Category: Science
Eating Apes
1. Bushmeat hunters in Africa typically earn in the range of $250 to $1050 a year.
2. In one sampled African market, ape meat cost about twice as much as beef or pork.
3. “In the big cities of Central Africa, it seems relatively easy to find a gorilla head or some hands, or perhaps a chimpanzee hand or two or four, for sale in the medicinal and fetish markets…In a Brazzaville fetish market, a dealer once offered me a gorilla head for the equivalent of $40 and a hand for about $10.”
4. Hunters of ape meat often rely on the trails cut by loggers
5. Ape meat supply has largely gone underground in recent years, although in a given market most people know whom to ask to get the meat.
6. Many village and hunter-gatherer societies have a special word for “meat-hunger.”
7. Central Africans eat at least as much meat per person as Americans or Europeans do.
8. Hunters claim that if a champanzee is wounded and cornered and about to meet his death, that he will beg for his life with the same expressions that a human being would use.
9. One hunter wrote: “It is this lurking reminiscence of humanity, indeed, which makes one of the chief ingredients of the hunter’s excitement in his attack of the gorilla.”
All of these bits are from Eating Apes, by Dale Peterson. This is a remarkably intelligent and disturbing book, the photos are unforgettable. The author is sympathetic to the plight of the great apes but he also understands how markets work, what the life of the poor is like, and why a naive ban on hunting is unlikely to succeed.
By the way, today’s Cnn.com reports that the Orangutan may be extinct within 10 to 20 years.
Neuroeconomics and trust
Today’s Financial Times runs a feature article on neuroeconomics, an offshoot of experimental economics.
Why do people cooperate in experimental games?
…during the games, Prof Smith’s team scanned players’ brains using functional magnetic resonance imaging. The FMRI scan showed that players who co-operated were using parts of their brain called Brodman’s areas 8 and 10. These areas had previously been associated with thinking about the mental activities and the motivations of others, and of delaying gratification to receive higher rewards later. Non-cooperative players did not use these parts of the brain, and neither did those who knew they were playing against computers instead of human opponents.
This, argues Prof Smith, is consistent with the reciprocity explanation: players are thinking about the likely responses of other players and deciding to trust them.
Brain scans are not the only tool of neuro-economists. Other approaches include measuring pulse rates, skin conductivity and hormone levels. And as a result of such experiments, neuroeconomics boasts an eclectic collection of findings – one of them being that ovulating women are less trustworthy than the rest of us…
Would you like to hear more about ovulating women?
Prof [Paul] Zak has also found that women who take part in the trust game while they are ovulating send back substantially less money to their fellow player than other women or than men – crudely, they are less trustworthy. He explains: “The physiological reason is that progesterone suppresses the effect of oxytocin. The evolutionary biological reason is that is that if you’re about to get pregnant, you should be very careful about overreacting to the social signals you receive. In addition, you don’t want to be giving away resources.” Prof Zak points out that since trust is fundamental to economic development, a better understanding of the oxytocin and the physiology of trust could be fundamental for promoting development. The Bangkok Post has already picked up on his work: the newspaper says that since the oxytocin stimulants massage, food and sex are much beloved of Thais, Thailand’s economic development is assured.
For those interested, GMU researcher Kevin McCabe has started a fledgling neuroeconomics blog.
A movie in your book
A piece of paper can now play video images:
A single sheet looks pretty much like ordinary paper. But the ink can be rearranged electronically fast enough to show video movies.
Its devisers, Robert Hayes and Johan Feenstra, have also figured out how to create full-colour displays. Their colour screens would be four times brighter than the flat devices currently made from liquid crystals, they reckon.
The invention is the latest version of ‘electronic ink’. Researchers hope to combine the convenience, robustness and readability of printed material with the vast and flexible information content of laptop computers.
In principle, a plastic sheet covered with electronic ink could display an entire library, page by page. The information would be stored in a portable chip, and the display would be powered by a slimline, lightweight battery. Harry Potter and the Order of the Phoenix would weigh no more than a feather.
Read more here from Nature magazine.
