In NOT A CHIMP I begin to construct a bio-social model for human domestication based on several variants of common - and crucial - neurotransmitters: vasopressin, dopamine, MAO and serotonin. Research from Oregon State University and UC Berkeley can now add oxytocin to the pile. Individuals having a particular genetic variant of the oxytocin receptor performed much better on the "Reading The Mind In The Eyes" test than individuals with a form of the receptor often noticed in people with autism. This Sciencenow article concludes:
The work is "one solid step forward" in understanding the role of oxytocin in human social behavior, says neuroeconomist Paul Zak of the Claremont Graduate University in Claremont, California, who has studied the effects of oxytocin on economic decisions. "This is a really nice example where the variation [in social behavior] that we see in animals can now be traced back and even seen in people," adds neuroscientist Larry Young of Emory University in Atlanta. But because polymorphism studies sometimes can't be replicated, Young remains cautious about the results until they can be repeated in a larger group.
NOT A CHIMP
Click on the cover to link to OUP's e-catalogue then turn to the biology section.
Interview Podcast with George Miller
Click on the pic to link to the NOT A CHIMP podcast on Blackwell's Website
Monday, 23 November 2009
Sunday, 22 November 2009
Open Letters Review For "Not A Chimp"
Excellent review for the book by Tuc McFarland in 'Open Letters".
Microreview: Not a Chimp
Not A Chimp: The Hunt
To Find The Genes That Make Us Human
By Jeremy Taylor
Oxford University Press, 2009
When Jeremy Taylor writes, in his terrific, rabble-rousing book Not a Chimp, that “we humans are an exceptional species,” he’s courting trouble from all comers, and you get the sense that he not only knows that but delights in it. Animal rights activists and many animal behaviorists will say he’s wrong: humans share, we’re so often told, 98% of our genetic makeup with chimpanzees, after all – surely the rest is window-dressing? Surely any attempt to reposition mankind at the unique and undisputed top of the evolutionary ladder is an attempt to sanction all the barbarities mankind has perpetrated on so-called “lesser” animals, most certainly including chimps, throughout history?
Taylor is having none of this. He makes the point – and follows it with a very detailed, very convincing layman’s tour of the neuroscience involved – that when it comes to evolution and life sciences, tiny percentage points can make gigantic differences. He urges his readers to move past a “chimp-ist” viewpoint in which taxonomical proximity to mankind lends chimps a brighter aura of sentience than, say, ravens or goats or elephants:
The important take-home point is that cognition is a tool to do an adaptive job, and when social and ecological problems are similar it can be expected to solve them in similar fashion, whatever the species. Claims for chimpanzee tool use, deception, manipulation of others, and insight can no longer reinforce claims for their evolutionary and genetic proximity to us, but only show that, like big-brained corvids, they have shared some of the same social and ecological problems as us. Any species that does so will evolve the necessary, and functionally analogous, cognitive structures to deal with them. The argument by analogy is undone.
Not a Chimp is a merry counter-blast to the animal rights and conservation activists who advocate, at least partly on the basis of genetics, extending human rights to mankind’s nearest cousins. The book’s flaw is tribal: Taylor stresses the cognitive differences between humans and chimps in order to pull back human-style civil rights, to stop the “lunacy” of extending those rights to chimpanzees. The fascinating science he’s synthesized and shared would work equally well if his ethics were more elastic – not fewer rights for chimps, but more rights for everybody, including, say, ravens, goats, and elephants.
–Tuc McFarland
Microreview: Not a Chimp
Not A Chimp: The Hunt
To Find The Genes That Make Us Human
By Jeremy Taylor
Oxford University Press, 2009
When Jeremy Taylor writes, in his terrific, rabble-rousing book Not a Chimp, that “we humans are an exceptional species,” he’s courting trouble from all comers, and you get the sense that he not only knows that but delights in it. Animal rights activists and many animal behaviorists will say he’s wrong: humans share, we’re so often told, 98% of our genetic makeup with chimpanzees, after all – surely the rest is window-dressing? Surely any attempt to reposition mankind at the unique and undisputed top of the evolutionary ladder is an attempt to sanction all the barbarities mankind has perpetrated on so-called “lesser” animals, most certainly including chimps, throughout history?
