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Animal Intelligence Tests
Topic Started: Jan 30 2016, 05:44 AM (2,935 Views)
Ursus arctos
Autotrophic Organism

I saw two articles I thought were really cool in the last couple days, so figured I'd post them both here.

Young gorillas dismantling traps:
Bush-meat hunters set thousands of rope-and-branch snares in Rwanda's Volcanoes National Park, where the mountain gorillas live. The traps are intended for antelope and other species but sometimes capture the apes.
...


Poachers build the snares by tying a noose to a branch or a bamboo stalk, Vecellio explained.

Using the rope, they pull the branch downward, bending it. They then use a bent stick or rock to hold the noose to the ground, keeping the branch tense. A sprinkling of vegetation camouflages the noose.

When an animal budges the stick or rock, the branch springs upward, closing the noose around the prey. If the creature is light enough, it will actually be hoisted into the air.
...


On Tuesday tracker John Ndayambaje spotted a trap very close to the Kuryama gorilla clan. He moved in to deactivate the snare, but a silverback named Vubu grunted, cautioning Ndayambaje to stay away, Vecellio said.

Suddenly two juveniles—Rwema, a male; and Dukore, a female; both about four years old—ran toward the trap.

As Ndayambaje and a few tourists watched, Rwema jumped on the bent tree branch and broke it, while Dukore freed the noose.

The pair then spied another snare nearby—one the tracker himself had missed—and raced for it. Joined by a third gorilla, a teenager named Tetero, Rwema and Dukore destroyed that trap as well.


Really cool stuff!





The other:
Brain size predicts problem-solving ability in mammalian carnivores.
I attached a csv of their data, but found it extremely hard to interpret on my own:
The data is very "noisy", a huge amount of things going on you may want to (and hypothetically could) consider.

An example of what I mean:
The animals were given a puzzle box with food in it. The trick was figuring out how to open it.
A jaguar named Tizon worked on the box for 22 minutes on his first try before opening it and eating his reward. His next three tries took him about 3 minutes, 2 minutes, and then only half a minute.
That makes sense. Tizon figured out the trick.

The tiger Sevaki spent just over 4 minutes on his first try. However, after succeeding, he didn't eat his reward.
His second try took a little under 6 minutes. Again, he succeeded, but didn't eat his reward.
He failed on all three of his later attempts. Did he actually care about the food?

The black bear Jam spent a little under 15 minutes on her first try. She succeeded, but didn't eat. She failed her remaining two attempts.

Another tiger and three snow leopards also showed that sort of behavior.

But a lot of other animals did succeed on their first try, eat the reward, and then fail on later ones. How can we interpret that?
I would hesitate to attribute that to being less good at problem solving.

I also wouldn't generalize to different sorts of tasks. The social carnivores that take large prey would all probably do extremely well on tasks of cooperation, for example.


However, for a variety reasons I don't wish to cover here, I think it is best to stick to the author's analysis.
Table comparing results by families:
FamilyNo. of SpeciesRelative brain sizeTotal no. of trialsNo. of individuals testedNo. of individuals successfulIndividuals successful (%)
Ailuridae10.189184125
Canidae70.193 (-0.13 to 0.41)7525624
Felidae13-0.093 (-0.36 to 0.23)179521528.8
Herpestidae2-0.417 (-0.59 to -0.24)14500
Hyaenidae2-0.192 (-0.26 to -0.12)237228.6
Mustelidae4-0.005 (-0.37 to 0.14)8117847.1
Procyonidae30.077 (0.02 to 0.18)4213753.8
Ursidae50.196 (-0.16 to 0.94)4513969.2
Viverridae2-0.153 (-0.24 to -0.06)174125
Sum or mean394951404935


The discussion section:

The connection between brain size and cognitive abilities has been
called into question by both a study pointing out the impressive
cognitive abilities of small-brained species, such as bees and ants (7),
and another study doubting that overall brain size is a valid proxy for
cognitive ability (9). In the former case, Chittka and Niven (7) argue
that larger brains are partially a consequence of the physical need
for larger neurons in larger animals and partially caused by in-
creased replication of neuronal circuits, which confers many ad-
vantages for larger-brained species, such as enhanced perceptual
abilities and increased memory storage. Chittka and Niven (7)
conclude that neither of these properties of larger brains necessarily
enhance cognitive abilities. Interestingly, our results actually show
that carnivore species with a larger average body mass performed
worse than smaller-bodied species on the task that we presented to
them. Thus, it truly does seem that a larger brain size relative to
body size is an important determinant of performance on this task,
and it is not the case that larger animals are more successful simply
because their brains are larger than those of smaller species.
Regarding whether overall brain size is a valid proxy for cognitive
abilities, the use of whole-brain size as a predictor of cognitive
complexity in comparative studies is questioned, because the brain
has different functional areas, some of which are devoted to partic-
ular activities, such as motor control or sensory processing. Given this
high degree of modularity in the brain, Healy and Rowe (8, 9) argue
that overall brain size is unlikely to be a useful measure when ex-
amining how evolution has shaped the brains of different species
to perform complex behaviors. Although the brain has functional
modules, such as the hippocampus or the olfactory bulbs, which may
be under specific selection pressures (31), these modules may also
exhibit coordinated changes in size because of constraints on ways in
which the brain can develop (32). In addition to functionally spe-
cialized modules, the brain also contains broad areas, such as the
mammalian neocortex, that control multiple processes. Thus, there
are reasons to believe that overall brain size may be an informative
proxy for cognitive abilities, despite the modular nature of the brain.
Here we examined relationships between relative brain size, size of
specific brain regions, and problem-solving success. Although none of
the regional brain volumes that we examined significantly predicted
success on this task (Table S9), the addition of the volume of these
brain regions improved the ability of our models to explain perfor-
mance in the puzzle box task over a model containing only total brain
volume (Table 3). We emphasize, however, that only 17 species were
included in that analysis. Nevertheless, relative brain size was a sig-
nificant predictor of problem-solving success across species, and this
result was robust in all of our analyses. Thus, our data provide im-
portant support for the idea that relative brain size can be useful in
examining evolutionary relationships between neuroanatomical and
cognitive traits and corroborate results from artificial selection ex-
periments showing that larger brain size is associated with enhanced
problem solving (5). It will be important in future work to use more
detailed noninvasive brain imaging methods rather than endocasts to
evaluate whether hypothetically important brain areas, such as pre-
frontal and cingulate cortexes, contribute to the relationship between
brain size and performance during problem solving.
Assessment of the ecological and neuroanatomical predictors of
problem-solving ability has some important implications for hy-
potheses proposed to explain the adaptive value of large brains and
sophisticated cognition. One such hypothesis that has garnered
much support in primate studies is “the social brain hypothesis” (33,
34), which proposes that larger brains evolved to deal with chal-
lenges in the social domain. This hypothesis posits that selection
favored those individuals best able to anticipate, respond to, and
perhaps even manipulate the actions of conspecific group members.
However, a major shortcoming of the social brain hypothesis (35,
36) is its apparent inability to explain the common observation that
species with high sociocognitive abilities also excel in general in-
telligence (37, 38). There is, in fact, a long-standing debate as to
whether animal behavior is mediated by cognitive specializations
that have evolved to fulfill specific ecological functions or instead,
domain-general mechanisms (38, 39). If selection for social agility
has led to the evolution of domain-general cognitive abilities, then
species living in social groups should solve technical problems better
than solitary species. However, we found that carnivore species
living in social groups performed no better on our novel technical
problem than solitary species. Thus, whereas social complexity may
select for enhanced ability to solve problems in the social domain
(40), at least in carnivores, greater social complexity is not associated
with enhanced ability to solve a novel technical problem.
Our results are similar to those obtained in the work by MacLean
et al. (12), which examined relationships among brain size, social
complexity, and self-control in 23 species of primates. In both that
study and our own study, species with the largest brains showed the
best performance in problem-solving tasks. However, in neither pri-
mates nor carnivores did social complexity predict problem-solving
success. This finding is also consistent with results obtained in the
work by Gittleman (41), with analysis of 153 carnivore species that
revealed no difference in brain size relative to body size between
social and solitary species. Nevertheless, in this study, we were only
able to present carnivores with a single problem-solving task, and we
were only able to test one to nine individuals per species. Ideally,
future studies will present a large array of carnivores with additional
cognitive challenges and will test more individuals per species.
A second hypothesis forwarded to explain the evolution of larger
and more complex brains, the cognitive buffer hypothesis (42, 43),
posits that large brains evolved to allow animals to cope with
socioecological challenges and thus, reduce mortality in changing
environments. Previous work has shown convincingly that diet is a
significant predictor of brain size in carnivores (27), as it is in pri-
mates (12), and this study shows that carnivore species with larger
brains are more likely to solve a novel technical problem. However,
an explicit test of the cognitive buffer hypothesis has not yet been
attempted with mammalian carnivores.
Overall, our finding that enhanced problem solving is related to
disproportionally large brain size for a given body mass is important
for several reasons. First, although there is correlational evidence for
an association between absolute or relative brain size and problem-
solving abilities, experimental evidence is extremely rare. The lack of
experimental evidence has led to criticisms of the use of brain size as
a proxy for problem-solving abilities (8, 9, 44). We offer experimental
evidence that brain size is, indeed, a useful predictor of performance,
at least in the single problem-solving task that we posed to our
carnivore subjects. Although only brain size relative to body mass was
a significant predictor of success with our puzzle box, species with
larger absolute brain volumes also tended to be better than others at
opening the puzzle box (Figs. 2 and 3 and Table S2). Second, the vast
majority of work on this topic has focused on primates, fish, and birds
(5, 10, 11, 13–16). Our results offer new evidence for the relationship
between brain size and problem-solving abilities in mammalian car-
nivores. The previous lack of support for this relationship across a
diverse set of taxa has limited both its validity and its generality.
Thus, the findings presented here represent an important step for-
ward in our understanding of why some animals have evolved large
brains for their body size.
Attached to this post:
Attached File box_open_data.csv (76.54 KB)
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zergthe
Member Avatar
Kleptoparasite
[ *  *  *  *  *  * ]
Gorillas be like, 'kay, kids, this is how you disarm a trap. Watch me do.
---One Year Later
Vubu: Now, who can remember how to disarm a trap?
Both young gorillas: OOH, OOH, PICK ME
Vubu: There is a trap over there. Disarm it.

