Uncategorized

The evolutionary fitness of dancing?

Beth Kelley

There is some interesting about how dance is indicative of physical health and fertility, but I particularly loved Chris Hampson’s take on some new research about why older guys dance poorly.

It is one of the mysteries of life, then, that such dexterity and skill ultimately, and invariably, leads to a phenomenon widely known as Dad Dancing. 
Sadly, you’ve all seen it.
Grown men who should know better hog the dance-floor at wedding receptions and indulge in cringe-worthy, awful antics that make other adults shrink away, and children wish they had eloped.
It is worse than those school pick-up moments when some spotty, gangling teenage child you have rushed to collect asks you to wait in the car because your very existence embarrasses them.

Dad Dancing is our revenge.

Explanation? Evolution
But now an academic in the U.K. has come up with another explanation. Evolution.

It seems that middle-aged wannabe “John Travolta dancing” is nature’s way of warning lovely and nubile young women to look elsewhere. Who knew?
It is, according to Dr. Peter Lovatt, the psychologist behind the study, a way of sending out a message: “Stay Away. I’m not fertile.” They then hurry off to look for a young man who is at his sexual peak, so they can have babies and save the species. 
Dad Dancing is, it seems, like fly spray – a repellant intended to kill off any sexual desire. 
Why you would need an academic study to tell you that I don’t know. I have yet to hear of any lovely 18-year-olds who long to dally with middle-aged, balding, boring men who are several years older than their dad.
Lovatt has apparently compared the dancing styles and confidence levels of nearly 14,000 people – more even than the judges on Dancing with the Stars. (Where did he find the time?) It seems that men between 35 and their 60s typically attempt complex dance moves with limited co-ordination. Women gauge the males’ testosterone levels by assessing the style and energy of their moves.

Then, according to this theory, they apparently make a dash for the nearest Boy Scout camp.

In a somewhat unflattering comparison, Lovatt explains: “It’s like an apple that’s going brown – you want a fresh green one instead.”

A brown apple? Me?

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Uncategorized

Beauty is only city-deep

Beth Kelley

From MSNBC (with a few edits because I can’t help myself):

Women’s magazines often spread the same message: Money may not buy you happiness, but beauty certainly will. A new study has actually proven that the women’s magazines were right — so long as you live in the city. But if you’re a country girl, it’s more of a case of “pretty is as pretty does.”
Researchers have found that happiness for city women is quite dependent upon physical appearance. But in the country, looks don’t count for much in terms of overall life satisfaction and happiness, according to a new study in the journal Personal Relationships.
 
“City women who were the most attractive got a lot of bang for their appearance buck,” says the study’s lead author, Victoria Plaut, a visiting assistant professor of psychology at the University of California, Berkeley, School of Law, and an assistant professor at the University of Georgia. “And if you were even slightly below average, you were very clearly worse off.”
When it came to women living in the country, there was no connection between physical appearance and happiness. Even more interesting — there was a slight trend in the data for women in the country to be happier if they were chubbier, Plaut says.
For the new study, Plaut and her colleagues interviewed 257 women who lived in the city and 330 from the country. The women were asked to rate their satisfaction with life, their connectedness with friends and community, and their general level of happiness. For a measure of satisfaction, they were asked to rate their lives on a scale of 1 to 10, with 1 being “worst possible life you can imagine” and 10 listed as the “best possible life you can imagine.”
To get a sense of the women’s attractiveness, researchers asked for waist and hip measurements. Other studies have shown that the ratio of waist to hips is a reliable indicator of attractiveness, Plaut explains. The lower the ratio, the slimmer the waist — and the more attractive a woman is considered to be.
The new findings fall in line with other research, says Michael Cunningham, a psychologist and professor in the department of communications at the University of Louisville, Ky. “In competitive and individualistic cultures you have to compete for limited social attention,” Cunningham says. “Physical attractiveness is one of the variables that gets you social attention and other positive outcomes. But in communal cultures and rural areas, family reputation and other longer-term variables have a bigger impact on your well-being. As a consequence, physical attractiveness doesn’t have as big an impact.” 
I’m not sure yet if I buy Cunningham’s reasoning why this is true; I think it’s more complicated than competition for attention. But I’d love to hear what other people think.
 Read the full article
brain

