Recently Read: Not A Chimp by Jeremy Taylor

A nice review for the genetics part of not a chimp from genomics scientist Norman Johnson, with comments on cognition and behaviour from the book to come in later posts:

"As the title suggests, Jeremy Taylor's main thesis in Not a Chimp is that humans are not chimps and chimps are not humans, despite the apparent genetic similarity of these two primates. Taylor, who has had a long career in producing science documentaries, supports this claim from studies in two broad areas: genetics and behavior. In this first post, I'll discuss some of the genetic data. Later, I will cover the behavioral/psychological studies.

Taylor begins with some of the genes that differ between humans and chimpanzees and that show the signature of positive selection operating as these genes changed along the positive lineage. This is much-travelled ground; many books, including my own, have covered what we have learned about these genes. Still, Taylor brings new insight. For instance, consider the much-discussed FOXP2 gene. This gene, which has been touted by some as "the language gene", plays some role in language, speech, motor control, and possibly other aspects of cognition in humans. We know this based on studies of the KE family from the U. K., in which a mutation affecting those phenotypes is transmitted as an autosomal dominant allele. This gene has become of interest to evolutionary biologists because the amino acid of the protein it encodes has evolved more since humans diverged from chimpanzees than it has since primates diverged from rodents. Such a pattern, along with other evidence, strongly supports the hypothesis that positive selection has acted on this gene. But what does the gene do? Here's where Taylor shines. He presents the backstory showing the debates linguists, cognitive scientists, and others had during the 1980s and 1990s (long before we knew about the gene!) regarding the nature of the phenotypes affected by the mutation in the KE family. Taylor also does an important service reminding us that the mutation in the KE family is not one of the changes that have occurred at FOXP2 between humans and chimps.

In addition to the structural genes that differ between humans and chimps, we also differ in regulatory sequences. These regulatory sequences affect the expression (the amount of protein produced) of genes, both in space and in time. As Taylor presents, it turns out that we and chimpanzees differ substantially in gene expression. Such differences are most pronounced in the brain. We also differ - to a surprising extent- in the number of copies of genes that we have. Such copy number variation (CNV) is one of the major findings in human genomics in the past five years. Exactly how CNV affects phenotypes is still being worked out, but some cases are already known. For instance, CNV in specific genes affects susceptibility to progressing to full-blown AIDS after HIV exposure. The regulatory differences and CNV between humans and chimps shows that we are not as genetically similar to the other apes as we once thought we were.

Reference:

Taylor, J. Not a Chimp: The Hunt to Find the Genes that Make Us Human. Oxford University Press (2009)."

Battle of Ideas Debate on "Should Apes Have Rights/"

I was an invited speaker yesterday at a debate at the annual Battle of Ideas, run at the Royal College of Art in central London. Speaking against the motion I was aligned with Spiked editor Helene Guldberg whose book "Just Another Ape? has just come out, and Tipu Aziz, professor of neurosurgery at Oxford, who uses a lot of monkeys in his research to patent methods of direct electrode stimulation of the brain to cure Parkinsons. For the motion were veteran rights campaigner Richard Ryder - the man who coined the term "painism", and lawyer David Thomas. The debate was chaired by Stuart Derbyshire - a researcher, ironically, on pain, at the University of Birmingham.

