Information

What do the super-large brains of whales and elephants map to?

What do the super-large brains of whales and elephants map to?


We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

Elephants and whales have brains that are much larger than those of humans. It is presumed that much of their brain is used up for their larger bodies (after all, there is a allometric scaling between brain weight and body weight in mammals).

  • Do elephants and whales really need super-large somatosensory cortices to map to their larger bodies?
  • Have we mapped out the parts of the brains of a whale or elephant to see which parts of the brain are mapped to which parts of the body?

With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.

Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?

I asked the same question here, though I'm not convinced by any of the answers provided.


With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.

Ah, but they also have a complete three dimensions to move in, unlike us humans who only have about 2.5 dimensions to move in. Also, they have a number of different "limbs": tail, multiple fins, etc.

Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?

Why not? How do you accurately measure an intelligence that is structurally different from yours? You have to know how that intelligence works, and for that to happen you need to overcome the language barrier (which is still an issue with cetaceans, since many people think they're just dumb animals! Maybe some cetaceans are like primate apes. Maybe others are like primate humans!).


Here is a pdf overview of Cetacean brains. I hope this answers your question:

A few parts pulled from the article:

Cetaceans have very large brains, yes, but humans hold the top of the proportion scale: our brains are larger in comparison to our body size than most other species.

Cetacean brains are, for the most part, like other brains. That is, they are there for the processing of cognition (among other things). A large part of this processing power goes to echolocation.

Regarding similarities between primate and cetacean brains:

the expansion of the insular and cingulate cortices in cetaceans is consistent with high-level cognitive functions-such as attention, judgment, intuition, and social awareness-known to be associated with these regions in primates.

This view is further supported by the observation that the anterior insular and anterior cingulate cortex in cetacean species having the largest brains exhibit a large number of large layer V spindle neurons, similar to those originally reported to be unique to humans and great apes. These particular neurons are considered to be responsible for neural networks subserving aspects of social cognition.

Furthermore, though specifically regarding dolphins:

Laboratory studies of bottlenose dolphins have documented various dimensions of their intellectual abilities. These include an understanding of… (declarative knowledge); an understanding of… (procedural knowledge); an understanding of… (social knowledge); and an understanding of… (self knowledge). All these capabilities rest on a strong foundation of memory; investigations have demonstrated that bottlenose dolphin auditory, visual, and spatial memory are accurate and robust.

Lastly:

Field studies have documented impressive cultural learning of dialects, foraging sites, and foraging and feeding strategies in cetaceans.

So, to recap, the cetacean brain lends itself to, among inumerable other things, advanced auditory (sensory), personal (self), and interpersonal processing (social). Also, dolphins, and maybe other species as well, have advanced memory and language processing capabilities.


I think what is happening is a balance of evolutionary cost and resource cost.

Evolutionary cost is the amount of "effort" that natural selection spends refining a feature. Effort that could be spent refining other features, such as making it a more efficient swimmer, etc… so it is by no means free. If you can get the same capabilities with less generations of tweaking, it's all the better. Evolutionary costs are higher on animals that have longer generations and that there are fewer total animals.

Resource cost is how much energy a feature uses, as well as such costs as the high rate of childbirth deaths caused by big baby skulls squeezing through small pelvises.

Assume that everything else being equal, larger brains produce more cognitive capability. But on a large animal, there is far less selection pressure to get the maximum "I.Q points per pound of brain," since the relative resource cost of a large brain is much lower on large animals. So whale brains use largeness, rather than super-sophistication, to get the right level of cognitive capability.

Remember, whales ARE smart, because that intelligence comes cheaply due to the low cost of brain size on a large animal. They might be the equivalent to, say, an orangutan. But unlike the orangutan, they don't have the same pressure to keep the brain small, which would have much larger evolutionary costs.


You commented "Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?".

I would like add a few perspectives.

1) The notion that intelligence can be measured on a one dimensional scale is not really credible from any scientific perspective. See http://en.wikipedia.org/wiki/Theory_of_multiple_intelligences.

2) It seems human to feel that we are the intelligence ones and those who are most like us are the most intelligent. We are very casual in the way that we handle this and often don't notice that we are thinking this way.

What I am trying to get at is that we (collectively) are not very good about thinking about intelligence.

But the question you ask translates to me to be "What are Whales and Dolphins doing with their brains?". That is a huge question and it must surely depend in part on the species you pick.

For the Atlantic Spotted Dolphin species you should check out Denise Herzing who is spending her life trying to answer this question; See https://www.ted.com/talks/denise_herzing_could_we_speak_the_language_of_dolphins?language=en.

Dolphins, with a brain size similar to ours and Killer Whales with a larger brain seem to spend a lot of their time in tight social groups with a lot of social interaction.

But overal, it seems we are not yet intelligent enough to figure out what Dolphins are communicating about.


What if the filter is ahead of us?

These possibilities assume that the Great Filter is behind us—that humanity is a lucky species that overcame a hurdle almost all other life fails to pass. This might not be the case, however life might evolve to our level all the time but get wiped out by some unknowable catastrophe. Discovering nuclear power is a likely event for any advanced society, but it also has the potential to destroy such a society. Utilizing a planet's resources to build an advanced civilization also destroys the planet: the current process of climate change serves as an example. Or, it could be something entirely unknown, a major threat that we can't see and won't see until it's too late.

The bleak, counterintuitive suggestion of the Great Filter is that it would be a bad sign for humanity to find alien life, especially alien life with a degree of technological advancement similar to our own. If our galaxy is truly empty and dead, it becomes more likely that we've already passed through the Great Filter. The galaxy could be empty because all other life failed some challenge that humanity passed.

If we find another alien civilization, but not a cosmos teeming with a variety of alien civilizations, the implication is that the Great Filter lies ahead of us. The galaxy should be full of life, but it is not one other instance of life would suggest that the many other civilizations that should be there were wiped out by some catastrophe that we and our alien counterparts have yet to face.

Fortunately, we haven't found any life. Although it might be lonely, it means humanity's chances at long-term survival are a bit higher than otherwise.


Land Animals With The Best Memory

Again we need to look at animals with a long lifespan in order to find the terrestrial animals with the best memory.

Elephants

Elephants are really nice and loyal animals who take care of each other.

Scientists have found that elephants keep a map of all the water holes in their area. They always know where to go to get water for the little ones.

This shows a very good memory among adult elephants.

Most dog owners will let you know how good memories their dog has.

This is also why we can train dogs to learn a lot of tricks and to behave well.

Dogs wouldn’t be good service dogs and able to assist police officers if they weren’t able to remember a whole bunch of stuff. They can also recognize their owners after a very long time.

There are numerous examples of dogs who have found their way home after being away for a long time. This takes good memory skills and dogs are certainly among the most intelligent creatures in the animal kingdom.

Monkeys

Monkeys are very intelligent.

Apes and monkeys have very good memories. They are able to perform complicated tasks and they can remember what they learn.

They are probably this species we humans have done the most memory testing on.

They have been known to remember forms and signs and be able to sort puzzles and sort things. This shows us that apes and monkeys have at least some photographic memory. They can also be taught a long list of hand gestures and signs in order to communicate with humans.

The Rhesus monkeys have shown an amazing ability to be able to learn from past experiences. They will remember what happened last time that did the same thing.


How mammals evolved bigger brains

Scientists have pieced together a timeline of how brain and body size evolved in mammals over the last 150 million years by comparing the brain mass of 1400 living and extinct mammals.

For the 107 fossils examined, among them ancient whales and the oldest Old-World monkey skull ever found, they used endocranial volume data from skulls instead of brain mass data.

The brain measurements were then analysed along with body size to compare the scale of brain size to body size over deep evolutionary time.

The findings, published in Science Advances, showed that brain size relative to body size—long considered an indicator of animal intelligence—has not followed a stable scale over evolutionary time.

Famous “big-brained” humans, dolphins, and elephants, for example, attained their proportions in different ways. Elephants increased in body size, but surprisingly, even more in brain size. Dolphins, on the other hand, generally decreased their body size while increasing brain size. Great apes showed a wide variety of body sizes, with a general trend towards increases in brain and body size.

In comparison, ancestral hominins, which represent the human line, showed a relative decrease in body size and increase in brain size compared to great apes.

The authors say that these complex patterns urge a re-evaluation of the deeply rooted paradigm that comparing brain size to body size for any species provides a measure of the species’ intelligence.

Evolutionary tree of mammals – different colours represent groups of species that share a similar brain-to-body size relationship.

“At first sight, the importance of taking the evolutionary trajectory of body size into account may seem unimportant,” says Jeroen Smaers, an evolutionary biologist at Stony Brook University and first author on the study.