ADHD brains: taking the long way home

Beth Kelley

This idea that ADHD brains are simply delayed development, not “deviant” development, has been for the most part sort of speculative before, so I’m glad someone has started studying this more thoroughly. Re-posted from Not Exactly Rocket Science:

Attention-deficit hyperactivity disorder is the most common developmental disorder in children, affecting anywhere between 3-5% of the world’s school-going population. As the name suggests, kids with ADHD are hyperactive and easily distracted; they are also forgetful and find it difficult to control their own impulses.
While some evidence has suggested that ADHD brains develop in fundamentally different ways to typical ones, other results have argued that they are just the result of a delay in the normal timetable for development.
Now, Philip Shaw, Judith Rapaport and others from the National Institute of Mental Health have found new evidence to support the second theory. When some parts of the brain stick to their normal timetable for development, while others lag behind, ADHD is the result.
The idea isn’t new; earlier studies have found that children with ADHD have similar brain activity to slightly younger children without the condition. Rapaport’s own group had previously found that the brain’s four lobes developed in very much the same way, regardless of whether children had ADHD or not.
But looking at the size of entire lobes is a blunt measure that, at best, provides a rough overview. To get an sharper picture, they used magnetic resonance imaging to measure the brains of 447 children of different ages, often at more than one point in time.
At over 40,000 parts of the brain, they noted the thickness of the child’s cerebral cortex, the brain’s outer layer, where its most complex functions like memory, language and consciousness are thought to lie. Half of the children had ADHD and using these measurements, Shaw could work out how their cortex differed from typical children as they grew up.
A child grows, their experiences manifest as connections between nerve cells and their cortex thickens. But during adolescence, the developing brain values efficiency over expansion and the cortex starts to thin, as unused connections are mercilessly trimmed. The growth of a child’s brain into a teenager’s is like the pouring of a block of clay that can then be sculpted away into the refined adult version.
In both groups of children, parts of the cortex peaked in terms of thickness in the same order, with waves of maturity spreading from the edges to the centre. The pattern was the same, but the timing wasn’t.

Reference:Shaw, P., Eckstrand, K., Sharp, W., Blumenthal, J., Lerch, J., Greenstein, D., Clasen, L., Evans, A., Giedd, J., & Rapoport, J. (2007). From the Cover: Attention-deficit/hyperactivity disorder is characterized by a delay in cortical maturation Proceedings of the National Academy of Sciences, 104 (49), 19649-19654 DOI: 10.1073/pnas.0707741104

behavior

Tool use in the octopus

Beth Kelley

The title of this post almost rhymes. But that’s not important – what IS is the fact that we’ve found yet another animal that uses tools. Huzzah!

I’m using Science Daily‘s article:

Scientists once thought of tool use as a defining feature of humans. That’s until examples of tool use came in from other primates, along with birds and an array of other mammals. Now, a report in the December 14th issue of Current Biology, adds an octopus to the growing list of tool users.

The veined octopus under study manages a behavioral trick that the researchers call stilt walking. In it, the soft-bodied octopus spreads itself over stacked, upright coconut shell “bowls,” makes its eight arms rigid, and raises the whole assembly to amble on eight “stilts” across the seafloor. The only benefit to the octopus’s ungainly maneuver is to use the shells later as a shelter or lair, and that’s what makes it wholly different from a hermit crab using the discarded shell of a snail.

“There is a fundamental difference between picking up a nearby object and putting it over your head as protection versus collecting, arranging, transporting (awkwardly), and assembling portable armor as required,” said Mark Norman of the Museum Victoria in Australia.

