For scientifically minded fans of The Pedal-to-the-Metal, Totally Illegal, Cross-Country Sprint for Glory.

Having caught, by chance, the broadcast of a multi-car NASCAR crash on television, Nebraska University physics professor Diandra Leslie-Pelecky found herself compelled to understand why it happened. Soon, a growing list of scientific questions ("How do you build an engine...that can run at 9,000 rpm for three hours without blowing up?") steer her to meetings with engineers, ground crews and drivers who work together "at the limits of what we understand about aerodynamics, structural engineering and even human physiology." The first part of the book deals with materials, and looks at how combustion, power and aerodynamics work together to maximize speed. But it's the driver and his crew who win the race, and Leslie-Pelecky gets plenty of time with the men behind the machines, joining Ray Evernham's crew to watch him race, and taking a turn behind the wheel herself. Along the way, the nanotech specialist becomes an unlikely racing fan; this fun physics primer should give any NASCAR aficionado a similar appreciation for science.

See also the companion web site, Stock Car Science, or check out the book blog (only a week old, though).

The Physics of NASCAR: How to Make Steel + Gas + Rubber = Speed

Truth be told, Barash's line of inquiry, like Richard Dawkins' or Steven Pinker's, does result in bracing and unsettling ideas. Through the lens of evolutionary psychology, we are forced to face our ancient self, that bestial creature that knows nothing of atomic bombs or jihad, marriage or MySpace, but still haunts our body, fuels our emotions and rules our lives — our genetic identity. For this single-minded creature, monogamy is a myth, free will is doubtful, and so-called altruism is merely a misguided attempt to protect people who might be carrying our genes. (Since humans once lived in small, closely related packs, protecting others made genetic sense.) In a recent article for The Chronicle of Higher Education, Barash wrote about how electrocuted rats develop ulcers and swollen adrenal glands unless they are allowed to fight other "innocent" rats. In short: Random acts of violence are never actually random; we are merely obeying a million-year-old code of behavior, a code of displaced aggression that Barash finds in The Iliad, in Sweeney Todd and in our current war in Iraq. Barash's latest book, Natural Selections, published by Bellevue Literary Press (a small press run out of the oldest public hospital in the United States, Bellevue in Manhattan), seeks to follow the concepts of evolutionary psychology and sociobiology to their logical conclusions. "Many people claim to accept the tenets of evolution," he says, "but few actually look at where these premises lead."

I talked with Barash by phone about his book, his science and his philosophy.

Tyranny of the Natural: David P. Barash's Natural Selections

Having a large network of friends and family, a new study suggests, may help surgical patients experience less anxiety and pain before their operations and a quicker recovery afterward.

Prognosis: Large Social Networks May Help Surgical Patients

Practitioners, however, have another purpose. They wish to know how to make their patients better. But until we can organize a compendium of mental illnesses according to a better working knowledge of the brain, the therapeutic revolution in psychiatry will have to wait. Neuroscientists and psychiatrists have certainly made prodigious strides -- and yet we are far from grasping how those swirling galaxies of neurons and molecules make us who we are, both in sickness and in mental health. Even as we gather light, we are still struggling in the dark.

From the archive:

A recent poll conducted by the Pew Research Center shows that almost 85 percent of Americans believe that they are very happy or at least pretty happy.

What drives this rage for complacency, this desperate contentment?

Are some people lying, or are they simply afraid to be honest in a culture in which the status quo is nothing short of manic bliss?

The Loss of Sadness: How Psychiatry Transformed Normal Sorrow Into Depressive Disorder

