Chimps Use Cleavers And Anvils As Tools To Chop Food

Interesting piece about the observations of Kathelijne Koops, together with Bill McGrew and Tetsuro Matzuzawa, on novel tool use of the chimps in the Nimba Mountains of Guinea. Because the Treculia fruits they are so fond of are very large - the size of a volleyball and weighing up to 8.5 kilos - they cannot access the food by biting into it. They use a variety of stone and wooden cleavers to splinter the fruit into manageable pieces on stone anvils. The practice is very local to this group of chimps - a local culture - and is not shared, for example, by the neighbouring Seringbara chimps.

When Fire Approaches, Chimps Keep Their Cool

Interesting article in SCIENCENOW about the work of primatologist Jill Pruetz with the Fongoli chimps, regarding their behaviour toward fire. Instead of panicking and totally failing to comprehend the nature of fire, she noted that the chimps reacted to brush fires by carefully forging paths to avoid the outbreaks. If you allow that human mastership of fire required three stages: conceptualizing it (meaning also to lose fear of it); starting it; and containing it, Preutz argues, you can see chimp behaviour, perhaps, as a clue as to how some putative hominin ancestors reacted to fire, which eventually led to employing fire to cook food etc. I always have a problem with "chimps give clues to origins of human behaviour" stories because we did not evolve from them. So, if the logic is defensible it is only by virtue of arguing that chimps retained some vestige of loss of fear of fire that was present in the common ancestor of chimps and humans.

Microcephaly Genes Associated With Human Brain Size.

In the third chapter of NOT A CHIMP I explain that Bruce Lahn's "quick and dirty" route to human brain evolution, based on the recent selection of variants for two genes associated with microcephaly, foundered because a number of research groups around the world, including his own, could find no links between variants of these genes and measurements of brain size in modern populations. However, this group has found a new and much more accurate way of measuring cortical surface area and they report significant associations between C.S.A. and variants of the CDK5RAP2 gene involving changes to its regulatory region. They conclude: "One particularly interesting feature of this new discovery is that the stronger links with cortical area were found in regulatory regions, rather than in the coding regions of the genes. One upshot of this may be that in order to further understand the molecular and evolutionary processes that have determined human brain size, we need to focus on regulatory processes rather than further functional characterization (changes in amino-acid sequence) of the proteins of these genes. This has huge implications for future research on the links between genetics and brain morphology."

This group did not, it appears, attempt to discover the age of the evolution of the regulatory variants they examined but it will be very interesting if they choose to investigate ASPM and Microcephalin, the two genes Lahn worked on and which tipped him into hot political water!

Does Culture Prevent Or Drive Human Evolution?

In the penultimate chapter of NOT A CHIMP I argue the case for accelerated recent human evolution, including the claim, from genome-wide trawls for signatures of selection, that as much as 10% of the human genome has undergone evolution within the last 40,000 years or less. In other words, that human demographic and cultural movement into new latitudes and geographical parts of the earth, allied to innovations such as villages and, eventually, conurbations; agriculture; and technology, have imposed a totally new set of selection pressures on human populations. A scenario in which gene-culture interactions become predominant. Here, molecular anthropologist Mark Stoneking, debates the idea, sympathetically, in a recent essay. The comments that follow are also essential reading.

The Looming Crisis In Human Genetics

Just spotted this November-dated essay in The Economist from my friend Geoffrey Miller. He provocatively claims that the crisis (for liberals) will arise in 2010 because GWAS (genome wide association studies) will turn out to tell us less about the genetic causes of mankind's diseases than the genetic variants and associations that underpin widespread genetic variation across races, ethnicities and regions. More trouble for "all men were created equal" ideologues. As Miller concludes: "If the shift from GWAS to sequencing studies finds evidence of such politically and morally perplexing facts, we can expect the usual range of ideological reactions, including nationalistic retro-racism from conservatives and outraged denial from blank-slate liberals. The few who really understand the genetics will gain a more enlightened, live-and-let-live recognition of the biodiversity within our extraordinary species - including a clearer view of likely comparative advantages between the world's different economies." Miller cites the work by Greg Cochran and Henry Harpending (which, together with work they have published in cahoots with John Hawks and Robert Moyzis) is amply referred to in the penultimate chapter of Not A Chimp - that some human groups have experienced a vastly accelerated rate of evolutionary change within the last 10,000 years - whereas others have not.

Symbolic Gestures And Spoken Language Processed By Common Neural System

Back in the saddle after the Christmas break and catching up on a few interesting items. This PNAS paper, which includes Pat Gannon as an author, compares the areas of the human brain that light up when the subject is presented with symbolic gestures, like pantomimes of actions like threading a needle, or emblems that have social significance like finger to lips to indicate "be quiet", with the speech equivalents. Both classes of stimuli, they report, activate a common left-lateralized network of perisylvian areas of temporal lobe. Their abstract concludes thus: "We suggest that these anterior and posterior perisylvian areas, identified since the 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."

Tool-Using Octopii!!

In NOT A CHIMP I very strongly make the point that the fact that chimps can make and use crude tools cannot be taken, prima facie, as evidence for cognitive, taxonomic, and genetic proximity to humans. I use the example of corvid birds, which diverged from mammalian ancestors some 180 million years ago, to make my point. But, it appears, I could have gone much further - to the invertebrates! This delicious story concerns the ability of octopii to discover submerged coconut shells, clean the silt out of them by blowing water through them, and then transporting them up to 20 metres away where they are used as a refuge against predators. If only one half of the shell has been recovered the octopus simply pulls it over its head. If it has managed to salvage the whole shell it simply creeps inside!

New Scientist Best Books Of 2009

NOT A CHIMP makes it onto New Scientist's "Best books of 2009" list!

When A Chimp Is Not A Chimp

For those of you still interested in Ardi - Ardipithecus ramidus - and what she represents to the study of human origins and the nature of the common ancestor between humans and chimps here is a nice, simple little piece from Pat Shipman ("Taking Wing' and others) in American Scientist.

No Charges To Be Filed Against Travis's Owner

Charla Nash - the woman who was horribly disfigured though being attacked by Travis the chimp in Stamford, Connecticut - has been all over the airwaves recently, including an appearance on "Oprah". While she continues to press a suit for $50 million damages, the State Attorney's office has confirmed that there are no grounds for charging Travis's owner, Sandra Herold, with anything, since she did not disregard warning signs or history of violence and Nash was known to her attacker.

Meanwhile, the take home message of this sorry affair is - don't give a primate for Christmas!

Transcription Factor Differences Guide The Different Development Of Chimp And Human Brains

In the chapter called THE RIDDLE OF THE 1.6% I explain how relatively small differences between chimps and humans at the level of DNA nucleotide sequence in genes can be tremendously amplified by a variety of mechanisms that change how hard a gene works - and when - and therefore how much protein it produces. Lisa Stubbs and Katja Nowick, from the University of Illinois, have just provided important and specific evidence for how this can come about. It has been understood for some time that some genes act as master controllers of an orchestra of subservient genes because they produce proteins called transcription factors that attach to a large number of genes and either ramp up or reduce their activity. These gene expression differences are particularly pronounced in the human brain, versus that of the chimpanzee and are involved in various processes that supply energy sources to the greedy human brain or are involved in building larger and longer synapse networks etc. etc. As Stubbs says, "These differences fit what we know because the human brain is so much larger and proteins need to be shuttled a long way out to the synapses. A higher requirement for metabolic energy has also been demonstrated independently for human brains."

The duo looked at a family of transcription factors known as the KRAB zinc finger genes and discovered 90 transcription factors that were implicated in the activity of 1000 genes - causing an upsurge of activity in the human brain. "Once this network of transcription factors is established, changes in the network can be amplified because transcription factors control other genes", says Nowick, "even a small change in transcription factor expression can therefore produce a large effect on overall gene expression differences between chimpanzees and humans." Stubbs adds that: "Our very strong bias is to believe that these transcription factors are involved in speciation and traits that make species unique"

Oxytocin Receptor Variant Linked To Empathy

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.

