Study after study confirms the unexpectedly high intelligence of rats. Besides conditioning and other simple forms of learning, they have shown us advanced abilities like empathy, episodic memory, or the recognition that a task is difficult, or metacognition. In some respects, they are like small primates. Also they have a lot of motor dexterity unexpected for a small mammal like using their hands to hold and modify their food. They have a rich social life, so they are used for psychological tests. Sometimes they remind me of small humans. It is also well-known how crafty they are and able to get in dwellings, storage places etc by ingenious ways, and moreover pet rat owners describe their animals as miniaturized dogs, a compliment I rarely hear about other small mammals. Yet their brain is too small, smooth, and not particularly different from the other rodents of their size. Where are there uncharacteristically high abilities seated? How can they accomplish so many things with a smallish brain? Is it possible that similarly sized mammals are equally intelligent but not studied? And why do they need so high intelligence, if they are preyed upon by everyone and live short lives? Intelligence is mostly advantageous in slow-maturing, k selected species.
I am going to guess that most of it is just Instinct and not intelligence.
I’ve owned pet rats for over 12 years, and they are definitely very intelligent animals. They can learn quite complex tricks and they can solve problems. Blithely labeling their behavior “instinct” doesn’t explain anything.
I can’t answer the OP questions, but I would point out that brain size doesn’t correlate directly with intelligence. For example, this article mentions that dogs have brains 30% smaller than wolves of the same size, but I doubt anyone would suggest that dogs are significantly less intelligent that wolves.
–Mark
Brain scientist here.
I am going to say that rats have a little bit of everything, but less than primates. You can find more or less the analog of most monkey brain regions in a rat. However, monkeys perform more complex tasks and accordingly brain studies in monkeys show more complex patterns of neuronal activity.
Also, I would not say that rats have a lot of dexterity. They can’t really control individual fingers.
So I agree that rats are very intelligent; and indeed intelligence is not directly related to brain size. But they are still move primitive than monkeys are certainly much more than humans.
Another point is that rats are social animals and very adaptable. Therefore they interact well in humans and make great pets.
Also, keep in mind that you can do a lot of things with few neurons. For instance, bees navigate well and communicate with each other.
You know how they say people only use 10% of their brains? I sublease the other 90% to rats.
That’s actually the answer to the OP’s question, right there.
Well, I meant that you don’t have an exact formula between brain size and intelligence. But having a big brain still helps.
Yes, undoubtedly any monkey is smarter than a rat. And despite my love of rats, it’s clear to me that dogs are smarter than rats. On the other hand, I’m not sure whether rats or cats are more intelligent. Rats are more trainable than cats, and are more social, and my impression is that many rats interact with people better than most cats do.
As far as dexterity goes, it’s true that rats don’t use individual fingers, but they do pick up things with their front paws and manipulate them, something that neither dogs nor cats do.
–Mark
Of course there’s somebody here who would suggest dogs are less intelligent than wolves … there’s a well received theory out there that says the domesticated dog is just a very stupid wolf … as the wild wolves raided the Cro-Magnon rubbish heaps all the smart wolves ran off while the stupid ones sat there and looked stupid … the bottom of the gene pool is who made themselves available for domestication.
Something I’ve observed in my pets birds, with relatively small brains, is that what they do well they do extremely well, flight is a good example. However, what they don’t do well they are really really bad at. How I noticed this is when I’m mowing with my rider. The mower doesn’t move like a predator so my birds didn’t recognize it as a threat. I’d have to stop and get off to chase the damn things away or they’d just let me run them over. I know, I tried it once, boy did I feel bad after …
Sure, birds have small brains, but what little tissue there is happens to be very highly evolved, just very specialized.
To the OP, I’m thinking there’s some confirmation bias going on here. Rats seem intelligent because they are intelligent in a very similar way as humans are. Rats and humans are surprisingly closely related, so it figures their behaviors are so much alike it’s easy to confuse their intelligence. So when looking through the eyes of the massively egotistic humans, rats would seem intelligent.
I would imagine cats are more intelligent than rats simply because cats prey on rats so well.
Trainability is not necessarily an indicator of intelligence levels either. Cats simply don’t see the percentage in performing on command. They are not as food driven as dogs or rats, and pleasing their owners is not a priority for them. To cats, pleasing their owners is nice, but they aren’t going to go out of their way to do it.
I reckon it’s more a matter of efficiency than size, analogous to how your smartphone is magnitudes more powerful than those old hulking vacuum tube computers of yesteryear while small enough to fit in your dungarees.
I think thas more to do with the physical toolset they have, rather than intelligence. Any moron with a machine gun is going to beat Einstein with a knife.
–Mark
Yeah, considering mosquitoes kill more humans than any other animal.