“After all, many of the big-brained mammals such as elephants, dolphins, and great apes also have a high brain-to-body size. But this is not always the case. The California sea lion, for example, has a low relative brain size, which lies in contrast to their remarkable intelligence.”

Associate Professor Vera Weisbecker, who participated in the research, said that the paper also proved an important point regarding marsupial mammals, such as koalas, kangaroos, or possums.

“Scientists are often prejudiced against marsupials. They are considered primitive and small-brained because they are born at tiny sizes and their brain mostly develops after birth. However, this study shows that marsupial brains have a similar relationship with body size as other mammals, such as bats, some rodents, and shrews”

By taking into account evolutionary history, the current study reveals that the California sea lion attained a low brain-to-body size because of the strong selective pressures on body size, most likely because aquatic carnivorans diversified into a semi-aquatic niche.

In other words, they have a low relative brain size because of selection on increased body size, not because of selection on decreased brain size.

“We’ve overturned a long-standing dogma that relative brain size can be equivocated with intelligence,” says Kamran Safi, a research scientist at the Max Planck Institute of Animal Behaviour and senior author on the study.

“Sometimes, relatively big brains can be the end result of a gradual decrease in body size to suit a new habitat or way of moving—in other words, nothing to do with intelligence at all. Using relative brain size as a proxy for cognitive capacity must be set against an animal’s evolutionary history and the nuances in the way brain and body have changed over the tree of life.”

The study further showed that most changes in brain size occurred after two cataclysmic events in Earth’s history: the mass extinction 66 million years ago and a climatic transition 23-33 million years ago.

After the mass extinction event at the end of the Cretaceous period, the researchers noticed a dramatic shift in brain-body scaling in lineages such as rodents, bats and carnivorans as animals radiated into the empty niches left by extinct dinosaurs.

Roughly 30 million years later, a cooling climate in the Late Paleogene led to more profound changes, with seals, bears, whales, and primates all undergoing evolutionary shifts in their brain and body size.

“A big surprise was that much of the variation in relative brain size of mammals that live today can be explained by changes that their ancestral lineages underwent following these cataclysmic events,” says Smaers.

This includes evolution of the biggest mammalian brains, such as the dolphins, elephants, and great apes, which all evolved their extreme proportions after the climate change event 23-33 million years ago.

The authors conclude that efforts to truly capture the evolution of intelligence will require increased effort examining neuroanatomical features, such as brain regions known for higher cognitive processes.


Animal Intelligence and the Evolution of the Human Mind

By Ursula Dicke and Gerard Roth

As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns. Only humans can perform such intellectual feats, presumably because we are smarter than all other animal species—at least by our own definition of intelligence.

Of course, intelligence must emerge from the workings of the three-pound mass of wetware packed inside our skulls. Thus, researchers have tried to identify unique features of the human brain that could account for our superior intellectual abilities. But, anatomically, the human brain is very similar to that of other primates because humans and chimpanzees share an ancestor that walked the earth less than seven million years ago.

Accordingly, the human brain contains no highly conspicuous characteristics that might account for the species’ cleverness. For instance, scientists have failed to find a correlation between absolute or relative brain size and acumen among humans and other animal species. Neither have they been able to discern a parallel between wits and the size or existence of specific regions of the brain, excepting perhaps Broca’s area, which governs speech in people. The lack of an obvious structural correlate to human intellect jibes with the idea that our intelligence may not be wholly unique: studies are revealing that chimps, among various other species, possess a diversity of humanlike social and cognitive skills.

Nevertheless, researchers have found some microscopic clues to humanity’s aptitude. We have more neurons in our brain’s cerebral cortex (its outermost layer) than other mammals do. The insulation around nerves in the human brain is also thicker than that of other species, enabling the nerves to conduct signals more rapidly. Such biological subtleties, along with behavioral ones, suggest that human intelligence is best likened to an upgrade of the cognitive capacities of nonhuman primates rather than an exceptionally advanced form of cognition.

Smart Species
Because animals cannot read or speak, their aptitude is difficult to discern, much less measure. Thus, comparative psychologists have invented behavior-based tests to assess birds’ and mammals’ abilities to learn and remember, to comprehend numbers and to solve practical problems. Animals of various stripes—but especially nonhuman primates—often earn high marks on such action-oriented IQ tests. During World War I, German psychologist Wolfgang Köhler, for example, showed that chimpanzees, when confronted with fruit hanging from a high ceiling, devised an ingenious way to get it: they stacked boxes to stand on to reach the fruit. They also constructed long sticks to reach food outside their enclosure. Researchers now know that great apes have a sophisticated understanding of tool use and construction.

Psychologists have used such behavioral tests to illuminate similar cognitive feats in other mammals as well as in birds. Pigeons can discriminate between male and female faces and among paintings by different artists they can also group pictures into categories such as trees, selecting those belonging to a category by pecking with their beaks, an action that often brings a food reward. Crows have intellectual capacities that are overturning conventional wisdom about the brain.

Behavioral ecologists, on the other hand, prefer to judge animals on their street smarts—that is, their ability to solve problems relevant to survival in their natural habitats—rather than on their test-taking talents. In this view, intelligence is a cluster of capabilities that evolved in response to particular environments. Some scientists have further proposed that mental or behavioral flexibility, the ability to come up with novel solutions to problems, is another good measure of animal intellect. Among birds, green herons occasionally throw an object in the water to lure curious fish—a trick that, ornithologists have observed, has been reinvented by groups of these animals living in distant locales. Even fish display remarkable practical intelligence, such as the use of tools, in the wild. Cichlid fish, for instance, use leaves as “baby carriages” for their egg masses.

Animals also can display humanlike social intelligence. Monkeys engage in deception, for example dolphins have been known to care for another injured pod member (displaying empathy), and a whale or porpoise may recognize itself in the mirror. Even some fish exhibit subtle kinds of social skills. Behavioral ecologist Redouan Bshary of the University of Neuchâtel in Switzerland and his colleagues described one such case in a 2006 paper. Bony fish such as the so-called cleaner wrasse (Labroides dimidiatus) cooperate and remove parasites from the skin of other fish or feed on their mucus. Bshary’s team found that bystander fish spent more time next to cleaners the bystanders had observed being cooperative than to other fish. Humans, the authors note, tend to notice altruistic behavior and are more willing to help do-gooders whom they have observed doing favors for others. Similarly, cleaner wrasses observe and evaluate the behavior of other finned ocean denizens and are more willing to help fish that they have seen assisting third parties.

From such studies, scientists have constructed evolutionary hierarchies of intelligence. Primates and cetaceans (whales, dolphins and porpoises) are considered the smartest mammals. Among primates, humans and apes are considered cleverer than monkeys, and monkeys more so than prosimians. Of the apes, chimpanzees and bonobos rank above gibbons, orangutans and gorillas. Dolphins and sperm whales are supposedly smarter than nonpredatory baleen whales such as blue whales. Among birds, scientists consider parrots, owls and corvids (crows and ravens) the brightest. Such a pecking order argues against the idea that intelligence evolved along a single path, culminating in human acumen. Instead intellect seems to have emerged independently in birds and mammals and also in cetaceans and primates.

Heavy Thoughts?
What about the brain might underlie these parallel paths to astuteness? One candidate is absolute brain size. Although many studies have linked brain mass with variations in human intelligence, size does not always correlate with smarts in different species. For example, clever small animals such as parrots, ravens, rats and relatively diminutive apes have brains of modest proportions, whereas some large animals such as horses and cows with large brains are comparatively dim-witted. Brain bulk cannot account for human intelligence either: At eight to nine kilograms, sperm and killer whale brains far outweigh the 1.4 kilograms of neural tissue inside our heads. As heavy as five kilograms, elephant brains are also much chunkier than ours.

Relative brain size—the ratio of brain to body mass—does not provide a satisfying explanation for interspecies differences in smarts either. Humans do compare favorably with many medium and large species: our brain makes up approximately 2 percent of our body weight, whereas the blue whale’s brain, for instance, is less than one 100th of a percent of its weight. But some tiny, not terribly bright animals such as shrews and squirrels win out in this measure. In general, small animals boast relatively large brains, and large animals harbor relatively small ones. Although absolute brain mass increases with body weight, brain mass as a proportion of body mass tends to decrease with rising body weight.

Another cerebral yardstick that scientists have tried to tie to intelligence is the degree of encephalization, measured by the encephalization quotient (EQ). The EQ expresses the extent to which a species’ relative brain weight deviates from the average in its animal class, say, mammal, bird or amphibian. Here the human brain tops the list: it is seven to eight times larger than would be expected for a mammal of its weight. But EQ does not parallel intellect perfectly either: gibbons and some capuchin monkeys have higher EQs than the more intelligent chimpanzees do, and even a few pro­sim­ians—the earliest evolved primates alive today—have higher EQs than gorillas do.