Julian Finn, also of the Museum Victoria, said the initial discovery was completely serendipitous.
“While I have observed and videoed octopuses hiding in shells many times, I never expected to find an octopus that stacks multiple coconut shells and jogs across the seafloor carrying them,” he said.
In recalling the first time that he saw this behavior, Finn added, “I could tell that the octopus, busy manipulating coconut shells, was up to something, but I never expected it would pick up the stacked shells and run away. It was an extremely comical sight — I have never laughed so hard underwater.”

After 500 diver hours spent “under the sea,” the researchers observed the behavior of 20 veined octopuses. On four occasions, individuals traveled over considerable distances — up to 20 meters — while carrying stacked coconut shell halves beneath their body.

“Ultimately, the collection and use of objects by animals is likely to form a continuum stretching from insects to primates, with the definition of tools providing a perpetual opportunity for debate,” the researchers concluded. “However, the discovery of this octopus tiptoeing across the sea floor with its prized coconut shells suggests that even marine invertebrates engage in behaviors that we once thought the preserve of humans.”

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music · neuroscience

Listen with your skin

Beth Kelley2 Comments

That’s right. We humans listen to music with our skin!

Totally stolen from Not Exactly Rocket Science:

What part of the body do you listen with? The ear is the obvious answer, but it’s only part of the story – your skin is also involved. When we listen to someone else speaking, our brain combines the sounds that our ears pick up with the sight of the speaker’s lips and face, and subtle changes in air movements over our skin. Only by melding our senses of hearing, vision and touch do we get a full impression of what we’re listening to. 
When we speak, many of the sounds we make (such as the English “p” or “t”) involve small puffs of air. These are known as “aspirations”. We can’t hear them, but they can greatly affect the sounds we perceive. For example, syllables like “ba” and “da” are simply versions of “pa” and “ta” without the aspirated puffs. 
If you looked at the airflow produced by a puff, you’d see a distinctive pattern – a burst of high pressure at the start, followed by a short round of turbulence. This pressure signature is readily detected by our skin, and it can be easily faked by clever researchers like Bryan Gick and Donald Derrick from the University of British Columbia.
Gick and Derrick used an air compressor to blow small puffs of air, like those made during aspirated speech, onto the skin of blindfolded volunteers. At the same time, they heard recordings of different syllables – either “pa”, “ba”, “ta” or “da” – all of which had been standardised so they lasted the same time, were equally loud, and had the same frequency.
Gick and Derrick found that the fake puffs of air could fool the volunteers into “hearing” a different syllable to the one that was actually played. They were more likely to mishear “ba” as “pa”, and to think that a “da” was a “ta”. They were also more likely to correctly identify “pa” and “ta” sounds when they were paired with the inaudible puffs.
Read the full post, complete with charts, graphs, and all! 
Uncategorized

Quantum physics for the win!

Beth Kelley

This has nothing to do with anthropology, it’s just awesome!

New quantum theories are messing with time!!! Holy cow (originally posted on Scientific American):
The main story ” Splitting Time from Space—New Quantum Theory Topples Einstein’s Spacetime,” describes recent excitement over a quantum theory of gravity proposed by physicist Petr HoYava of the University of California, Berkeley. Testing theories of quantum gravity in the laboratory is not possible, but computer simulations may offer the next best thing—and they seem to be lending support to HoYava gravity.
Jan Ambjørn of the Niels Bohr Institute at the University of Copenhagen and his colleagues have been using computer simulations to model quantum gravity based on spacetimes built from self-organizing “motes” that fall into place naturally.
So far, they have succeeded in creating a stable four-dimensional spacetime, when viewed at large distances. But when they zoomed in to small distances, they found a strange result—their universe seems to drop two dimensions. So where did the missing dimensions go?
HoYava believes that this dimension drop marks the point at which general relativity emerges in his theory of gravity. In his model, the shackles that force time and space to stretch in unison are removed at high energies and short distances. In a paper published in Physical Review Letters in April, he explains that within this regime, space stretches only a third as quickly as time. “The three spatial dimensions effectively mimic just one normal relativistic dimension,” he says, making it look as though two dimensions have vanished.
play

Imitation is the sincerest form of flattery – and bonding

Beth Kelley

Okay, first I just have to get it out of the way that Frans de Waal is a giant hippie. Big ol’ bio-anth hippie! The article I’m posting below undoubtedly reflects that. BUT, if you look past the hippiness, I think he’s onto something.

