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Wednesday, December 30, 2009

More mysterious hominids

Featured in Discover Magazine: The Boskops.
Skulls found of this group had a cranial capacity of 1,980 cc and a child-like face. The combination of a large cranium and immature face would look decidedly unusual to modern eyes, but not entirely unfamiliar. Such faces peer out from the covers of countless science fiction books and are often attached to “alien abductors” in movies.


The combination of a large cranium and immature face would look decidedly unusual to modern eyes, but not entirely unfamiliar. Such faces peer out from the covers of countless science fiction books and are often attached to “alien abductors” in movies. The naturalist Loren Eiseley made exactly this point in a lyrical and chilling passage from his popular book, The Immense Journey, describing a Boskop fossil:
“There’s just one thing we haven’t quite dared to mention. It’s this, and you won’t believe it. It’s all happened already. Back there in the past, ten thousand years ago. The man of the future, with the big brain, the small teeth. He lived in Africa. His brain was bigger than your brain. His face was straight and small, almost a child’s face.”

Boskops, then, were much talked and written about, by many of the most prominent figures in the fields of paleontology and anthropology.

Yet today, although Neanderthals and Homo erectus are widely known, Boskops are almost entirely forgotten. Some of our ancestors are clearly inferior to us, with smaller brains and apelike countenances. They’re easy to make fun of and easy to accept as our precursors. In contrast, the very fact of an ancient ancestor like Boskop, who appears un-apelike and in fact in most ways seems to have had characteristics superior to ours, was destined never to be popular.

Read the whole article
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Tuesday, December 29, 2009

Wide spread tool use in primates

Despite the common perception, tool use is not just a sporadic behavior among animals; it's especially prevalent in primates.


For example, chimps use cleavers and anvils as tools to chop food. Chimps in the Nimba Mountains of Guinea, Africa, use both stone and wooden cleavers, as well as stone anvils, to process Treculia fruits.
The apes are not simply cracking into the Treculia to get to otherwise unobtainable food, say researchers.
Instead, they are actively chopping up the food into more manageable portions.
PhD student Kathelijne Koops and Professor William McGrew of the Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, UK, studied a group of chimps living wild in the Nimba Mountains.
The apes' use of such tools can be surprisingly sophisticated. "For example, nut-cracking in the Bossou chimpanzee community in Guinea involves the use of a movable hammer and anvil, and sometimes the additional use of stabilising wedges to make the anvil more level and so more efficient," explains Ms Koops. "Termite fishing in some chimpanzee communities in the Republic of Congo involves the use of a tool set, i.e. different tool components used sequentially to achieve the same goal.
"These chimpanzees were found to deliberately modify termite fishing probes by creating a brush-end, before using them to fish for termites."


How do these animals keep their teeth healthy? Floss after a meal. At least one does. A macaque in Japan flosses its teeth with its hair, demonstrating that humans aren't the only animals that clean their teeth and invent tools to help with the task.
The flosser, a free-ranging, middle-aged, female Japanese macaque named Chonpe, may have come up with the tool and the idea, according to a new study that will appear in the January issue of Primates.
Lead author Jean-Baptiste Leca told Discovery News that dental flossing could have been a fortuitous yet "accidental byproduct of grooming."
Leca, a post-doctoral fellow at Kyoto University's Primate Research Institute, explained that "Japanese macaques sometimes bite into hair or pull it through their mouths to remove external parasites."
The hair might have become stuck in Chonpe's teeth, and as she drew the hairs out, "she may have noticed the presence of food remains attached to them."
"The immediate reward of licking the food remains off the hair may have encouraged her to repeat the behavior for the same effect in the future," he added.

Read more about meat hammering and flossing.


Wednesday, December 23, 2009

Developing minds

Lots of cool news came out recently about human development, from chimps to little humans:

Wild chimps have been shown to understand fire and how it moves, and don't freak out like other animals do. This is exciting because humans so far had been the only animals documented as keeping their cool around fire...for the most part.