Broiler (meat) chickens have been subjected to intense genetic selection. In the past 50 years, broiler growth rates have increased by over 300% (from 25 g per day to 100 g per day). There is growing societal concern that many broiler chickens have impaired locomotion or are even unable to walk. Here we present the results of a comprehensive survey of commercial flocks which quantifies the risk factors for poor locomotion in broiler chickens. We assessed the walking ability of 51,000 birds, representing 4.8 million birds within 176 flocks. We also obtained information on approximately 150 different management factors associated with each flock. At a mean age of 40 days, over 27.6% of birds in our study showed poor locomotion and 3.3% were almost unable to walk. The high prevalence of poor locomotion occurred despite culling policies designed to remove severely lame birds from flocks. We show that the primary risk factors associated with impaired locomotion and poor leg health are those specifically associated with rate of growth. Factors significantly associated with high gait score included the age of the bird (older birds), visit (second visit to same flock), bird genotype, not feeding whole wheat, a shorter dark period during the day, higher stocking density at the time of assessment, no use of antibiotic, and the use of intact feed pellets. The welfare implications are profound. Worldwide approximately 2x10^10 broilers are reared within similar husbandry systems. We identify a range of management factors that could be altered to reduce leg health problems, but implementation of these changes would be likely to reduce growth rate and production. A debate on the sustainability of current practice in the production of this important food source is required.

Leg Disorders in Broiler Chickens: Prevalence, Risk Factors and Prevention

The success of "The Dangerous Book for Boys" — which has been on the best-seller list for the last nine months — and its step-by-step instructions for activities like folding paper airplanes is testament to the generalized longing for play’s good old days. So were the questions after Stuart Brown’s library talk; one woman asked how her children will learn trust, empathy and social skills when their most frequent playing is done online. Brown told her that while video games do have some play value, a true sense of "interpersonal nuance" can be achieved only by a child who is engaging all five senses by playing in the three-dimensional world.

This is part of a larger conversation Americans are having about play. Parents bobble between a nostalgia-infused yearning for their children to play and fear that time spent playing is time lost to more practical pursuits. Alarming headlines about U.S. students falling behind other countries in science and math, combined with the ever-more-intense competition to get kids into college, make parents rush to sign up their children for piano lessons and test-prep courses instead of just leaving them to improvise on their own; playtime versus résumé building.

Discussions about play force us to reckon with our underlying ideas about childhood, sex differences, creativity and success. Do boys play differently than girls? Are children being damaged by staring at computer screens and video games? Are they missing something when fantasy play is populated with characters from Hollywood’s imagination and not their own? Most of these issues are too vast to be addressed by a single field of study (let alone a magazine article). But the growing science of play does have much to add to the conversation.

Taking Play Seriously

Po Bronson, in New York Magazine:

Kids lie early, often, and for all sorts of reasons -- to avoid punishment, to bond with friends, to gain a sense of control. But now there’s a singular theory for one way this habit develops: They are just copying their parents.

Learning to Lie

New cameras don't just capture photons; they compute pictures.

The digital camera has brought a revolutionary shift in the nature of photography, sweeping aside more than 150 years of technology based on the weird and wonderful photochemistry of silver halide crystals. Curiously, though, the camera itself has come through this transformation with remarkably little change. A digital camera has a silicon sensor where the film used to go, and there's a new display screen on the back, but the lens and shutter and the rest of the optical system work just as they always have, and so do most of the controls. The images that come out of the camera also look much the same—at least until you examine them microscopically.

But further changes in the art and science of photography may be coming soon. Imaging laboratories are experimenting with cameras that don't merely digitize an image but also perform extensive computations on the image data. Some of the experiments seek to improve or augment current photographic practices, for example by boosting the dynamic range of an image (preserving detail in both the brightest and dimmest areas) or by increasing the depth of field (so that both near and far objects remain in focus). Other innovations would give the photographer control over factors such as motion blur. And the wildest ideas challenge the very notion of the photograph as a realistic representation. Future cameras might allow a photographer to record a scene and then alter the lighting or shift the point of view, or even insert fictitious objects. Or a camera might have a setting that would cause it to render images in the style of watercolors or pen-and-ink drawings.

Computational Photography

Tuning one's shower in some hotels may turn into a challenging coordination game with imperfect information. The temperature sensitivity increases with the number of agents, making the problem possibly unlearnable. Because there is in practice a finite number of possible tap positions, identical agents are unlikely to reach even approximately their favorite water temperature. Heterogeneity allows some agents to reach much better temperatures, at the cost of higher risk.

Taking a shower in Youth Hostels: risks and delights of heterogeneity

To understand consciousness and its evolution, we need to ask the right questions.

Questioning Consciousness