Despite their small brains—ravens are just as clever as chimps

April 26, 2016, Lund University
A raven. Credit: Helena Osvath / Lund University

A study led by researchers at Lund University in Sweden shows that ravens are as clever as chimpanzees, despite having much smaller brains, indicating that rather than the size of the brain, the neuronal density and the structure of the birds' brains play an important role in terms of their intelligence.

"Absolute is not the whole story. We found that corvid birds performed as well as great apes, despite having much smaller brains", says Can Kabadayi, doctoral student in Cognitive Science.

Intelligence is difficult to test, but one aspect of being clever is inhibitory control, and the ability to override animal impulses and choose a more rational behaviour. Researchers at Duke University, USA, conducted a large-scale study in 2014, where they compared the inhibitory control of 36 different animal species, mainly primates and apes. The team used the established cylinder test, where food is placed in a transparent tube with openings on both sides. The challenge for the animal is to retrieve the food using the side openings, instead of trying to reach for it directly. To succeed, the animal has to show constraint and choose a more efficient strategy for obtaining the food.

The large-scale study concluded that great apes performed the best, and that absolute brain size appeared to be key when it comes to intelligence. However, they didn't conduct the cylinder test on corvid birds.

Can Kabadayi, together with researchers from the University of Oxford, UK and the Max Planck Institute for Ornithology in Germany, therefore had ravens, jackdaws and New Caledonian crows perform the same cylinder test to better understand their .

The team first trained the birds to obtain a treat in an opaque tube with a hole at each end. Then they repeated the test with a transparent tube. The animal impulse would naturally be to go straight for the tube as they saw the food. However, all of the ravens chose to enter the tube from the ends in every try. The performance of the jackdaws and the crows came very close to 100%, comparable to a performance by bonobos and gorillas.

A raven. Credit: Helena Osvath / Lund University

"This shows that bird brains are quite efficient, despite having a smaller absolute brain size. As indicated by the study, there might be other factors apart from absolute brain size that are important for intelligence, such as neuronal density", says Can Kabadayi, and continues:

"There is still so much we need to understand and learn about the relationship between intelligence and brain size, as well as the structure of a bird's , but this study clearly shows that bird brains are not simply birdbrains after all!"

A raven. Credit: Helena Osvath / Lund University

Explore further: Researchers figure out similarities in brain architecture between birds and apes

More information: Can Kabadayi et al, Ravens, New Caledonian crows and jackdaws parallel great apes in motor self-regulation despite smaller brains, Royal Society Open Science (2016). DOI: 10.1098/rsos.160104

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TheGhostofOtto1923
2.4 / 5 (19) Apr 26, 2016
Huh. I wonder if either species has 'consciousness', whatever that is. Perhaps only the smarter ones do. Perhaps only the ones that have names like Koko or Birdy Mcbirdface do. Or the ones that humans teach to do tricks.

Perhaps only the ones that seek revenge on humans for past trespasses, like in that movie where Richard Harris killed that orca's pregnant mate.

Did the white whale have consciousness before Chris Hemsworth stuck it with a harpoon but after Gregory Peck stuck it with a harpoon?

Do humans plant the seed of consciousness in animals by interacting with them? Are domesticated animals born with consciousness?

Are these questions that need answering I wonder?
MaxC500
4.6 / 5 (9) Apr 26, 2016
That's funny. Since most humans would try to go strait for the food. And only after minutes of moaning, puffing and screaming would finally come to the right conclusion to obtain the food.

I will look to ravens with greater respect from now on.
HeloMenelo
3.2 / 5 (13) Apr 26, 2016
at least antigoracle's got a bird brain, pitty he only uses 1/4th of it though
JongDan
4.6 / 5 (9) Apr 26, 2016
Birds are superior to mammals in many aspects; besides the obvious flight thing, they also have way more efficient respiratory system.
Zorcon
3.5 / 5 (8) Apr 26, 2016
...most humans would try to go strait for the food. And only after minutes of moaning, puffing and screaming would finally come to the right conclusion to obtain the food.