Or perhaps the size of the brain’s outermost layer, the cerebral cortex—the seat of many of our cognitive capacities—is the key. But it turns out that the dimensions of the cerebral cortex depend on those of the entire brain and that the size of the cortex constitutes no better arbiter of a superior mind. The same is true for the prefrontal cortex, the hub of reason and action planning. Although some brain researchers have claimed in the past that the human prefrontal cortex is exceptionally large, recent studies have shown that it is not. The size of this structure in hu­mans is comparable to its size in other ­primates and may even be relatively small as compared with its counterpart in elephants and cetaceans.

The lack of a large-scale measure of the human brain that could explain our performance may reflect the idea that human intellect may not be totally inimitable. Apes, after all, understand cause and effect, make and use tools, produce and comprehend language, and lie to and imitate others. These primates may even possess a theory of mind—the ability to understand another animal’s mental state and use it to guide their own behavior. Whales, dolphins and even some birds boast some of these mental talents as well. Thus, adult humans may simply be more intuitive and facile with tools and language than other species are, as opposed to possessing unique cognitive skills.

Networking
Fittingly, researchers have found the best correlates for intelligence by looking at a much smaller scale. Brains consist of nerve cells, or neurons, and supporting cells called glia. The more neurons, the more extensive and more productive the neuronal networks can be—and those networks determine varied brain functions, including perception, memory, planning and thinking. Large brains do not automatically have more neurons in fact, neuronal density generally decreases with increasing brain size because of the additional glial cells and blood vessels needed to support a big brain.

Humans have 11.5 billion cortical neurons—more than any other mammal, because of the human brain’s high neuronal density. Humans have only about half a billion more cortical neurons than whales and elephants do, however—not enough to account for the significant cognitive differences between humans and these species. In addition, however, a brain’s information-processing capacity depends on how fast its nerves conduct electrical impulses. The most rapidly conducting nerves are swathed in sheaths of insulation called myelin. The thicker a nerve’s myelin sheath, the faster the neural impulses travel along that nerve. The myelinated nerves in the brains of whales and elephants are demonstrably thinner than they are in primates, suggesting that information travels faster in the human brain than it does in the brains of nonprimates.

What is more, neuronal messages must travel longer distances in the relatively large brains of elephants and whales than they do in the more compact human brain. The resulting boost in information-processing speed may at least partly explain the disparity in aptitude between humans and other big-brained creatures.

Among humans’ cerebral advantages, language may be the most obvious. Various animals can convey complex messages to other members of their species they can communicate about objects that are not in sight and relay information about individuals and events. Chimpanzees, gorillas, dolphins and parrots can even understand and use human speech, gestures or symbols in constructions of up to about three words. But even after years of training, none of these creatures develops verbal skills more advanced than those of a three-year-old child.

In humans, grammar and vocabulary all but explode at age three. This timing corresponds with the development of Broca’s speech area in the left frontal lobe, which may be unique to humans. That is, scientists are unsure whether a direct precursor to this speech region exists in the nonhuman primate brain. The absence of an intricately wired language region in the brains of other species may explain why, of all animals, humans alone have a language that contains complex grammar. Researchers date the development of human grammar and syntax to between 80,000 and 100,000 years ago, which makes it a relatively recent evolutionary advance. It was also one that probably greatly enhanced human intellect.


Beyond the two cultures: rethinking science and the humanities

Cross-disciplinary cooperation is needed to save civilization.

  • There is a great disconnect between the sciences and the humanities.
  • Solutions to most of our real-world problems need both ways of knowing.
  • Moving beyond the two-culture divide is an essential step to ensure our project of civilization.

For the past five years, I ran the Institute for Cross-Disciplinary Engagement at Dartmouth, an initiative sponsored by the John Templeton Foundation. Our mission has been to find ways to bring scientists and humanists together, often in public venues or — after Covid-19 — online, to discuss questions that transcend the narrow confines of a single discipline.

It turns out that these questions are at the very center of the much needed and urgent conversation about our collective future. While the complexity of the problems we face asks for a multi-cultural integration of different ways of knowing, the tools at hand are scarce and mostly ineffective. We need to rethink and learn how to collaborate productively across disciplinary cultures.


Arriving At The Table

The Gartner Hype Cycle is often referenced in the ADAS and engineering community as a representation of where we are right now in terms of autonomous driving. As we transition from the Trough of Disillusionment and into the Slope of Enlightenment, there is ample opportunity to merge cognitive brain science with the engineering disciplines required for the design and development of future mobility solutions.

This is, as Dr. López-González suggests, the time to &ldquopump the brakes,&rdquo and make sure we understand the critical differences between vehicle perception and vehicle cognition. Perhaps now is the time to consider that machine intelligence may benefit from a dose of human intellect by way of brain-inspired computing.

&ldquoImagine if we had everybody sitting around a table talking about this,&rdquo Dr. López-González said. &ldquoI think we&rsquoll get the answer.&rdquo


Did rapid brain evolution make humans susceptible to Alzheimers?

The puzzling question, Prof. Bruce Yankner said, is why humans develop the severe disabilities of Alzheimer’s disease.

(PhysOrg.com) -- Of the millions of animals on Earth, including the relative handful that are considered the most intelligent -- including apes, whales, crows, and owls -- only humans experience the severe age-related decline in mental abilities marked by Alzheimer's disease.

To Bruce Yankner, professor of pathology and neurology at Harvard Medical School (HMS), it’s pretty clear that evolution is to blame.

“Something has occurred in evolution that makes our brain susceptible to age-related change,” Yankner said in a talk last night sponsored by the Harvard Museum of Natural History as part of its “Evolution Matters” lecture series.

Yankner, whose HMS lab studies brain aging and how getting old gives rise to the pathology of Alzheimer’s and Parkinson’s diseases, said Alzheimer’s is one of the most rapidly emerging diseases of this century. As medical science lengthens human lifespan, the proportion of the population that is elderly is growing. Considering that as many as half of those over age 85 develop Alzheimer’s, there is a growing urgency to understand the disease more fully and to develop more effective interventions.

“It is clear that cognitive impairment and decline is one of the emerging health threats of the 21st century,” Yankner said.

Yankner said that scientific evidence shows that some cognitive decline — beginning in middle age and accelerating after age 70 — is normal as we grow older. This decline is also seen in other animals, including mice and monkeys. It is marked by wide variation among individuals, with some individuals maintaining cognitive abilities similar to those much younger.

The puzzling question, Yankner said, is why humans develop the severe disabilities of Alzheimer’s disease. Studies of other creatures show no sign of similar conditions even in our closest animal relatives. That means susceptibility to Alzheimer’s evolved recently, likely during a period marked by a rapid increase in our brain size. Size alone probably isn’t the determining factor, though, Yankner said, since other animals are known to have even larger brains, including whales, elephants, and even our extinct relative the Neanderthal.

Instead, he said, it is likely that brain complexity and the new large number of cells in the human brain have something to do with it.

Recent research, in Yankner’s lab and elsewhere, has used genetic tools to probe the differences between young and old brains in humans, monkeys, and mice. The work shows that gene function in the aging brain slows — dramatically in ones with Alzheimer’s — and that the genes that shut off the most are those that protect the brain against genetic damage from environmental and other factors.

Yankner said he believes that cognitive decline is due to a slow accumulation of genetic damage in the aging brain, with Alzheimer’s showing the most severe form of this damage, called double strand breaks. Though the source of the damage is not yet clear, one culprit, he said, may be the accumulation of metals in the brain over time, particularly iron.

Neurons use more energy than most other cells, Yankner said. With the brain’s increase in complexity over time, its energy demands also rose. Iron plays a key role in a cell’s energy-producing mitochondria, and so iron accumulation leading to genetic damage could be a byproduct of our neuron-rich, energy-gobbling brains.

“Aging is a balance between wear and tear and repair. Where you wind up in that balance determines how you do,” Yankner said.


7 Scientific Studies About How Animals React to Music

Music is pretty universally enjoyed . when it comes to people. Animals, on the other hand, have diverse reactions to tunes. For every Ronan the head-bopping sea lion, there are plenty of creatures that can't keep the beat. Here are seven scientific discoveries about how some animals react to music, either created by humans or themselves.

1. DOGS IN KENNELS MIGHT BE LESS STRESSED WHILE LISTENING TO CLASSICAL MUSIC.

In a 2012 study [PDF] published in The Journal of Veterinary Behavior, researchers from Colorado State University monitored the behavior of 117 kenneled dogs, including their activity levels, vocalization, and body shaking. The researchers played a few different types of music to the dogs, including classical, heavy metal, and an altered type of classical music. They also observed the dogs' behavior when no music was playing at all. They found that the dogs slept the most while listening to all kinds of classical music, indicating that it helped them relax. The dogs had the opposite reaction to the metal music, which provoked increased body shaking—a sign of nervousness.