Taylor is having none of this. He makes the point – and follows it with a very detailed, very convincing layman’s tour of the neuroscience involved – that when it comes to evolution and life sciences, tiny percentage points can make gigantic differences. He urges his readers to move past a “chimp-ist” viewpoint in which taxonomical proximity to mankind lends chimps a brighter aura of sentience than, say, ravens or goats or elephants:
The important take-home point is that cognition is a tool to do an adaptive job, and when social and ecological problems are similar it can be expected to solve them in similar fashion, whatever the species. Claims for chimpanzee tool use, deception, manipulation of others, and insight can no longer reinforce claims for their evolutionary and genetic proximity to us, but only show that, like big-brained corvids, they have shared some of the same social and ecological problems as us. Any species that does so will evolve the necessary, and functionally analogous, cognitive structures to deal with them. The argument by analogy is undone.
Not a Chimp is a merry counter-blast to the animal rights and conservation activists who advocate, at least partly on the basis of genetics, extending human rights to mankind’s nearest cousins. The book’s flaw is tribal: Taylor stresses the cognitive differences between humans and chimps in order to pull back human-style civil rights, to stop the “lunacy” of extending those rights to chimpanzees. The fascinating science he’s synthesized and shared would work equally well if his ethics were more elastic – not fewer rights for chimps, but more rights for everybody, including, say, ravens, goats, and elephants.
–Tuc McFarland
Thursday, 19 November 2009
The Absent Referent
In NOT A CHIMP I devote a great deal of time discussing whether or not chimps, or any other animal species for that matter, can have any understanding of entities that are invisible - like mental states in the brains of other individuals and physical forces in the natural world - like gravity. I conclude that there is still no reliable evidence that chimps can mind read or have any grasp of "folk" or intuitive physics. Here, in an evol-psych group essay, editor Robert Karl Stonjek adds a third invisible to the array of cognitive powers we humans have and chimps don't - the absent referrant.
The Absent Referent
Robert Karl Stonjek
* * * * Black marks on the asphalt. A child's toy lays broken. * * * *
In their recent paper "Prelinguistic Infants, but Not Chimpanzees, Communicate About Absent Entities", Ulf Liszkowski, Marie Schäfer, Malinda Carpenter, and Michael Tomasello point out that chimps are unable to communicate information about the absent referent.
An experimenter places a favoured object away from baby/chimp subjects. Both are capable of gesturing their desire for the object. Then the object is placed behind a screen. Again, chimp and human subjects can gesture their interest in the object behind the screen.
Now the object is placed in a 'usual' location a few times, so that ape and human become familiar with the usual location of the object. And then the object is removed altogether (the location is now a referent for the absent object). The baby, but not the chimp, will gesture toward the absent referent and try to draw the attention of the experimenter to the missing object.
I speculate that infant chimps may also understand the absent referent but that adult chimps (as in this experiment) will not. I note that some dogs and cats will gesture toward their empty bowls when water or food is absent (my cat will do this when the bowl is running low and it wants the bowl placed outside the door for the night.)
But the absent referent is much more than this in humans. The absent referent acquires a property attributable to the referent that is absent. The imagery at the head of this essay conjures an image of a child hit by a motor car, even though there is no evidence of such an event. The lost wedding ring that is replaced by a new one is not the same because of the absent referent. 'Qualia' can be thought of as the referent which is absent (properties implied by the target object).
Humans not only see or have knowledge of the referent which is absent, they perceive its vestige as a property of the thing from which it is absent. We say that grandpa's walking stick reminds us of him, but we also perceive something of grandpa in the walking stick which is why we want to keep it. If it were just a reminder then a replica would be sufficient.
Tools may be a simple as a particularly shaped stone. But the stone tool takes on a special character when the ability to perceive the absent referent has evolved. The use of the tool remains with that tool, we see it (the absent referent). If we gained status at the time of using the tool, then that status remains with the tool as an additional absent referent. The tool takes on those qualities ~ status and utility ~ even though the tool is not being used. Thus humans readily kept tools and defended the possession of them in the same way they defend any other aspect of their status.
Words can be characterised as having a denotation (the bland dictionary meaning) and a connotation (the feeling the word evokes, its inner meaning or personal meaning to us). The connotation is the absent referent ~ the thing that the word refers to, even when the thing is not present. The feeling behind every word, that which gives the word meaning, can be traced back to the absent referent that the baby described above 'sees' when pointing to the place where the favoured object usually sits ~ the chimp does not 'see' it.