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

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.

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.

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."

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?.............

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.

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!

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."

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.

Chimps-R-Not-Us

Very nice review for NOT A CHIMP from LSE psychologist Christopher Badcock in Psychology Today's blog.

Primatologists Go Ape Over Ardi

Nice report from Michael Balter on primatologists being forced onto the back foot at a recent meeting to discuss the implications of the discovery of Ardi for studies of human evolution that rely heavily on chimp-human comparison. Scientists like Bill McGrew, who has done the most work on chimpanzee tool use and manufacture, reacted unhappily to the sort of statements like "no modern ape is a realistic proxy for characterizing early hominid evolution - whether social or locomotor." But it sounds like Tim White and his crew won the day and are beginning to force a re-assessment as to exactly what we should be reading into ape cognition and behaviour and the degree to which it is proving dangerous to apply it to human origins and allowing it to stand as some kind of template for humans.

Portsmouth Cafe Sci Tuesday Night

I'm doing a talk at the Portsmouth Cafe Scientifique on Tuesday night, 27th October, between 8 and 10 p.m. The Portsmouth Cafe have a lot of members from the psychology department where Kim Bard (who worked on chimp cognition at Yerkes Primate Center) is now Professor of Comparative Developmental Psychology. Should be fun!!

How Broca's Area Computes Language

In the chapter INSIDE THE BRAIN I hint at the complexity of Broca's area - one of the main speech and language processing areas of the brain. Now some researchers from UC San Diego have listened in to Broca's area by asking epilepsy patients to do simple language tasks on a laptop while implanted with electrodes meant to find and destroy the sites of epileptic lesions. As they repeated words verbatim, or produced them in grammatical forms like their past tense or plural, the electrodes measured the time and place of electrical activity in Broca's. They found patterns of neuronal activity indicating lexical, grammatical and articulatory computations separated at 200, 320 and 450 milliseconds after the target word was presented. Although these different computations were done serially, the parts of Broca's area involved appeared to overlap. As principal investigator Eric Halgren says: "These results suggest that Broca's area actually consists of several overlapping parts, performing distinct computational steps in a tightly timed choreography, a dance that may simply have been undetectable due to the level of resolution of previous methods". Crucially, the article says, information about the identity of a printed word arrives in Broca's area very quickly after it is seen, and in parallel with its arrival in Wernicke's area. It had previously been thought that reception of words (reading and hearing) was the exclusive preserve of Wernicke's area, situated more posteriorly than Broca's, while Broca's area dealt exclusively with expression (speaking). This is clearly out of date. As one of the scientists involved, Ned Sahin, says: "Broca's area has several roles in both expressive and receptive language."

Not A Chimp, Not Even Close

I have just put a commentary on the OUP US blog about the relevance of the discovery of Ardipithecus ramidus - Ardi - to the general thrust and argument of NOT A CHIMP. Basically, it's bad news for those scientists who over-stress the proximity of humans and chimps and have assumed that the common ancestor of both chimps and man must have looked very much like a chimp.

Understanding Others' Regret: An fMRI Study

An article in this week's PLoS 1 journal from the Giacomo Rizzolatti stable in Italy. They used fMRI to measure activity in parts of the brain when subjects felt regret, or witnessed a regretful outcome for someone else, on a gambling task. The same parts of the brain were activated on both occasions - the ventromedial prefrontal cortex, anterior cingulate cortex and hippocampus. This "resonant" mechanism in this context, they believe, demonstrates mirror system action involving a complex, cognitively-generated emotion, rather than a basic emotion like fear or hate.

Chimps Will Help But You Have To Ask

Most of the experiments contrived to test chimpanzee altruism centre around food sharing - which chimps are not good at because they do not do it in the wild. Therefore most researchers conclude chimps are very selfish. Here Shinya Yamamoto and colleagues decided to frame the question differently by having a chimp give or withhold an implement necessary to access food from another chimp. A pole to retrieve out-of-reach food, or a straw to push into the hole on a drinks carton, for instance. They noted that chimps were more likely to help out by making the tool available to another chimp than expected. This was more likely to happen if the chimps were related, as in a mother-offspring pair, or if the requester was a dominant. The chimps would only make the tool available if the other chimp begged for it, suggesting they were unable to read the other chimp's predicament and intentions unless an obvious sign of need was made. This suggests again that chimps may lack aspects of theory-of-mind we humans have and which informs our behaviour toward each other.

Chimp Owner Seeks To Limit Victim's Claim

Nice little piece about the attempt of Sandra Herold's attorney (Herold owned the chimpanzee Travis who went berserk and mauled her friend in Stamford, CT last February) to limit the potential damages of the ensuing legal case by claiming that, since the friend, Charla Nash, was also an employee of Herold's trucking firm, and was helping round up the escaped Travis at the time, and that Travis was heavily identified as the trucking firm's logo, the attack was an industrial accident and not simply the wanton berserk attack of a wild animal for which Herold should shoulder responsibility. Under worker's compensation she would receive far less than the $50 million suit presently leveled against her!

BBC Radio Ulster "Sunday Sequence"

I can be heard debating chimp cognition and the value or otherwise of according them human rights on Radio Ulster's "Sunday Sequence" today - 11th October. To my surprise, William announced, just before we were to go to record, that he had studied at Princeton under Peter Singer, the philosopher who started off the Great Ape Project! It added a certain friendly bite to the proceedings!! It will be on BBC iPlayer for one week.

Vocal Imitation In Bats

Behavioural ecologist Mirjam Knornschild has been studying vocal imitation in sac-winged bats (Saccopteryx bilineata) in Costa Rica. Like song-birds and baby humans, the young bats begin babbling between 2 and 6 weeks old and this babbling slowly progresses to complete renditions of territorial songs. The young bats did not learn only from adult male kin, but from any mature harem male, who acted like a tutor. This bears uncanny similarity to the research on zebra finches by Constance Sharrff, which found that, like humans, there was a window when vocalizations could be learned and that expression of the gene FOXP2 soared in those parts of the avian brain associated with vocal learning and production. We already know (see my chapter THE LANGUAGE GENE THAT WASN'T in NOT A CHIMP) a number of bat species show considerable sequence variation on the FOXP2 gene. It would be very interesting to see if FOXP2 expression rose significantly in the young bats' brains, and where, during this period of acquisition of vocalizations.

New Light On The Origin Of Man

I've been trawling in more detail through the 11 papers in this special issue of Science. Most of them are heavily tarred with C. Owen Loveday's brush, and not everyone out there agrees with him, but he has assembled a persuasive argument that today's African apes could not have resembled the common ancestor between apes and humans, that human ancestors did not pass through an ape-like phase on their way to becoming human, and that the common ancestor probably possessed a number of features we more commonly associate with monkeys, older Miocene apes, and very old recent fossil discoveries like Toumai and Millennium Man. If Lovejoy, White, and their colleagues are right, modern apes like the chimpanzee have evolved greater changes to their skeleton than humans have in this last 6 million years - i.e. they have evolved at least as far and as fast as have humans albeit in different directions, since the split from the last common ancestor. It is clear that we cannot use chimpanzees as any kind of template for human evolution, whether we are talking about bones, brains, teeth or behaviour. Here are some notes I made, including some quotes from various Science articles I consider important:

“We have seen the ancestor and it is not a chimpanzee”, says Tim White. This means Ardi is not a transitional form between chimps and us. Although about as tall as a chimp, and with a brain-size to match, she did not knuckle-walk or swing through the canopy. She walked upright and probably ate nuts, insects and small mammals. A “facultative” biped.