The researchers noted the similarities between dogs and people when it comes to classical music. “These results are consistent with human studies, which have suggested that music can reduce agitation, promote sleep, improve mood, and lower stress and anxiety,” they wrote. They also point out that heavy metal music has anxiety-inducing effects on some people as well.

2. CATS DON'T CARE ABOUT HUMAN MUSIC, BUT SCIENTISTS ARE ABLE TO CREATE MUSIC THAT THEY DO ENJOY.

Cats either don't care for, or are pretty indifferent to, human music. Thankfully, Charles Snowdon, a psychologist at the University of Wisconsin-Madison, David Teie, a composer at the University of Maryland, and Megan Savage, formerly of the University of Wisconsin-Madison and now a Ph.D. student at SUNY-Binghamton, have developed music that contains frequencies and tempos similar to the ones cats use to communicate. We tested some of the songs on one of our editor's cats earlier this year you can listen to samples of the songs here.

Snowdon and Savage went to 47 households with cats and played them music, including two classical songs and two songs developed for felines. When the researchers played the latter, the cat was more likely to move towards the speaker, or even rub up against it, according to their study, which was published in the journal Applied Animal Behavior Science earlier this year. Interestingly, young and old cats reacted to the cat songs the most positively. Middle-aged cats showed more indifference.

3. IT'S ALSO POSSIBLE TO MAKE MONKEY MUSIC.

Cats weren't the first animals Snowdon, Savage, and Teie made species-specific music for. In 2009, they developed songs that mirrored the pitch of monkey calls. For their study, which was published in the journal Biology Letters, the scientists played the music for tamarin monkeys. Songs that were inspired by the calming calls the animals make caused the monkeys to relax they even ate more while listening to those songs. But when the researchers played music that contained sounds similar to ones the monkeys make when they’re expressing fear, the monkeys became agitated. (You can listen to the songs here.) The monkeys were mostly indifferent to human music—their behavior didn't noticeably change when they were listening to Nine Inch Nails, Tool, or Samuel Barber. But, interestingly, when they heard “Of Wolf and Man” by Metallica, they grew calmer.

4. COWS PRODUCE MORE MILK WHEN THEY'RE LISTENING TO RELAXING MUSIC.

In 2001, researchers at the University of Leicester played various songs to 1000-strong herds of Friesian dairy cows. Over a period of nine weeks, the researchers alternated between fast music, slow music, and silence for 12 hours each day. They found that calming music—like R.E.M.'s "Everybody Hurts," Simon & Garfunkel's "Bridge Over Troubled Water," and Beethoven's "Pastoral Symphony"—actually resulted in the cows producing 3 percent more milk—0.73 liters per cow per day. One of the lead researchers, Dr. Adrian North, told the BBC, “Calming music can improve milk yield, probably because it reduces stress.” The cows were not so into “Space Cowboy” by Jamiroquai or “Size of a Cow” by Wonderstuff.

5. ELEPHANTS MIGHT BE BETTER AT PLAYING MUSIC THAN HUMANS ARE.

Elephants are already known for their ability to paint with their trunks, but it turns out that they might be musically inclined as well. (Just check out this viral video of elephants swaying their trunks to violin music!) In northern Thailand, a conservationist named Richard Lair put together the Thai Elephant Orchestra, in which 16 elephants play specially developed instruments like steel drums and even harmonicas. Neuroscientists who have studied the music of the Thai Elephant Orchestra have determined that the animals are able to keep a very stable tempo on a large drum—even more stable than a human can.

6. BIRD BRAINS REACT TO MUSIC IN A MANNER SIMILAR TO HUMAN BRAINS.

Birds are probably the most well-known singers of the animal kingdom. A few years ago, researchers at Emory University set out to learn whether birds are actually making music, like humans do. To find out, they examined the brains of both male and female white-tailed sparrows as they listened to the sounds of male birds.

When humans listen to music, our amygdalae often light up in response. It turned out that female white-tailed sparrows had similar brain responses to the bird sounds. The part of their brain that’s similar to the amygdala lit up while listening to the male’s song. The male birds, on the other hand, had brain reactions similar to when humans listen to music they don’t like. Sarah Earp, the study's lead researcher, explained, “We found that the same neural reward system is activated in female birds in the breeding state that are listening to male birdsong, and in people listening to music that they like.”

7. FISH KNOW THE DIFFERENCE BETWEEN COMPOSERS.

In 2013, a study was published in the journal Behavioral Processes that revealed that goldfish could be trained to distinguish between composers. Researchers at Keio University used pieces of music by two composers in the study: Igor Stravinsky and Johann Sebastian Bach. The goal was to train the goldfish to gnaw on a ball filled with food when the correct composer’s music was playing. One group of fish got Stravinsky and a separate group got Bach. When the fish heard music, they went to gnaw on the ball and were rewarded with food. Once the fish were correlating a composer’s music with the reward, the researchers tried playing the other composer’s music. The goldfish didn’t gnaw on the ball at that point, indicating that they knew enough about the pitch and timbre of their composer to not associate the novel music with food.


This is How You Study The Evolution of Animal Intelligence

There are many scientists who study the mental abilities of animals. As intelligent animals ourselves, we’re keen to learn whether other species share our skills, and how our vaunted smarts evolved. We see study after study about whether chimpanzees care about fairness, whether pigeons outsmart humans at a classic maths problem, whether cuttlefish can remember where, what and when, or whether (and how) parrots and crows use tools,

But animals are hard to work with. You need to design tests that objectively assess their mental skills without raising the spectre of anthropomorphism, and you need to carefully train them to perform those tests. These difficulties mean that researchers mostly resort to small experiments with just one species, often with their own bespoke tasks. This makes it very hard to compare species or pool the results of separate studies. If a lemur behaves differently to a monkey in separate experiments, is it because of some genuine biological difference, or some quirk of the respective studies?

These problems mean that the study of animal intelligence is rich but piecemeal. Each study adds a new piece to the jigsaw, but is everyone even solving the same puzzle?

Evan MacLean, Brian Hare, and Charles Nunn from Duke University have had enough. They led a international team of 58 scientists from 25 institutes in studying the evolution of one mental skill—self-control—in 567 animals from 36 species.

Chimpanzees, gorillas, baboons, marmosets, lemurs, squirrels, dogs, elephants, pigeons, parrots and more tried their hands (or trunks or beaks or snouts) at the same two tasks. “It was literally a mouse-to-elephant study,” says MacLean, “or at least a Mongolian-gerbil-to-elephant study.”

“I think it’s really showing the future of the field of cognition,” says Karin Isler from the Universtiy of Zurich. “Instead of just giving glimpses and suggestions, and sometimes contradicting evidence, one can find convincing explanations for the evolution of cognitive abilities.”

The team focused on self-control—the ability to stop doing that, put that down, eat that later. Animals exercise it when they stop themselves from mating in the presence of a dominant peer, when they forgo an existing source of food in favour of foraging somewhere new, or when they share resources with their fellows. In humans, a child’s degree of self-control correlates with their health, wealth, and mental state as adults. It’s important.

It’s also easy to measure. Swiss psychologist Jean Piaget did it in the 1950s when he repeatedly put a toy under a box in front of some infants, and then moved it to a second box. He found that babies under 10 months of age would keep on searching under Box A, despite what they had seen. They couldn’t resist their old habit to do something flexible and different that ability only kicks in around our first birthday. MacLean, Hare and Nunn’s team gave this “A-not-B” test to their animals, using food rather than a toy.

They also tried a second task, where animals had to reach round the side of an opaque cylinder to get at food within. The team then swapped the opaque cylinder for a transparent one. Now, the animals had to hold back their natural instinct to reach directly for the food (which would have knocked the cylinder over), and go around as before.

The team tested all their animals on one or both tasks, and compared their performance to traits like brain size or group size. They found a few surprises. For example, the animals’ scores correlated with the absolute but not relative sizes of their brains. In other words, it didn’t matter whether the animals’ brains were big for their size, but whether they were big, full-stop.

“That’s funny because brain size and body size scale predictably. Big animals have big brains,” says MacLean. As such, many scientists believed that relative brain size mattered more. There’s even a measure called the encephalization quotient (EQ) that estimates intelligence by comparing an animal’s brain to that of a typical creature of the same size. And yet, for self-control at least, it’s absolute size that’s important. That was true whether they looked at all their 36 species, or just at the primates.

“That makes sense,” says Richard Byrne at the University of St Andrews. “If the brain is, to some extent, an on-board computer, it will be the number of components that determine its power [rather than] the size of the carrying case or body.”