Not all words map directly onto concrete objects or actions. There is a long and complex cognitive road between the simplest absent referent and the full language we currently use. But the same root form gives rise to art, music, language, the concept of future and past, religion and all else that makes up human culture. Absent referents can be manipulated as abstract or symbolic forms.
As mentioned earlier, I think it is highly probable that the precursor of humans with language would have had absent referent capability as children and this would have been a necessary part of playing behaviour. When the ability to model the absent referent entered adulthood, probably due to a single gene mutation, we had the genesis of all that is uniquely human.
The Absent Referent
Robert Karl Stonjek
* * * * Black marks on the asphalt. A child's toy lays broken. * * * *
In their recent paper "Prelinguistic Infants, but Not Chimpanzees, Communicate About Absent Entities", Ulf Liszkowski, Marie Schäfer, Malinda Carpenter, and Michael Tomasello point out that chimps are unable to communicate information about the absent referent.
An experimenter places a favoured object away from baby/chimp subjects. Both are capable of gesturing their desire for the object. Then the object is placed behind a screen. Again, chimp and human subjects can gesture their interest in the object behind the screen.
Now the object is placed in a 'usual' location a few times, so that ape and human become familiar with the usual location of the object. And then the object is removed altogether (the location is now a referent for the absent object). The baby, but not the chimp, will gesture toward the absent referent and try to draw the attention of the experimenter to the missing object.
I speculate that infant chimps may also understand the absent referent but that adult chimps (as in this experiment) will not. I note that some dogs and cats will gesture toward their empty bowls when water or food is absent (my cat will do this when the bowl is running low and it wants the bowl placed outside the door for the night.)
But the absent referent is much more than this in humans. The absent referent acquires a property attributable to the referent that is absent. The imagery at the head of this essay conjures an image of a child hit by a motor car, even though there is no evidence of such an event. The lost wedding ring that is replaced by a new one is not the same because of the absent referent. 'Qualia' can be thought of as the referent which is absent (properties implied by the target object).
Humans not only see or have knowledge of the referent which is absent, they perceive its vestige as a property of the thing from which it is absent. We say that grandpa's walking stick reminds us of him, but we also perceive something of grandpa in the walking stick which is why we want to keep it. If it were just a reminder then a replica would be sufficient.
Tools may be a simple as a particularly shaped stone. But the stone tool takes on a special character when the ability to perceive the absent referent has evolved. The use of the tool remains with that tool, we see it (the absent referent). If we gained status at the time of using the tool, then that status remains with the tool as an additional absent referent. The tool takes on those qualities ~ status and utility ~ even though the tool is not being used. Thus humans readily kept tools and defended the possession of them in the same way they defend any other aspect of their status.
Words can be characterised as having a denotation (the bland dictionary meaning) and a connotation (the feeling the word evokes, its inner meaning or personal meaning to us). The connotation is the absent referent ~ the thing that the word refers to, even when the thing is not present. The feeling behind every word, that which gives the word meaning, can be traced back to the absent referent that the baby described above 'sees' when pointing to the place where the favoured object usually sits ~ the chimp does not 'see' it.
Not all words map directly onto concrete objects or actions. There is a long and complex cognitive road between the simplest absent referent and the full language we currently use. But the same root form gives rise to art, music, language, the concept of future and past, religion and all else that makes up human culture. Absent referents can be manipulated as abstract or symbolic forms.
As mentioned earlier, I think it is highly probable that the precursor of humans with language would have had absent referent capability as children and this would have been a necessary part of playing behaviour. When the ability to model the absent referent entered adulthood, probably due to a single gene mutation, we had the genesis of all that is uniquely human.
Symbolic Gestures And Spoken Language Are Processed By A Common Neural System
Excellent paper by a team which includes Pat Gannon. I cannot do better than to reproduce the abstract and for those of you more interested, and not able to source PNAS normally through a university library system, this is one of their open access articles - its free!
