent of a human's 90 years). All had been reared from eggs at the Marine Biological Laboratory and were kept in individual tanks. The team first trained the cuttlefish to respond to visual cues (the waving of black and white flags) by marking specific locations in their respective tanks. As in Schnell's prior work on delayed gratification, the cuttlefish could choose their preferred prey -- in this case, either live grass shrimp or a piece of prawn meat of equal size. Over the next four weeks, the cuttlefish were taught that these two types of prey were available at specific locations (marked by the waving of the flags) after delays of either one hour (for the prawn meat) or three hours (for the preferred grass shrimp). The two feeding locations were unique for each day in order to ensure that the cuttlefish weren't merely learning a pattern. Surprisingly, Schnell et al. found that all the cuttlefish, regardless of age, were able to note which type of prey appeared first at each flagged location and were able to use that observation to figure out where to find their preferred prey at each subsequent feeding. Earlier this year, researchers found that cuttlefish could pass a cephalopod version of the famous Stanford marshmallow test: waiting a bit for their preferred prey rather than settling for a less desirable prey. "Cuttlefish also performed better in a subsequent learning test -- the first time such a link between self-control and intelligence has been found in a non-mammalian species," adds Ars.
Cuttlefish lack a hippocampus, but they do have their own distinctive brain structure and organization, complete with a vertical lobe that shows similarities to the connectivity and function of the human hippocampus -- i.e., learning and memory. Past studies have shown that cuttlefish are sufficiently future-oriented that they can optimize foraging behavior and can remember details of what, where, and when from past forages -- hallmarks of episodic-like memory -- adjusting their strategy in response to changing prey conditions. But does that ability remain constant with age? [Co-author Alexandra Schnell of the University of Cambridge] et al. developed a series of semantic and episodic memory tests for cuttlefish to explore that question. The relatively short life span of cuttlefish (about two years) makes them an excellent candidate for this research.
For the experiments, Schnell and her colleagues used 24 common cuttlefish, half of which were young (between 10-12 months old) and half of which were old (22-24 months, apparently the equivalent of a human's 90 years). All had been reared from eggs at the Marine Biological Laboratory and were kept in individual tanks. The team first trained the cuttlefish to respond to visual cues (the waving of black and white flags) by marking specific locations in their respective tanks. As in Schnell's prior work on delayed gratification, the cuttlefish could choose their preferred prey -- in this case, either live grass shrimp or a piece of prawn meat of equal size. Over the next four weeks, the cuttlefish were taught that these two types of prey were available at specific locations (marked by the waving of the flags) after delays of either one hour (for the prawn meat) or three hours (for the preferred grass shrimp). The two feeding locations were unique for each day in order to ensure that the cuttlefish weren't merely learning a pattern. Surprisingly, Schnell et al. found that all the cuttlefish, regardless of age, were able to note which type of prey appeared first at each flagged location and were able to use that observation to figure out where to find their preferred prey at each subsequent feeding. Earlier this year, researchers found that cuttlefish could pass a cephalopod version of the famous Stanford marshmallow test: waiting a bit for their preferred prey rather than settling for a less desirable prey. "Cuttlefish also performed better in a subsequent learning test -- the first time such a link between self-control and intelligence has been found in a non-mammalian species," adds Ars.
Amazing (Score:3)
I remember, too, when and where I had cuttlefish for lunch.
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They'll let us know, later.
The good news is that it appears we humans were able to pass the flag placement test in the first place.
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I buy dried cuttlefish from the Asian market. They're eaten as a tasty snack.
I usually eat them on the sofa watching TV. Just make sure you finish the packet within a few days of opening it or the cuttlefish gets soft and soggy. Of course, if you have it, it's usually gone in a single sitting.
And that's really how I eat my cuttlefish. I have never eaten cuttlefish during a meal, only as a snack.