And so on and so forth lol
Edited by zergthe, Jan 30 2016, 06:25 AM.
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Mesopredator
Member Avatar
Disaster taxa
[ *  *  *  *  *  * ]
Scheiss, you beat me to it with the last one. Was going to keep a low profile and work on my secret project, and suddenly blitz-post thousands of scientific stuff I collected and crash the carnivoran economy. Oh well.

Remember that time we talked about intelligence? I made some stupid mistakes but anyway I had the hypothesis that omnivores are more intelligent. This sort of confirms that (read on, not saying it is the only use of intelligence). The idea goes that they need more brainpower because they - usually - can't rely on a single food source. It pays of for them to be innovative as it opens the way for new food sources. Felines at least, only perform - more or less - one action when hunting for prey. Let me explain: they are less dependent on seasonal foods, how (such as digging) or when to obtain them, etc. Felines have a more stable diet than something like a beech marten or raccoon. Beech martens might need to switch from eggs, to rodents, to fruits, to nuts. That could require extra brain power. (Side note: I remember you showed me the Red Queen hypothesis at that topic which I was totally unaware of until then.)

There was a study that showed that rodents - among others - showed increased brain sizes but later decreased brain sizes in response to urban environments. Here the idea was similar, that behavioral plasticy is needed for the novel environment but that on a longer time base the energy-consuming large brain is no longer needed because the area becomes predictable. The same study showed however that insectivores had an increase in rural areas as well. What the reason for that is I do not know. [Can provide old study if necessary.]

Ok - back to this study, what I said can be considered speculation. And let me say that I fully agree, however, with the researcher that said in the press release that there's different ways that intelligence, brain capacity, or brain size is used. Which I see (I jumped right to comment, since I knew the study) you say too.

Also thanks Ursus for giving the table, I might have done something wrong but I couldn't get access to the full paper. As I take a better look at that, I wonder why the red panda has such a large brain size since I thought it relied mostly on bamboo. I suppose it is more omnivorous as I thought.

Another new hypothesis of mine (shamefully inspired by the book by Xiaoming Wang on dogs) is that those in northern regions have larger brain sizes compared to southern species (Herpestidae, Hyaenidae*, Viverridae score low) because in the south food is more plentiful and perhaps less seasonal. Those that can survive food shortages in winter might need to have better brains (behavioural plasticy). *I'm not sure if I can classify the hyenas as a southern species since at least spotted hyenas have lived in temperate areas (striped hyenas have lived in Europe, but don't know how far up north). Maybe hyenas have such low brains since two species (striped and brown) live mostly of carrion and another one of termites (aardwolf). Carrion and termites are stable foods that do not require behavioural plasticy - I claim.

As for canines, I think their brain sizes could support the social intelligence theory. Most canines, with exception of such species as raccoon dogs, still - mostly (!) - rely on a stable diet. Wolves in Yellowstone might take young and old in different seasons, but those young and old would likely both be elk.

Also we need to see individual species (species specific) relative brain size instead of average relative brain size of a family: if I understood the table correctly. [I'm writing this fast, and read it fast, so be aware of errors. Did not read text bellow table, am lazy.]
Edited by Mesopredator, Jan 30 2016, 07:22 AM.
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Ursus arctos
Autotrophic Organism

zergthe,
There was a grizzly that learned to disarm traps by setting them off using sticks and stones. But, because he was male, that skill died with him. I wonder if a female would have taught her cubs.
That gorillas can communicate with one another, and have a real understanding -- it sounded like Vubu was warning the unsuspecting human of the dangerous trap -- is darned cool & impressive.

Mesopredator
Jan 30 2016, 07:21 AM
Scheiss, you beat me to it with the last one. Was going to keep a low profile and work on my secret project, and suddenly blitz-post thousands of scientific stuff I collected and crash the carnivoran economy. Oh well.


Just one article should hardly put a dent in your plans!