LOL, and many humans would rather use a hammer than think about it...
Zorcon
3.5 / 5 (11) Apr 26, 2016
"Despite their small brains—ravens are just as clever as chimps"

Pity we can't say the same about some of the trolls attracted to words like "evolution", "climate" and "cosmology."
Protoplasmix
2 / 5 (6) Apr 26, 2016
@Ghost, why should nature select things, and why has it made a long series of selections to produce (so far) us? You seem to think it's all clockwork, and so you miss the part that recognizes the clockwork and wonders why. And when that part reaches out and changes where the hands on the clock face would otherwise have pointed, you complain about wasting time.
sascoflame
5 / 5 (3) Apr 27, 2016
No matter who gets studied it turns out they are smarter than people . They are smarter then the smart animals too.
stardner
1.7 / 5 (6) Apr 27, 2016
How does this study prove the cleverness of birds? From what I've seen in wild birds, they often have to pick through obstacles to obtain food, whether it be birdseed, prey in a hollow, or trash... made all the more difficult from the lack of hands. Isn't this behavior moreso instinctual brain circuitry than general intelligence?
Whydening Gyre
5 / 5 (8) Apr 27, 2016
How does this study prove the cleverness of birds? From what I've seen in wild birds, they often have to pick through obstacles to obtain food, whether it be birdseed, prey in a hollow, or trash... made all the more difficult from the lack of hands. Isn't this behavior moreso instinctual brain circuitry than general intelligence?

It's the fact that crows (ravens) will employ other objects as "tools" to aid in that picking, that makes the difference.
antialias_physorg
5 / 5 (7) Apr 27, 2016
The team first trained the birds to obtain a treat in an opaque tube with a hole at each end. Then they repeated the test with a transparent tube.

There's a tricky bit in here I'd like to see addressed in a follow up study: Does a transparent tube appear transparent to birds? I.e. is it absolutely known that their vision matches that of humans so closely? If they see any more in the UV or infrared spectrum (or polarized light) than we do then the tube may well see more 'substantial' to them than to humans (i..e the test isn't a test at all because to the bird it's no different than the opaque tube scenario).
Transparent plastic is not transparent at all wavelengths.
stezlaf
5 / 5 (4) Apr 27, 2016
I think one thing should be kept in mind while doing this particular study. Corvids have evolved along side modern human society -- in fact, flourishing through symbiosis. To their credit, these birds are very intelligent, but have also long learned about man made objects. Plastic tubes, tires, glass -- they have experience with these things. A wild bonobo, on the other hand, would most likely not have encountered these objects before. Being able to analyze a new situation without prior experience would be a true test of intelligence.
TheGhostofOtto1923
3.5 / 5 (8) Apr 27, 2016
@Ghost, why should nature select things, and why has it made a long series of selections to produce (so far) us? You seem to think it's all clockwork, and so you miss the part that recognizes the clockwork and wonders why. And when that part reaches out and changes where the hands on the clock face would otherwise have pointed, you complain about wasting time
I think this belongs in another thread?
Eikka
5 / 5 (4) Apr 27, 2016
There's a tricky bit in here I'd like to see addressed in a follow up study: Does a transparent tube appear transparent to birds?


It doesn't look exactly appear transparent to us, or the chimps either, in the same way as the surface of water is clearly distinguishable from its reflections, the little bits of dust floating on top, or from the visual distortion.

It's rather a test of perception rather than intelligence, because it takes relatively little brain power to understand that if there's something in the way you need to take a different route.

The bird brain may understand it the same as it would understand a spider's web - don't stick your head through it but go around.
Phys1
1.7 / 5 (3) Apr 27, 2016
Huh. I wonder if either species has 'consciousness', whatever that is. Perhaps only the smarter ones do. Perhaps only the ones that have names like Koko or Birdy Mcbirdface do. Or the ones that humans teach to do tricks.

Perhaps only the ones that seek revenge on humans for past trespasses, like in that movie where Richard Harris killed that orca's pregnant mate.

Did the white whale have consciousness before Chris Hemsworth stuck it with a harpoon but after Gregory Peck stuck it with a harpoon?

Do humans plant the seed of consciousness in animals by interacting with them? Are domesticated animals born with consciousness?

Are these questions that need answering I wonder?