Some o these critters (Score:2)
There seems to be a lot more thinking going on in the cephalopods than about half of humanity
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Honestly when Humans eventually stupid our species into the fossil record, something innevitable if we don't seriously start thinking about how we run our affairs, I half suspect the next species off the rank to achieve human like sapience, and maybe even succeed where we failed, and go and do the whole star trek thing, might well be a squid of some sort. Either that or one of the parrots, although I kind of feel that their lack of hands is a limiting factor there. But squids can manipulate things, seem to
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I've become convinced that humans don't have a huge brains because that make us *smart*; I think what those brains give us is *behavioral diversity*, spreading our species' evolutionary bets over a wide variety of sometimes dumb, but mostly neither here-nor-there choices.
Our huge brains won't stop us from destroying our civilization, but when we do some of us will survive living off the grid in out-of-the-way places *because that's what they prefer*. Then they're bound to have children in the next generati
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Thanks for the insightful comment on behavioral diversity.
I don't know what a cuttlefish is... (Score:2)
Yeah, it's only *literally how a brain works*! (Score:1)
All input flows through the strongest neural pathways, causing actions.
By flowing through it, it alters the strengths of the pathways it passes and misses, by strengthening the correlating ones, in space as well as in time. In other words, it forms memories. The bigger the difference from the expected input, the stronger the alteration.
But by flowing through it, the input itself is also altered, based on the current state of those neurons and pathways. (Which explains why "unbiased" is always and without ex
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P.S.: I noticed a pattern in brain research: People often look at a too high level. They treat mere artifacts of the actual, fundamental mechanisms, as if they were fundamental mechanisms. That's why you see all those terms like "episodic memory" or trying to locate certain features in certain places in the brain. (The brain is perfectly able to place those features in other places in the brain, as people have shown, who lacked that part. Like birth defects or even after injuries. It's just that in the norm
Ia Ia Cthulhu ftaghn (Score:2)
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Even death may diet.
What's baffling is ... (Score:2, Interesting)
... that biologists assume that all animals are some kind of mindless automata. Seriously, how could the things they found _not_ be true?
Where could their research go if they began with something like, "Assuming cuttlefish have episodic memory then we should be able to observe that they ...."
Having no first principles to work with, biologists are not scientists. They are simply curious observers repeatedly surprised by what they observe. What's bad is that they speak like scientists and are regarded as s
Re: What's baffling is ... (Score:2)
They are simply curious observers repeatedly surprised by what they observe.
"Let's try poking animals in the butt with a stick and see what happens."
"Anyone seen Bob recently? He was looking for a tiger."
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Having no first principles to work with, biologists are not scientists. They are simply curious observers repeatedly surprised by what they observe. What's bad is that they speak like scientists and are regarded as scientists.
I have to agree. I'm constantly bemused by biology "news" to which my response is "yes, I already knew that because I have seen actual animals in the real world and it's bloody obvious".
Darwin used to find these people annoying too.
Even Into Old Age (Score:2)
able to recall the time and place of their meals
Denny's
24 months is not "old" (Score:3)
There's an assumption that because an animal lives 2-4 years that this somehow magically makes a year a very long time. It doesn't, it's still just a year.
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The length of a year has nothing to do with an animal being "old". It has to do with the deterioration that begins in the final stages of a lifespan. An animal's capability to remember something (including us) obviously gets much worse as you reach these stages of development. So remembering something up to or even into your old age is a significant thing.
Same bullshit said in a different order.
All you're saying is that "as 90 years is to a human, 4 years is to a cuttlefish" and implying a linear, one-to-one equivalence.
"An animal's capability to remember something (including us) obviously gets much worse as you reach these stages of development"? Why is it obvious? Do you even know what cuttlefish generally die from in captivity? Is it the same things that old humans die of? Is it related to brain-function? Do 90 year old humans find it especially hard to r
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The more interesting question is: why do cephalopods have relatively short life spans, even in captivity?
Cuttlefish for president! (Score:2)
Don't have to worry about term limits.
Good for them (Score:2)
I for sure, cannot anymore, I'm too old.