Since we're in the jungle, it's once again been show that it's good for kids to go roll around in the dirt; for one thing it correlates with lower heart disease when they're older.

But back to brain wiring, kids who get intensive language training when they're young, like reading, actually have their brains re-wired, in a good way.

New education research is also showing that kids may understand Math at a much earlier age than previously though, and there are ways that they can learn the concepts just as early as we try to teach them language.

One of the skills kids can develop is compartmentalization, which it turns out cavemen could also do much earlier than previously thought; for example, they made different, compartmentalized work stations in their camps, rather than spread everything around and sleep right next to the meat-processing spot.

Speaking of stone-age types, a study has come out that counters the idea that hunter-gatherers didn't eat any grains at all.

All this data almost makes me want to grab some popcorn and pop it over a fire while playing math games. But not before I go work in my garden patch.

Tuesday, December 22, 2009

Even bacteria get lonely

Don't worry if you're feeling sort of lonely during this time of year; even bacteria feel alone sometimes, and there's trillions of them.

But, if you're really feeling blue, you can always move to Florida; states that get the most sun also tend to have the happiest residents.

Thursday, December 17, 2009

Mayan king may have been a foreigner

From Science News:

A man’s skeleton found atop a stone slab at Copán, which was the capital of an ancient Maya state, contains clues to a colonial expansion that occurred more than 1,000 years before Spanish explorers reached the Americas.
The bones come from K’inich Yax K’uk’ Mo’, or KYKM for short, the researchers report in an upcoming Journal of Anthropological Archaeology. KYKM was the first of 16 kings who ruled Copán and surrounding highlands of what is today northern Honduras for about 400 years, from 426 to 820, say archaeologist T. Douglas Price of the University of Wisconsin–Madison and his colleagues. KYKM’s bone chemistry indicates that he grew up in the central Maya lowlands, which are several hundred kilometers northwest of Copán.
Along with inscriptions at Copán, the new evidence suggests that the site’s first king was born into a ruling family at Caracol, a powerful lowland kingdom in Belize. KYKM probably spent his young adult years as a member of the royal court at Tikal, a Maya kingdom in the central lowlands of Guatemala, before being sent to Copán to found a new dynasty at the settlement there, Price’s team proposes.
“These findings reinforce the notion that the Copán state was founded as part of a colonial expansion,” says archaeologist and study coauthor Robert Sharer of the University of Pennsylvania in Philadelphia. “They also demonstrate the widespread connections maintained by Maya kings.” This line of investigation aims to unravel how Classic era Maya city-states, which dominated parts of Mexico and Central America from about 200 to 900, originated and developed.
Hieroglyphics at Copán that were deciphered more than 20 years ago refer to KYKM as a foreigner who was inaugurated as king in 426 and arrived the next year. But it has been unclear whether the inscriptions referred to an actual historical event or were a form of royal propaganda. In 2007, archaeologist David Stuart of the University of Texas at Austin noticed that an inscription carved on a Copán stone monument referred to KYKM by a title indicating that he was originally a Caracol lord.
Archaeologists Arlen Chase and Diane Chase of the University of Central Florida in Orlando, who direct excavations at Caracol, consider it plausible that Copán’s first king was a Caracol lord but doubt that he arrived via Tikal. No signs of a political relationship between Caracol and Tikal appear at the time that KYKM took over at Copán, Arlen Chase notes.
Instead, KYKM probably came directly from Caracol, Arlen Chase says. By the year 150, Caracol hosted numerous royal activities and had extensive ties to settlements near Copán. “It would not be surprising for Copán to have coveted a Caracol individual to become their first ruler,” he says.

Photo Credit: Courtesy of the Early Copán Acropolis Program, U. of Penn. Museum and Instituto Hondureno de Antropologia e Historia

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The evolutionary fitness of dancing?

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?

Read full post

Wednesday, December 16, 2009

Beauty is only city-deep

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.


Monday, December 14, 2009

ADHD brains: taking the long way home

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

Tool use in the octopus

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."


Read more

Thursday, December 3, 2009

Listen with your skin

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!