Okay, cue posting of Discover Magazine, general audience article about bonobos:

What intrigues me most about laughter is how it spreads. It’s almost impossible not to laugh when everybody else is. There have been laughing epidemics, in which no one could stop and some even died in a prolonged fit. There are laughing churches and laugh therapies based on the healing power of laughter. The must-have toy of 1996—Tickle Me Elmo—laughed hysterically after being squeezed three times in a row. All of this because we love to laugh and can’t resist joining laughing around us. This is why comedy shows on television have laugh tracks and why theater audiences are sometimes sprinkled with “laugh plants”: people paid to produce raucous laughing at any joke that comes along.

The infectiousness of laughter even works across species. Below my office window at the Yerkes Primate Center, I often hear my chimps laugh during rough-and-tumble games, and I cannot suppress a chuckle myself. It’s such a happy sound. Tickling and wrestling are the typical laugh triggers for apes, and probably the original ones for humans. The fact that tickling oneself is notoriously ineffective attests to its social significance. And when young apes put on their play face, their friends join in with the same expression as rapidly and easily as humans do with laughter.

Shared laughter is just one example of our primate sensitivity to others. Instead of being Robinson Crusoes sitting on separate islands, we’re all interconnected, both bodily and emotionally. This may be an odd thing to say in the West, with its tradition of individual freedom and liberty, but Homo sapiens is remarkably easily swayed in one emotional direction or another by its fellows.

Read the full article. I’ll wait.

Okay, are you back? Good.

I think he has a good point. There are lots of other data that really point out to me how important it is to have other individuals around, how much we learn from them, and how it’s hard for us to be the “lone wolf” (which doesn’t actually exist either, but that’s a different post all together).

The first type of play that humans participate in is imitating their moms and dads. Smiling at them, opening and closing their mouth the same way they do. Kids learn by mimicking and playing, trying the same stuff those around them do.

I don’t know if you need to go so far as to call it the new field of “embodied” cognition, but it is important to acknowledge that that part of us as social creatures definitely exists, and that basically, no man is an island. This is being re-shown every day.

Uncategorized

Large Prehistoric fauna and you

Beth Kelley

Featured in the New York Times:

Whenever modern humans reached a new continent in the expansion from their African homeland 50,000 years ago, whether Australia, Europe or the Americas, all the large fauna quickly disappeared. [Editorial comment: Hmmm, not exactly true, but I’ll go with it for now]

This circumstantial evidence from the fossil record suggests that people’s first accomplishment upon reaching new territory was to hunt all its all large animals to death. But apologists for the human species have invoked all manner of alternative agents, like climate change and asteroid impacts [I am not one of these, for the record, but I don’t think we were that well coordinated or that large a community to hunt out all the big fauna in North America].

A careful analysis of lake deposits in New York and Wisconsin has brought new data to bear on this heated debate. A team led by Jacquelyn Gill, a graduate student at the University of Wisconsin, has uncovered a critical sequence of events that rules out some explanations for the extinction of the large animals and severely constrains others.

The first event documented by Ms. Gill and her colleagues is the pace of extinction in North America, known from other research to have affected all animal species over about 2,200 pounds and half of those weighing more than about 70 pounds, the weight of a large dog.