The team also tested two leading explanations for the evolution of primate intelligence. One idea says that our smarts evolved so we could keep track of the relationships within our complex social groups. Indeed, you can make a decent guess about the size of community that a primate lives in by measuring the size of its skull. But the team found no link between group size and performance in their tasks. “That surprised us,” says MacLean. “It’s such a popular hypothesis but we found no evidence for it.”

Instead, the team found more support for a second idea: that primate intelligence was driven by the need to keep track of a wide range of food like fruit, which vary by place and season. They showed that the variety in the animals’ diets (but not the proportion of fruit) was indeed linked to self-control. Together, these two factors—absolute brain size and dietary breadth—explained around 82 percent of the variations in the primates’ scores.

“The nice thing about the tasks is that, because of their simplicity, they are very unlikely to depend a lot on species-specific aptitudes unrelated to cognition or to prior experience,” says Byrne. “I’d trust the results.”

But Robin Dunbar from the University of Oxford felt that the team’s conclusions are “misguided and naive” because their tasks weren’t a good measure of self-control, at least in any sense that matters in an animal’s social life. Instead they were “straight ecological or foraging tasks and nothing more, so it’s not awfully surprising that it correlates with diet,” he says.

Brain-scanning studies in humans and monkeys have also found links between the size of specific brain regions, size of social groups, and social skills. “It seems bizarre to be running an analysis against measures of total brain size,” says Dunbar.

Of course, this study just looked at one aspect of animal psychology, among many. The team found that the animals’ scores on the self-control tests did correlate with reports of other skills, like innovation, tool use, deception, and social learning. But MacLean suspects that if other teams focused on these skills, they would find different results. Group size may become more important if researchers focused on tasks that looked at social learning—the ability to imitate and learn from others. Alternatively, diet may again win out if scientists looked at memory skills.

This new study doesn’t settle the debates. It just points to a way forward. Each of the scientists in the team could easily have published their own papers using the collected data, but they decided to combine their efforts into one publication. “We thought it would be most powerful if it came out together,” says MacLean. “There’s never been a data set this size. We’re certainly hoping that it’s a game-changer in the way we do comparative psychology.”

And even Dunbar says, “It’s good to see comparative studies of this kind being done at last, and it’s very worthy that they have done the same task on many species.”


Did rapid brain evolution make humans susceptible to Alzheimers?

The puzzling question, Prof. Bruce Yankner said, is why humans develop the severe disabilities of Alzheimer’s disease.

(PhysOrg.com) -- Of the millions of animals on Earth, including the relative handful that are considered the most intelligent -- including apes, whales, crows, and owls -- only humans experience the severe age-related decline in mental abilities marked by Alzheimer's disease.

To Bruce Yankner, professor of pathology and neurology at Harvard Medical School (HMS), it’s pretty clear that evolution is to blame.

“Something has occurred in evolution that makes our brain susceptible to age-related change,” Yankner said in a talk last night sponsored by the Harvard Museum of Natural History as part of its “Evolution Matters” lecture series.

Yankner, whose HMS lab studies brain aging and how getting old gives rise to the pathology of Alzheimer’s and Parkinson’s diseases, said Alzheimer’s is one of the most rapidly emerging diseases of this century. As medical science lengthens human lifespan, the proportion of the population that is elderly is growing. Considering that as many as half of those over age 85 develop Alzheimer’s, there is a growing urgency to understand the disease more fully and to develop more effective interventions.

“It is clear that cognitive impairment and decline is one of the emerging health threats of the 21st century,” Yankner said.

Yankner said that scientific evidence shows that some cognitive decline — beginning in middle age and accelerating after age 70 — is normal as we grow older. This decline is also seen in other animals, including mice and monkeys. It is marked by wide variation among individuals, with some individuals maintaining cognitive abilities similar to those much younger.

The puzzling question, Yankner said, is why humans develop the severe disabilities of Alzheimer’s disease. Studies of other creatures show no sign of similar conditions even in our closest animal relatives. That means susceptibility to Alzheimer’s evolved recently, likely during a period marked by a rapid increase in our brain size. Size alone probably isn’t the determining factor, though, Yankner said, since other animals are known to have even larger brains, including whales, elephants, and even our extinct relative the Neanderthal.

Instead, he said, it is likely that brain complexity and the new large number of cells in the human brain have something to do with it.

Recent research, in Yankner’s lab and elsewhere, has used genetic tools to probe the differences between young and old brains in humans, monkeys, and mice. The work shows that gene function in the aging brain slows — dramatically in ones with Alzheimer’s — and that the genes that shut off the most are those that protect the brain against genetic damage from environmental and other factors.

Yankner said he believes that cognitive decline is due to a slow accumulation of genetic damage in the aging brain, with Alzheimer’s showing the most severe form of this damage, called double strand breaks. Though the source of the damage is not yet clear, one culprit, he said, may be the accumulation of metals in the brain over time, particularly iron.

Neurons use more energy than most other cells, Yankner said. With the brain’s increase in complexity over time, its energy demands also rose. Iron plays a key role in a cell’s energy-producing mitochondria, and so iron accumulation leading to genetic damage could be a byproduct of our neuron-rich, energy-gobbling brains.

“Aging is a balance between wear and tear and repair. Where you wind up in that balance determines how you do,” Yankner said.


Arriving At The Table

The Gartner Hype Cycle is often referenced in the ADAS and engineering community as a representation of where we are right now in terms of autonomous driving. As we transition from the Trough of Disillusionment and into the Slope of Enlightenment, there is ample opportunity to merge cognitive brain science with the engineering disciplines required for the design and development of future mobility solutions.

This is, as Dr. López-González suggests, the time to &ldquopump the brakes,&rdquo and make sure we understand the critical differences between vehicle perception and vehicle cognition. Perhaps now is the time to consider that machine intelligence may benefit from a dose of human intellect by way of brain-inspired computing.

&ldquoImagine if we had everybody sitting around a table talking about this,&rdquo Dr. López-González said. &ldquoI think we&rsquoll get the answer.&rdquo


How mammals evolved bigger brains

Scientists have pieced together a timeline of how brain and body size evolved in mammals over the last 150 million years by comparing the brain mass of 1400 living and extinct mammals.

For the 107 fossils examined, among them ancient whales and the oldest Old-World monkey skull ever found, they used endocranial volume data from skulls instead of brain mass data.

The brain measurements were then analysed along with body size to compare the scale of brain size to body size over deep evolutionary time.

The findings, published in Science Advances, showed that brain size relative to body size—long considered an indicator of animal intelligence—has not followed a stable scale over evolutionary time.

Famous “big-brained” humans, dolphins, and elephants, for example, attained their proportions in different ways. Elephants increased in body size, but surprisingly, even more in brain size. Dolphins, on the other hand, generally decreased their body size while increasing brain size. Great apes showed a wide variety of body sizes, with a general trend towards increases in brain and body size.

In comparison, ancestral hominins, which represent the human line, showed a relative decrease in body size and increase in brain size compared to great apes.

The authors say that these complex patterns urge a re-evaluation of the deeply rooted paradigm that comparing brain size to body size for any species provides a measure of the species’ intelligence.

Evolutionary tree of mammals – different colours represent groups of species that share a similar brain-to-body size relationship.

“At first sight, the importance of taking the evolutionary trajectory of body size into account may seem unimportant,” says Jeroen Smaers, an evolutionary biologist at Stony Brook University and first author on the study.

“After all, many of the big-brained mammals such as elephants, dolphins, and great apes also have a high brain-to-body size. But this is not always the case. The California sea lion, for example, has a low relative brain size, which lies in contrast to their remarkable intelligence.”

Associate Professor Vera Weisbecker, who participated in the research, said that the paper also proved an important point regarding marsupial mammals, such as koalas, kangaroos, or possums.

“Scientists are often prejudiced against marsupials. They are considered primitive and small-brained because they are born at tiny sizes and their brain mostly develops after birth. However, this study shows that marsupial brains have a similar relationship with body size as other mammals, such as bats, some rodents, and shrews”

By taking into account evolutionary history, the current study reveals that the California sea lion attained a low brain-to-body size because of the strong selective pressures on body size, most likely because aquatic carnivorans diversified into a semi-aquatic niche.

In other words, they have a low relative brain size because of selection on increased body size, not because of selection on decreased brain size.

“We’ve overturned a long-standing dogma that relative brain size can be equivocated with intelligence,” says Kamran Safi, a research scientist at the Max Planck Institute of Animal Behaviour and senior author on the study.

“Sometimes, relatively big brains can be the end result of a gradual decrease in body size to suit a new habitat or way of moving—in other words, nothing to do with intelligence at all. Using relative brain size as a proxy for cognitive capacity must be set against an animal’s evolutionary history and the nuances in the way brain and body have changed over the tree of life.”