There is interesting detail about the skull . Ardi’s lower face “had a muzzle that juts out less than a chimp’s; the cranial base is short front to back indicating that her head balanced atop the spine as in later upright walkers, rather than to the front of the spine, as in quadrupedal apes. Her face is in a more vertical position than in chimpanzees and her teeth, like those of all later hominins, lack the dagger-like sharpened upper canines seen in chimpanzees. The team realized that this combination of traits matches those of an even older skull - 6-7 million years - Sahelanthropus tchadensis (Toumai) found by Brunet in Chad. They conclude that both represent an early stage of human evolution, distinct from both Australopithecus and chimpanzees.... Another earlier species of Ardipithecus, kadabba, dated 5.5 to 5.8 mya - perilously close to estimates of chimp-human divergence - is part of that same grade and its teeth match another ancient specimen - Orrorin tugenensis (Millennium Man) -which dates back to over 6 mya.

Ardi’s foot is interesting in that she has the big, opposable big toe - which is a primitive characteristic, but the four other toe bones are shaped so as to allow the foot to act as a rigid lever as she pushes off on it - unlike the toes of a chimp which all curl flexibly like a hand, and more like the foot of monkeys which spring rather than manipulate their way through the canopy. “The upper blades of Ardi’s pelvis are shorter and broader than a chimp’s. They would have lowered the trunk’s centre of mass allowing her to balance on one foot at a time as she walked. Lovejoy also infers from Ardi’s pelvis that the spine was long and curved like a human’s, rather than stiff and short like a chimp’s. These changes suggest to him that Ar. ramidus “has been bipedal for a very long time”’.

Lovejoy et al on hands:- “Ardipithecus hands were very different from those of African great apes. Its wrist joints were not as stiff as those of apes, and the joints between their palms and fingers were much more flexible. Moreover, a large joint in the middle of the wrist (the midcarpal joint) was especially flexible, being even more mobile than our own. This would have allowed Ardipithecus to support nearly all of its body weight on its palms when moving along tree branches (palmigrade movement), so that it could move well forward of a supporting fore-limb without first releasing its grip on a branch.

This discovery ends years of speculation about the course of human evolution. Our ancestors’ hands differed profoundly from those of living great apes, and therefore the two must have substantially differed in the ways they climbed, fed, and nested. It is African apes who have evolved so extensively since we shared our last common ancestor, not humans or our immediate hominin ancestors. Hands of the earliest hominids were less ape-like than ours and quite different from those of any living form.

Ardipithecus also shows that our ability to use and make tools did not require us to greatly modify our hands. Rather, human grasp and dexterity were long ago inherited almost directly from our last common ancestor with chimpanzees. We now know that our earliest ancestors only had to slightly enlarge their thumbs and shorten their fingers to greatly improve their dexterity for tool-using.”

Absence of knuckle-walking is a clincher. Our ancestors never did it - which, as Science puts it, “throws a monkey-wrench into a hypothesis about the last common ancestor of living apes and humans.” It could just all mean that the common ancestor looked more like ancient African apes than chimps and gorillas - rather than human ancestors passing through a chimp-phase in which chimps and gorillas remained. Which would mean that chimps and gorillas independently arrived at their numerous similarities (since gorillas split off earlier than 5 to 7 mya at 6.2 to 8.4 mya). This is very hard to swallow. David Pilbeam, for one, remains somewhat skeptical - and still leaves room for a version of evolution which has our ancestors moving through a chimp-like phase.

Ardipithecus Forces Re-examination Of Human Origins

The entire special edition of SCIENCE, mainly devoted to papers detailed the extraordinary find of a female Ardipithecus ramidus - dated 4.4 million years old - in Ethiopia has been made free to view by the AAAS. This is an astonishing find with multiple repercussions for the way we view our evolutionary relationship with the rest of the great apes and the extent to which we tend to use them - especially the chimpanzee - as some evolutionary template for the last common ancestor 6 million years ago, and aspects of our own cognition.

I have cautioned several times in NOT A CHIMP that it makes no sense to see - as Frans de Waal does - both the chimpanzee and bonobo as some kind of template for our own behaviour. My feeling has always been that it is dangerous to assume that either of these apes can tell us very much about what the last common ancestor looked like, nor how it behaved. Chimps have been evolving since that split 6 million years ago, its just that we know so very little about the details of their evolutionary trajectory since then, compared with the little we know about hominid evolution.

Ardipithecus was about 4 foot tall and had a brain about the same size as a modern chimp. But it walked upright while retaining a powerful, grasping big toe - so it is clear that it lived in woodland as opposed to open savanna, and climbed trees as well as walking on the ground. Of huge interest is its dentition and the likely fact that there is very little sexual dimorphism between male and female. The projecting canines so typical of many other primate species are already very much reduced and this, together with the fact that males are only slightly bigger than females (like us), suggests that sexual competition was very much reduced. The commentary paper by anthropologist C. Owen Lovejoy spells this all out: "One effect of chimpanzee-centric models of human evolution has been a tendency to view Australopithecus as a transitional between an ape-like ancestor and early Homo. Ardipithecus ramidus nullifies these presumptions, as it shows that the anatomy of living apes is not primitive but instead has evolved specifically within extant ape lineages. The anatomy and behaviour of early hominids are therefore unlikely to represent simple amplifications of those shared with modern apes. Instead, A. ramidus preserves some of the ancestral characteristics of the last common ancestor with much greater fidelity than do living African apes. Two obvious exceptions are its ability to walk upright and the absence of the large projecting canine tooth in males, derived features that Ardipithecus shares with all later hominids.....Loss of the projecting canine raises other vexing questions because this tooth is so fundamental to reproductive success in higher primates. What could cause males to forfeit their ability to aggressively compete with other males? What changes paved the way for the later emergence of the energy-thirsty brain of Homo? Such questions can no longer be addressed by simply comparing humans to extant apes, because no ape exhibits an even remotely similar evolutionary trajectory to that revealed by Ardipithecus."

Lovejoy posits a major shift in life-history strategy that has transformed the social structure of early hominids, reducing male-to-male conflict, and combining three previously unseen behaviours associated with their ability to exploit both trees and the land surface: regular food carrying, pair-bonding and hiding of the outward signs of female ovulation. He concludes: "Together, these behaviours would have substantially intensified male parental investment - a breakthrough adaptation with anatomical, behavioural and physiological consequences for early hominids and for all of their descendents, including ourselves".

Nothing that has happened in the field of human origins equals this find as a cautionary tale for those who would go beyond using the chimpanzee as a valuable tool for charting our origins - by virtue of it being our nearest living relative in terms of DNA - to making dangerous assumptions about how chimpanzees directly inform our own evolution and can be used as a template for it. As I have said all along - we need to keep chimps more at arms' length!

Madness, Creativity And Human Brain Evolution

The putative link between mania and creativity refuses to go away. In the final chapter of NOT A CHIMP I describe how many of the genes implicated at one time or another in schizophrenia, appear to have been positively selected both in the primate lineages and, uniquely, in the human lineage. All these positively selected genes are active in the brain where they seem responsible for synapse development, and the many energy producing processes that fuel the brain's activity. The implication is that the human brain is now running at optimum and that anything that throws a spanner into its metabolic works could produce the effects we diagnose as mental illness.

Szabolcs Keri, from Semmelweis University in Hungary has concentrated on just one of these genes that, on the one hand, develops and strengthens the communication between neurons, and, on the other, can predispose to schizophrenia - neuregulin 1. He has shown that volunteers with a certain variant of this gene perform particularly well on tests for intelligence and creativity, while, as we know, another variant of the gene is a prime schizophrenia suspect. He observes, "molecular factors that are loosely associated with severe mental disorders but are present in healthy people may have an advantage enabling us to think more creatively". The article concludes: "In addition, these findings suggest that certain genetic variations, even though associated with adverse health problems, may survive evolutionary selection and remain in a population's gene pool if they also have beneficial effects".

