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In Brief
- Despite cartoons you may have seen showing a straight line of fish emerging on land to become primates and then humans, evolution is not so linear. The brains of other animals are not merely previous stages that led directly to human intelligence.
- Instead—as is the case with many traits—complex brains and sophisticated cognition have arisen multiple times in independent lineages of animals during the earth’s evolutionary history.
- With this new understanding comes a new appreciation for intelligence in its many forms. So-called lower animals, such as fish, reptiles and birds, display a startling array of cognitive capabilities. Goldfish, for instance, have shown they can negotiate watery mazes similar to the way rats do in intelligence tests in the lab.
We were talking about politics. My housemate, an English professor, opined that certain politicians were thinking with their reptilian brains when they threatened military action against Iran. Many people believe that a component of the human brain inherited from reptilian ancestors is responsible for our species’ aggression, ritual behaviors and territoriality.
One of the most common misconceptions about brain evolution is that it represents a linear process culminating in the amazing cognitive powers of humans, with the brains of other modern species representing previous stages. Such ideas have even influenced the thinking of neuroscientists and psychologists who compare the brains of different species used in biomedical research. Over the past 30 years, however, research in comparative neuroanatomy clearly has shown that complex brains—and sophisticated cognition—have evolved from simpler brains multiple times independently in separate lineages, or evolutionarily related groups: in mollusks such as octopuses, squid and cuttlefish; in bony fishes such as goldfish and, separately again, in cartilaginous fishes such as sharks and manta rays; and in reptiles and birds. Nonmammals have demonstrated advanced abilities such as learning by copying the behavior of others, finding their way in complicated spatial environments, manufacturing and using tools, and even conducting mental time travel (remembering specific past episodes or anticipating unique future events). Collectively, these findings are helping scientists to understand how intelligence can arise—and to appreciate the many forms it can take.
This article was originally published with the title One World, Many Minds.
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32 Comments
Add CommentI think the article was well written and investigated. It not only shows that we as humans have to view animals differently, but it shows the very detailed oriented thought processes of those doing the investigation. It makes me say 'wow!', their are some really brillant minds in existence, as well as makes me continue to cheer on the evolving human family. Thank you for a masterful document. Jurry Taalib-Deen
Reply | Report Abuse | Link to thisI really enjoyed this article. People tend to anthropomorphize everything around them. In the case of animals, it seems people are attributing exact human emotions to their domestic pets while denying any semblance of emotion or intelligence to other species. It's really puzzling to me. We're limited to using our own psyches as a comparison to the rest of the world. I'm thoroughly convinced that we understand our own minds very little, and those of other creatures with greatly less clarity. We are as different mentally from other creatures as we are physically.
Reply | Report Abuse | Link to thisFor those who enjoyed this article, I recommend reading some Temple Grandin. It's all speculation, but it's insightful stuff.
This whole subject would be much simpler to discuss if Science had an exact definition of the term intelligence. And this being the case, where can be the definition of 'Iintelligent Design' for creationists?
Reply | Report Abuse | Link to thisDeath to encephalisation quotients!
Reply | Report Abuse | Link to thisI see that the author refers to that much used metric of brain size in proportion to body size, without justifying its relevance. In fact I have never seen anywhere a justification for the meaningfulness of this ratio.
Reply | Report Abuse | Link to this@arjay-tea
Reply | Report Abuse | Link to thisThe ratio between body size and brain size is useful due to the fact that a larger body requires more neural infrastructure to run due to more motor and sensory paths that must be maintained. Thus, with an absolute floor on the size of the necessary brain needed to run the "machine"...what's left is available for higher cognitive functions. While perhaps a direct linear comparison between phylums (or even species) of brain/body mass ratios is unable to show an exact relationship of potential intelligence..it does give us a very rough starting point for predicting the overall potential based on the number of neurons available for things other than housekeeping. Just as a transistor count is a poor indicator, used in a vacuum, of microprocessor performance in particular benchmarks...one *can* use such metrics to predict overall performance classes from one family to the next. You might not be able to peg the frames per second a 100 million transistor cpu will yield in some particular game benchmark..but you could probably accurately predict that the 100 million transistor cpu will perform several magnitudes better than a 10,000 transistor cpu. Special-purpose processors can perform *much* better than a general purpose cpu with a given transistor count...which is potentially like comparing brains between phylums. However...even a specialized architecture is unlikely to overcome a 1000x (or more) difference in raw transistor power...and likewise a brain from one phylum that has a 1:10000 brain/body mass ratio is unlikely to overcome the difference between a 1:100 brain/body mass ratio in cognitive functions no matter what kind of specialized functionality that might have evolved for efficiency in a bang-for-neurons point of view.
My wife has exhibited occasional signs that she associates words with abstract concepts. Is this just some sort of training or am I anthropomorphizing? It'd be really freaky if I thought she could really understand what I waas saying to her.