Abstract
Symbolic gestures, such as pantomimes that signify actions (e.g., threading a needle) or emblems that facilitate social transactions (e.g., finger to lips indicating “be quiet”), play an important role in human communication. They are autonomous, can fully take the place of words, and function as complete utterances in their own right. The relationship between these gestures and spoken language remains unclear. We used functional MRI to investigate whether these two forms of communication are processed by the same system in the human brain. Responses to symbolic gestures, to their spoken glosses (expressing the gestures' meaning in English), and to visually and acoustically matched control stimuli were compared in a randomized block design. General Linear Models (GLM) contrasts identified shared and unique activations and functional connectivity analyses delineated regional interactions associated with each condition. Results support a model in which bilateral modality-specific areas in superior and inferior temporal cortices extract salient features from vocal-auditory and gestural-visual stimuli respectively. However, both classes of stimuli activate a common, left-lateralized network of inferior frontal and posterior temporal regions in which symbolic gestures and spoken words may be mapped onto common, corresponding conceptual representations. We suggest that these anterior and posterior perisylvian areas, identified since the mid-19th century as the core of the brain's language system, are not in fact committed to language processing, but may function as a modality-independent semiotic system that plays a broader role in human communication, linking meaning with symbols whether these are words, gestures, images, sounds, or objects.
Abstract
Symbolic gestures, such as pantomimes that signify actions (e.g., threading a needle) or emblems that facilitate social transactions (e.g., finger to lips indicating “be quiet”), play an important role in human communication. They are autonomous, can fully take the place of words, and function as complete utterances in their own right. The relationship between these gestures and spoken language remains unclear. We used functional MRI to investigate whether these two forms of communication are processed by the same system in the human brain. Responses to symbolic gestures, to their spoken glosses (expressing the gestures' meaning in English), and to visually and acoustically matched control stimuli were compared in a randomized block design. General Linear Models (GLM) contrasts identified shared and unique activations and functional connectivity analyses delineated regional interactions associated with each condition. Results support a model in which bilateral modality-specific areas in superior and inferior temporal cortices extract salient features from vocal-auditory and gestural-visual stimuli respectively. However, both classes of stimuli activate a common, left-lateralized network of inferior frontal and posterior temporal regions in which symbolic gestures and spoken words may be mapped onto common, corresponding conceptual representations. We suggest that these anterior and posterior perisylvian areas, identified since the mid-19th century as the core of the brain's language system, are not in fact committed to language processing, but may function as a modality-independent semiotic system that plays a broader role in human communication, linking meaning with symbols whether these are words, gestures, images, sounds, or objects.
Wednesday, 18 November 2009
Right-Handed Chimps Provide Clues To The Origin Of Human Language
More good news for those scientists who support the idea that human language evolved from the use of intentional gestures. Bill Hopkins, and French colleagues, have been recording communicative gestures in chimps for years and have found a highly significant bias to use of the right hand in communicative gestures used in contexts like attention getting, shared excitation, threat, aggression, greeting, reconciliation, and overtures to play. This, of course, implies left lateralization of the brain for these gestures. As the scientists conclude: "This finding provides additional support to the idea that speech evolved initially from a gestural communication system in our ancestors. Moreover, gestural communication in apes shares some key features with human language, such as intentionality, referential properties and flexibility of learning and use."
Thursday, 12 November 2009
Fair Play In Humans, Monkeys And Apes
A really nice article, in New Scientist, by Frans De Waal, of the Yerkes Primate Centre, looking at the likely evolutionary roots of a sense of fair play in primates. The article kicks off like this:
HOW often have you seen rich people take to the streets, shouting that they're earning too much? No, I thought not. Protesters are typically blue-collar workers yelling that the minimum wage has to go up, or that their jobs shouldn't go overseas. Lately, however, we have been hearing a new chorus, exclaiming that none of those fat cats on Wall Street or the City should be compensated for bad behaviour. No golden parachutes for those greedy bloodsuckers!
Concern about fairness is always asymmetrical (stronger in the poor than the rich), and the underlying emotions aren't half as lofty as the ideal itself. It is true to say that our sense of fairness seldom transcends self-interest, that it is seldom concerned with something larger than ourselves. Look at how it starts in life. Children react to the slightest discrepancy in the size of their slice of pizza compared to their sibling's. Their shouts of "That's not fair!" never transcend their own desires.