Mesopredator
Jan 30 2016, 07:21 AM
Remember that time we talked about intelligence? I made some stupid mistakes


I've made too many stupid mistakes to count, let alone remember them all. Let alone to remember mistakes other people made.

Mesopredator
Jan 30 2016, 07:21 AM
but anyway I had the hypothesis that omnivores are more intelligent. This sort of confirms that (read on, not saying it is the only use of intelligence). The idea goes that they need more brainpower because they - usually - can't rely on a single food source. It pays of for them to be innovative as it opens the way for new food sources. Felines at least, only perform - more or less - one action when hunting for prey. Let me explain: they are less dependent on seasonal foods, how (such as digging) or when to obtain them, etc. Felines have a more stable diet than something like a beech marten or raccoon. Beech martens might need to switch from eggs, to rodents, to fruits, to nuts. That could require extra brain power. (Side note: I remember you showed me the Red Queen hypothesis at that topic which I was totally unaware of until then.)

There was a study that showed that rodents - among others - showed increased brain sizes but later decreased brain sizes in response to urban environments. Here the idea was similar, that behavioral plasticy is needed for the novel environment but that on a longer time base the energy-consuming large brain is no longer needed because the area becomes predictable. The same study showed however that insectivores had an increase in rural areas as well. What the reason for that is I do not know. [Can provide old study if necessary.]


I'm sure dietary flexibility would increase brain size.
Research on mammals found that relative brain size was the best predictor (they used) to predict success of an introduced species -- even better than similarity of the new environment to that species native environment!
Probably because larger brains give greater overall flexibility, helping those animals better adapt to the new environment (which is going to be different, even if climates are similar).

So this fits that pattern as well.

A problem, though, is that there are so many factors, it is hard to accurately see anything accurately. So many factors makes lots of noise so we can see a million patterns when none exist, overestimate others, and even see some effects in the opposite direction of how they work in reality.
This makes it dangerous to draw any sort of strong conclusions from just looking.
Especially when we're rationalizing after the fact.

My favorite analogy is to try weighing a feather using a bathroom scale. While that feather rests loosely in the pouch of a kangaroo vigorously jumping up and down.
That feather has real weight that could be weighed, but the scale isn't very sensitive, and there is so much else going on that will mess with the readings that it's hard to draw any sort of conclusions.

That's what I'm worried about here.
And you can see there are huge numbers of variables with these animals. Social behavior of the species, being omnivorous, red queen arms races with prey, a bunch of details related to each of these (eg, like you mentioned: climate, and seasonal changes), etc...



Mesopredator
Jan 30 2016, 07:21 AM
Also thanks Ursus for giving the table, I might have done something wrong but I couldn't get access to the full paper.


It is over the 200 kb limit for attaching to posts.
I was able to download it from sci-hub (where it's free).

Mesopredator
Jan 30 2016, 07:21 AM
As I take a better look at that, I wonder why the red panda has such a large brain size since I thought it relied mostly on bamboo. I suppose it is more omnivorous as I thought.


That last sentence is something I consider dangerous.
But, anyway, the red panda's brain size was still smaller than the average for canids and ursids (0.189 vs 0.193 and 0.196).

Mesopredator
Jan 30 2016, 07:21 AM
Another new hypothesis of mine (shamefully inspired by the book by Xiaoming Wang on dogs) is that those in northern regions have larger brain sizes compared to southern species (Herpestidae, Hyaenidae*, Viverridae score low) because in the south food is more plentiful and perhaps less seasonal. Those that can survive food shortages in winter might need to have better brains (behavioural plasticy). *I'm not sure if I can classify the hyenas as a southern species since at least spotted hyenas have lived in temperate areas (striped hyenas have lived in Europe, but don't know how far up north). Maybe hyenas have such low brains since two species (striped and brown) live mostly of carrion and another one of termites (aardwolf). Carrion and termites are stable foods that do not require behavioural plasticy - I claim.


This does have intuitive appeal, but I'd also like to point out that the sun bear has by far the largest brain relative to size among Carnivorans, and it lives along the equator. Although, Ben Kilham's model of bear behavior would support your idea: bears have evolved to exploit concentrated/dense, but seasonal, resources.
The African wild dog (according to the data below) is the next-biggest brained, but it isn't an omnivore so I'd imagine an entirely different pattern of evolutionary pressures impact them, as you say:

Mesopredator
Jan 30 2016, 07:21 AM
As for canines, I think their brain sizes could support the social intelligence theory. Most canines, with exception of such species as raccoon dogs, still - mostly (!) - rely on a stable diet. Wolves in Yellowstone might take young and old in different seasons, but those young and old would likely both be elk.


Finally:
Mesopredator
Jan 30 2016, 07:21 AM
Also we need to see individual species (species specific) relative brain size instead of average relative brain size of a family: if I understood the table correctly. [I'm writing this fast, and read it fast, so be aware of errors. Did not read text bellow table, am lazy.]


I was able to reproduce the values in R (even though they messed up their explanation of how they got the numbers :-/ ):
$`Acinonyx jubatus`
[1] -0.2413893

$`Ailurus fulgens`
[1] 0.1898132

$`Arctictis binturong`
[1] -0.2423062

$`Bassariscus astutus`
[1] 0.1835838

$`Canis lupus`
[1] 0.199938

$`Caracal caracal`
[1] -0.1458229

$`Chrysocyon brachyurus`
[1] 0.3104456

$`Crocuta crocuta`
[1] -0.1237568

$`Felis manul`
[1] 0.2273262

$`Gulo gulo`
[1] 0.07305499

$`Helarctos malayanus`
[1] 0.9376162

$`Helogale parvula`
[1] -0.238702

$`Hemigalus derbyanus`
[1] -0.0636192

$`Hyaena hyaena`
[1] -0.2597109

$`Leopardus pardalis`
[1] 0.08309683

$`Leptailurus serval`
[1] -0.0324602

$`Lontra canadensis`
[1] 0.1408677

$`Lycaon pictus`
[1] 0.4129228

$`Lynx rufus`
[1] 0.1720805

$`Mungos mungo`
[1] -0.5955586

$`Mustela putorius`
[1] -0.3731901

$`Nasua narica`
[1] 0.0251782

$`Otocyon megalotis`
[1] -0.1278348

$`Panthera leo`
[1] -0.2638475

$`Panthera onca`
[1] -0.3584881

$`Panthera pardus`
[1] -0.1460187

$`Panthera tigris`
[1] -0.04787916

$`Potos flavus`
[1] 0.022077

$`Prionailurus viverrinus`
[1] -0.06414412

$`Puma concolor`
[1] -0.1407867

$`Speothos venaticus`
[1] 0.05517976

$`Taxidea taxus`
[1] 0.1405014

$`Tremarctos ornatus`
[1] -0.1628254

$`Uncia uncia`
[1] -0.2550162

$`Ursus americanus`
[1] 0.1818177

$`Ursus arctos`
[1] 0.1087053

$`Ursus maritimus`
[1] -0.08511177

$`Vulpes lagopus`
[1] 0.253689

$`Vulpes zerda`
[1] 0.2505748
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Snow Leopard
Member Avatar
Herbivore
[ *  *  *  * ]
Ursus arctos
Jan 30 2016, 05:44 AM
I saw two articles I thought were really cool in the last couple days, so figured I'd post them both here.

