Book review: Monkeyluv: And Other Essays on Our Lives as Animals by Robert M. Sapolsky.
This collection of essays starts out by rehashing nature/nurture arguments that ought to be widely understood by now, but then becomes mostly entertaining and occasionally quite informative.
He mentions one interesting study which questions sexual selection arguments put forward by Geoffrey Miller and others about animals selecting mates with better genes. The study shows that female Mallards produce stronger offspring after mating with more attractive males because they invest more resources in those eggs, rather than because of anything that seems connected to the genes provided by the males.
He helps explain the attraction of gambling by describing experiments which show larger dopamine releases due to rewards that are most uncertain (the subject thinks they have a 50% chance of happening) than is released when there’s more certainty (e.g. either a 25% chance or a 75% chance) of the same reward.
One place where I was disappointed was when he described “repressive personalities”, which he made seem quite similar to Aspergers, and made me wonder whether I fit his description. “dislike novelty”? My reaction to novelty is sufficiently context-dependent that any answer is plausible. “prefer structure and predictability”? Yes and usually. “poor at expressing emotions or at reading the nuances of emotions in other people”? That’s me. “can tell you what they’re having for dinner two weeks from Thursday”? I could probably predict 5 days in advance with 50% accuracy, so I’m probably closer than most people. So I Googled and found another description (mentioning the same researcher that Sapolsky mentioned) in the Sciences and find descriptions of “repressive personality” that seem wildly different from me (“a strong personal need for social conformity” and “agreement with statements framed as absolutes, statements loaded with the words never and always”). Who wrote this competing description? Wait, it’s the same Sapolsky! It looks like his current description reuses a small piece of an older article with inadequate thought to whether it’s complete enough.
Book review: No Two Alike: Human Nature and Human Individuality by Judith Rich Harris
This book provides a clear theory of what causes the personality differences between people that can’t be explained by genetic differences. She focuses a fair amount on identical twins, because the evidence that their environmentally caused personality differences are the same as ordinary siblings, and the same whether they’re reared together or apart, rules out many tempting theories.
Amazon reviewer Sioran points out an inconsistency – she claims early on that random chance can’t explain all of the variation, but her explanation ends up amounts to saying the causes are ultimately random. I find her early arguments against randomness unconvincing. And her explanation’s reliance on randomness doesn’t imply that her explanation is useless – she rules out most kinds of randomness as a cause, narrowing down the class of random causes to those which affect the person’s view of her status in society (e.g. differences in who outside family the person interacts with, and physical differences such as being tall due to better nutrition).
The most surprising prediction she makes is that mindblind (i.e. most) animals won’t have persistent personality differences that can’t be explained by genetic differences. I’m unsure whether to believe this – it seems that animals should only need to remember differences in how others treat them (rather than have a theory of mind) in order to produce the results we see. She would probably predict that autistic people have no persistent environmentally caused personality differences, but she isn’t clear about that (it may depend on the degree of autism).
One interesting result that she mentions is that autistic children are unable to use the fusiform face area (which in most people is specialized to do good face recognition), and instead seem to recognize faces the same way they recognize ordinary objects. I’m wondering how much this explains about why autism impairs many parts of the mind that deal with relationships.
I’m annoyed by how many pages she spends recounting the reaction to her prior book (The Nurture Assumption, a better book than this). If you’ve read that, most of the first half of this book will be a waste of time.
One interesting piece of evidence she mentions is this paper from the Journal of Political Economy which says that one’s height as a teenager is a better predictor of wages as an adult than adult height.
One small quibble: she says being a firstborn is unimportant (often not even known) outside the home in “contemporary societies — at least those not ruled by monarchies”. Korean society appears to be a clear exception to that claim.
The conference on Human Enhancement Technologies and Human Rights this past weekend had many boring parts and a few interesting tidbits.
Many of the speakers were left-wing ideologues who seemed to be directing their speeches only to others from the same small set of left-wing academics. There were fewer libertarians at the conference than I expected, but still enough that it was strange how much of a disconnect there was between the ideology shown in the speeches and the ideology I knew from elsewhere that many people held but were being quiet about.
There was plenty of concern about whether increased control over one’s body would decrease diversity, but I heard little that enlightened me on that subject. There have clearly been many technologies that increased diversity, such as tattoos. There are some that have decreased diversity because there is a substantial consensus about what’s best (e.g. eyesight – it’s unclear why we should be concerned about a shortage of people who can’t see well enough to drive). Then there are a few traits such as degree of autism where there’s some uncertainty whether reduced diversity would be good. There are some pontificators (I didn’t hear anyone this focused at the conference) who think they know better than the masses what the right amount of diversity is, and that their opinions should be imposed on the masses. But the evidence for the pontificators’ expertise and the masses propensity to make mistakes is generally underwhelming, so I can’t find much reason to be as concerned about the effects of enhancement technology as I am about the desire to impose expert opinion on those who don’t want it.
Hank Greely pointed out that the letter of the law authorizes the FDA to regulate anything that could be considered a body enhancement, including clothing. So only the FDA’s interest in obeying the spirit of the law will deter them from regulating external enhancements.
One amusing report of unwanted side effects of an enhancement technology is the increase in sexually transmitted diseases in seniors following the introduction of Viagra.
Aubrey de Grey made an interesting argument that the most effective approach to convincing people to support a cure for aging is to persuade them that they are being logically inconsistent when they fail to do so. He has a point, but it’s weaker than he thinks. He gave several examples of problems that were allegedly solved by persuading society to be more logically consistent, but I generally doubt that’s what happened. One example was tolerance of homosexuality. I see few signs that logical arguments had much effect on that. I think the biggest change came from peer pressure, which became increasingly popular as gays became able to migrate to places where there were enough gays to safely start exerting peer pressure. Another factor was the shift away from the belief that the main purpose of sex should be reproduction. That initially happened due to changing circumstances (reduced reliance on children to support elderly parents). I’d say that has generally produced beliefs that are more inconsistent as people abandon the least convenient symptoms of the belief (e.g. contraception) but are much slower to abandon symptoms that are remote from their experience. I think similar theories could be made about some other examples he gave (slavery becoming more expensive to enforce when railroads made it easier for slaves to escape to a non-slave state).
Temple Grandin’s latest book Animals in Translation has a couple of ideas that deserve some wider discussion. (The book as a whole is disappointing – see my reviews on Amazon for some of my complaints).
She reports that Con Slobodchikoff has shown that prairie dogs have a language that includes nouns, adjectives, and verbs, and they can apparently combine words to describe objects they haven’t seen before. This seems sufficiently inconsistent with what I’ve read about nonhuman languages (e.g. in Pinker’s books) that it deserves more attention than it has gotten. I can’t find enough about it on the web to decide whether to believe it, and it will take some time for me to get a paper version of Slobodchikoff’s descriptions of the research.
Grandin has an interesting idea about the coevolution of man and dogs. Domestication of animals causes their brains to become smaller, presumably because they come to rely on humans for some functions that they previously needed to handle themselves. It seems that human midbrains shrank about 10% around 10,000 years ago, about when dogs may have become domesticated. That is what we would expect if humans came to rely on dogs for many smelling tasks.
Science Blog has an interesting article on the effects of autism which helps to explain why it’s not an accident that autism has both advantages and disadvantages.