Reply | Report Abuse | Link to thisit is luxury to read this kind of wide scope paper
Reply | Report Abuse | Link to thisWith apologies to Rene Descartes, "Sum ergo cognito" might well be the motto of neuroscience henceforth. Let's hope so, anyway, as we humanoids put ourselves into PROPER perspective as but one among many rather than regarding ourselves erroneously as "the paragon of animals."
Reply | Report Abuse | Link to thisWith apologies to Rene Descartes, "Sum ergo cognito" might well be the motto of neuroscience henceforth. Let's hope so, anyway, as we humanoids put ourselves into PROPER perspective as but one among many rather than as regarding ourselves erroneously as "the paragon of animals."
Reply | Report Abuse | Link to this"we know that some emotional systems subsequently evolved to promote the pair bonding that is ubiquitous among human cultures but absent in our closest primate relatives."
Reply | Report Abuse | Link to thisI'm surprised that SciAm would print an article with such a blatant error. Pygmy chimps or bonobos are well known for their sexual behaviour that goes beyond mere reproduction or as a method of stress relief. Pair bonding between all members in a community is strengthened through sex, the sole exception being mothers and their own sons over six years old.
Someone hasn't done their research!
In spite of all the new discoveries about the behavioral capabilities of various sub-human animals, in terms of our psychic level, a term coined by Lloyd C. Morgan (of Morgan's Canon fame), to designate the qualitative complexity of behavior (or of neural integration), we, humans alone, still are the "crown of evolution"!
Reply | Report Abuse | Link to thisAnyone who questions that is just being silly.
To fully realise how preposterously silly it is, just try to imagine the day when Scientific American will hire an octopus, a parrot, or a chimp, to join its roster of editors
In spite of all the new discoveries about the behavioral capabilities of various sub-human animals, in terms of psychic level, a term coined by Lloyd C. Morgan (of Morgan;s Canon fame), to designate qualitative complexity of behavior (or of neural integration), we, humans alone, are still "the crown of evolution"!
Reply | Report Abuse | Link to thisAnyone who questions this is just being silly.
To fully realise how silly, just try to imagine the day when Scientific American will hire an octopus, a parrot, or a chimp, to join its editorial board.
Ruth Rosin - You species biggot!!!
Reply | Report Abuse | Link to thisW00T!! Go my squidish kin! We am smartziz!
Intellegence is also related to density of brain mass as well as brain to body ratio.
I would like to see tests of the various animals to see which can learn from observing other species. I would also like to see if tools made for ease of use by these various species would be adopted by individual animals to improve their survival and prosperity over tools they made themselves.
Indeed, I wonder if some of these creatures could be taught to create and read symbols to indicate issues that would be of use to them. Something like a squiggly line indicating that worms may found in the ground at a specific spot. Perhaps an arrow that indicates the direction to turn a lid for an octopus to open a jar.
I would also like to know if anyone is looking into breeding programs to increase the "available brain mass" of some of these creatures. I'm not sure how I feel about evolved cephalopods or other altered critters. The more we learn about brain development and genetics the more likely that someone will want to usurp God's role and make altered animals. While that could be really cool, it also is really kind of creepy and potentially disasterous on a global scale.
I have raised chickens for a number of years and have observed their behavior as well. They have good memories. They can learn and they definately are not stupid as we may think. >Mike a.
Reply | Report Abuse | Link to thisI have raised chickens and have observed their behavior for many years. Like most birds they can learn and have great memories. I can see a lot of similatities in what i have observed and what was described in this artical. I wonder if a study has been on the inteligence of domesticated animals?But then that might spoil our appitite for chicken nuggets.
Reply | Report Abuse | Link to thisThanks for this reply to the body-size intelligence conundrum - it's been bothering me for years. I have tended to assume that it was sheer vanity that made hmans so fond of this index. I do still question however whether humans are quite as bright as they like to think. They did after all exist for a very long time (perhaps a million years) whithout showing much sign of superiority Only in the last 5000 years have we begun to show special powers - and even then it is only a rather small scientific elite that makes a significant contribution. The average human has little grasp of science and would be unable on his own to recreate the technology that we regard as the hallmark of our dominant position on earth. In other words, our seeming supremacy seems to be due more to our ability to pass things on through language than to raw thinking power.
Reply | Report Abuse | Link to thisThe trait that separates humans from other animals is their powerful human imagination. Humans have two imaginations; the learning imagination and the creative imagination. Animals have learning imaginations but they have very little creative imagination. Ever since humans evolved their creative imagination around 50 thousand years ago they began to progress. Before that, they made little or no progress. The other animals though they are intelligent enough for their survival do not progress. That is the difference - modern humans are an imaginative species - the "Homo Imaginative Sapiens".
Reply | Report Abuse | Link to thisEvery facet of human progress is a result of its powerful human imagination.
http://novan.com/pwr-imag.htm (Mankind' Two Imaginations)
http://novan.com/articles.htm Articles about human imagination and other topics.
