HOMINID EVOLN

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First Europeans Came From Asia, Not Africa, Tooth Study Suggests
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Kate Raviliousfor National Geographic News
August 6, 2007
Europe's first early human colonizers were from Asia, not Africa, a new analysis of more than 5,000 ancient teeth suggests.
Researchers had traditionally assumed that Europe was settled in waves starting around two million years ago, as our ancient ancestors—collectively known as hominids—came over from Africa.

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Fossil Tooth Belonged to Earliest Western European, Experts Say (July 2, 2007)
But the shapes of teeth from a number of hominid species suggest that arrivals from Asia played a greater role in colonizing Europe than hominids direct from Africa.
These Asian hominids may have originally come from Africa, the scientists note, but had evolved independently for some time.
(Related: "Did Early Humans First Arise in Asia, Not Africa?" [December 27, 2005].)
"Asia was also an important center for hominid speciation," said Maria Martinón-Torres, a scientist at the National Research Center on Human Evolution in Burgos, Spain, who led the study.
The finding suggests that the hominid family tree could be much more complex than previously thought (explore an interactive atlas of human migration).
Genetic Safe
Species from the genus Australopithecus and the genus Homo arrived in Europe between two million and 300,000 years ago.
Until recently, a lack of fossils from this time period had made it difficult to piece together hominid evolution and migration patterns.
But using the latest fossil findings, Martinón-Torres and colleagues were able to examine more than 5,000 teeth from two-million-year-old Australopithecus and Homo skeletons from Africa, Asia, and Europe.
The shape of the teeth offered clues about each species' genetic lineages.
Teeth are like the safe-box of the genetic code," Martinón-Torres said.
That's because—compared to bones—teeth change shape very little once they are formed, and their shape is strongly influenced by genetics.

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RELATED
China's Earliest Modern Human Found (April 3, 2007)
Human Genetics Overview
Fossil Tooth Belonged to Earliest Western European, Experts Say (July 2, 2007)
The researchers classified each of the teeth using more than 50 indicators, such as fissure patterns, overall size, and length-to-width ratio.
"We looked at the entire landscape of the teeth—the mountains, valleys, ridges—everything," Martinón-Torres said.
What they found is that European teeth were more similar to Asian teeth than they were to African teeth.
However, the results don't rule out African influence on European genes.
"This finding does not necessarily imply that there was not genetic flow between continents," Martinón-Torres and colleagues write in their paper, "but emphasizes that this interchange could have been both ways."
The work will be published in tomorrow's issue of the Proceedings of the National Academy of Sciences.
Fluid Migrations
Rather than a one-way stream of people coming from Africa, Martinón-Torres and colleagues think there must have been a more fluid pattern of migrations.
"Just because people had come out of Africa didn't mean that they couldn't turn around and go back again," she said.
The researcher also believes that climate, food, and geography were major influences on hominid migration patterns.
The Sahara, for example, presented a big barrier for movement out of Africa and directly into Europe (see photos and read a related feature about athletes who ran across the Sahara earlier this year).
Rather than struggling across the Sahara, it appears that human ancestors spread in many directions before arriving in Europe.
Erika Hagelberg, a geneticist from the University of Oslo in Norway, is impressed with the study, but cautious about how it should be interpreted.
"The study shows that the genetic impact of Asia on Europe is stronger than that of Africa. But the teeth can't tell us the direction or the time when people migrated," she said.
Nonetheless, the new study does complement direct gene studies and supports the idea that hominids evolved independently in many different parts of the world.
"The fossil teeth are a way to study the traits of past peoples," Hagelberg said, "and help balance the work being done on the genes of people alive today."



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/////////////////////////Physicists Get Two Atoms to Communicate: First Step Toward the Quantum Internet
02 November 2007, 20:02:38 admin
The University of Michigan researchers said their accomplishment marks an advance toward super-fast quantum computing and data transmission. The scientists used light to establish what's called "entanglement" between two atoms, which were trapped one meter apart in separate enclosures. They described entangling as similar to controlling the outcome of one coin flip with the outcome of [...]