I argued that recent cognitive psychology research suggests very strongly that humans are, as many of us of course suspect, genuinely exceptional with regards to what our minds can do - and far less genetically close to chimps than apes' rights campaigners would like us to believe. Ryder did not dispute that, but did dispute the idea that this gave us any reason to value ourselves more than the rest of the animal kingdom. His "painism" idea is a level playing field that requires us to extend rights to all creatures that we believe can feel pain. Both he and Thomas seemed at pains to suggest that they were not talking about rights in the law court, international statute sense of the word - but in a wider and more general sense of having interests that we should be aware of and protect. They were thus dodging the issue that "rights" in the hard legal sense is exactly what their colleagues in the Great Ape Project have been pursuing for apes in three legislatures recently - the government of the Balearics, New Zealand, and in the International Court of Human Rights in the Hague. Both Thomas and Ryder punted the old Peter SInger argument that tiny children or the very old - with Alzheimers disease - have rights even though they are incapable of fully understanding what they are - like chimpanzees - so why make an exception for humans? I have always found this attempt to equilibrate normal chimps with human elderly and mentally frail as particularly repugnant - doing no justice to either species - and it is also irrelevant because we know that infants will eventually grow into the fully functional adults that elderly people with Alzheimers disease once were. It seems to me that if you are going to talk about rights - flawed and often un-workable concept that it may be in human society - you have to talk about them in a legislative statute-book sense otherwise the whole debate lacks focus and what you are really talking about is "being nice to nature". And if you are talking about rights in the hard sense then obviously this is a farce with regard to non-human primates and other animals because they can have no concept of what a right is, cannot fight for them or defend them, and have no concept of the obligations to society that attends them.

Friendships Moderate an Association between a Dopamine Gene Variant and Political Ideology

In my chapter the ape that domesticated itself I strive toward a bio-social theory for humans and invoke recent work on a number of variants of prominent neuro-transmitters. These cases are prime examples of the subtle ways in which we are discovering that genes and the cultural environment interact to produce a number of behavioural phenotypes in human populations. I mention the 4R and 7R variants of the dopamine receptor at great length and in this fascinating paper the authors take these dopamine receptor variants into the realm of politics - specifically pointing out that a combination of the long 7R allele of DRD4 and a strong and functional circle of friends will produce a person with liberal tendencies. Heres the abstract:

"Scholars in many fields have long noted the importance of social context in the development of political ideology. Recent work suggests that political ideology also has a heritable component, but no specific gene variant or combination of variants associated with political ideology have so far been identified. Here, we hypothesize that individuals with a genetic predisposition toward seeking out new experiences will tend to be more liberal, but only if they are embedded in a social context that provides them with multiple points of view. Using data from the National Longitudinal Study of Adolescent Health, we test this hypothesis by investigating an association between self-reported political ideology and the 7R variant of the dopamine receptor D4 gene (DRD4), which has previously been associated with novelty seeking. Among those with DRD4-7R, we find that the number of friendships a person has in adolescence is significantly associated with liberal political ideology. Among those without the gene variant, there is no association. This is the first study to elaborate a specific gene-environment interaction that contributes to ideological self-identification, and it highlights the importance of incorporating both nature and nurture into the study of political preferences."

"Almost A Chimpanzee" Coming Soon

Interesting US book review for Jon Cohen's "Almost A Chimpanzee" which we should see on our UK Amazon in early December. Cohen's take on chimps and humans is entirely complementary to my own and, although there is inevitably significant overlap, it sounds as if its going to be a lively read. The last para of the review is telling - and I approve!

"The impossibility of a humanzee pleases Cohen, of course, who would rather us view chimps as very distant cousins. He tellingly quotes an American zookeeper, who told him, "Chimps are not imperfect human beings. They are perfect chimps."

Trouble In The Monkey House

A readable, if slightly confusing, article in the NY Times by Jennifer Schuessler, in which she conflates the downfall of comparative psychologist Marc Hauser, amid accusations of data-rigging, with a review of Sara Gruen's new novel "Ape House", and, much more pertinent to readers of this blog, the new book "Almost A Chimpanzee" by science writer Jon Cohen. Part of it revolves around the contrast between Gruen's starry-eyed interpretation of her meeting with "language competent" bonobos, and Cohen's more realistic account of their limitations as human linguists. Cohen's book is due to be published in the UK in December and, well-written, should prove to be entirely complementary to NOT A CHIMP, and Helene Guldberg's JUST ANOTHER APE? That worm is turning fast!