The study further showed that most changes in brain size occurred after two cataclysmic events in Earth’s history: the mass extinction 66 million years ago and a climatic transition 23-33 million years ago.

After the mass extinction event at the end of the Cretaceous period, the researchers noticed a dramatic shift in brain-body scaling in lineages such as rodents, bats and carnivorans as animals radiated into the empty niches left by extinct dinosaurs.

Roughly 30 million years later, a cooling climate in the Late Paleogene led to more profound changes, with seals, bears, whales, and primates all undergoing evolutionary shifts in their brain and body size.

“A big surprise was that much of the variation in relative brain size of mammals that live today can be explained by changes that their ancestral lineages underwent following these cataclysmic events,” says Smaers.

This includes evolution of the biggest mammalian brains, such as the dolphins, elephants, and great apes, which all evolved their extreme proportions after the climate change event 23-33 million years ago.

The authors conclude that efforts to truly capture the evolution of intelligence will require increased effort examining neuroanatomical features, such as brain regions known for higher cognitive processes.


Beyond the two cultures: rethinking science and the humanities

Cross-disciplinary cooperation is needed to save civilization.

  • There is a great disconnect between the sciences and the humanities.
  • Solutions to most of our real-world problems need both ways of knowing.
  • Moving beyond the two-culture divide is an essential step to ensure our project of civilization.

For the past five years, I ran the Institute for Cross-Disciplinary Engagement at Dartmouth, an initiative sponsored by the John Templeton Foundation. Our mission has been to find ways to bring scientists and humanists together, often in public venues or — after Covid-19 — online, to discuss questions that transcend the narrow confines of a single discipline.

It turns out that these questions are at the very center of the much needed and urgent conversation about our collective future. While the complexity of the problems we face asks for a multi-cultural integration of different ways of knowing, the tools at hand are scarce and mostly ineffective. We need to rethink and learn how to collaborate productively across disciplinary cultures.


7 Scientific Studies About How Animals React to Music

Music is pretty universally enjoyed . when it comes to people. Animals, on the other hand, have diverse reactions to tunes. For every Ronan the head-bopping sea lion, there are plenty of creatures that can't keep the beat. Here are seven scientific discoveries about how some animals react to music, either created by humans or themselves.

1. DOGS IN KENNELS MIGHT BE LESS STRESSED WHILE LISTENING TO CLASSICAL MUSIC.

In a 2012 study [PDF] published in The Journal of Veterinary Behavior, researchers from Colorado State University monitored the behavior of 117 kenneled dogs, including their activity levels, vocalization, and body shaking. The researchers played a few different types of music to the dogs, including classical, heavy metal, and an altered type of classical music. They also observed the dogs' behavior when no music was playing at all. They found that the dogs slept the most while listening to all kinds of classical music, indicating that it helped them relax. The dogs had the opposite reaction to the metal music, which provoked increased body shaking—a sign of nervousness.

The researchers noted the similarities between dogs and people when it comes to classical music. “These results are consistent with human studies, which have suggested that music can reduce agitation, promote sleep, improve mood, and lower stress and anxiety,” they wrote. They also point out that heavy metal music has anxiety-inducing effects on some people as well.

2. CATS DON'T CARE ABOUT HUMAN MUSIC, BUT SCIENTISTS ARE ABLE TO CREATE MUSIC THAT THEY DO ENJOY.

Cats either don't care for, or are pretty indifferent to, human music. Thankfully, Charles Snowdon, a psychologist at the University of Wisconsin-Madison, David Teie, a composer at the University of Maryland, and Megan Savage, formerly of the University of Wisconsin-Madison and now a Ph.D. student at SUNY-Binghamton, have developed music that contains frequencies and tempos similar to the ones cats use to communicate. We tested some of the songs on one of our editor's cats earlier this year you can listen to samples of the songs here.

Snowdon and Savage went to 47 households with cats and played them music, including two classical songs and two songs developed for felines. When the researchers played the latter, the cat was more likely to move towards the speaker, or even rub up against it, according to their study, which was published in the journal Applied Animal Behavior Science earlier this year. Interestingly, young and old cats reacted to the cat songs the most positively. Middle-aged cats showed more indifference.

3. IT'S ALSO POSSIBLE TO MAKE MONKEY MUSIC.

Cats weren't the first animals Snowdon, Savage, and Teie made species-specific music for. In 2009, they developed songs that mirrored the pitch of monkey calls. For their study, which was published in the journal Biology Letters, the scientists played the music for tamarin monkeys. Songs that were inspired by the calming calls the animals make caused the monkeys to relax they even ate more while listening to those songs. But when the researchers played music that contained sounds similar to ones the monkeys make when they’re expressing fear, the monkeys became agitated. (You can listen to the songs here.) The monkeys were mostly indifferent to human music—their behavior didn't noticeably change when they were listening to Nine Inch Nails, Tool, or Samuel Barber. But, interestingly, when they heard “Of Wolf and Man” by Metallica, they grew calmer.

4. COWS PRODUCE MORE MILK WHEN THEY'RE LISTENING TO RELAXING MUSIC.

In 2001, researchers at the University of Leicester played various songs to 1000-strong herds of Friesian dairy cows. Over a period of nine weeks, the researchers alternated between fast music, slow music, and silence for 12 hours each day. They found that calming music—like R.E.M.'s "Everybody Hurts," Simon & Garfunkel's "Bridge Over Troubled Water," and Beethoven's "Pastoral Symphony"—actually resulted in the cows producing 3 percent more milk—0.73 liters per cow per day. One of the lead researchers, Dr. Adrian North, told the BBC, “Calming music can improve milk yield, probably because it reduces stress.” The cows were not so into “Space Cowboy” by Jamiroquai or “Size of a Cow” by Wonderstuff.

5. ELEPHANTS MIGHT BE BETTER AT PLAYING MUSIC THAN HUMANS ARE.

Elephants are already known for their ability to paint with their trunks, but it turns out that they might be musically inclined as well. (Just check out this viral video of elephants swaying their trunks to violin music!) In northern Thailand, a conservationist named Richard Lair put together the Thai Elephant Orchestra, in which 16 elephants play specially developed instruments like steel drums and even harmonicas. Neuroscientists who have studied the music of the Thai Elephant Orchestra have determined that the animals are able to keep a very stable tempo on a large drum—even more stable than a human can.

6. BIRD BRAINS REACT TO MUSIC IN A MANNER SIMILAR TO HUMAN BRAINS.

Birds are probably the most well-known singers of the animal kingdom. A few years ago, researchers at Emory University set out to learn whether birds are actually making music, like humans do. To find out, they examined the brains of both male and female white-tailed sparrows as they listened to the sounds of male birds.

When humans listen to music, our amygdalae often light up in response. It turned out that female white-tailed sparrows had similar brain responses to the bird sounds. The part of their brain that’s similar to the amygdala lit up while listening to the male’s song. The male birds, on the other hand, had brain reactions similar to when humans listen to music they don’t like. Sarah Earp, the study's lead researcher, explained, “We found that the same neural reward system is activated in female birds in the breeding state that are listening to male birdsong, and in people listening to music that they like.”

7. FISH KNOW THE DIFFERENCE BETWEEN COMPOSERS.

In 2013, a study was published in the journal Behavioral Processes that revealed that goldfish could be trained to distinguish between composers. Researchers at Keio University used pieces of music by two composers in the study: Igor Stravinsky and Johann Sebastian Bach. The goal was to train the goldfish to gnaw on a ball filled with food when the correct composer’s music was playing. One group of fish got Stravinsky and a separate group got Bach. When the fish heard music, they went to gnaw on the ball and were rewarded with food. Once the fish were correlating a composer’s music with the reward, the researchers tried playing the other composer’s music. The goldfish didn’t gnaw on the ball at that point, indicating that they knew enough about the pitch and timbre of their composer to not associate the novel music with food.


Animal Intelligence and the Evolution of the Human Mind

By Ursula Dicke and Gerard Roth

As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns. Only humans can perform such intellectual feats, presumably because we are smarter than all other animal species—at least by our own definition of intelligence.

Of course, intelligence must emerge from the workings of the three-pound mass of wetware packed inside our skulls. Thus, researchers have tried to identify unique features of the human brain that could account for our superior intellectual abilities. But, anatomically, the human brain is very similar to that of other primates because humans and chimpanzees share an ancestor that walked the earth less than seven million years ago.

Accordingly, the human brain contains no highly conspicuous characteristics that might account for the species’ cleverness. For instance, scientists have failed to find a correlation between absolute or relative brain size and acumen among humans and other animal species. Neither have they been able to discern a parallel between wits and the size or existence of specific regions of the brain, excepting perhaps Broca’s area, which governs speech in people. The lack of an obvious structural correlate to human intellect jibes with the idea that our intelligence may not be wholly unique: studies are revealing that chimps, among various other species, possess a diversity of humanlike social and cognitive skills.