Brazil accepts genetically modified foods
The decision was made by a left-wing government, read Chris Mooney for some astute commentary. I have read a few books lately on genetically modified foodstuffs, Peter Pringle’s Food, Inc. was the most balanced. I’ve yet to see a case that the potential risks come close to outweighing the potential benefits. Remember the Green Revolution in agriculture? It saved millions of lives and elevated living standards around the world.
Tomorrow’s bathroom?
Trying to predict future technologies is as futile as it is fascinating. I was struck by the following bit from Bruce Sterling’s Tomorrow Now: Envisioning the Next Fifty Years:
You’re not made out of digital bits – like all living things, you are made mostly out of water. So that’s where you sensibly place your high-tech investments.
You don’t have a “shower stall.” You have a standard, everyday body-imaging system that gives you complete interior and exterior health scans every morning as it washes you. Your toothbrush scans the contents of your moth and catalogs its microorganisms. Your toilet is the most sophisticated network peripheral in the home. It provides you with vital metabolic information about your body – the substances that enter and leave it and the vital processes within it. Only fools are squeamish about this.
Here is an interview with Sterling about the book, he says: “I think the scenario is 70% muddle along, 15% do really great, 15% hit the skids big time.”
An even shorter introduction to intelligence
I recommend Ian Deary’s Intelligence: A Very Short Introduction. I am going to buy more books in this Oxford series. We at Marginal Revolution aim to provide value for attention, however, so here is an even shorter introduction.
1) Almost all measures of intelligence correlate with one another and quite a few measures of different aspects of intelligence are highly correlated. It is thus meaningful to talk about general intelligence, g. Howard Gardner’s work on “multiple intelligences” is on the fringes of scientific psychology.
2) Intelligence rankings are stable with age but fluid intelligence, meaning something like pure reasoning power, as opposed to crystalized intelligence peaks in the 20-30s and then declines with age.
3) Connecting IQ scores to brain morphology and activity is still in its infancy but there are modest, but well established, correlations between brain size and IQ (psychometric intelligence) and measures of reaction time (which plausibly measure brain speed) and IQ.
4) Intelligence is in large part genetic and that which is due to environment is primarily not due to the obvious possibilities such as family upbringing.
5) Intelligence matters for work performance and education. IQ is a better forecaster of work performance than just about any other test short of a trial run on the actual work to be performed.
6) IQ has been rising, the Flynn effect. No one knows why.
7) None of the above points are controversial among intelligence researchers.
Aside from Dreary’s book another useful introduction to intelligence research is the authoritative consensus report from the American Psychological Assocation, Intelligence: Knowns and Unknowns, summary here.
Herd behavior and dominant strategies for mice
Mice, taken collectively, are not very good at escaping from a crowded room. They act pretty much as humans do, namely they all crowd toward the door and few get out very quickly. Each individual mouse appears to make a rational calculation of a sort. The mice do best, and adopt some form of queuing behavior, when the door is large enough to let only one mouse through at a time. Researchers suggest that humans may exit a crowded more quickly, the smaller the door, which limits the crush toward the exit. For more information read this article from New Scientist.
Presidential Voices and Electoral Victory
A nice article in the Sept. 2002 Social Psychology Quarterly documents an interesting fact: the presidential candidate who has the right tone of voice tends to win the election.
According to “communication accommodation theory,” low status people change their voices to accommodate high status people. The presidential candidate who more frequently changes the “F_0” range of his voice (which is a very low hum) during a debate signals that he is in the low-status position. The authors believe that voters respond strongly to this non-verbal, but strongly emotional, cue. The authors note that George W. Bush may have “won” the 2000 debate with Gore because he signaled his dominance in this fashion, although Gore was perceived by journalists to have won through superior rhetoric. The results of voice analysis correlate well with electoral outcomes and polls.
Sleep and Personality
Sleep research is great fun. Sleep is tied to so much in our lives, yet we know so little and there are always surprises. Consider the latest finding: the position you sleep in is highly correlated to your social personality. Being a log-sleeper (on the side, hugging the pillow) correlates with being outgoing and social, while fetal position sleepers are shy. Sleeping position is not the only correlate of personality. Your handwriting, your job satisfaction and a whole bunch of other things tend to be linked to personality.