Serotonin selectively influences moral judgment and behavior through effects on harm aversion

In my chapter INSIDE THE BRAIN I look at the picture that is beginning to emerge of the way gene variants, the environment (particularly of childhood upbringing), and neurotransmitters affects our moral behaviour. I also deal with the way in which the moral decisions we make depend on the input of basic emotional signals like fear and disgust which are massaged into moral decisions by higher order parts of the brain's neo-cortex, especially the ventro-medial pre-frontal cortex (VMPC). An international team of scientists, lead author Molly Crockett from Cambridge, has just reported on the role of serotonin in these processes by its activity in these crucial components of the "social brain" - the amygdala, insula and VMPC. The abstract below tells you what you need to know and this paper is open access in PNAS.

"Aversive emotional reactions to real or imagined social harms infuse moral judgment and motivate prosocial behavior. Here, we show that the neurotransmitter serotonin directly alters both moral judgment and behavior through increasing subjects’ aversion to personally harming others. We enhanced serotonin in healthy volunteers with citalopram (a selective serotonin reuptake inhibitor) and contrasted its effects with both a pharmacological control treatment and a placebo on tests of moral judgment and behavior. We measured the drugs' effects on moral judgment in a set of moral 'dilemmas' pitting utilitarian outcomes (e.g., saving five lives) against highly aversive harmful actions (e.g., killing an innocent person). Enhancing serotonin made subjects more likely to judge harmful actions as forbidden, but only in cases where harms were emotionally salient. This harm-avoidant bias after citalopram was also evident in behavior during the ultimatum game, in which subjects decide to accept or reject fair or unfair monetary offers from another player. Rejecting unfair offers enforces a fairness norm but also harms the other player financially. Enhancing serotonin made subjects less likely to reject unfair offers. Furthermore, the prosocial effects of citalopram varied as a function of trait empathy. Individuals high in trait empathy showed stronger effects of citalopram on moral judgment and behavior than individuals low in trait empathy. Together, these findings provide unique evidence that serotonin could promote prosocial behavior by enhancing harm aversion, a prosocial sentiment that directly affects both moral judgment and moral behavior."

Can Rhesus Macaques Pass The Mirror Test?

Some 40 or more years ago, American psychologist Gordon Gallup came up with a mirror test for self-awareness that could be applied across a whole range of species. In the classic versions of the experiment, primates, say, were anaethetised before a small dab of red dye was placed on their forehead. Measurements were then taken, on recovery, to compare their behaviour with their reflections in a mirror. A greater incidence of movements of hands to forehead to investigate the area around the spot suggested to researchers that the animals concerned had some concept of self-awareness - "Look that's me!" Higher primates like chimps could pass the test, as has one elephant to date. But, so far, no monkeys have ever demonstrated they can pass the mirror test. If the test really did test for self-awareness, any animal which passed it would have dissolved one major cognitive barrier between humans and the rest of the animal kingdom, however, the test has always been criticized because not all researchers are convinced that body awareness is the same as self-awareness. That there is a difference between examination of one's body and a deeper sense of knowledge of oneself as a psychological entity with inner mental states. This "The Scientist" piece comments on some recent work reported in PLoS 1 where rhesus monkeys are held to have passed the mirror test for the first time. Instead of having red blobs of paint on their heads, these monkeys had already been implanted with electronic terminals for experimentation. Would they react to the sight of the terminals in a mirror? Although they did indeed react as if to satisfy the test, the experiment has drawn criticism, including some from the originator of the original test - Gordon Gallup. Gallup says this experiment is un-interpretable because the monkeys could feel the implant as well as see it - whereas , in his test, this was controlled for because the only way the monkeys could be aware of the paint mark was by seeing it. SO, for the time being, for several reasons the question of whether or not monkeys have any self-awareness remains open.

Since PLoS is a free journal here is the url for the original paper - in case anyone wants to follow it up.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0012865