Young gorillas dismantling traps:
Bush-meat hunters set thousands of rope-and-branch snares in Rwanda's Volcanoes National Park, where the mountain gorillas live. The traps are intended for antelope and other species but sometimes capture the apes.
...


Poachers build the snares by tying a noose to a branch or a bamboo stalk, Vecellio explained.

Using the rope, they pull the branch downward, bending it. They then use a bent stick or rock to hold the noose to the ground, keeping the branch tense. A sprinkling of vegetation camouflages the noose.

When an animal budges the stick or rock, the branch springs upward, closing the noose around the prey. If the creature is light enough, it will actually be hoisted into the air.
...


On Tuesday tracker John Ndayambaje spotted a trap very close to the Kuryama gorilla clan. He moved in to deactivate the snare, but a silverback named Vubu grunted, cautioning Ndayambaje to stay away, Vecellio said.

Suddenly two juveniles—Rwema, a male; and Dukore, a female; both about four years old—ran toward the trap.

As Ndayambaje and a few tourists watched, Rwema jumped on the bent tree branch and broke it, while Dukore freed the noose.

The pair then spied another snare nearby—one the tracker himself had missed—and raced for it. Joined by a third gorilla, a teenager named Tetero, Rwema and Dukore destroyed that trap as well.


Really cool stuff!





The other:
Brain size predicts problem-solving ability in mammalian carnivores.
I attached a csv of their data, but found it extremely hard to interpret on my own:
The data is very "noisy", a huge amount of things going on you may want to (and hypothetically could) consider.

An example of what I mean:
The animals were given a puzzle box with food in it. The trick was figuring out how to open it.
A jaguar named Tizon worked on the box for 22 minutes on his first try before opening it and eating his reward. His next three tries took him about 3 minutes, 2 minutes, and then only half a minute.
That makes sense. Tizon figured out the trick.

The tiger Sevaki spent just over 4 minutes on his first try. However, after succeeding, he didn't eat his reward.
His second try took a little under 6 minutes. Again, he succeeded, but didn't eat his reward.
He failed on all three of his later attempts. Did he actually care about the food?

The black bear Jam spent a little under 15 minutes on her first try. She succeeded, but didn't eat. She failed her remaining two attempts.

Another tiger and three snow leopards also showed that sort of behavior.

But a lot of other animals did succeed on their first try, eat the reward, and then fail on later ones. How can we interpret that?
I would hesitate to attribute that to being less good at problem solving.

I also wouldn't generalize to different sorts of tasks. The social carnivores that take large prey would all probably do extremely well on tasks of cooperation, for example.


However, for a variety reasons I don't wish to cover here, I think it is best to stick to the author's analysis.
Table comparing results by families:
FamilyNo. of SpeciesRelative brain sizeTotal no. of trialsNo. of individuals testedNo. of individuals successfulIndividuals successful (%)
Ailuridae10.189184125
Canidae70.193 (-0.13 to 0.41)7525624
Felidae13-0.093 (-0.36 to 0.23)179521528.8
Herpestidae2-0.417 (-0.59 to -0.24)14500
Hyaenidae2-0.192 (-0.26 to -0.12)237228.6
Mustelidae4-0.005 (-0.37 to 0.14)8117847.1
Procyonidae30.077 (0.02 to 0.18)4213753.8
Ursidae50.196 (-0.16 to 0.94)4513969.2
Viverridae2-0.153 (-0.24 to -0.06)174125
Sum or mean394951404935


The discussion section:

The connection between brain size and cognitive abilities has been
called into question by both a study pointing out the impressive
cognitive abilities of small-brained species, such as bees and ants (7),
and another study doubting that overall brain size is a valid proxy for
cognitive ability (9). In the former case, Chittka and Niven (7) argue
that larger brains are partially a consequence of the physical need
for larger neurons in larger animals and partially caused by in-
creased replication of neuronal circuits, which confers many ad-
vantages for larger-brained species, such as enhanced perceptual
abilities and increased memory storage. Chittka and Niven (7)
conclude that neither of these properties of larger brains necessarily
enhance cognitive abilities. Interestingly, our results actually show
that carnivore species with a larger average body mass performed
worse than smaller-bodied species on the task that we presented to
them. Thus, it truly does seem that a larger brain size relative to
body size is an important determinant of performance on this task,
and it is not the case that larger animals are more successful simply
because their brains are larger than those of smaller species.
Regarding whether overall brain size is a valid proxy for cognitive
abilities, the use of whole-brain size as a predictor of cognitive
complexity in comparative studies is questioned, because the brain
has different functional areas, some of which are devoted to partic-
ular activities, such as motor control or sensory processing. Given this
high degree of modularity in the brain, Healy and Rowe (8, 9) argue
that overall brain size is unlikely to be a useful measure when ex-
amining how evolution has shaped the brains of different species
to perform complex behaviors. Although the brain has functional
modules, such as the hippocampus or the olfactory bulbs, which may
be under specific selection pressures (31), these modules may also
exhibit coordinated changes in size because of constraints on ways in
which the brain can develop (32). In addition to functionally spe-
cialized modules, the brain also contains broad areas, such as the
mammalian neocortex, that control multiple processes. Thus, there
are reasons to believe that overall brain size may be an informative
proxy for cognitive abilities, despite the modular nature of the brain.
Here we examined relationships between relative brain size, size of
specific brain regions, and problem-solving success. Although none of
the regional brain volumes that we examined significantly predicted
success on this task (Table S9), the addition of the volume of these
brain regions improved the ability of our models to explain perfor-
mance in the puzzle box task over a model containing only total brain
volume (Table 3). We emphasize, however, that only 17 species were
included in that analysis. Nevertheless, relative brain size was a sig-
nificant predictor of problem-solving success across species, and this
result was robust in all of our analyses. Thus, our data provide im-
portant support for the idea that relative brain size can be useful in
examining evolutionary relationships between neuroanatomical and
cognitive traits and corroborate results from artificial selection ex-
periments showing that larger brain size is associated with enhanced
problem solving (5). It will be important in future work to use more
detailed noninvasive brain imaging methods rather than endocasts to
evaluate whether hypothetically important brain areas, such as pre-
frontal and cingulate cortexes, contribute to the relationship between
brain size and performance during problem solving.
Assessment of the ecological and neuroanatomical predictors of
problem-solving ability has some important implications for hy-
potheses proposed to explain the adaptive value of large brains and
sophisticated cognition. One such hypothesis that has garnered
much support in primate studies is “the social brain hypothesis” (33,
34), which proposes that larger brains evolved to deal with chal-
lenges in the social domain. This hypothesis posits that selection
favored those individuals best able to anticipate, respond to, and
perhaps even manipulate the actions of conspecific group members.
However, a major shortcoming of the social brain hypothesis (35,
36) is its apparent inability to explain the common observation that
species with high sociocognitive abilities also excel in general in-
telligence (37, 38). There is, in fact, a long-standing debate as to
whether animal behavior is mediated by cognitive specializations
that have evolved to fulfill specific ecological functions or instead,
domain-general mechanisms (38, 39). If selection for social agility
has led to the evolution of domain-general cognitive abilities, then
species living in social groups should solve technical problems better
than solitary species. However, we found that carnivore species
living in social groups performed no better on our novel technical
problem than solitary species. Thus, whereas social complexity may
select for enhanced ability to solve problems in the social domain
(40), at least in carnivores, greater social complexity is not associated
with enhanced ability to solve a novel technical problem.
Our results are similar to those obtained in the work by MacLean
et al. (12), which examined relationships among brain size, social
complexity, and self-control in 23 species of primates. In both that
study and our own study, species with the largest brains showed the
best performance in problem-solving tasks. However, in neither pri-
mates nor carnivores did social complexity predict problem-solving
success. This finding is also consistent with results obtained in the
work by Gittleman (41), with analysis of 153 carnivore species that
revealed no difference in brain size relative to body size between
social and solitary species. Nevertheless, in this study, we were only
able to present carnivores with a single problem-solving task, and we
were only able to test one to nine individuals per species. Ideally,
future studies will present a large array of carnivores with additional
cognitive challenges and will test more individuals per species.
A second hypothesis forwarded to explain the evolution of larger
and more complex brains, the cognitive buffer hypothesis (42, 43),
posits that large brains evolved to allow animals to cope with
socioecological challenges and thus, reduce mortality in changing
environments. Previous work has shown convincingly that diet is a
significant predictor of brain size in carnivores (27), as it is in pri-
mates (12), and this study shows that carnivore species with larger
brains are more likely to solve a novel technical problem. However,
an explicit test of the cognitive buffer hypothesis has not yet been
attempted with mammalian carnivores.
Overall, our finding that enhanced problem solving is related to
disproportionally large brain size for a given body mass is important
for several reasons. First, although there is correlational evidence for
an association between absolute or relative brain size and problem-
solving abilities, experimental evidence is extremely rare. The lack of
experimental evidence has led to criticisms of the use of brain size as
a proxy for problem-solving abilities (8, 9, 44). We offer experimental
evidence that brain size is, indeed, a useful predictor of performance,
at least in the single problem-solving task that we posed to our
carnivore subjects. Although only brain size relative to body mass was
a significant predictor of success with our puzzle box, species with
larger absolute brain volumes also tended to be better than others at
opening the puzzle box (Figs. 2 and 3 and Table S2). Second, the vast
majority of work on this topic has focused on primates, fish, and birds
(5, 10, 11, 13–16). Our results offer new evidence for the relationship
between brain size and problem-solving abilities in mammalian car-
nivores. The previous lack of support for this relationship across a
diverse set of taxa has limited both its validity and its generality.
Thus, the findings presented here represent an important step for-
ward in our understanding of why some animals have evolved large
brains for their body size.
For a second it looked like the 'O' in Rope, was an A... lol
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zergthe
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@Ursus arctos
Impressive, no doubt about it. But I am inclined to believe, had that male been a female with cubs, that the skill would've been passed down and would have been extremely valuable. To bad Smokey didn't go to the bear community and teach them how to disarm traps... lol
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Can some birds be just as smart as apes?
Researchers figure out similarities in brain architecture