This may answer your questions:
https://www.faceb...0374632/
moebiex
1.4 / 5 (5) Apr 27, 2016
Doesn't information theory posit that the amount of information transmitted increases (exponentially maybe even) with the frequency of the carrier waves. That leads toi the questions: what frequencies do the bird brains run at?
compose
Apr 27, 2016
This comment has been removed by a moderator.
antialias_physorg
4.2 / 5 (5) Apr 27, 2016
Doesn't information theory posit that the amount of information transmitted increases (exponentially maybe even) with the frequency of the carrier waves.

No it doesn't.

That leads toi the questions: what frequencies do the bird brains run at?

Erm...whut? How does that first statement about the CARRIER wave lead to the second one?
Whydening Gyre
5 / 5 (5) Apr 27, 2016
Doesn't information theory posit that the amount of information transmitted increases (exponentially maybe even) with the frequency of the carrier waves.

No it doesn't.

That leads toi the questions: what frequencies do the bird brains run at?

Erm...whut? How does that first statement about the CARRIER wave lead to the second one?

Think he was going for "density of signal as a predictor of number of thoughts" paradigm.
In reality, it usually just means more noise....
Whydening Gyre
5 / 5 (5) Apr 27, 2016
I don't know about frequency of brain, but many birds are able to distinguish individual frames even at the 60 FPS video - the high visual cortex processing speed undoubtedly contributes to high neuron density of bird's brains.

That one would require corroborating research...
The insects like dragonfly can achieve even better temporal resolution: 200 FPS.

Because there is a large network of simpler optical processors (due to number of eye facets)combining input to a simpler neural network (less energy expenditure)
arrayist2
5 / 5 (5) Apr 27, 2016
This tells us that dinosaurs were probably not stupid because they had small brains as Paleontologists have long asserted. Many dinosaurs walked on two legs like birds, had feathers like birds, saw with four color receptors like birds, digested food with gizzards like birds, had hip joints like birds, were fast moving like birds, possessed side facing eyes like birds, laid eggs like birds, built nests like birds, raised young like birds, flocked like birds, were warm blooded like birds, were often multicolored like birds, made many sounds like birds, had acute hearing like birds, possessed elaborate visual displays like birds and existed in nearly every niche on earth like birds.

Would this not then clearly suggest they had more intelligence than brain size would indicate just like birds do? Isn't it time then for paleontology to update its old fashioned assumptions about lumbering stupid dinosaurs?

A small brain may simply be more efficient rather than less effective,
TehDog
5 / 5 (7) Apr 27, 2016
Ok, anecdote time. A few years ago, early spring I think, I watched a magpie and crow play "follow the leader" in a tree. The magpie could fly through the branches, the crow had to hop and flap. They were silent, no alarm calls, and the crow took a breather in the adjacent field for a coupla minutes while the magpie waited in the tree. They weren't contesting a nesting site or a feeding station, just having fun.
I also get to see ravens showing off their flying skills to prospective mates, terrible show offs they are :)
torbjorn_b_g_larsson
5 / 5 (5) Apr 28, 2016
Bees are in some respects even more amazing. Some million neurons, but can display complex behavior (bee dances) and learn continuously (have different tasks depending on age, and improve task efficiency as they do it).

And arguably a bee hive display a collective consciousness (is aware of its surroundings due to bee dances).

The intelligence question seems backwards, even fishes can be tool users. (Use rocks to smash open clam shells.) The question may instead be, why are so few species at the high end of intelligence? Seems general intelligence is useful, high intelligence only when the surrounding is complex and you food search is patchy.
Protoplasmix
3.7 / 5 (3) Apr 28, 2016
I think this belongs in another thread?
It belongs exactly in this one. It's 100% on-topic and addresses your questions about consciousness; questions you still apparently have, despite all the things others took time point out to you in many other threads related to the topic. And I get three 1s while you get three 5s – it looks an awful lot like Noumenon was accurate with respect to intellectual honesty. But I won't ignore you.

If you allowed yourself even a basic definition of consciousness, like simply "awareness", then even single cells appear to have consciousness. If you agree that computer hardware/software is an extension of human consciousness then you have some really difficult questions to answer – but you're still stuck on "whatever that is" and "do these questions need answers" … okayeiii
TheGhostofOtto1923
3 / 5 (6) Apr 28, 2016
Mr hissy
It belongs exactly in this one. It's 100% on-topic and addresses your questions about consciousness; questions you still apparently have, despite all the things others took time point out to you in many other threads related to the topic. And I get three 1s while you get three 5s – it looks an awful lot like Noumenon was accurate with respect to intellectual honesty. But I won't ignore you
Sorry your comment didn't obviously relate to my post.