Spotted Hyenas Cooperate Better Than Chimps

Some fascinating research by a comparative psychologist, Christine Drea, from Duke University, who has had trouble getting this sort of stuff published in the past because it was outside the mainstream of comparative cognitive psychological research. She has shown that spotted hyenas out-perform chimps on tasks that require them to learn how to cooperate by pulling synchronously on two ropes to release a food reward from the palette they are tied to. Chimps are notoriously bad at these cooperative tasks and require extensive and long-winded teaching, but the hyenas figured out how to do it very quickly and under their own steam. When a naive animal was paired with an experienced socially dominant animal the latter would temporarily suspend dominant behaviour and submissively follow the lower-ranking animal, only to re-assert itself once the task was ended. The only pairing that performed poorly were two highly dominant animals. The tasks were performed in silence but there was a lot of mutual gaze-following going on.

So here we have a species evolutionarily remote from chimps out-performing them in very much the same way, on a very similar task, that bonobos - very closely related to chimps - do. It is yet more evidence that advanced social cognition is not strictly reflective of genetic proximity but social structure. As the article says, "Researchers have focused on primates for decades on the assumption that higher cognitive functioning in larger-brained animals should enable organized team-work. But Drea's study demonstrates that social carnivores, including dogs, may be very good at cooperative problem-solving even though their brains are comparatively smaller. "I'm not saying", says Drea, "that spotted hyenas are smarter than chimps just that they are more hard-wired for social cooperation". What I say is that cognition is taxonomically blind. It is an adaptive tool to do an adaptive job and here it arises out of social structure.

Tracing The Origins of Human Empathy

Rather nice piece in the Wall Street Journal, by Robert Lee Hotz, which blends Frans de Waal's latest comments about empathy in apes and monkeys with allusion to the sort of brain research on empathy I discuss in a chapter in Not A Chimp called INSIDE THE BRAIN.

Michelangelo Signorile Show

I did a 15 minute interview, live over the phone line from the UK, on Sirius XM's "Michelangelo Signorile Show" - one of the biggest pay-to-listen shows on US Radio.

Amygdala Responsible For Our Sense Of Personal Space

Here's a nice "social brain" story from Ralph Adolphs, professor of psychology and neuroscience at Caltech. Using a unique patient, SM, who has bilateral lesions to the amygdalae they have been able to establish that the amygdala alerts us to when people literally "get in our face". SM behaves totally inappropriately socially in that she can tolerate people approaching her practically nose to nose and does not observe reasonable social distance herself. She cannot interpret fear in faces and find trouble gauging other peoples' trustworthiness. She is just too friendly. Their findings may link to autism studies because autistics have problems with the concept of appropriate social distance and have to be taught what it is.

Researchers Map Chimpanzee Facial Emotions

Kim Bard, now director of the Centre for the Study of Emotion at Portsmouth - formerly from Yerkes Research Centre in Atlanta, has been developing a "Baby Chimp Facial Action Coding System" to classify the wide range of facial emotions in chimps. Baby chimps may have an even larger range of facial emotions than human infants, she says, and may be better at controlling their emotions when very young. They claim to have found 16 variations of smile on the face of the chimp, compared with 13 in human babies and 5 different varieties of the fear grin.

Huffington Post Review For "Not A Chimp"

NOT A CHIMP was released in the US and Canada this week and the influential Huffington Post is the first to review it. Although neuroscientist Dan Agin disagrees with the book's premise he concludes:

Into this debate about similarities and differences between chimpanzees and humans now arrives a new book by Jeremy Taylor, a UK BBC science journalist and film producer. It's an interesting and readable book, particularly since Taylor takes a strong position in the debate. His focus is on differences, but his argument is biological rather than religious or philosophical. He makes three main points:

1) We have been evolving much faster than the chimpanzees. The rate of evolution in the human genome has apparently increased since we and the chimps split from a common ancestor. At least 7 percent of human genes have evidently changed within the past 50,000 years.

2) We humans have apparently domesticated ourselves in exactly the same way that we have cultivated farm animals, dogs, and crop plants from their wild progenitors.

3) Taylor believes that misguided scientists have suggested a closer genetic relationship between humans and chimpanzees in order to build sympathy for an endangered species.

These are strong views. Many people (including myself) may be opposed to Taylor's conclusions, but this is a provocative book that should be read by anyone interested in the debate about similarities and differences between humans and chimpanzees.

How Humans Became Such Other-Regarding Apes

Really nice essay on the essential differences between humans and the rest of the higher primates from an old friend of mine, the anthropologist Sarah Blaffer Hrdy - based on her most recent book MOTHERS AND OTHERS. Hrdy argues that the crucial wide differences between the species come in the social realm and involve huge increases in the human propensities for mutual tolerance, social communication and intention-reading.

Explaining Wolf-Dog Differences In The Ability To Follow Human Cues

In the chapter on domestication in NOT A CHIMP I present evidence showing that dogs are much better than chimps and wolves (from whom dogs are supposed to have evolved) at following human pointing gestures as to the location of food. I also show that tamed Arctic foxes are as good as dogs on these sorts of tasks. So, have dogs (tamed wolves) and tamed foxes evolved some aspects of social intelligence that is peculiar to the domestication process, and, if so, what? Adam Miklosi and colleagues from Eotvos University in Hungary have added a little complexity to the story. They show that socialised young wolves are capable of following simple human pointing cues after all - though there is delayed emergence of these social skills compared with dogs. The young wolves had been human-reared and bottle fed since pups. The experimenter drops food into bowls in a hidden way by turning away from the subject. On turning back and placing bowls to her left and right she signals with a finger point which bowl has the food - it is not possible, because of the equipment, for the animal to use its own sense of smell. The wolves equaled the performance of dogs on the simpler task where the pointing finger is less than 50 cm. from the bowl, but slightly worse which the pointing gesture was more distal - in excess of 50 cm. Also, the wolves took longer to attend to the experimenter - they took longer to establish eye contact, stop wrestling with their handlers and stop attempting to bite the experimenter! The researchers conclude that, while the difference between human reared wolves and dogs on these tasks is not as marked as previously thought, the delay in the wolves suggests they do not react to the same extent to extensive socialisation as the dogs which "are able to control agonistic behaviours". In other words the dogs are still slightly ahead because their natural tendency for fight or flight has been bred out of them over thousands of years of co-existence with humans. They therefore find it easier to fix attention on humans with less fear and aggression.

Chimps Develop "Specialised Tool Kits" To Catch Army Ants

A research team from the Goualougo Triangle Ape Project, headed by Crickette Sanz, have provided evidence that chimp tool-making and use to dip for several species of ant is more sophisticated than previously thought. Chimps generally use a long twig to actually dip for the ants - the ants climb up the twig and are thus transported to the chimp's mouth. But, where they have to break into the nest, they use a different twig tool to penetrate the nest and make an opening. Specifically, the number of tools used per site was an average of 3.37 and just over one third of recovered tool sets contained a mixture of nest perforating and ant dipping tools. There was evidence that the nest perforation tools were selectively used by the chimps to open the nests of the more aggressive epigaeic ants - where wholesale smashing of the nests would release swarms of highly aggressive biting ants driven with retaliatory intent. Using a perforation tool is clearly a more delicate technique to control ant emergence and collateral damage to self. However this report is tarnished, in my eyes, by a couple of highly anthropomorphic observations attributed to the researchers. The first is that by delicately perforating the nests, rather than smashing them, the chimps are practicing "sustainable harvesting". This begs the assumption that chimps have a deep forward planning knowledge which allows them to manage resources long into the future - which is not sustained by the mainstream of primatological research. The authors also assert that the chimps practice recycling by re-using tools that have been left by other individuals. I hope that, in the original paper, they word it to say that the effect is to recycle - rather than the intent is to recycle!