We're all for fair play so long as it helps us. There's even a biblical parable about this, in which the owner of a vineyard rounded up labourers at different times of the day. Early in the morning, he went out to find labourers, offering each 1 denarius. But he offered the same to those hired later in the day. The workers hired first thing in the morning expected to get more since they had worked through the heat of the day, yet the owner didn't feel he owed them any more than he had originally promised.
That this sense of unfairness may turn out to be quite ancient in evolutionary terms as well became clear when graduate student Sarah Brosnan and I discovered it in monkeys. While testing pairs of capuchin monkeys, we noticed how much they disliked seeing their partner get a better deal. At first, this was just an impression based on their refusal to participate in our tests. But then we realised that economists had given these reactions the fancy label of "inequity aversion," which they had turned into a topic of academic debate. This debate revolved entirely around human behaviour, but what if monkeys showed the same aversion?.............
HOW often have you seen rich people take to the streets, shouting that they're earning too much? No, I thought not. Protesters are typically blue-collar workers yelling that the minimum wage has to go up, or that their jobs shouldn't go overseas. Lately, however, we have been hearing a new chorus, exclaiming that none of those fat cats on Wall Street or the City should be compensated for bad behaviour. No golden parachutes for those greedy bloodsuckers!
Concern about fairness is always asymmetrical (stronger in the poor than the rich), and the underlying emotions aren't half as lofty as the ideal itself. It is true to say that our sense of fairness seldom transcends self-interest, that it is seldom concerned with something larger than ourselves. Look at how it starts in life. Children react to the slightest discrepancy in the size of their slice of pizza compared to their sibling's. Their shouts of "That's not fair!" never transcend their own desires.
We're all for fair play so long as it helps us. There's even a biblical parable about this, in which the owner of a vineyard rounded up labourers at different times of the day. Early in the morning, he went out to find labourers, offering each 1 denarius. But he offered the same to those hired later in the day. The workers hired first thing in the morning expected to get more since they had worked through the heat of the day, yet the owner didn't feel he owed them any more than he had originally promised.
That this sense of unfairness may turn out to be quite ancient in evolutionary terms as well became clear when graduate student Sarah Brosnan and I discovered it in monkeys. While testing pairs of capuchin monkeys, we noticed how much they disliked seeing their partner get a better deal. At first, this was just an impression based on their refusal to participate in our tests. But then we realised that economists had given these reactions the fancy label of "inequity aversion," which they had turned into a topic of academic debate. This debate revolved entirely around human behaviour, but what if monkeys showed the same aversion?.............
Do Chimps Understand Beliefs?
The comparative cognitive psychology team at the Max Planck Institute in Leipzig continue to conjure up exciting and informative experiments to compare ape and human cognition. This reports on an experiment that has evolved from the competitive food-grabbing experiments designed by Brian Hare and reported on in the chapter POVINELLI'S GAUNTLET in the book. In that case a subordinate chimp and a dominant chimp faced doors into a common enclosure in which food was baited either in the open or behind obstacles in conditions where either or both animals could see the food baited. Would the subordinate chimp behave differently in its choice of which food to go for if the vision of the dominant chimp had been obscured by a shutter at the time the enclosure was baited? In other words, did the subordinate chimp have some idea of beliefs and knowledge in the head of the other chimp? Let cognitive daily pick up the story:
Juliane Kaminski, Josep Call, and Michael Tomasello set up a more complicated competitive situation for both chimps and human children. Two chimps sat in separate rooms with windows so they could see each other and a table between their rooms.
The table had a movable center with three inverted buckets, each capable of hiding a treat. Each chimp's view of the table could be blocked separately. For each task, the experimenter hid a piece of banana under one of the three buckets. In addition, each chimp had her own bucket which she knew contained a less appealing snack: a piece of apple. The children had a similar setup, except they played against an adult, and they weren't confined to chimp-proof rooms. The kids' appealing reward was a toy, and the less-appealing reward was a wooden block.
For the chimps, the game worked like this: While both chimps watched, the experimenter placed the banana under one of the buckets. Then the treat was either moved to a new bucket, or kept in the same place, while both chimps watched or while one had her view of the buckets blocked. Then the chimps got to pick which bucket they thought contained the treat. Only one of the two chimps was actually being tested, and the tested chimp always picked second--and she did not get to see her competitor making the choice. She always had the option of picking the guaranteed treat on the table next to her, or she could take a chance and go for the banana, a much more appealing treat.