And I've taken great pains to show that there is no useful def of consciousness. This is why serious researchers don't use the word in their work beyond being an attention-getter.

And I've shown that many, like dennett, have concluded that it is an illusion.

No evidence, no utility, no definition, no consensus... no existence. No matter how special you glorious human beings think you are.
TheGhostofOtto1923
3 / 5 (6) Apr 28, 2016
"Consciousness is the state or quality of awareness, or, of being aware of an external object or something within oneself. It has been defined as: sentience, awareness, subjectivity, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind [snicker]. Despite the difficulty in definition, many PHILOSOPHERS believe that there is a broadly shared underlying intuition about what consciousness is [and many more don't have a clue]."

"broadly shared underlying intuition..." -WTF is that?

"sentience, awareness, subjectivity, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind..."

-Well which is it? Is it either/or or and/if? Is it the sum of percentages plus a fudge factor?

There is no definition here. And claiming they just haven't found it yet IN NO WAY is evidence that it EXISTS.

You understand that don't you?
TheGhostofOtto1923
3 / 5 (6) Apr 28, 2016
-And THIS

"In medicine, consciousness is assessed by observing a patient's arousal and responsiveness, and can be seen as a continuum of states ranging from full alertness and comprehension, through disorientation, delirium, loss of meaningful communication, and finally loss of movement in response to painful stimuli..."

-is an outright lie. Being conscious, as opposed to being unconscious, is awareness. It has nothing to do with the consciousness that philos and priests are so fond of.

To illuminate, there is no medical or physiological test that can assess the relative consciousness of a person and a dog. You might be able to measure sentience as some sort of threshold, as it refers to function, but there is not even a working def of this concept.
TheGhostofOtto1923
3 / 5 (6) Apr 28, 2016
THIS

"To most philosophers, the word "consciousness" connotes the relationship between the mind and the world. To writers on spiritual or religious topics, it frequently connotes the relationship between the mind and God, or the relationship between the mind and deeper truths that are thought to be more fundamental than the physical world."

-is what doesn't exist. The realm 'below the bottom of the pond' where all the bullshit settles.

What is mind? What is world? Philos actually think these are valid questions. They love to imply that there are useful answers to these questions, which supplies them with endless opportunity to fiddle with them.

And that was only the first sentence of the above excerpt.

'Deeper truths'. Anybody want to field that one?
rhugh1066
5 / 5 (3) Apr 28, 2016
Whoa, Otto, calm down brother. Is consciousness one of those, "them's fightin' words" for you?
While it appears to be nothing more - boy, what an understatement - than a byproduct function of a brain, it seems we won't know til we manage to construct devices with whatever degree of complexity are necessary to generate it. If that line of reasoning is even correct. Since I'm firmly in the camp that fears the downside of AI, I dread the day we accomplish that goal.
TehDog
4.4 / 5 (7) Apr 28, 2016
Very late edit, I said " ...ravens showing off their flying skills...". They were rooks, don't think I've ever seen a raven in the wild.
Protoplasmix
4 / 5 (4) Apr 28, 2016
To illuminate, there is no medical or physiological test that can assess the relative consciousness of a person and a dog.
Is there any fMRI data on dogs yet? How about electroencephalography for providing a rudimentary assessment of brain activity? Even easier, have you never observed a dog running in its sleep while dreaming? What do you suppose it was conscious of? Maybe it wasn't dreaming if consciousness is meaningless. Maybe it was just quickly resting.

My first post belongs exactly here, too, after all that...
TheGhostofOtto1923
3.4 / 5 (5) Apr 29, 2016
While it appears to be nothing more - boy, what an understatement - than a byproduct function of a brain
WHAT is? Do you have any idea what IT might be? Any evidence whatsoever that there is such a thing?

Or are you willing to use the word without thinking about it just because everybody else does?
Is there any fMRI data on dogs yet? How about electroencephalography for providing a rudimentary assessment of brain activity?
Well there's plenty for humans. Show me a study which has found a thing in humans which fits the philo definition of consciousness that I referred to.