Early Tools Were Born Of Fire

How long ago did early humans begin using fire to make tools? Previous reports suggest it was a relatively new invention - dating back a mere 30,000 years or so. However, a team from the University of Capetown have re-calibrated the event. They discovered that it was impossible for them to re-create the stone tools found at the Pinnacle Point caves in South Africa unless they used 20 to 40 kilograms of hardwood and heated the silcrete from which they were fashioned to more than 300 degrees C over 30 hours. Tests reveal that original heat-treated tools are at least 70,000 years old and may even be as old as 164,000 years. So, humans had a much more sophisticated fire-assisted technology, earlier than previously thought. My interest lies in Richard Wrangham's theory for cooking being the explosive force behind earlier human brain expansion. His theory is be-deviled, so far, by lack of evidence for hearths going back 2 million + years. Evidence suggesting a far more sophisticated use of fire than that for cooking, dating back to the earliest origins of Homo sapiens in Africa, pushes the boundary of fire technology deeper into the past and may help make Wrangham's theory more tenable.

Chimps Can Be More Rational Than Humans

Whatever the rampant growth of human neo-cortex does it does not always make us more rational than other animals. Keith Jenson, Josep Call and Mike Tomasello, from the Max Planck Institute in Leipzig, compared humans and chimps on species-suitable versions of the ultimatum game in which one individual is expected to maximize assets he is given by being miserly toward the second partner. The assumption is that humans will be rationally self-interested - indeed the idea underpins most of economics. However, humans play irrationally because they factor in notions of fairness and cooperation such that they give more than they "should". This clearly reflects the intense evolutionary development of our "social brain". Chimps, however, are ruthlessly rational - giving the tiniest amounts away. The other partner in the game seems always happy with whatever crumbs he receives.

Human Chimp Interbreeding Challenged

As this fascinating Nature piece explains, in 2006 David Reich and colleagues from the Broad Institute in Cambridge, MA compared the genomes of humans, chimps and three other primates and concluded that the divergence of human and chimp ancestors could not have been a clean break but was a messy business involving more than 4 million years and two splits - an initial divide followed by a long period of interbreeding, and then a final separation in which only the young X chromosome was retained. It was the apparent youth of the X chromosome, compared with all the non-sex chromosomes, that demanded this explanation.

Now, however, Soojin Yi and colleagues, from the Georgia Institute of Technology, have challenged an interpretation which has always proved difficult to swallow for the genomics community at large. No need to involve complex speciation, they argue, because the data can be explained by a well-known difference in female promiscuity ranging from high in chimps, through intermediate in humans, to low in gorilla. High female promiscuity leads to relatively large testes and sperm counts. This means, says Yi, more rounds of cell division making all that sperm - in chimps - which increases the mutation load on chimp sperm - more mutations in males than females. This male-biased mutation rate will favour non-sex chromosomes, the mutation rate in the X will be lower, and, since the molecular clock of evolution is calculated in mutation over time, the X will therefore appear to be younger - when, in fact, it is not. Reich challenges back but, at least, as Nick Barton suggests, we now have an exciting alternative explanation for the chimp-human divergence which can be tested. Watch this space!

Novel Genes Made Us Human

Here is an extremely novel approach to explaining the origin of genes unique to the human line. David Knowles and Aoife McLysaght, from the Smurfit Institute of Genetics in Dublin, have identified 3 genes that are present in the human genome but not present in the chimp. They appear to have been made active in humans from inactive sequences of DNA in chimps and a range of other primates. The researchers have determined that these genes are active in humans because they do produce protein but they have no information yet on what, exactly, these genes do. They do point out, however, that they have only filtered about 20% of the human genome for human-chimp comparison and that their research may yet realize some 18+ genes that have arisen from non-coding DNA in human evolution.

Latest News On Dog Evolution

In the chapter on domestication in NOT A CHIMP I favour a version of dog evolution which posits that humans did not actively go out to tame wild wolves but that, if anything, wolves are too large to have been likely dog progenitors and that at least the early stages in the evolution of dogs involved a loose form of commensalism in which a smaller wolf-like species or other wild canid tamed itself by selecting for the ability to tolerate human proximity while foraging in rubbish dumps on the periphery of early human settlements. This still leaves open the question of likely dates during which this process might have occurred. Now Peter Savolainen and a number of Chinese colleagues have examined mitochondrial DNA from wolves and extant dogs and decided that the cradle for domestication of dogs was in China, probably just south of the Yangtse river, about 16,000 years ago. Humans and dogs subsequently ranged widely over Asia and dogs thereby wound up in Natufian settlements in present-day Israel by about 11,000 years ago. 16,000 years ago was the earliest time for a change from hunter-gatherer to sedentary agriculturalists in present-day China, and the beginning of rice cultivation. These researchers believe the progenitor was the smallish Chinese wolf, and, while nodding in the direction of the commensalism theory, they clearly favour a more active role for humans in selection among wolf females for tamable offspring. This runs counter to a large body of information on wolves that suggests they are, effectively, un-tamable. Interestingly they present a completely new angle on the motivation for this supposed domestication of wolves by suggesting they were used as a food resource! The Chinese are reputedly fond of dog-meat to this day but I think this is a shaggy dog domestication story!

Milk Drinking Started 7,500 years Ago In Central Europe

The one gene among approximately 2,000 that appear to have evolved uniquely in humans within the last 40,000 years about which there is no argument is that for lactase. A mutation arose some 7,500 years ago which allowed human groups carrying it to persist with lactose digestion in milk and milk products beyond childhood. Until recently it was held that the source of this mutation, and its early spread, occurred in northern European latitudes because of a need to bolster calcium to aid vitamin D synthesis. This is where the mutation exists at highest frequency today. However, Mark Thomas and colleagues, from UC London, using computational techniques, have placed the origin of the mutation somewhere between the central Balkans and central Europe, probably among the so-called Linearbandkeramik culture. Dairy farmers carrying this gene variant, they say, underwent more widespread and rapid population growth than non-dairying groups and this spread of fresh milk drinking from the Balkans across Europe explains why most European lactase-persistent people carry the same version of the gene - it surfed on a wave of population expansion that followed the rapid co-evolution of milk tolerance and dairy farming.

The Origins Of Human Handedness

Nice, succinctly written piece on ScienceBlogs by Michael Balter on the evolution of human handedness. As has been pointed out in an earlier post here, humans are unique in having a species-wide handedness preference - 85% of all humans are right-handed, whereas, while other higher primate species do demonstrate handedness, it is not consistent and species wide. Balter reports the research and thoughts of University of Liverpool researcher Natalie Uomini who conducted a number of "stone age" tasks with children and adults and noted that while they might use either hand for simple tasks, they showed pronounced handedness preference the more complex the manual task became. It is as if, she says, "they had to make their minds up which hand to use" when confronted by complex manual tasks. Teaching of techniques via demonstration would also have maintained the hand preference because learners tend to copy the way the teacher's hands are used. Certainly there is strong evidence from skeletons for handedness in Neanderthals, and Homo heidelbergensis - so this dates back to at least 500,000 years, though Uomini, Balter reports, takes umbrage with Nick Toth's assertions that bias in the way flakes are shaved off stone tools suggests handedness as far back as Homo ergaster - about 1.6 million years ago. One expert flint maker, she says, could have made most of all flints found at a single camp and so it is wrong to represent the many flints found as separate data points. You cannot assume the hand preference extended to all individuals at the time.