Date: March 3, 2016
Source: Ruhr-Universitaet-Bochum

At first glance, the brains of birds and mammals show many significant differences. In spite of that, the cognitive skills of some groups of birds match those of apes.

Research results gathered in the recent decades have suggested that birds have sophisticated cognitive skills. According to one theory, they are able to apply those only in specific situations, for example when hoarding food. In a review article in the journal Trends in Cognitive Sciences, Prof Dr Onur Güntürkün from the Ruhr-Universität Bochum and Prof Dr Thomas Bugnyar at the University of Vienna demonstrate that this is not the case.

Together, both researchers compiled studies which had revealed diverse cognitive skills in birds. "The mental abilities of corvids and parrots are as sophisticated and diverse as those of apes," says Onur Güntürkün, Head of the Department for Biopsychology in Bochum. Among other things, they are capable of thinking logically, of recognising themselves in the mirror and of empathy.

Complex cognition without cortex

In mammals, cognitive skills are controlled by the multi-layered cerebral cortex, also called neocortex. This brain structure does not exist in birds; instead, complex mental tasks are managed by the so-called pallium. Moreover, birds have much smaller brains than apes. "How, then, are birds capable of the same cognitive performance as apes?" asks Güntürkün. "Is it possible that very different brain mechanisms for complex cognitive processes have developed independently in birds and in mammals in the 300 million years of their existence?"

To address this question, he and his colleague analysed numerous neuro-anatomic studies. Their conclusion: on the whole, the brains of both animal groups have indeed very different structures. When examining them in detail, however, similarities have become apparent. Single modules of the brains, for example, are wired in a similar way, and both animal groups have a prefrontal brain structure that controls similar executive functions.

Origin of similarities is unknown

It is not known how these similarities have evolved. Either their last common ancestor passed the neuronal basis to birds and mammals. Or -- and the authors consider this more likely -- they evolved independently of each other, because both animal groups faced the same challenges. According to the researchers, this would mean that certain wiring patterns in the brain are necessary to boost cognitive performance.

"What is clear is that the multi-layered mammalian cortex is not required for complex cognition," concludes Güntürkün. "The absolute brain weight is not relevant for mental abilities, either." While ape brains weigh 275 to 500 gram on average, birds, who are just as skilful despite lacking a cortex, only manage 5 to 20 gram.

Story Source:
Ruhr-Universitaet-Bochum. "Can some birds be just as smart as apes? Researchers figure out similarities in brain architecture." ScienceDaily. www.sciencedaily.com/releases/2016/03/160303084615.htm (accessed March 4, 2016).




Journal Reference:
Onur Güntürkün, Thomas Bugnyar. Cognition without Cortex. Trends in Cognitive Sciences, 2016; DOI: 10.1016/j.tics.2016.02.001

Summary
Assumptions on the neural basis of cognition usually focus on cortical mechanisms. Birds have no cortex, but recent studies in parrots and corvids show that their cognitive skills are on par with primates. These cognitive findings are accompanied by neurobiological discoveries that reveal avian and mammalian forebrains are homologous, and show similarities in connectivity and function down to the cellular level. But because birds have a large pallium, but no cortex, a specific cortical architecture cannot be a requirement for advanced cognitive skills. During the long parallel evolution of mammals and birds, several neural mechanisms for cognition and complex behaviors may have converged despite an overall forebrain organization that is otherwise vastly different.

Trends
Cognition in corvids and parrots reaches the same level of excellence and diversity as in apes. Among others, bird cognition encompasses abilities such as delay of gratification, mental time travel, reasoning, metacognition, mirror self-recognition, theory of mind, and third-party intervention.

The cerebrum of birds and mammals is homologous but very differently organized.

Birds lack a neocortex but have instead several large pallial aggregations without apparent laminar structure. However, according to some scientists, these aggregations might correspond to cortical layers.