Ms. Gill found a clever proxy for these disappearances. A fungus known as Sporormiella has to pass through the digestive system to complete its life cycle, and its spores are found in animal dung. By measuring the number of spores in the lake deposits, the Wisconsin team documented the steady disappearance of large animals from 14,800 years to 13,700 years ago, they reported in Thursday’s issue of Science.

The next clue to emerge from the lake deposits was the pollen of new plants including broad-leaved trees like oak. This novel plant community seems to have emerged because it was released from being grazed by large mammals.

The third clue is a layer of fine charcoal grains, presumably from fires that followed the buildup of wood.

This sequence of events has direct bearing on the megafauna whodunit. First, it rules out as the cause an impact by an asteroid or comet that occurred 12,900 years ago — the animals were dead long before.

It also excludes the standard version of a more popular explanation, that of habitat loss due to climate change. The extinction of large animals occurred before the emergence of the new plant communities. Ms. Gill said that some other aspect of climate, like direct temperature change, could have been involved [so it WAS climate change, then?].

The third suspect to be cleared is the people of the Clovis culture [editorial comment: well, duh!!!!], which first appeared some 13,000 years ago, well after the extinction event. The Clovis people have long been considered the first inhabitants of North America, which they probably reached by trekking across the land bridge that joined Siberia and Alaska during the last Ice Age.

So, do the new data exculpate humans of the murder of the North American mammoth? Not exactly. Butchered mammoth bones some 14,500 years old have been found in Wisconsin. There were evidently pre-Clovis people in North America, and they could have hunted the large animals to death. [no, no, look at frequency, not presence/non-presence of scraping on bones. Humans are also scavengers and opportunistic meat eaters]

But Ms. Gill is not yet willing to declare people guilty. “At this stage it’s too early to completely eliminate climate change,” she said.

Nor is it clear that the pre-Clovis people had the technology to take down large game like mammoths. [you can take down mammoth by driving them off a cliff, but I’ll go with this for now]. Ms. Gill plans to analyze many more lake bottoms before rendering any final verdict.

Am I just being grumpy here, or does this article sort of miss the point, or try to keep the “mystery alive” just for a good story? Interesting research, however.

language

Why chimps don’t talk?

Beth Kelley

All the news came out last week about the FOXP2 gene, but I can’t help and post it here a week late anyway:

Chimps, our nearest relative, don’t talk. We do. Now scientists have pinpointed a mutation in a gene that might help explain the difference.

The mutation seems to have helped humans develop speech and language. It’s probably not the only gene involved, but researchers found the gene looks and acts differently in chimps and humans, according to a study published online Wednesday by the journal Nature.

Lab tests showed that the human version regulated more than 100 other genes differently from the chimp version. This particular gene — called FOXP2 — mutated around the time humans developed the ability to talk.

“It’s really playing a major role in chimp-human differences,” said the study’s author, Daniel Geschwind, a professor of neurology, psychiatry and human genetics at the University of California, Los Angeles. “You mutate this gene in humans and you get a speech and language disorder.”

This tells you “what may be happening in the brain,” he said.

Read the full Associated Press story.

health

Mummies had clogged arteries

Beth Kelley2 Comments

A recent study of mummies found a significant number of the elite mummies (which most were) had clogged arteries, calcification of vessels, and other symptoms of heart disease and obesity.

This has been found before, but this is the largest study so far.

The BBC article I read suggested it was caused by the supposed large amounts of fatty meats being eaten by the elite.

However, as I suspected he might, Rafe said “There’s currently a bit of discussion on GNXP (Gene Expression). Michael Eades, auther of Protein Power, has published in the past showing that the Egyptian elite were in fact obese quite regularly, and attributes it to a diet that was very high in grains combined with a sedentary lifestyle, not the high in meat diet proposed in the BBC article.”

Quoted from Science Daily: “UC Irvine clinical professor of cardiology Dr. Gregory Thomas, a co-principal investigator on the study, said, ‘The findings suggest that we may have to look beyond modern risk factors to fully understand the disease.'”

Thoughts?