Mirror Neurons And Encultured Babies

A little piece in LiveScience about the recent work of Victoria Southgate, at Birkbeck College, London. Using EEG she has documented the employment of mirror neurons in babies 9 months old that fire when babies both watch people reaching for objects or perform the same motor task for themselves. Interestingly, this mirror neuron behaviour proved to be predictive in that it was amenable to training. Once the baby had seen a hand appear from behind a curtain to grab something, it would fire just before the hand grabbed on future trials. Livescience report Southgate making the point that this could lead to accurate responses to others' actions, including interception and underpin the first steps babies make into the social world because it allows them to take part in collaborative activities.

Why Humans Talk And Chimps Don't

It's a fertile time, at the moment, for interesting comparative functional neuroscience! Here an article reports on recent work on Broca's Area, by Chet Sherwood and team. They sectioned and examined Broca's Area from a dozen chimps and discovered that there is no left-right asymmetry in terms of number of neurons and that there were a lot of individual differences in the size, location and symmetry of Broca's Area, rather than a pan-species norm - as exists in humans. Neither was the handedness of the chimps in any way related to symmetry of Broca's (Broca's Area in chimps has been related to the use of hand gestures and tool use). Furthermore, they notice that, while the human brain in total is some 3.6 times larger than the chimp brain, Broca's Area in the human is 6 times larger than in the chimp. It has ballooned in the human lineage.

Precursors To Human Language Neuro-circuitry Found In Macaque

The two main language areas of the human brain - Broca's Area and Wernicke's Area - are connected by a major bundle of fibres called the arcuate fasciculus, which also ramifies extensively in the temporal lobe and in areas adjacent to Broca's Area in the frontal lobe. From what areas of the primate brain did the brain structures necessary for language evolve? Michael Petrides and Deepak Pandya, in this PLoS Biology article, report detailed tracing of pathways in the macaque brain they think are those evolutionary precursors. The detailed forensic work is made possible by the injection of radiographic dyes into the white matter nerve fibres. The dye runs along the network allowing tracing to occur. This is their summary:

"Two distinct cortical areas in the frontal lobe of the human brain, known as Broca’s region, are involved with language production. This region has also been shown to exist in nonhuman primates. In this study, we explored the precise neural connectivity of Broca’s region in macaque monkeys using the autoradiographic method to achieve a level of detail impossible in the human brain. We identified two major streams of connections feeding into Broca’s area: a ventral stream from the temporal region, which includes areas processing auditory, multisensory, and visual information and a dorsal stream originating from the inferior parietal lobule and the adjacent superior temporal sulcus. Our detailed connectivity analysis illuminates the pathways via which posterior cortical areas can interact functionally with Broca’s region, in addition to contributing to an understanding of the evolution of language. We suggest that a fundamental function of Broca’s region is to retrieve information in a controlled strategic way from posterior cortical regions and to translate this information into action. This fundamental function was adapted during evolution of the left hemisphere of the human brain to serve language."

Specifically, what they have found is that one of the component parts of Broca's Area, area 45, and a related ventro-lateral area, is involved with the controlled retrieval and selection from non-verbal memory in the monkey and in the right - or non-dominant hemisphere of the human brain. In the human, this area on the left side of the brain has been co-opted for language. Specifically they say:

"During the evolution of the human brain, these high-level forms of programming (the basic elements of which are already present in the macaque monkey brain) came to include complex syntactical structure (e.g., hierarchical level of control) that is
necessary for language, and which has been argued to be a major contribution of Broca’s region. If we were to extrapolate these arguments on the basis of the present monkey anatomical study, our recording study in the monkey, and our functional neuroimaging studies of the human right hemisphere homologue of Broca’s region, we
could say that a common primate circuitry was adapted, during millions of years of evolution, in the human brain for the strategic retrieval and selection of information from verbal memory (including the mental lexicon) in posterior temporo-parietal
cortical regions by one component of Broca’s region, area 45, and the transformation of this selected conceptual information into gestural/speech acts by the other component of Broca’s region, area 44, via its connections with motor structures, such as the premotor cortex, the basal ganglia, and the rostral inferior parietal lobule. Our suggestion here is simply that an area that served higher control of action in the macaque monkey may have been adapted for the control of complex hierarchical sequences of gestural and vocal action with the evolution of communication leading to human speech."

This neatly links the complex hierarchical welding of phonemes into language with the complex and bewilderingly fast oro-facial movements necessary to articulate language in the larynx. When might this evolutionary process have occurred? The authors note that some degree of leftward asymmetry has been found in the planum temporale (associated with Wernicke's Area) in chimps as has left hemisphere dominance or the oro-facial movements involved in learned communicative vocalizations. Also, handedness has been noted for chimps connected to tool use, suggesting a left hemisphere specialization for control of complex actions involving the right hand. Remarkable asymmetry of Broca's cap has been discovered in endocasts of Homo erectus skulls, suggesting the various precursors were coming into place before manifesting themselves, much more recently, in a language faculty. The authors conclude:

"These findings are consistent with suggestions that specialization for the control of action and gesture may have preceded specialization for language. Note also that our close primate relatives, chimpanzees and bonobos, use arm/hand gestures more flexibly in their natural communication across contexts than facial expressions and vocalizations. The above facts suggest that the use of gestures for early forms of communication may have been an adaptation distinguishing the Hominoidea from other primates, and that the use of vocalization in the form of modern speech emerged much later with the evolution of language in the narrow sense, i.e., a uniquely human adaptation. It is interesting in this respect that the supralaryngeal vocal tract of humans differs significantly from those of other primates, making the human vocal apparatus unique in transmitting information at fast rates."

Thus language appears to be a combination of ancient, modern and unique evolutionary developments in the primate and hominin lineage.

Gene Regulation Is A Vital Part of Human Evolution

In NOT A CHIMP I chronicle the extraordinarily prophetical work of Allan Wilson and Mary-Claire King, a quarter century ago, which argued that mutational changes to the DNA sequence of genes - single nucleotide polymorphisms - alone could not possibly explain the myriad differences they recorded between humans and chimps. Something else had to be going on. They suggested that differences in gene regulation - the activity and timing of activity - of identical or highly similar genes would be found to be important. In those days limited genome technology prevented them from fully exploring this idea but recent work has dramatically supported their theory and shown a host of gene regulation differences between humans and chimps, especially in the brain. Now, a group of scientists which includes Carlos Bustamente and Andrew Clark, from Cornell University, has examined the phenomenon of cis-regulation - changes in DNA in non-coding intronic areas flanking more than 15,000 genes - and found patterns they interpret as a strong effect of both positive and negative selection during hominid history - and an especially strong effect of positive selection upon these regulatory sequences in genes operating in the foetal brain. As they conclude in their summary: "Our results suggest that both positive and negative selection have acted on candidate cis-regulatory regions and that the evolution of non-coding DNA has played an important role throughout hominid evolution."

Are Humans Still Evolving?

The popular view is that humans have ceased to evolve as advances in medical care, better housing and welfare, etc. etc. have leveled the playing field and eradicated the essential variability in humans upon which selection can act. The view that human evolution is grinding to a halt is cogently argued by Prof. Steve Jones, from University College, London, who points out that a former great source of mutational change was the sperm of older men. Cell division during sperm manufacture provides plenty of opportunity for mutational mistakes to occur - and in men over 50 those mistakes are far more numerous. But, says Jones, elderly fathers are rare these days - there is a dearth of aged patriarchs fathering children by multiple wives - and this is allied to far greater survival rates among offspring.

I counter that view in NOT A CHIMP by championing the arguments of John Hawks, Greg Cochran and Henry Harpending, who calculate that human evolution stagnated for much of hominin history but has dramatically speeded up in the last 40,000 years. Also, that, if you take a population geneticists viewpoint there are very many more genomes in circulation around the globe today thanks to human population explosion over the last few millennia - all potential sites for mutation.