Independent from each other, birds and mammals have developed similar brain organizations that could constitute the neural basis of their cognitive skills. Birds have a functional analog to the prefrontal cortex that generates executive functions. Their telencephalic connectome is highly similar to that of diverse mammalian species and they show a ‘hidden’ lamination that resembles cortical canonical circuits in parts of their sensory pallial territories.


http://www.cell.com/trends/cognitive-sciences/abstract/S1364-6613(16)00042-5
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Mesopredator
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Yeah Ursus I recently discovered sci-hub and checked myself (before your response). From the species I've seen I do not think that we can make any generalizations at all.

It seems almost random actually.

Was surprised that leopard failed while lion succeeded, and painted dog succeeded while wolf failed.
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Despite their small brains, ravens and crows may be just as clever as chimps, research suggests
Study shows how these birds parallel great apes in motor self-regulation


Date: April 26, 2016
Source: Lund University
Summary:
A new study suggests that ravens can be 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.
FULL STORY

Posted Image
Credit: Helena Osvath

A study led by researchers at Lund University in Sweden suggests that ravens can be 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 brain size 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 inhibitory control.

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.

"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 brain, but this study clearly shows that bird brains are not simply birdbrains after all!"

Story Source: Lund University. "Despite their small brains, ravens and crows may be just as clever as chimps, research suggests: Study shows how these birds parallel great apes in motor self-regulation." ScienceDaily. www.sciencedaily.com/releases/2016/04/160426101527.htm (accessed April 27, 2016).




Journal Reference:
Can Kabadayi, Lucy A. Taylor, Auguste M. P. von Bayern, Mathias Osvath. Ravens, New Caledonian crows and jackdaws parallel great apes in motor self-regulation despite smaller brains. Royal Society Open Science, 2016; 3 (4): 160104 DOI: 10.1098/rsos.160104

Abstract
Overriding motor impulses instigated by salient perceptual stimuli represent a fundamental inhibitory skill. Such motor self-regulation facilitates more rational behaviour, as it brings economy into the bodily interaction with the physical and social world. It also underlies certain complex cognitive processes including decision making. Recently, MacLean et al. (MacLean et al. 2014 Proc. Natl Acad. Sci. USA 111, 2140–2148. (doi:10.1073/pnas.1323533111)) conducted a large-scale study involving 36 species, comparing motor self-regulation across taxa. They concluded that absolute brain size predicts level of performance. The great apes were most successful. Only a few of the species tested were birds. Given birds' small brain size—in absolute terms—yet flexible behaviour, their motor self-regulation calls for closer study. Corvids exhibit some of the largest relative avian brain sizes—although small in absolute measure—as well as the most flexible cognition in the animal kingdom. We therefore tested ravens, New Caledonian crows and jackdaws in the so-called cylinder task. We found performance indistinguishable from that of great apes despite the much smaller brains. We found both absolute and relative brain volume to be a reliable predictor of performance within Aves. The complex cognition of corvids is often likened to that of great apes; our results show further that they share similar fundamental cognitive mechanisms.

http://rsos.royalsocietypublishing.org/content/3/4/160104
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Asadas
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Good social skills make animals smarter
https://youtu.be/8nXGxL9f_BI
By Virginia MorellApr. 1, 2016 , 9:00 AM

Using tools doesn’t make humans, dolphins, and crows smart. Rather, it’s the stress and challenge of living with others—recognizing friend from foe, calculating who to deceive and who to befriend—that led these and other social creatures to evolve their cognitive skills. That’s the gist of the social intelligence hypothesis, an idea that’s been around since 1966. But does having to remember whose lice need picking actually improve other mental abilities, like figuring out how to open a locked box with a hunk of meat inside? A new study of four carnivores—two social and two solitary species—suggests that it does.

“They’ve taken an important issue and tested it in a simple but novel way,” says Richard Byrne, an evolutionary psychologist at The University of St. Andrews in the United Kingdom, who was not involved in the study. “The results are clear: The cognitive benefit from being a social carnivore does transfer” to a mental ability that has nothing to do with being social, he says.

Other researchers think the results aren’t as clear-cut. “It is important and a valuable stepping stone in our quest to understand how intelligence evolved, but like all studies, it is one piece of a larger puzzle,” says Sarah Benson-Amram, a zoologist at the University of Wyoming in Laramie, whose recent comparative study of 39 species of carnivores reached the opposite conclusion.

Scientists devised the social intelligence hypothesis to explain the evolution of the human brain. They’ve found that most social species (from chimpanzees to social wasps) have relatively large brains and are cognitively sophisticated, adept at experiments designed to test their smarts. But some researchers argue that another factor—a challenging environment—may also stimulate cognitive evolution. If so, then more solitary species could also be large-brained and smart thanks to the ecological difficulties they face.

“I thought that carnivores offered a good way to test these two hypotheses,” says Natalia Borrego, who was a behavioral ecologist at the University of Miami in Florida at the time the study was conducted and the study’s lead author. She notes that the species she and her University of Miami colleague, Michael Gaines, selected to study are related, but socially distinct. All are in the family Carnivora. The spotted hyenas (Crocuta crocuta) have hierarchical societies similar to those of primates; lions (Panthera leo) live in egalitarian prides with as many as 21 members; whereas tigers (P. tigris) and leopards (P. pardus) lead more solitary lives, except when females have young or when males and females meet to mate. The four species also pursue widely distributed prey in similar patchy and challenging habitats, and they need flexible hunting strategies. Yet lions and hyenas typically cooperate with their own kind to bring home the bacon, whereas leopards and tigers hunt alone.

To find out which, if any, of these carnivores were better at solving a problem they’d never previously encountered, Borrego devised a large, rectangular box of marine-grade polymer that could be opened only by pulling a rope away from the box at a 180° angle. The rope was attached to a spring latch. She baited the box with raw meat, and she drilled holes in the box’s sides so that the prize could be seen and smelled.

Between May 2012 and May 2015, Borrego placed the box inside the outdoor enclosures of the four species at wildlife sanctuaries, parks, and zoos in Florida and South Africa. Each animal, other than the hyenas, encountered the box alone and for three 10-minute trials. Because of constraints at the hyena facilities, one to four animals were tested at a time. To ensure the carnivores were motivated, none were fed for 24 hours before the experiment. They could use either their mouths or paws to open the box. “I wasn’t sure if they would even approach it,” Borrego says, because many animals regard novel items as dangerous.

She tested 48 individuals and found that the social animals—hyenas and lions—were the most successful. Eight out of nine hyenas, and 16 of the 21 lions correctly pulled the rope (as in the photo) and seized the meat; whereas only six of the 11 leopards and two of the seven tigers did so (see video, above). Lions were also the most exploratory species, circling, digging, biting, pawing, and pushing the box, the team will report next month in Animal Behaviour.

“This isn’t a task that requires social cognition,” Borrego says. “Yet, the social species were better at it, and that suggests there’s something about being social that bolsters cognition overall.”

Other researchers concur, but with caveats. “They did find a nice link between sociality and success” on this task, says Evan MacLean, a comparative psychologist at Duke University in Durham, North Carolina. But he wonders what type of cognition the ability to open a puzzle box actually demonstrates. “It may be reflective of trial and error learning, insight, or just of curiosity or interest in novel objects.”

