Social capital formation in rats

[...] we show experimentally that cooperative behavior of female rats is influenced by prior receipt of help, irrespective of the identity of the partner. Rats that were trained in an instrumental cooperative task (pulling a stick in order to produce food for a partner) pulled more often for an unknown partner after they were helped than if they had not received help before.

The paper, published in PLoS Biology, is free to access. With the exception of direct reciprocity (the 'you've been nice to me, I'll be nice to you' type), no other mechanism for reciprocity had ever been demonstrated in nonhuman animals before.

'Altruistic behavior by previous social experience irrespective of partner identity' is fundamental to human society, and perhaps the single behaviour economic theory most struggles with.

Best argument for creationism, ever

No, not this one. This reminds me too much of celestial teapots and the fact that a strong prior will get you anywhere (and you can't have science without priors). Thucydides would have been appalled by this sophistry. I'm talking about this one:

The materialist explanation of the creation has nothing to offer - if we came from nothing and go into nothing, then that encourages people to lead reckless and materialistic lifestyles.

Evolution is a world-view that leads to futility. It's no wonder people are dissatisfied with it.

We have no reason to accept knowledge that disatisfies us. You should believe what pleases you.

Just don't try this with gravity.

What happens when we die?

A number of recent scientific studies carried out by independent researchers have demonstrated that 10-20 per cent of people who go through cardiac arrest and clinical death report lucid, well structured thought processes, reasoning, memories and sometimes detailed recall of events during their encounter with death.

Here is more on the World's Largest-Ever Study of Near Death Experiences. This is interesting stuff:

“Contrary to popular perception,” Dr Parnia explains, “death is not a specific moment. It is a process that begins when the heart stops beating, the lungs stop working and the brain ceases functioning – a medical condition termed cardiac arrest, which from a biological viewpoint is synonymous with clinical death.

“During a cardiac arrest, all three criteria of death are present. There then follows a period of time, which may last from a few seconds to an hour or more, in which emergency medical efforts may succeed in restarting the heart and reversing the dying process. What people experience during this period of cardiac arrest provides a unique window of understanding into what we are all likely to experience during the dying process.”

During the AWARE study, doctors will use sophisticated technology to study the brain and consciousness during cardiac arrest. At the same time, they will test the validity of out of body experiences and claims of being able to ‘see’ and ‘hear’ during cardiac arrest.

Something you should know

Living on a farm during pregnancy may help reduce the chance of the child developing asthma, eczema and even hayfever, say scientists.

Friday Special 49

Global warming is by far an absolute truth as illustrated by a DailyTech article

The heart of the award-winning hybrid Toyota Prius: Power Split Device

Google's environmental efforts with their Solar Panel project

On the 53 major events in A Briefer History of Time (PDF)

Creepy girl from MotionPortrait

An economist's dad

Levitt is a veritable gas guru, a leading expert on the underappreciated field of flatus -- intestinal gas that escapes via the southern route. He admits his unusual expertise has put his three kids (one of whom is economist and "Freakonomics" co-author Steven Levitt) through expensive universities.

The article, which covers a lot of scientific knowledge on flatulence, is fun to read. I found the experiment on the potency of male vs female gases fascinating, if somewhat disturbing.

And playing amateur psychologist here, maybe it's precisely this background that gave young Steven the idea of pursuing unusual - 'freaky' - subjects in his own discipline, and most readers of this blog know all about that.

HT Odd Numbers.

Our solar system

A reader emailed me these fascinating pictures:


And the big boy:

Assume blacks have lower IQ than whites and DNA is to blame

Now name one thing you would do differently - as a politician, as a citizen or as a human being. I'll be damned if you can come up with a single example.

I really, really can't understand what this debate is all about (other than in an immature 'I did not evolve from the apes' or 'I am really frustrated the earth is not at the centre of the solar system' kind of a way). Hell, even this debate is more relevant.

Now can we please, as a culture, move on?

Sex of a child may depend on stress

From the Economist (November 15, 2007)

A Boy or a girl? That is usually the first question asked when a woman gives birth. Remarkably, the answer varies with where the mother lives. In rich countries the chances of its being a boy are about 5% higher than in poor ones.

Strange as it might seem, the terrorist attacks of September 11th 2001 shed light on the enigma. Studies noting the sex of babies conceived in New York during the week of the attacks found a drop in the ratio of males to females. That is consistent with earlier studies, which revealed a similar shift in women who became pregnant during floods and earthquakes and in time of war.

Dr Obel suspects the immediate cause is that male pregnancies are more likely to miscarry in response to stress than female pregnancies are, especially during the first three months.

While there are many factors that could potentially influence the gender of a child, the most accurate tool may after all be the ancient Chinese birth chart.

Science reporting explained

Via Social Science Statistics. The Dilbert blog is, of course, by far the best economics blog amongst nominally-non-economics blogs out there.

Plagiarism, of a cute nature

Scott Aaronson has a money-can't-buy experience:

A reader named Warren Smith informs me of an Australian TV commercial (which you can watch on YouTube), in which two fashion models have the following conversation:

Model 1: But if quantum mechanics isn’t physics in the usual sense — if it’s not about matter, or energy, or waves — then what is it about?

Model 2: Well, from my perspective, it’s about information, probabilities, and observables, and how they relate to each other.

Model 1: That’s interesting!

The commercial then flashes the tagline “A more intelligent model,” followed by a picture of a Ricoh printer.

More intelligent, or simply more shameless? Ladies and gentlemen of the jury, allow me to quote from Lecture 9 of my Quantum Computing Since Democritus notes:

But if quantum mechanics isn’t physics in the usual sense — if it’s not about matter, or energy, or waves, or particles — then what is it about? From my perspective, it’s about information and probabilities and observables, and how they relate to each other.

Postscript: Responding to his (many, many) comments, Scott stumbles upon two fundamental truths that many a blogger will relate to:

The longer I blog, the more I despair of ever achieving my central goal in life, namely for everyone to like me.

The longer I blog, the more I despair of ever achieving my secondary goal in life, namely for everyone to understand me.

Appendix not useless after all

Scientists at Duke University Medical School believe it acts as a 'good safe house for bacteria', and while not needed in a modern industrialised society, it may still carry out a useful function in some developing countries.

HT Newmark's door.

Evolutionary psychology and hunting berries

I want you to know that I love evolutionary psychologists, because the ideas, like “girls prefer pink because they need to be better at hunting berries” are so much fun. Sure there are problems, like, we don’t know a lot about life in the pleistocene period through which humans evolved; their claims sound a bit like “just so” stories, relying on their own internal, circular logic; the existing evidence for genetic influence on behaviour, emotion, and cognition, is coarse; they only pick the behaviours which they think they can explain while leaving the rest; and they get themselves in massive trouble as soon as they go beyond examining broad categories of human behaviors across societies and cultures, becoming crassly ethnocentric. But that doesn’t stop me enjoying their ideas.

This is Ben Goldacre, saying it beautifully. He's not making the berries thing up. Read the whole thing.