Things I had not known about taxonomy
The Swede Carl Linnaeus, a father of modern taxonomy, “spent much of his leisure time penning long and flattering portraits of himself, declaring that there had never “been a greater botanist or zoologist…””
Today the world has about 10,000 active taxonomists. It takes eight to ten years to train a good taxonomist. It is commonly believed that the world has a severe shortage of taxonomists, although economists might challenge the use of the word “shortage” in this context.
Logging a new species costs about $2000 per species.
Each year about fifteen thousand new species are recorded. Insects alone offer possibly as many as 100 million undiscovered species.
As of 2002, there were no full-time taxonomists in Africa.
Kevin Kelly’s (Wired magazine) All Species Foundation has not made much of a dent in these problems. And taxonomy is not nearly as web-based as you might think.
I don’t think it follows, as scientist Koen Maes suggests, that “It’s not a biodiversity crisis, it’s a taxonomist crisis!” Still, we know less about species and their numbers than I had thought.
All this is taken from Bill Bryson’s recent and entertaining A Short History of Nearly Everything, chapter 23. Thanks to Yesim Yilmaz for the pointer.
The best way to get a cell phone for use abroad
Very useful tips from Cronaca.com. It is cheaper than you think.
Monkey see, monkey do?
Monkeys appear to have an innate sense of when they are being treated unfairly, read here. Capuchin monkeys will refuse beneficial exchanges, if they see another monkey getting a better deal. Sound familiar? Similar results are found in the literature on experimental economics for humans, as Robert Frank notes at the link.
Here is one summary from The Washington Times, the only paper I can find in today’s Virginia power blackout, they don’t yet have the link on-line:
When both monkeys were given a cucumber slice after handing over the token, they completed the trade 95 percent of the time.
But when one was given the tastier grape for the same amount of work, the rate of cooperation from the other monkey fell to 60 percent…The refusal to make the exchange increased as the experiment continued…The scientists concluded that capuchins apparently measure rewards in relative terms…the tropical forest-dwelling capuchins were chosen for the experiment because they often share food.
One commentator on the study, a Charles Janson of SUNY, suggests that the behavior of the monkeys might have been learned in captivity (again, cited in The Washington Times).
Are cell phones killing off ghost stories?
Could ghost sightings be declining with the advent of cell phones? Will haunted houses lose their luster? The link is from the ever-excellent www.cronaca.com.
I can think of at least two explanations for this possible phenomenon. First, perhaps people with cell phones feel safer and hallucinate less. Second, perhaps it is harder to lie/self-delude right on the spot than afterwards, imagine telling your friend there is a ghost right next to you now. What if your friend asks to speak to it or hear it groaning? I also would like more data, how about alien abduction stories, noting that spaceships are presumably “dead zones.” My calling plan does not mention them…
The value of a lone dissenter
People will often abandon their opinions to conform to what a group expects of them, but a lone voice of reason can save the day. Cass Sunstein’s new book, Why Societies Need Dissent, reports the following (see chapter one):
You can give people a problem and allow them to solve it. Also give them a group of confederates, who unanimously advocate the wrong answer to the same problem. One confederate, proclaiming the wrong answer, will have little influence on the problem solver. Two confederates increased errors to 13.6 percent. Using three confederates increased errors to 31.8 percent. Under some results, more than three confederates do not increase the error rate, although this is controversial. But putting one voice of sanity in the group, who knows and proclaims the right answer, makes a big difference. “Conformity errors” were reduced by an average of three quarters, even if a strong majority of the group leaned the other way. Sunstein draws upon the work of Robert Baron, at the University of Iowa.
Medieval technology was better than you would think
The Australian BBC reports: “Medieval recipes for gunpowder produce nearly the same firepower as today’s manufactured equivalent, according to recent weapons tests, providing clues as to how the British fleet became one of the largest fighting forces in the world.” The full account is can be obtained through www.cronaca.com.