Now, as reported in The Scientist, life history evolutionist Stephen Stearns, from Yale University, has got his hands on a wealth of longitudinal medical data collected in the famous Framingham study which has been running since 1948 - several generations' worth. With a number of colleagues he is developing an evolutionary twist to the Framingham data-bank where they are correlating variables like lower cholesterol, lower blood pressure, earlier conception and later menopause, with reproductive success (having controlled for social factors that might influence fertility). They have shown clear changes in the levels of these genetically-controlled traits in only 2 to 3 generations and are now expanding the study to include parameters like high-density lipoproteins, triglycerides and bilirubin, and to look at male reproduction. They are due to publish a detailed review of their findings on contemporary human evolution in a special issue of PNAS later this year.

Human Ancestors Were Not Knuckle-Walkers

This ScienceDaily piece reports on a recent paper by Tracy Kivell and Daniel Schmitt, in PNAS. Despite decades-worth of argument, they say, we have not yet resolved whether or not human bipedalism evolved from a terrestrial knuckle-walking ancestor, or a more generalized arboreal ape ancestor. For the first time, they have minutely compared wrist morphology among a number of primate species and conclude that two different forms of knuckle-walking have independently evolved - an extended wrist posture with bony stops to prevent the wrist from over-bending, in chimps, and a locked 'columnar' stance in gorillas where the arms and wrists extend straight down. The duo point out that there are a number of subtle differences in wrist morphology between humans and chimps which suggest to them that we did not evolve from a chimp-mode knuckle-walker but a more generalized arboreal primate ancestor.

Orang-utans Use Tools To Deceptively Communicate

Here a group of primatologists, including Carel Van Schaik, report that orang-utans use strips of leaves, placed over their mouths, to modulate the kiss squeaks they emit when in distress. The leaves drive down the frequency of the kiss squeak to give the impression that the sound is being made by a larger animal than is the case. If all this stands up to further scrutiny it will be first evidence of tool use linked to a form of communication in which deliberate deception is involved.

More Clever Corvid Stuff

Nice BBC piece which reports on work that builds on earlier amazing findings relating to corvid tool use. In the first piece of research, Nathan Emery and Christopher Bird have found that Aesop's fable about a crow enjoying a "Eureka" moment by displacing water by throwing pebbles into a jar until the water surface rose to the point that it could drink, may well be grounded in fact. Their rooks have shown that they can plop pebbles into a cylinder containing a floating worm - up to the point where they can reach the worm with their beaks. Two rooks did it spontaneously when first presented with the task, the other two on their second attempt. They used larger pebbles when given variety thereby raising the water level more efficiently and they avoided worms on sand in favour of worms floating on water.

In a separate paper, Alex Kacelnik's group in Oxford report repeating the famous experiment conducted with Betty, just before she died, where the New Caledonian crow used a short tool to retrieve a medium-length tool to retrieve a long tool to pull out food from deep inside a horizontal tube. Four out of seven birds were spontaneously able to use the tools in the correct order, repeating Betty's swansong. As I explain in the book, this is an exceptionally important finding because, had the crows been learning by simple trial and error they would have found it impossible because the reward only comes after successfully negotiating three stages of tool selection. As Kacelnik is reported saying, "We are aware that the animals probably do it by putting together, in creative ways, things that they have learned individually". This is meta-tool use - using a tool to make a tool to use a tool.....and so on, to gain a reward. This is very sophisticated, human-like, cognition.

Jumping Genes Add Diversity To Human Brain

Fred Gage's lab at the Salk Institute have just reported finding that human brain cells are hyper-variable because their DNA harbours variable numbers of small DNA elements called LINE-1 elements (formerly referred to as junk DNA) which copy and paste themselves in great numbers throughout the genome. In this way, brain cells resemble immune system cells which are also hyper-variable because they have to constantly counter the barrage of different antigens that bombard our bodies. They discovered that LINE-1 jumping occurred much more frequently in brain tissue than in tissue from heart and liver and that the LINE-1 promotor, the switch that turns LINE-1 elements on and off, is permanently switched to "on" in the human brain. In this sense, LINE-1 insertion follows a pattern of several other means of gene regulation where the brain differs markedly from other body organs, in keeping with its need to remain flexible in response to rapidly changing environmental conditions throughout life. What Gage's team have not yet looked at is whether LINE-1 insertion and self-copying is extremely different between chimps and humans. My guess, obviously, is that it will be.

Brain Difference In Psychopaths Identified.

In the chapter on neuroscience (Inside The Brain) in NOT A CHIMP I describe in detail what scientists have dubbed "the social brain" - a number of heavily interlinked brain regions that receive inputs of relevant emotional stimuli from the outside world (for instance the amygdalae receive images of fear and pain) and process them into appropriate pro-social behaviour like true empathy and the ability to plan and behave appropriately among other human beings. Besides the amygdala, other areas include the orbitofrontal cortex, the insula and the anterior cingulate cortex. People who have damage to their orbitofrontal cortices become withdrawn and anti-social and behave inappropriately. Now a team of neuroscientists from Kings College, London have discovered that in the brains of psychopaths the white matter tract that connects the amygdala with the orbitofrontal cortex - the uncinate fasciculus - has structural abnormalities when compared to the brains of normal individuals. The degree of abnormality in the UF was directly related to the degree of psychopathy. Real pathology of the social brain.

Did Malaria Jump To Humans From Chimpanzees?

This CNN piece is one of several posts today documenting the recent discovery of the genetic similarity between Plasmodium reichenowi - the form of Plasmodium (the malaria parasite) common to chimps - and Plasmodium falciparum, the form common to humans and the cause of over 1 million deaths a year. It appears to be a complete vindication of the scientific argument of Ajit Varki, reported in chapter 5 of NOT A CHIMP - called "Less Is More". Nathan Wolfe has isolated and sequenced DNA from both malaria parasites and suggests, as did Varki before him, that falciparum evolved from the common chimp parasite, reichenowi, and spread, via mosquito vector, from chimps to humans. In fact, Varki's take on this event, which could have happened at any time between 10s of 1000's of years ago to 2 or 3 million, is more interesting because it suggests that, back in Homo erectus days, reichenowi was THE common malaria parasite to humans and chimps and that humans underwent drastic evolution to their immune systems in order to counter it. For some reason, reichenowi appears to be relatively harmless to chimps today and it may have been forever thus - so chimps never did evolve resistance to it. Eventually, Plasmodium countered human resistance by evolving the falciparum form from reichenowi, though whether or not chimps were the seat of this parasite evolution - and why - remains to be seen.
If you want to read up on this in more detail the source paper is Open Access in PNAS. The URL is http://www.pnas.org/content/early/2009/07/31/0907740106.full.pdf+html The authors specifically echo Varki's argument that humans inactivated the CMAH gene in a classic "less is more" mutation to prevent the sialic acid precursor Neu5Ac making Neu5Gc - which coats chimpanzee cells. A mutation converting P. reichenowi to P. falciparum then allowed it to target the now over-abundant Neu5Ac on human cells - accounting for its extreme pathogenicity in humans today.

Orangutans Our Nearest Kin?

All the world loves a heretic, it seems. This clear piece by David Templeton, in the Pittsburgh Post-Gazette, outlines local boy Jeffrey Schwartz's continuing insistence that orangutans are more closely related to us than chimps. His argument is not based at all on genome comparisons, and particularly those calculations, based on genome divergence, that construct family trees of related species by drawing in divergence points from common ancestors (the forks in the tree). He relies on a host of morphological comparisons of which 28 are shared between human and orangutan versus 2 with chimps and 11 with gorillas. These include enamel molars, similar hairlines and shoulder blades and aspects of skull structure. His theory continues to draw scorn from over 99% of the evolutionary anthropology community and Todd Disotell, of the New York University Center for the Study of Human Origins, is preparing a point-by-point rebuttal of Schwartz's argument. Watch this space!