The puzzle box is also not particularly “ecologically relevant,” to the carnivores, notes primatologist Frans de Waal at Emory University in Atlanta, who would like to see the animals tested on some type of predator-prey task. Still, it is “a good first step and a fresh approach to the intelligence of carnivores, a group we have neglected for too long.”

http://www.sciencemag.org/news/2016/04/good-social-skills-make-animals-smarter

Dr. Yamaguchi argued that there is no evidence with intelligence and sociability. I am inclined to believe that social animals have higher intelligence as Dr. Packer stated social animals learn role play are keen to advantage and disadvantages.

Given the different results, I think animal intelligence it is difficult to gauge though measurements would disagree.
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Ophiophagy
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I think corids are wayy up there specially like tapian posted ravens i have worked with lots of corvids and they are smarter than the smartest parrots even greys when it comes to training certain things and just being smart in some ways they just have it

parrots are smart in another way language ability tricks etc.. but wow corvids just shock you how smart they are by learning how to open the avairy door whenever they want then they go back in and one actually tried to close his door lool they figure out the most insane things that parrots dont unlock doors mimic cats they will go behind a group of birds and then SCREAM like a red tail or meow like a cat and make them scatter lol so many things my corvids did that would shock me

I would like next to have a pied crow but i have a hornbill, kook, and toucan that used in demos for education i sold most too caza approved zoos that dont use cages and have huge massive 5 thousand sq foot avaries which is where i like to see birds

my avairy is 30 by 20 feet not bad but not enough for a pied crow and 3 of what i have a fight would break out
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Something I was wondering was, is it known whether animals with a language have invented insults? I mean dolphins for example are very vocal animals so they have invented a complex language. But would this include insults?
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Bird brain? Ounce for ounce birds have significantly more neurons in their brains than mammals or primates

Date: June 13, 2016
Source: Vanderbilt University
Summary:
The first study to systematically measure the number of neurons in the brains of birds has found that they have significantly more neurons packed into their small brains than are stuffed into mammalian and even primate brains of the same mass.

Posted Image
The collection of avian brains that the scientists analyzed. For each species, the total number of neurons (in millions) in their brains is shown in yellow, the number of neurons (in millions) in their forebrains (pallium) is shown in blue and their brain mass (in grams) is shown in red. The scale bar in the lower right is 10 mm.
Credit: Suzana Herculano-Houzel, Vanderbilt University

The macaw has a brain the size of an unshelled walnut, while the macaque monkey has a brain about the size of a lemon. Nevertheless, the macaw has more neurons in its forebrain -- the portion of the brain associated with intelligent behavior -- than the macaque.

That is one of the surprising results of the first study to systematically measure the number of neurons in the brains of more than two dozen species of birds ranging in size from the tiny zebra finch to the six-foot-tall emu, which found that they consistently have more neurons packed into their small brains than are stuffed into mammalian or even primate brains of the same mass.

The study results were published online in a paper titled "Birds have primate-like numbers of neurons in the forebrain" in the Proceedings of the National Academy of Sciences early edition on the week of June 13.

"For a long time having a 'bird brain' was considered to be a bad thing: Now it turns out that it should be a compliment," said Vanderbilt University neuroscientist Suzana Herculano-Houzel, senior author of the paper with Pavel N?mec at the Charles University in Prague.

The study provides a straightforward answer to a puzzle that comparative neuroanatomists have been wrestling with for more than a decade: how can birds with their small brains perform complicated cognitive behaviors?

The conundrum was created by a series of studies beginning in the previous decade that directly compared the cognitive abilities of parrots and crows with those of primates. The studies found that the birds could manufacture and use tools, use insight to solve problems, make inferences about cause-effect relationships, recognize themselves in a mirror and plan for future needs, among other cognitive skills previously considered the exclusive domain of primates.

Scientists were left with a generally unsatisfactory fallback position: Avian brains must simply be wired in a completely different fashion from primate brains. Two years ago, even this hypothesis was knocked down by a detailed study of pigeon brains, which concluded that they are, in fact, organized along quite similar lines to those of primates.

The new study provides a more plausible explanation: Birds can perform these complex behaviors because birds' forebrains contain a lot more neurons than any one had previously thought -- as many as in mid-sized primates.

"We found that birds, especially songbirds and parrots, have surprisingly large numbers of neurons in their pallium: the part of the brain that corresponds to the cerebral cortex, which supports higher cognition functions such as planning for the future or finding patterns. That explains why they exhibit levels of cognition at least as complex as primates," said Herculano-Houzel, who recently joined the Vanderbilt psychology department.

That is possible because the neurons in avian brains are much smaller and more densely packed than those in mammalian brains, the study found. Parrot and songbird brains, for example, contain about twice as many neurons as primate brains of the same mass and two to four times as many neurons as equivalent rodent brains.

Not only are neurons packed into the brains of parrots and crows at a much higher density than in primate brains, but the proportion of neurons in the forebrain is also significantly higher, the study found.

"In designing brains, nature has two parameters it can play with: the size and number of neurons and the distribution of neurons across different brain centers," said Herculano-Houzel, "and in birds we find that nature has used both of them."

Although she acknowledges that the relationship between intelligence and neuron count has not yet been firmly established, Herculano-Houzel and her colleagues argue that avian brains with the same or greater forebrain neuron counts than primates with much larger brains can potentially provide the birds with much higher "cognitive power" per pound than mammals.

One of the important implications of the study, the neuroscientist said, is that it demonstrates that there is more than one way to build larger brains. Previously, neuroanatomists thought that as brains grew larger neurons had to grow bigger as well because they had to connect over longer distances. "But bird brains show that there are other ways to add neurons: keep most neurons small and locally connected and only allow a small percentage to grow large enough to make the longer connections. This keeps the average size of the neurons down," she explained.

"Something I love about science is that when you answer one question, it raises a number of new questions," said Herculano-Houzel.

Among the questions that this study raises are whether the surprisingly large number of neurons in bird brains comes at a correspondingly large energetic cost, and whether the small neurons in bird brains are a response to selection for small body size due to flight, or possibly the ancestral way of adding neurons to the brain -- from which mammals, not birds, may have diverged.

Herculano-Houzel hopes that the results of the study and the questions it raises will stimulate other neuroscientists to begin exploring the mysteries of the avian brain, especially how their behavior compares to that of mammals of similar numbers of neurons or brain size.

Story Source: Vanderbilt University. "Bird brain? Ounce for ounce birds have significantly more neurons in their brains than mammals or primates." ScienceDaily. www.sciencedaily.com/releases/2016/06/160613153411.htm (accessed June 14, 2016).