There were four possible scenarios in each game: Both chimps saw the banana being moved or kept in the original bucket, or the chimp being studied saw the banana moved or kept in the original bucket while hidden from view of the competing chimp. How often did the chimps (and kids) try for the more appealing prize?
The 6-year-olds came closest to the optimal strategy. They generally didn't choose the better treat when the competitor saw the treat being moved (or not moved) from one bucket to another. Even though they didn't see the competitor choose a bucket, they guessed that the competitor would have already taken the treat, and therefore the best they could do would be to pick the guaranteed, lesser treat.
However, when the object had been moved from one bucket to another and the competitor didn't see the move, they picked the better treat more than 70 percent of the time, figuring that the competitor was unlikely to have guessed the correct location of the treat. When the treat was kept in the same location, even though the competitor didn't see what happened behind the occluder, they chose it less often, presumably because they figured that the competitor was most likely to believe that the treat was in the same spot it had been left in before.
Three-year-olds, by contrast, pretty much always chose the guaranteed lesser treat, presumably because they weren't sure what their competitor had done.
Chimps did somewhat better: they chose to go after the prefered treat significantly more often when they saw that their competitor hadn't seen it moved (or kept in the same place). However, their decision was the same whether or not the treat was actually moved. This suggests their understanding of their competitor's knowledge is not as sophisticated as a six-year-old's: they didn't behave differently when there was reason to believe that their competitor had a mistaken impression of where the treat was located.
Chimps, it seems, do have some idea what other chimps are thinking. They have less of an understanding of their competitors' mistaken beliefs.
Juliane Kaminski, Josep Call, and Michael Tomasello set up a more complicated competitive situation for both chimps and human children. Two chimps sat in separate rooms with windows so they could see each other and a table between their rooms.
The table had a movable center with three inverted buckets, each capable of hiding a treat. Each chimp's view of the table could be blocked separately. For each task, the experimenter hid a piece of banana under one of the three buckets. In addition, each chimp had her own bucket which she knew contained a less appealing snack: a piece of apple. The children had a similar setup, except they played against an adult, and they weren't confined to chimp-proof rooms. The kids' appealing reward was a toy, and the less-appealing reward was a wooden block.
For the chimps, the game worked like this: While both chimps watched, the experimenter placed the banana under one of the buckets. Then the treat was either moved to a new bucket, or kept in the same place, while both chimps watched or while one had her view of the buckets blocked. Then the chimps got to pick which bucket they thought contained the treat. Only one of the two chimps was actually being tested, and the tested chimp always picked second--and she did not get to see her competitor making the choice. She always had the option of picking the guaranteed treat on the table next to her, or she could take a chance and go for the banana, a much more appealing treat.
There were four possible scenarios in each game: Both chimps saw the banana being moved or kept in the original bucket, or the chimp being studied saw the banana moved or kept in the original bucket while hidden from view of the competing chimp. How often did the chimps (and kids) try for the more appealing prize?
The 6-year-olds came closest to the optimal strategy. They generally didn't choose the better treat when the competitor saw the treat being moved (or not moved) from one bucket to another. Even though they didn't see the competitor choose a bucket, they guessed that the competitor would have already taken the treat, and therefore the best they could do would be to pick the guaranteed, lesser treat.
However, when the object had been moved from one bucket to another and the competitor didn't see the move, they picked the better treat more than 70 percent of the time, figuring that the competitor was unlikely to have guessed the correct location of the treat. When the treat was kept in the same location, even though the competitor didn't see what happened behind the occluder, they chose it less often, presumably because they figured that the competitor was most likely to believe that the treat was in the same spot it had been left in before.
Three-year-olds, by contrast, pretty much always chose the guaranteed lesser treat, presumably because they weren't sure what their competitor had done.
Chimps did somewhat better: they chose to go after the prefered treat significantly more often when they saw that their competitor hadn't seen it moved (or kept in the same place). However, their decision was the same whether or not the treat was actually moved. This suggests their understanding of their competitor's knowledge is not as sophisticated as a six-year-old's: they didn't behave differently when there was reason to believe that their competitor had a mistaken impression of where the treat was located.
Chimps, it seems, do have some idea what other chimps are thinking. They have less of an understanding of their competitors' mistaken beliefs.
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