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?.............
Are we humans simply remodelled apes? Chimps with a tweak? Is the difference between our genomes so minuscule it justifies the argument that our cognition and behaviour must also differ from chimps by barely a whisker? If “chimps are us” should we grant them human rights? Or is this one of the biggest fallacies in the study of evolution? NOT A CHIMP argues that these similarities have been grossly over-exaggerated - we should keep chimps at arm’s length. Are humans cognitively unique after all?
Thursday, 12 November 2009
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.
FOXP2 Gene And Ramifying Roots Of Language
Here is news of a very important paper indeed. I've given the url for the Wired article as it is a clear and simple in-road, but there is also good info on the John Hawks weblog (see this blog's side-bar) and the source articles and commentary by Pasko Rakic are in this week's NATURE (vol. 462 pp. 213-217, and pp. 169-170). Lead authors are Genevieve Konopka and Dan Geschwind, of UCLA.
The work concerns the gene FOXP2 - star of chapter 2 in my book, THE LANGUAGE GENE THAT WASN'T. Most will recall that FOXP2 is at the root of an extraordinary speech AND language disorder in an extended London family, that it has accumulated two mutations inside the last 200,000 years (compared to the chimp), that it appears to have come under considerable selection pressure, and that it codes for a protein called a transcription factor which, when released, targets a range of genes under its control and regulates their activity. In this way, FOXP2, while not being the "language gene" itself, is some sort of master controller of a whole orchestra of genes, all or many of which may be part responsible for our unique human language faculty. The question, ever since the discovery of FOXP2, is "what are the members of this orchestra and what do they do?"
Now Geschwind and co. are beginning to supply the answer - thanks to some ultra-modern genomics technology as wielded by Todd Preuss at Emory University. Basically, they gene-engineered human brain cells in which they could either turn FOXP2 on or off, or substitute human for chimp FOXP2 and turn it on or off. The cell lines could be interrogated to see exactly which genes were targeted by the different versions of FOXP2. Human and chimp FOXP2 behaved very differently in the way they regulated their down-stream orchestras. They discovered 116 genes whose regulation seemed connected only to the activity of the human form of FOXP2. Many of them were active in the brain, others in non-nervous system tissue and also cranial structures associated with language function. As they say: "FOXP2 has been the window, but the network is going to be the story". Now that they have drawn the network - the subservient genetic orchestra - they can look at each gene to determine its function and, hopefully, shed more and more light on what underpins language. They have, so far, discovered 5 genes in the network - AMT, C6orf48, MAGEA10, PHACTR2, and SH3PXD2B - which appear to have been positively selected and no doubt these will be among their first investigations as to function.
This is an incredibly important and exciting step and opens the way to a methodical and purposeful slog through the genome to put the complex picture of the genetic foundations of language together. This will be a space well worth watching!
The work concerns the gene FOXP2 - star of chapter 2 in my book, THE LANGUAGE GENE THAT WASN'T. Most will recall that FOXP2 is at the root of an extraordinary speech AND language disorder in an extended London family, that it has accumulated two mutations inside the last 200,000 years (compared to the chimp), that it appears to have come under considerable selection pressure, and that it codes for a protein called a transcription factor which, when released, targets a range of genes under its control and regulates their activity. In this way, FOXP2, while not being the "language gene" itself, is some sort of master controller of a whole orchestra of genes, all or many of which may be part responsible for our unique human language faculty. The question, ever since the discovery of FOXP2, is "what are the members of this orchestra and what do they do?"
Now Geschwind and co. are beginning to supply the answer - thanks to some ultra-modern genomics technology as wielded by Todd Preuss at Emory University. Basically, they gene-engineered human brain cells in which they could either turn FOXP2 on or off, or substitute human for chimp FOXP2 and turn it on or off. The cell lines could be interrogated to see exactly which genes were targeted by the different versions of FOXP2. Human and chimp FOXP2 behaved very differently in the way they regulated their down-stream orchestras. They discovered 116 genes whose regulation seemed connected only to the activity of the human form of FOXP2. Many of them were active in the brain, others in non-nervous system tissue and also cranial structures associated with language function. As they say: "FOXP2 has been the window, but the network is going to be the story". Now that they have drawn the network - the subservient genetic orchestra - they can look at each gene to determine its function and, hopefully, shed more and more light on what underpins language. They have, so far, discovered 5 genes in the network - AMT, C6orf48, MAGEA10, PHACTR2, and SH3PXD2B - which appear to have been positively selected and no doubt these will be among their first investigations as to function.
This is an incredibly important and exciting step and opens the way to a methodical and purposeful slog through the genome to put the complex picture of the genetic foundations of language together. This will be a space well worth watching!
Wednesday, 11 November 2009
Cafe Scientifique - Medway - TONIGHT!!
I am talking tonight at the Medway Cafe Scientifique - held at 7.30 p.m. at the Innovation Centre, Medway, Phase 2, Maidstone Road, Chatham, Kent ME5 9FD.
Language Affixation In Non-Human Primates
This research group, which included Harvard psychologist Marc Hauser (author of the "humaniqueness" concept), wondered, while stating firmly that genuine language competence was unique to humans, whether or not components - building-blocks - of language competence could be found in monkeys. Using cotton top tamarins they show that the monkeys can discriminate bisyllabic words that either start (prefix) or end (suffix) with the same syllable. This is similar to the affixation rule we use to inflect words, for instance with the past tense, as in walk/walked. They conclude - in their abstract: "These results suggest that some of the computational mechanisms subserving affixation in a diversity of languages are shared with other animals, relying on basic perceptual or memory primitives that evolved for non-linguistic functions."
Tuesday, 10 November 2009
Words And Gestures Translated By Same Brain Regions
It has long been suspected that language evolved from the ability to transfer meaning through gesture. This American study shows that the same areas in the brain - the anterior and posterior temporal lobe regions we call Broca's and Wernicke's areas - are used, not only for translating gestures that constitute sign language - which has a grammar and structure - but also for translating gestures that convey meaning without resort to words and phrases: pantomimes mimicking actions or objects, and emblematic gestures like a hand sweeping across a forehead to indicate "Phew! It's hot in here!" As one of the lead researchers is quoted saying: "Our results fit a longstanding theory which says that the common ancestor of humans and apes communicated through meaningful gestures, and, over time, the brain regions that processed gestures became adapted or using words.....If the theory is correct, our language areas may actually be the remnant of this ancient communication system, one that continues to process gesture as well as language in the human brain."
It may be that Wernicke's area serves as a storehouse for words out of which Broca's area selects the most appropriate match. These researchers also suggest that these regions are not limited to deciphering words but applying meaning to any incoming symbols: words, gestures, images, sounds or objects.
Interestingly, the article notes, a baby's ability to communicate using gestures precedes language and you can predict a child's language skills based on their gestural repertoire in the first few months of life.
It may be that Wernicke's area serves as a storehouse for words out of which Broca's area selects the most appropriate match. These researchers also suggest that these regions are not limited to deciphering words but applying meaning to any incoming symbols: words, gestures, images, sounds or objects.
Interestingly, the article notes, a baby's ability to communicate using gestures precedes language and you can predict a child's language skills based on their gestural repertoire in the first few months of life.