Is Broca's Area Asymmetry Unique To Humans?

Are humans truly unique in their cognition? Are there truly unique structures in the brain that have evolved since the split from the common ancestor of chimps and humans? As I argue in detail in the chapter INSIDE THE BRAIN: THE DEVIL IS IN THE DETAIL - it is sometimes very hard to be sure one way or another. This article summarises the perplexing question of whether the left-favouring asymmetry of Broca's Area arose in both chimp and human ancestors or only in the line leading to us. An earlier report from Bill Hopkins at Yerkes had suggested apes were also asymmetrical for their equivalent of Broca's area, though not as much so as humans. Now a recent paper by Chet Sherwood, which includes Hopkins as an co-author, argues the opposite. They find that some chimps do have a notable asymmetry in Brodmann's areas 44 + 45 - which they define as Broca's Area, but it is only a maximum of 10% and sometimes favours the right, sometimes the left. Only humans consistently show a left-favouring asymmetry which dwarfs that in chimps by a factor of 6. The authors say their results "argue anew for human uniqueness".

"Me Cheeta" Makes Booker Prize List

Nice piece in The Guardian as Zoe Williams meets up with "Me Cheeta" novelist James Lever in a Kensal Rise coffee-shop. Although this "ghost-written" autobiography of Johnnie Weismuller's famous sidekick from Tarzan days has gone through several deceits since first revealed as forthcoming by publishers Fourth Estate, it appears to be an excruciatingly wicked filleting of the Hollywood culture.

Appearance On BBC1 "The Big Qestions".

This episode of The Big Questions included a debate on "Should Apes Have Human Rights?". Colin Blakemore and I were in the con camp while primatologist Ian Redmond, philosopher Paula Casals and Paula Stibbe were the pros. The link to the BBC's iPlayer is above and the 60-minute programme (we are in the middle third) will be available for the next seven days.

What Makes Us Different?

It's all in the book but this well-written essay on chimp-human differences, by Michael Lemonick in Time Magazine, is a very digestible read.

Restating The case For Human Uniqueness

Helene Guldberg has just re-published her excellent review of NOT A CHIMP in Spiked Online.

Excellent Review In The Guardian

Excellent review for NOT A CHIMP in the Guardian Review section this morning, by Georgina Ferry, who is "impressed by an ascerbic look at primatology". As she says:"Egged on by a tendency to anthropomorphism, some primatologists have argued that the difference between chimpanzee and human cognition is simply a matter of degree. Taylor is having none of it. "To call the difference quantitative between alarm calls, food-specific grunts, whoops and Shakespeare; between night nests and twig-tools and the A380 passenger jet; and between retribution and food-sharing and Aristotle and Mill is, to my mind, stretching a point, and a bit of an insult to human ingenuity and culture".

"Taylor gives no more than a dismissive aside to chimpanzee language studies, most of which he describes as "ridden with wishful thinking, over-exaggeration, and even downright fantasy". Though this does not make for a scrupulously fair presentation of the evidence, his approach is enjoyably combative and certainly succeeds in mapping the biological, behavioural and social landscape that divides us from our next of kin."

Apes Imitate But Will Never Innovate

Interesting article from New Scientist on some latest thoughts from comparative psychologists as to whether human powers of cultural transfer of information are indeed unique. See the final chapter in NOT A CHIMP for a long discussion on this. Scientists in Leipzig formulated an experiment where four year-old children and chimps had to try and make a loop out of a piece of string in order to tow a piece of wood with a nail in it toward them for a reward. Neither species managed it on its own but only the children responded to tutoring on the making of loops - such that the majority succeeded. The chimps seemed impervious - concentrating on the outcome rather than the complicated steps needed to achieve it.
"Because apes focused on the outcome, rather than the process of creating a loop and bringing the block closer, they did not – and will never – transcend their inability to discover the solution on their own", the NS reports the lead scientist concluding. Andy Whiten, at the University of St. Andrews thinks the problem is more nuanced than that and it has to do with "over-imitation" - a slavish attention to all the details, relevant or not, in a demonstrator's actions.Chimps' imitation is good enough to allow them to copy very simple techniques but it runs out of steam the more difficult and opaque the technique being demonstrated becomes. As Whiten says: "They didn't get it. They didn't show any kind of cumulative cultural evolution. There's something rather curious going on in these non-human species, where they get stuck on simpler techniques."
The article concludes that such comparative experiments are bringing together once disparate scientific camps into general agreement on the limits to chimpanzee cultural intelligence.

Neanderthals Always Hovered On The Verge Of Extinction

According to this New Scientist piece, recent work on mitochondrial DNA from a variety of Neanderthal remains spanning Europe to western Asia - by Adrian Briggs of the Max Planck Institute for Evolutionary Anthropology in Leipzig - has concluded that genetic heterogeneity among Neanderthals was much lower than either chimps or modern humans and that, for much of their existence, there were unlikely to have been more than a few hundred thousand Neanderthals spread across this vast geographical area. Small population size, small group size and low genetic heterogeneity are a recipe for extinction. Neanderthals would not have needed roving bands of modern humans attacking them with deadly intent. Deleterious mutations would have done the trick.

"The Independent" Reviews "Not A Chimp".

A very positive review for NOT A CHIMP, from Peter Forbes in The Independent, this time stressing the genetics. Here's a flavour of it:

"That we are 98.4 per cent genetically identical to chimpanzees is one of the more misleading factoids of our time......In Not a Chimp, the TV science producer and director Jeremy Taylor gives case histories of the search for those crucial genes that make us human. The FOXP2 gene, for instance, discovered in a family with a history of language difficulties, is now known to be important for speech and comprehension in humans and, amazingly, for the ability of birds to sing......That 98.4 per cent similarity has fuelled a movement to accord chimpanzees human rights. However, Taylor demonstrates that if we are looking for the nearest thing to human intelligence, it seems to reside not in chimps, but in birds – especially crows. The record of human evolution will become dramatically clearer in five to ten years time. Meanwhile, for an idea of why we are more than a chimpanzee plus 1.6 per cent, start here."

Does Language Shape The Way We Think?

Do we humans all think in the same way, but express our thoughts differently depending upon which language we speak, or does the language we speak literally shape our thoughts? This interesting essay by Lera Boroditsky on EDGE aims to shed light on this perennial question and believes the latter is true. Particularly fascinating is her account on language and thought in the Kuuk Thayoore aborigines of northern Australia. Go to edge.org and scroll down to EDGE 289 for 12th June 2009.

Singing Mice Clue To Human Language

Chapter 2 of NOT A CHIMP tells the story of the discovery of the FOXP2 gene, how, early on it was erroneously dubbed "the language gene" and how research on a human family with speech and articulation difficulties, bolstered by work on the gene in chimps, singing birds, bats and mice, had led to a deeper understanding of its involvement in the coordination of the rapid sequential processes involved in the assembly of the components of language into speech and the complex articulation of the vocal tract to produce speech sounds. Now a team led by Polly Campbell at the University of Florida has extended this species comparison angle still further by comparing singing mice with lab. mice and deer mice. Interestingly, the pattern of expression of FOXP2 was remarkably similar across all species and while expression in the cerebellum and other structures involved in vocalisations was strong, they found a particularly high signature in the thalamus - a half-way house in the brain whereby signals from the sense organs and receptors in gut and skin etc. (the so-called somatosensory system) are relayed to the cortex for higher-order processing. So, FOXP2 has an even broader remit in the brain. Not only involved in vocal communication, but in sensorimotor integration in general. It seems that the evolution of human language, and the role of FOXP2 in it, continues to benefit from very wide range of species comparison. This is what happens when you take the "chimp-human" exclusive blinkers off.