//////////////////Primate Mind
Let's take a few steps back from our discussion of human brains and consider the minds and brains of simpler animals. This will set the stage for describing the transition from monkeys through apes to the hominids of about 2 million years ago (we will save more recent times for later chapters). We can then consider the minds of contemporary monkeys and apes in the search for types of intelligence that might have antedated ours. We share with chimpanzees and some other great apes mental attributes that appear to be unique in the animal kingdom, reflecting the appearance of new brain structures and processes.
The Question of Animal Consciousness
Consciousness is a device for focusing awareness through the linking of emotions and feelings to sensing and acting. It is an emergent level of organization that can coordinate and direct the neuronal assemblies from which it is derived. If we take consciousness to be an increasingly refined evolutionary adaptation, it seems reasonable to grant other animals a kind of consciousness that correlates with the complexity of their brains---to consider it a matter of degree rather than an all-or-nothing phenomenon.



//////////////////////Undoubtedly humans are the outgrowth of a whole series of selective pressures which forced our predecessors to learn to eat new foods, live in new habitats, develop new reproductive strategies such as kinship. Each Ice Age has probably left behind a residue of skills which, like the boulders scattered across the landscape, remain after the vicissitudes have vanished. The generalized animal developed out of leftover specializations, just as the general-purpose computer developed out of such leftover special-purpose computers as the player piano and control systems for antiaircraft guns. So, did generalized human language evolve from specialized hunting "computational" skills? Bootstrapping language through better throwing? If oral-facial sequencing built upon the throwing-sequencing machinery of the left brain, then it would be natural for the expanding repertoire of verbal expressions to also settle alongside in the left brain--and so to set the stage for more sophisticated language, hence culture, and science, and all the rest. Is language, that sine qua non of humankind, merely a side effect of braining rabbits? Well, is that worse than its being an offshoot of the vocalizations used for threats and warning cries? Those species-specific vocalizations in monkeys might, of course, also have served as the scaffolding upon which language was built. Certainly they are a more obvious choice than throwing. But that seemingly logical proposition has one problem: the cortical specializations for those vocalizations in monkeys are not located anywhere near the Sylvian fissure, around which the human language area has come to reside. They are far away, near the midline of the brain, just in front of the motor area for the foot and just above the corpus callosum. So perhaps language was built on the scaffolding of sequencing rather than snarls. From gestures to grammar.... Suppose that's why chimps are better at sign language than spoken language? Or why modern human males, who are often more natural pitchers, have language more strongly lateralized than modern females (though this is hardly to be envied: males are far more likely than females to suffer aphasia after a left-hemisphere stroke).



////////////////////////Plant Sterols
Plant sterols are extracts of certain plants that, when ingested, inhibit the absorption of cholesterol in the small intestine. Thus, dietary cholesterol never gets into the system. Two plant sterols are now available in a spreadable form, as a substitute for margarine.
An extract of the soy plant – sitosterol – is available in a product called Take Control (Lipton). And an extract of pine needles – sitostanol – is available in a similar product called Benechol (McNeil). Neither product tastes exactly like margarine and are unsuitable for cooking, but most people find them to be reasonably good to eat. Spreading 1 – 2 tablespoons of the spread on bread each day, as a substitute for margarine (and, of course, in combination with a low fat diet,) can reduce LDL cholesterol levels by up to 10%.



///////////////////////Soy products
Soy products have been touted as having so many outlandishly beneficial effects that one feels like a huckster even mentioning them. But the fact is, several well-conducted studies have shown that soy products can reduce cholesterol levels significantly.
“Soy products” refers to the soy isoflavones – estrogen-like substances found in various plants – and soy protein. To produce a reduction in cholesterol levels, both the isoflavones and soy protein apparently must be ingested.
A diet containing 25 grams of soy protein and 50 to 60 milligrams of soy isoflavones per day can reduce LDL cholesterol levels by about 10%.




/////////////////////Fiber for cholesterol lowering
Several studies have now documented that dietary fibers can cause a significant reduction in cholesterol levels. While any fibers tend to be beneficial, the best form of fiber for cholesterol reduction appears to be foods containing soluble fibers – that is, fibers that dissolve in water.
The soluble fibers contained in oats, for instance, have been shown to have a substantial impact on cholesterol levels when added to a low-fat diet. Other foods high in soluble fibers are lentils, pinto beans, citrus, black beans and barley.
For those people (and you know who you are) that prefer taking medical products instead of eating healthy food, psyllium (the fiber found in Metamucil,) has also been demonstrated to cause a significant reduction in cholesterol levels (but tragically, only in conjunction with a low-fat diet).



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