Journal Reference:
Seweryn Olkowicz, Martin Kocourek, Radek K. Lučan, Michal Porteš, W. Tecumseh Fitch, Suzana Herculano-Houzel, and Pavel Němec. Birds have primate-like numbers of neurons in the forebrain. PNAS, June 13, 2016 DOI: 10.1073/pnas.1517131113

Abstract
Some birds achieve primate-like levels of cognition, even though their brains tend to be much smaller in absolute size. This poses a fundamental problem in comparative and computational neuroscience, because small brains are expected to have a lower information-processing capacity. Using the isotropic fractionator to determine numbers of neurons in specific brain regions, here we show that the brains of parrots and songbirds contain on average twice as many neurons as primate brains of the same mass, indicating that avian brains have higher neuron packing densities than mammalian brains. Additionally, corvids and parrots have much higher proportions of brain neurons located in the pallial telencephalon compared with primates or other mammals and birds. Thus, large-brained parrots and corvids have forebrain neuron counts equal to or greater than primates with much larger brains. We suggest that the large numbers of neurons concentrated in high densities in the telencephalon substantially contribute to the neural basis of avian intelligence.

http://www.pnas.org/content/early/2016/06/07/1517131113

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Raccoons Ace Cognition Test (But Sometimes They Cheat)

By Mindy Weisberger, Senior Writer | October 26, 2017 01:51pm ET

Posted Image
Raccoons used curiosity and innovation to solve problems, sometimes arriving at solutions that researchers didn't expect.
Credit: Lauren Stanton

In the classic Aesop tale "The Crow and the Pitcher," a thirsty corvid who can't quite reach the water at the bottom of a jug cleverly drops pebble after pebble into the vessel until the water rises enough for the bird to take a drink.

Researchers have used this "Aesop's fable" scenario in experiments that test cognition in birds and primates. The test helps researchers see if the animals could learn to recognize cause and effect and use that knowledge to solve a problem, as Aesop's crow did.

Recently, scientists turned to raccoons, learning that the wily creatures were not only capable of solving Aesop's problem, but also willing to bend the rules to get their rewards.

Although mammalian carnivores had never previously been tested with these methods, the researchers suspected that raccoons would be good candidates; prior studies had shown that raccoons are creative problem-solvers and are more intelligent than domestic cats, the study authors wrote. Raccoons are also known to have an affinity for water, and were therefore likely to already have an innate understanding of water displacement, study co-author Lauren Stanton, a doctoral candidate with the Program in Ecology at the University of Wyoming, told Live Science in an email.

The study authors trained eight raccoons using cylinders of water and stones of different sizes, with floating marshmallows as the reward. Nearly all of the raccoons were extremely curious and hands-on with the test materials — so much so that the scientists often had to search for missing stones that their subjects had buried in their litter boxes or hidden in the dens where the animals slept, Stanton said. While this behavior sidestepped the experiment, it also demonstrated the raccoons' curiosity, an important component of cognition, the researchers wrote in the study.

Two of the animals learned to drop stones into the liquid to retrieve a marshmallow treat, progressing to the next stage of trials, in which they had to choose among objects of different weights and buoyancies. This was done to see if the animals recognized a connection between weight and water displacement.

Posted Image
The "Aesop's Fable" experiment tasked raccoons with bringing a floating treat within reach by dropping objects into water.
Credit: Lauren Stanton

During the experiments, some of raccoons arrived at unique and unexpected solutions to earn their treats. One enterprising individual climbed atop the heavy tower that held the water, and rocked back and forth until the structure tipped over, the study authors reported. And the two raccoons that worked with buoyant objects figured out that they could repeatedly push down on floating balls to make waves that would splash marshmallow bits within reach.

"This demonstrated that raccoons are able to innovate solutions to novel problems, sometimes in ways we would not expect," Stanton told Live Science.

As only two raccoons completed the task in the manner it was intended, the researchers could form only limited conclusions about raccoon cognition and tool use, Stanton explained. But the findings did highlight the animals' innovation, "which is an important cognitive ability," she said.

"Our study is also a good reminder that when you give a test like Aesop's fable to a new species, you might find that they perform very differently than other animals and put their own spin on it," she added.

In addition, the results suggest Aesop's test could be used to gauge cognition in animals other than birds and primates, Stanton said.

The findings were published in the November issue of the journal Animal Cognition.

https://www.livescience.com/60784-raccoons-cheat-to-ace-cognition-test.html




Journal Reference:
Stanton, L., Davis, E., Johnson, S. et al. Adaptation of the Aesop’s Fable paradigm for use with raccoons (Procyon lotor): considerations for future application in non-avian and non-primate species Anim Cogn (2017) 20: 1147. https://doi.org/10.1007/s10071-017-1129-z

Abstract
To gain a better understanding of the evolution of animal cognition, it is necessary to test and compare the cognitive abilities of a broad array of taxa. Meaningful inter-species comparisons are best achieved by employing universal paradigms that standardize testing among species. Many cognitive paradigms, however, have been tested in only a few taxa, mostly birds and primates. One such example, known as the Aesop’s Fable paradigm, is designed to assess causal understanding in animals using water displacement. To evaluate the universal effectiveness of the Aesop’s Fable paradigm, we applied this paradigm to a previously untested taxon, the raccoon (Procyon lotor). We first trained captive raccoons to drop stones into a tube of water to retrieve a floating food reward. Next, we presented successful raccoons with objects that differed in the amount of water they displaced to determine whether raccoons could select the most functional option. Raccoons performed differently than corvids and human children did in previous studies of Aesop’s Fable, and we found raccoons to be innovative in many aspects of this task. We suggest that raccoon performance in this paradigm reflected differences in tangential factors, such as behavior, morphology, and testing procedures, rather than cognitive deficiencies. We also present insight into previously undocumented challenges that should better inform future Aesop’s Fable studies incorporating more diverse taxa.

https://link.springer.com/article/10.1007/s10071-017-1129-z
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https://en.m.wikipedia.org/wiki/Encephalization_quotient "Encephalization quotient (EQ) or encephalization level is a relative brain size measure that is defined as the ratio between actual brain mass and predicted brain mass for an animal of a given size, which may approximate intelligence level or cognition of the species.[9][10]

This is a more refined measurement than the raw brain-to-body mass ratio, as it takes into account allometric effects. The relationship, expressed as a formula, has been developed for mammals, and may not yield relevant results when applied outside this group.[11]

Additionally to volume, mass or cell count, the energy expenditure of the brain could be compared with that of the rest of the body... Mean EQ for mammals is around 1, with carnivorans, cetaceans and primates above 1, and insectivores and herbivores below. This reflects two major trends. One is that brain matter is extremely costly in terms of energy needed to sustain it.[21] Animals which live on relatively nutrient poor diets (plants, insects) have relatively little energy to spare for a large brain, while animals living from energy-rich food (meat, fish, fruit) can grow larger brains. The other factor is the brain power needed to catch food. Carnivores generally need to find and kill their prey, which presumably requires more cognitive power than browsing or grazing.[22][23] The brain size of a wolf is about 30% larger than a similarly sized domestic dog, again reflecting different needs in their respective way of life.[24]

It is worth noting, however, that of the animals demonstrating the highest EQ's (see associated table), many are primarily herbivorous, including apes, macaques, and proboscids. The dietary factor, therefore, may be less significant than certain others, like gregariousness.

Another factor affecting relative brain size is sociality and flock size.[25] For example, dogs (a social species) have a higher EQ than cats (a mostly solitary species). Animals with very large flock size and/or complex social systems consistently score high EQ, with dolphins and orcas having the highest EQ of all cetaceans,[4] and humans with their extremely large societies and complex social life topping the list by a good margin.[1]"

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