The big difference between modern humans and other animals is that modern humans progress while the other animals do not. Modern humans have two very powerful imaginations; the learning imagination and the creative imagination while the other animals have a learning imagination but very little creative imagination. Every facet of human progress is a result of both of these imaginations working together. For more on this subject see:
Reply | Report Abuse | Link to thishttp://novan.com/pwr-imag.htm (Mankind's two Imaginations)
http://novan.com/articles.htm More articles on this and other subjects.
The big difference between modern humans and other animals is that modern humans progress while the other animals do not. Modern humans have two very powerful imaginations; the learning imagination and the creative imagination while the other animals have a learning imagination but very little creative imagination. Every facet of human progress is a result of both of these imaginations working together. For more on this subject see:
Reply | Report Abuse | Link to thishttp://novan.com/pwr-imag.htm (Mankind's two Imaginations)
http://novan.com/articles.htm More articles on this and other subjects.
I am a bit disappointed that such well researched paper ignores what the fundamental difference between humans and subhuman species. Any ethologist will tell you about the superiority in sensory resolution many species are genetically endowed with. Likewise for the sophistication and complexity of motor responses. It is clear that we cannot compete with subhumans at the spinal, supraspinal and subcortical levels of reflex integration committed to safeguard the biological integrity of the species. When we move from the stereotypic, genetic coding of awareness <--> response scripts to the individualized memetic coding of probable solutions extending the biological survival to the psychosocial realm then we start seeing differences. Like subhuman species, we spend a long time of our vigil state in constant evaluation and updating of the environmental sensory input watching for the detection of significant alterations in the input that pose a potential life threat and may require the elaboration of adaptive responses. The real difference comes when the species is confronted with novel contingencies of unknown content. Subhuman species will have accessed all its stereotyped inherited or acquired resources, including context analysis using memory coded data bases. Unfortunately our subhuman friends lack the ability to summon the participation of higher cortical levels for the processing symbolic or sentential representations of the novel contingency in the inferential elaboration of syllogistic premises/conclusions and solutions to the ensuing potential threat.. With the resulting linear processing of environmental inputs at this higher level inner language and thought are concomittantly co-generated where actor and observer emerge, something a subhuman species cannot do. Our difference with animals is a qualitative one. More on this at: http://delaSierra-Sheffer.net , Vol. I, II Neurophilosophy of Consciousness. Dr.d
Reply | Report Abuse | Link to thisspecies appropriate tests of cognition, Yes.
Reply | Report Abuse | Link to thisLet's have them right away and quit all this conflict.
A good one would be how to say Hi.
are humans the only intelligent life that evovled on this planet ?
Reply | Report Abuse | Link to thisThe brain of every animal including man has evolved so that it contains the highest degrees of intelligence in the areas needed to survive, live as well as possible and be content (happy). The many areas of thoughtful intelligence that other animals exhibit and that we don't understand we call "instinct".
Reply | Report Abuse | Link to thisThe brain of every animal including man has evolved so that it contains the highest degrees of intelligence in the areas needed to survive, live as well as possible and be content (happy). The many areas of thoughtful intelligence that other animals exhibit and that we don't understand we call "instinct".
Reply | Report Abuse | Link to thisIf the scientists in this article would only take the Bible as seriously as they do the studies and therories of their own cohorts, they'd already have the answer to this question. The answer is in the book of Genesis.
Reply | Report Abuse | Link to thisLiving things only seem to have "evolved" from other "earlier" living things because the maker of those living things re-used some of the same parts. The evolutionists think they have won the arguement when they point out that extinct creatures (and living ones that they consider to be less highly evolved) have certain things in common with currently living creatures. What they don't realize is that this is actually an arguement for intelligent design. Why would God make every living thing totally different from every other living thing? Living things need to be closely related in many ways for several reasons. One of them is compatibility. Animals (and certain plants) that live by eating other animals and plants would not be able to digest them if the food they ate was totally alien to their own body. Don't believe me? Try eating a piece of aluminum foil sometime and let me know how well you digest it.
Reply | Report Abuse | Link to thisSimilar designs in living things point to there being the same designer. Just like you can tell that the Ford Focus and the VW Beetle were designed by the same team by looking at their similarites, you can tell that a man and a monkey were designed by the same guy too.
The platypus proves that God has a sense of humour.
When God created the universe He created everything, past, present & future so that it and everything in it would develope and evolve perfectly. You see God every day or you don't see him at all.
Reply | Report Abuse | Link to thisAmen!
Reply | Report Abuse | Link to thisIn God's image man and woman are created. I thinks that sums up that mankind is in a "higher" class in and of itself. Everything was good and created for man's benefit.
Reply | Report Abuse | Link to thisgod a concept so overriding that lead to absurd conclusions .. to sum it up .. it is not god that created man .. but man created god .. in its own image ..
Reply | Report Abuse | Link to thisconsciousness .. its origin .. its makeup .. its rise .. to be found .. amidst the complexity .. of life overwhelming our planet
Reply | Report Abuse | Link to thisconsciousness .. not to be looked at or upon the premise as being .. a privilege bestowed upon the human kind .. but consciousness as a universal property of all living things