You know, this

"To most philosophers, the word "consciousness" connotes the relationship between the mind and the world. To writers on spiritual or religious topics, it frequently connotes the relationship between the mind and God, or the relationship between the mind and deeper truths that are thought to be more fundamental than the physical world."

Take your time.
TheGhostofOtto1923
3.4 / 5 (5) Apr 29, 2016
That thing that philos take for granted, and waste time and money writing books about, because they have a 'broadly shared underlying intuition..." that it's there.

That thing that noumenon calls the most immediately obvious thing that ever was and ever will be.

Yeah I paraphrase, which gives him the opportunity to say he never ever said such a thing. But its close enough.

And again, I will emphasize that conscious is NOT consciousness. Dog and human 'minds' are not exploring any realm beyond the physical, or conversing with god, when they dream.

There are far more mundane processes at work when our brains continue to function while we are asleep.

Do you think dogs believe in astral projection as well?
rrrander
3.7 / 5 (3) May 01, 2016
Humans have a sad, lonely need to anthropomorphize animals. Disney did it and more than a few gullible Americans have paid for this belief with their lives. The latest being an animal trainer who got killed by the tiger. Animals are instinct-driven, period.
Phys1
1 / 5 (1) May 01, 2016
@rrander
That is just an instinctive reaction, period.
Protoplasmix
5 / 5 (1) May 01, 2016
And again, I will emphasize that conscious is NOT consciousness.
You feel strongly about that. As if crazy is not craziness and English is not English. But feelings and semantics hardly constitute scientific rigor. You're clearly aware (conscious) of a "process" because you characterize it as "mundane," so how can you then dismiss it as something merely philosophical when it so obviously has real physiological attributes?

Please don't cherry-pick quotes from philosophers. And don't complain about a lack of scientific rigor if you refuse to apply any.

cont'd >
Protoplasmix
not rated yet May 01, 2016
cont'd >

Dog and human 'minds' are not exploring any realm beyond the physical ...
I can't speak for dogs, or even other humans so much, but I can relate a personal experience that no amount of semantics will counter: After racking my brain for days I went to bed one night frustrated about not being able to see an underlying equation regarding prime numbers (a subject quite abstract, or quite 'beyond the physical'). I awoke the next morning, and while looking at my chicken scratches, still in a fog of sleepiness, I thought, "well, it has to be this –" and I proceeded to effortlessly write it down, without any trouble at all. Where in my head, without any scratch paper whatsoever, did I come up with it?
TheGhostofOtto1923
2.2 / 5 (10) May 01, 2016
@Mr hissy
You feel strongly about that. As if crazy is not craziness and English is not English
Yeah because I looked it up. Perhaps you could educate yourself as I am not going to copy/paste the dictionary because I don't feel like it.
I thought, "well, it has to be this –" and I proceeded to effortlessly write it down, without any trouble at all. Where in my head
So you discovered that your brain continues to work while asleep.

What do you think you are arguing about?

I'm sorry I'm having trouble taking you seriously. Have you heard this before? Here? From others? In so many words?
gkam
3 / 5 (10) May 01, 2016
"Yeah because I looked it up."

http://www.thegua...n-google
kochevnik
1 / 5 (4) May 01, 2016
@Ghost Do humans plant the seed of consciousness in animals by interacting with them? Are domesticated animals born with consciousness?
Quantum channels in brain microtubules are necessary for consciousness. There is no study yet, but I doubt only humans have this biology. Since this "wetware" manifests at a very basic level in molecular biology, I would suspect consciousness is ubiquitous
kochevnik
1 / 5 (5) May 01, 2016
@jljenkins Since you downvote established science news, could you share your insights? Or are you simply out of your element, trolling this board?
jljenkins
3 / 5 (10) May 01, 2016
I don't dignify specious, self interested, tedious, arm chair grandiosity with serious debate.

That is trolling. Voting is not trolling. Good to hear you're irritated, though.

kochevnik
1 / 5 (5) May 01, 2016
@jljenkins I don't dignify specious, self interested, tedious, arm chair grandiosity with serious debate.

That is trolling. Voting is not trolling. Good to hear you're irritated, though.

Fine what exactly do you know about brain microtubules that the greater science community doesn't? Do share

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