Nevertheless, researchers have found some microscopic clues to humanity’s aptitude. We have more neurons in our brain’s cerebral cortex (its outermost layer) than other mammals do. The insulation around nerves in the human brain is also thicker than that of other species, enabling the nerves to conduct signals more rapidly. Such biological subtleties, along with behavioral ones, suggest that human intelligence is best likened to an upgrade of the cognitive capacities of nonhuman primates rather than an exceptionally advanced form of cognition.

Smart Species
Because animals cannot read or speak, their aptitude is difficult to discern, much less measure. Thus, comparative psychologists have invented behavior-based tests to assess birds’ and mammals’ abilities to learn and remember, to comprehend numbers and to solve practical problems. Animals of various stripes—but especially nonhuman primates—often earn high marks on such action-oriented IQ tests. During World War I, German psychologist Wolfgang Köhler, for example, showed that chimpanzees, when confronted with fruit hanging from a high ceiling, devised an ingenious way to get it: they stacked boxes to stand on to reach the fruit. They also constructed long sticks to reach food outside their enclosure. Researchers now know that great apes have a sophisticated understanding of tool use and construction.

Psychologists have used such behavioral tests to illuminate similar cognitive feats in other mammals as well as in birds. Pigeons can discriminate between male and female faces and among paintings by different artists they can also group pictures into categories such as trees, selecting those belonging to a category by pecking with their beaks, an action that often brings a food reward. Crows have intellectual capacities that are overturning conventional wisdom about the brain.

Behavioral ecologists, on the other hand, prefer to judge animals on their street smarts—that is, their ability to solve problems relevant to survival in their natural habitats—rather than on their test-taking talents. In this view, intelligence is a cluster of capabilities that evolved in response to particular environments. Some scientists have further proposed that mental or behavioral flexibility, the ability to come up with novel solutions to problems, is another good measure of animal intellect. Among birds, green herons occasionally throw an object in the water to lure curious fish—a trick that, ornithologists have observed, has been reinvented by groups of these animals living in distant locales. Even fish display remarkable practical intelligence, such as the use of tools, in the wild. Cichlid fish, for instance, use leaves as “baby carriages” for their egg masses.

Animals also can display humanlike social intelligence. Monkeys engage in deception, for example dolphins have been known to care for another injured pod member (displaying empathy), and a whale or porpoise may recognize itself in the mirror. Even some fish exhibit subtle kinds of social skills. Behavioral ecologist Redouan Bshary of the University of Neuchâtel in Switzerland and his colleagues described one such case in a 2006 paper. Bony fish such as the so-called cleaner wrasse (Labroides dimidiatus) cooperate and remove parasites from the skin of other fish or feed on their mucus. Bshary’s team found that bystander fish spent more time next to cleaners the bystanders had observed being cooperative than to other fish. Humans, the authors note, tend to notice altruistic behavior and are more willing to help do-gooders whom they have observed doing favors for others. Similarly, cleaner wrasses observe and evaluate the behavior of other finned ocean denizens and are more willing to help fish that they have seen assisting third parties.

From such studies, scientists have constructed evolutionary hierarchies of intelligence. Primates and cetaceans (whales, dolphins and porpoises) are considered the smartest mammals. Among primates, humans and apes are considered cleverer than monkeys, and monkeys more so than prosimians. Of the apes, chimpanzees and bonobos rank above gibbons, orangutans and gorillas. Dolphins and sperm whales are supposedly smarter than nonpredatory baleen whales such as blue whales. Among birds, scientists consider parrots, owls and corvids (crows and ravens) the brightest. Such a pecking order argues against the idea that intelligence evolved along a single path, culminating in human acumen. Instead intellect seems to have emerged independently in birds and mammals and also in cetaceans and primates.

Heavy Thoughts?
What about the brain might underlie these parallel paths to astuteness? One candidate is absolute brain size. Although many studies have linked brain mass with variations in human intelligence, size does not always correlate with smarts in different species. For example, clever small animals such as parrots, ravens, rats and relatively diminutive apes have brains of modest proportions, whereas some large animals such as horses and cows with large brains are comparatively dim-witted. Brain bulk cannot account for human intelligence either: At eight to nine kilograms, sperm and killer whale brains far outweigh the 1.4 kilograms of neural tissue inside our heads. As heavy as five kilograms, elephant brains are also much chunkier than ours.

Relative brain size—the ratio of brain to body mass—does not provide a satisfying explanation for interspecies differences in smarts either. Humans do compare favorably with many medium and large species: our brain makes up approximately 2 percent of our body weight, whereas the blue whale’s brain, for instance, is less than one 100th of a percent of its weight. But some tiny, not terribly bright animals such as shrews and squirrels win out in this measure. In general, small animals boast relatively large brains, and large animals harbor relatively small ones. Although absolute brain mass increases with body weight, brain mass as a proportion of body mass tends to decrease with rising body weight.

Another cerebral yardstick that scientists have tried to tie to intelligence is the degree of encephalization, measured by the encephalization quotient (EQ). The EQ expresses the extent to which a species’ relative brain weight deviates from the average in its animal class, say, mammal, bird or amphibian. Here the human brain tops the list: it is seven to eight times larger than would be expected for a mammal of its weight. But EQ does not parallel intellect perfectly either: gibbons and some capuchin monkeys have higher EQs than the more intelligent chimpanzees do, and even a few pro­sim­ians—the earliest evolved primates alive today—have higher EQs than gorillas do.

Or perhaps the size of the brain’s outermost layer, the cerebral cortex—the seat of many of our cognitive capacities—is the key. But it turns out that the dimensions of the cerebral cortex depend on those of the entire brain and that the size of the cortex constitutes no better arbiter of a superior mind. The same is true for the prefrontal cortex, the hub of reason and action planning. Although some brain researchers have claimed in the past that the human prefrontal cortex is exceptionally large, recent studies have shown that it is not. The size of this structure in hu­mans is comparable to its size in other ­primates and may even be relatively small as compared with its counterpart in elephants and cetaceans.

The lack of a large-scale measure of the human brain that could explain our performance may reflect the idea that human intellect may not be totally inimitable. Apes, after all, understand cause and effect, make and use tools, produce and comprehend language, and lie to and imitate others. These primates may even possess a theory of mind—the ability to understand another animal’s mental state and use it to guide their own behavior. Whales, dolphins and even some birds boast some of these mental talents as well. Thus, adult humans may simply be more intuitive and facile with tools and language than other species are, as opposed to possessing unique cognitive skills.

Networking
Fittingly, researchers have found the best correlates for intelligence by looking at a much smaller scale. Brains consist of nerve cells, or neurons, and supporting cells called glia. The more neurons, the more extensive and more productive the neuronal networks can be—and those networks determine varied brain functions, including perception, memory, planning and thinking. Large brains do not automatically have more neurons in fact, neuronal density generally decreases with increasing brain size because of the additional glial cells and blood vessels needed to support a big brain.

Humans have 11.5 billion cortical neurons—more than any other mammal, because of the human brain’s high neuronal density. Humans have only about half a billion more cortical neurons than whales and elephants do, however—not enough to account for the significant cognitive differences between humans and these species. In addition, however, a brain’s information-processing capacity depends on how fast its nerves conduct electrical impulses. The most rapidly conducting nerves are swathed in sheaths of insulation called myelin. The thicker a nerve’s myelin sheath, the faster the neural impulses travel along that nerve. The myelinated nerves in the brains of whales and elephants are demonstrably thinner than they are in primates, suggesting that information travels faster in the human brain than it does in the brains of nonprimates.

What is more, neuronal messages must travel longer distances in the relatively large brains of elephants and whales than they do in the more compact human brain. The resulting boost in information-processing speed may at least partly explain the disparity in aptitude between humans and other big-brained creatures.

Among humans’ cerebral advantages, language may be the most obvious. Various animals can convey complex messages to other members of their species they can communicate about objects that are not in sight and relay information about individuals and events. Chimpanzees, gorillas, dolphins and parrots can even understand and use human speech, gestures or symbols in constructions of up to about three words. But even after years of training, none of these creatures develops verbal skills more advanced than those of a three-year-old child.

In humans, grammar and vocabulary all but explode at age three. This timing corresponds with the development of Broca’s speech area in the left frontal lobe, which may be unique to humans. That is, scientists are unsure whether a direct precursor to this speech region exists in the nonhuman primate brain. The absence of an intricately wired language region in the brains of other species may explain why, of all animals, humans alone have a language that contains complex grammar. Researchers date the development of human grammar and syntax to between 80,000 and 100,000 years ago, which makes it a relatively recent evolutionary advance. It was also one that probably greatly enhanced human intellect.