I know a man who has spent considerable time living near and studying wolves. One of his statements: “If you think of a wolf as a sort of uncommonly intelligent dog, you haven’t begun to comprehend the real nature of this animal.”
After all, elephants have larger brains that humans, but are not, as far as we know, more intelligent.
Here’s an interesting popular science post on the topic:
NeuWrite West -- Ask a Neuroscientist: Does a bigger brain make you smarter?
Encephalization quotient - Wikipedia
A better metric than absolute brain size is either a) ratio of brain weight to body weight or b) ratio of higher brain areas like neocortex to the total brain. “Higher” animals also have a much more folded cortex than its size in the skull belies. Rats’ brains are comparatively more smooth.
Thank you and the other posters for the answers. I must have clarified a bit more my initial post. I expected to recieve the answer that brain size alone does not define intelligence, and I wasn’t asking exactly that. I was asking something different, why animals with similar brain size to a rat aren’t as intelligent as rats. Why rabbits, although larger, aren’t rats for example. Or hamsters, or guinea pigs, which seem the stupidest from all above. Most of the rat-sized mammals are like they evolved to avoid getting eaten. Very alert to danger and quick to react. Rats on the other hand can modify this tendency a lot, even when facing humans. I have read that in poor neighboughrhoods rats become so bold, that they will climb on sleeping humans and steal their food, or even gnaw on humans. No other smallish mammal would dare to do that. Rats are also capable swimmers, diggers and climbers, and they can find a sneaky travelling root very easily. They test a new food before they eat it rutinely, to prevent poisoning. They have complex dominance and playing behaiviors like little carnivorans. No rabbit for example would turn belly up for fun. Their mating is also more complicated than even in more intelligent animals. And their birthing process is ridiculously long for a small mammal that supposedly faces predators constantly. I have read that a rat takes 120 minutes to give birth, but a rabbit only 12. How they have the luxury for so much time? Mothers also can manage unusually large litters and they can also be sensitized to young by constant exposure, even if not pregnant. Rabbits never get sensitized. Not all of the above are signs of intelligence, and many are just instincts, but even if they are instincts they must have some space in the brain, and a rat’s brain isn’t markedly larger compared to rodents its size. That was my initial question. Rabbits are not like that. I am comparing rats with rabbits, because I have a rabbit. You could put guinea pigs or other similar mammals in the same place.
Bottom line: rats seem too “evolved” I know the word is wrong for their size and place in the food chane. Either they have a so muched reduced predation pressure compared to like-sized mammals, that allows their intelligence to show, or they are significantly more intelligent than other small mammals.
ps. Not moving individual fingers isn’t something common in animals. I think only monkeys have that ability due to well-developed corticospinal tract. Do other animals have that ability as well?
They’re even more clever than that. True, if presented with a new food, a rat will eat a very small amount and stop, and wait for a while before eating any more, as if to test it for poison. However, if the rat smells the food on another rat’s breath, then it will happily eat a new food, as if reasoning “it didn’t kill him, so it won’t kill me”.
–Mark
I can say from experience that birds of the parrotiae-family/classification (and likely others) are VERY talented with their individual ‘fingers’ for various tasks they are doing. Its neat watching a bird like a cockatoo. toucans, Afr Greys, etc, solve a puzzle - like getting a treat out from a multi-‘doored’ object its never seen before that has to be opened in a certain series of moves/steps. Or even just picking the ‘meat’ out of a pecan without removing much of the shell by using one ‘finger’ to dig stuff out. My Umbrella cockatoo even learned, by watching, how to use a key (which I gave him once as a test and to win a bet) to open a padlock I had on his cage. He’d seen me do it enough that he knew the gist and applied that to the actual chore. Got it first try! He even figured out how to overcome two standard-style cage-locks at once - each foot holding open the ‘disks’ that had to be held up and his beak to slide over the spring-loaded latch that was supposed to stay closed on its own. Plus, it would use an individual ‘finger’ to clean its nasal openings and/or beak or simply to scritch itself somewhere or even work on opening his new pin-feathers. Very, very adept at control of each ‘finger’/tow/talon whenever wanted.
Birds are typically very underestimated in their intelligence, depending on how it is defined, of course. I’d bet that Kayaker would agree as I am pretty sure he has an African Grey himself, and sure he has similar experiences with his bird(s?)…
I am pretty sure 'coons can move indicidual fingers as well, but not saying it as fact, just an old observation, IIRC.
Yes I happened to find a study when searching about the corticospinal tract that compared birds with dextrous digits like parrots with birds with non-dextrous digits, but found no difference in the descending pathways to the spinal chord. They might have a different plan of their nervous system, eg recruiting older brain areas for more complex functions rather than growing the cortex at the expense of that areas like in mammals.