Land Animals With The Best Memory

Again we need to look at animals with a long lifespan in order to find the terrestrial animals with the best memory.

Elephants

Elephants are really nice and loyal animals who take care of each other.

Scientists have found that elephants keep a map of all the water holes in their area. They always know where to go to get water for the little ones.

This shows a very good memory among adult elephants.

Most dog owners will let you know how good memories their dog has.

This is also why we can train dogs to learn a lot of tricks and to behave well.

Dogs wouldn’t be good service dogs and able to assist police officers if they weren’t able to remember a whole bunch of stuff. They can also recognize their owners after a very long time.

There are numerous examples of dogs who have found their way home after being away for a long time. This takes good memory skills and dogs are certainly among the most intelligent creatures in the animal kingdom.

Monkeys

Monkeys are very intelligent.

Apes and monkeys have very good memories. They are able to perform complicated tasks and they can remember what they learn.

They are probably this species we humans have done the most memory testing on.

They have been known to remember forms and signs and be able to sort puzzles and sort things. This shows us that apes and monkeys have at least some photographic memory. They can also be taught a long list of hand gestures and signs in order to communicate with humans.

The Rhesus monkeys have shown an amazing ability to be able to learn from past experiences. They will remember what happened last time that did the same thing.


This is How You Study The Evolution of Animal Intelligence

There are many scientists who study the mental abilities of animals. As intelligent animals ourselves, we’re keen to learn whether other species share our skills, and how our vaunted smarts evolved. We see study after study about whether chimpanzees care about fairness, whether pigeons outsmart humans at a classic maths problem, whether cuttlefish can remember where, what and when, or whether (and how) parrots and crows use tools,

But animals are hard to work with. You need to design tests that objectively assess their mental skills without raising the spectre of anthropomorphism, and you need to carefully train them to perform those tests. These difficulties mean that researchers mostly resort to small experiments with just one species, often with their own bespoke tasks. This makes it very hard to compare species or pool the results of separate studies. If a lemur behaves differently to a monkey in separate experiments, is it because of some genuine biological difference, or some quirk of the respective studies?

These problems mean that the study of animal intelligence is rich but piecemeal. Each study adds a new piece to the jigsaw, but is everyone even solving the same puzzle?

Evan MacLean, Brian Hare, and Charles Nunn from Duke University have had enough. They led a international team of 58 scientists from 25 institutes in studying the evolution of one mental skill—self-control—in 567 animals from 36 species.

Chimpanzees, gorillas, baboons, marmosets, lemurs, squirrels, dogs, elephants, pigeons, parrots and more tried their hands (or trunks or beaks or snouts) at the same two tasks. “It was literally a mouse-to-elephant study,” says MacLean, “or at least a Mongolian-gerbil-to-elephant study.”

“I think it’s really showing the future of the field of cognition,” says Karin Isler from the Universtiy of Zurich. “Instead of just giving glimpses and suggestions, and sometimes contradicting evidence, one can find convincing explanations for the evolution of cognitive abilities.”

The team focused on self-control—the ability to stop doing that, put that down, eat that later. Animals exercise it when they stop themselves from mating in the presence of a dominant peer, when they forgo an existing source of food in favour of foraging somewhere new, or when they share resources with their fellows. In humans, a child’s degree of self-control correlates with their health, wealth, and mental state as adults. It’s important.

It’s also easy to measure. Swiss psychologist Jean Piaget did it in the 1950s when he repeatedly put a toy under a box in front of some infants, and then moved it to a second box. He found that babies under 10 months of age would keep on searching under Box A, despite what they had seen. They couldn’t resist their old habit to do something flexible and different that ability only kicks in around our first birthday. MacLean, Hare and Nunn’s team gave this “A-not-B” test to their animals, using food rather than a toy.

They also tried a second task, where animals had to reach round the side of an opaque cylinder to get at food within. The team then swapped the opaque cylinder for a transparent one. Now, the animals had to hold back their natural instinct to reach directly for the food (which would have knocked the cylinder over), and go around as before.

The team tested all their animals on one or both tasks, and compared their performance to traits like brain size or group size. They found a few surprises. For example, the animals’ scores correlated with the absolute but not relative sizes of their brains. In other words, it didn’t matter whether the animals’ brains were big for their size, but whether they were big, full-stop.

“That’s funny because brain size and body size scale predictably. Big animals have big brains,” says MacLean. As such, many scientists believed that relative brain size mattered more. There’s even a measure called the encephalization quotient (EQ) that estimates intelligence by comparing an animal’s brain to that of a typical creature of the same size. And yet, for self-control at least, it’s absolute size that’s important. That was true whether they looked at all their 36 species, or just at the primates.

“That makes sense,” says Richard Byrne at the University of St Andrews. “If the brain is, to some extent, an on-board computer, it will be the number of components that determine its power [rather than] the size of the carrying case or body.”

The team also tested two leading explanations for the evolution of primate intelligence. One idea says that our smarts evolved so we could keep track of the relationships within our complex social groups. Indeed, you can make a decent guess about the size of community that a primate lives in by measuring the size of its skull. But the team found no link between group size and performance in their tasks. “That surprised us,” says MacLean. “It’s such a popular hypothesis but we found no evidence for it.”

Instead, the team found more support for a second idea: that primate intelligence was driven by the need to keep track of a wide range of food like fruit, which vary by place and season. They showed that the variety in the animals’ diets (but not the proportion of fruit) was indeed linked to self-control. Together, these two factors—absolute brain size and dietary breadth—explained around 82 percent of the variations in the primates’ scores.

“The nice thing about the tasks is that, because of their simplicity, they are very unlikely to depend a lot on species-specific aptitudes unrelated to cognition or to prior experience,” says Byrne. “I’d trust the results.”

But Robin Dunbar from the University of Oxford felt that the team’s conclusions are “misguided and naive” because their tasks weren’t a good measure of self-control, at least in any sense that matters in an animal’s social life. Instead they were “straight ecological or foraging tasks and nothing more, so it’s not awfully surprising that it correlates with diet,” he says.

Brain-scanning studies in humans and monkeys have also found links between the size of specific brain regions, size of social groups, and social skills. “It seems bizarre to be running an analysis against measures of total brain size,” says Dunbar.

Of course, this study just looked at one aspect of animal psychology, among many. The team found that the animals’ scores on the self-control tests did correlate with reports of other skills, like innovation, tool use, deception, and social learning. But MacLean suspects that if other teams focused on these skills, they would find different results. Group size may become more important if researchers focused on tasks that looked at social learning—the ability to imitate and learn from others. Alternatively, diet may again win out if scientists looked at memory skills.

This new study doesn’t settle the debates. It just points to a way forward. Each of the scientists in the team could easily have published their own papers using the collected data, but they decided to combine their efforts into one publication. “We thought it would be most powerful if it came out together,” says MacLean. “There’s never been a data set this size. We’re certainly hoping that it’s a game-changer in the way we do comparative psychology.”

And even Dunbar says, “It’s good to see comparative studies of this kind being done at last, and it’s very worthy that they have done the same task on many species.”


What if the filter is ahead of us?

These possibilities assume that the Great Filter is behind us—that humanity is a lucky species that overcame a hurdle almost all other life fails to pass. This might not be the case, however life might evolve to our level all the time but get wiped out by some unknowable catastrophe. Discovering nuclear power is a likely event for any advanced society, but it also has the potential to destroy such a society. Utilizing a planet's resources to build an advanced civilization also destroys the planet: the current process of climate change serves as an example. Or, it could be something entirely unknown, a major threat that we can't see and won't see until it's too late.

The bleak, counterintuitive suggestion of the Great Filter is that it would be a bad sign for humanity to find alien life, especially alien life with a degree of technological advancement similar to our own. If our galaxy is truly empty and dead, it becomes more likely that we've already passed through the Great Filter. The galaxy could be empty because all other life failed some challenge that humanity passed.

If we find another alien civilization, but not a cosmos teeming with a variety of alien civilizations, the implication is that the Great Filter lies ahead of us. The galaxy should be full of life, but it is not one other instance of life would suggest that the many other civilizations that should be there were wiped out by some catastrophe that we and our alien counterparts have yet to face.

Fortunately, we haven't found any life. Although it might be lonely, it means humanity's chances at long-term survival are a bit higher than otherwise.



Comments:

  1. Emanuel

    Unmatched message, I like it :)

  2. Shakticage

    I congratulate, your thought is simply excellent

  3. Domenick

    In my opinion it is obvious. You did not try to look in google.com?

  4. Kelmaran

    I was very interested in the material. What is the source? I would also read about this material

  5. Yozshukinos

    Do not despair! Funnier!

  6. Nicol

    I know they will help you find the right solution here.



Write a message