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Gene that increases brain cells found in humans but not chimps

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From LiveScience,

‘Big Brain’ Gene Found in Humans, Not Chimps

A single gene may have paved the way for the rise of human intelligence by dramatically increasing the number of brain cells found in a key brain region.

This gene seems to be uniquely human: It is found in modern-day humans, Neanderthals and another branch of extinct humans called Denisovans, but not in chimpanzees.

If it is that simple, one could try inserting such material into various life forms, and see if they get any smarter:

Then the team inserted and expressed (turned on) this DNA snippet in the brains of mice. Though mice normally have a tiny, smooth neocortex, the mice with the gene insertion grew what looked like larger neocortices; these amped-up brain regions contained loads of neurons and some even began forming the characteristic folds, or convolutions, found in the human brain, a geometry that packs a lot of dense brain tissue into a small amount of space. (The researchers did not check to see if the mice actually got smarter, though that is a potential avenue of future research, Florio said).

Hmmm. Get back to us. The ability of the cells to stay alive in that environment is one thing; their ability to produce heritable increases in intelligence over generations, absent the right environment, would be another.

Also:

The evolution from primitive apes to humans with complex language and culture has taken millions of years. Some 3.8 million ago, Australopithecus afarensis, the species typified by the iconic early human ancestor fossil Lucy, had a brain that was less than 30 cubic inches (500 cubic centimeters) in volume, or about a third the size of the modern human brain. By about 1.8 million years ago, Homo erectus was equipped with a brain that was roughly twice as big as that of Australopithecus. H. erectus also showed evidence of tool and fire use and more complex social groups.

Hey, wait a minute. We happened to find this out about Homo erectus, but we haven’t found it out about Australopithecus. They didn’t think that about H. erectus either until quite recently.

Human paleontologists used to say Neanderthals couldn’t do artwork, until some researchers found evidence of Neanderthal artwork. See, for example, Neanderthal Man: The long-lost relative turns up again, this time with documents, and A deep and abiding need for Neanderthals to be stupid. Why?

Discoveries can’t be taken back, but newer ones can still be made. The need to find a human groupthat is “incapable” of some intellectual feat relates mainly to the Darwinian need for separate “species” of humans. For that, see The Little Lady of Flores spoke from the grave. But said what, exactly?

(Science) target=”another”>Abstract: Evolutionary expansion of the human neocortex reflects increased amplification of basal progenitors in the subventricular zone, producing more neurons during fetal corticogenesis. Here, we analyze the transcriptomes of distinct progenitor subpopulations isolated by a cell polarity-based approach from developing mouse and human neocortex. We identify 56 genes preferentially expressed in human apical and basal radial glia that lack mouse orthologs. Among these, ARHGAP11B has the highest degree of radial glia-specific expression. ARHGAP11B arose from partial duplication of the Rho GTPase-activating-protein–encoding ARHGAP11A on the human lineage after separation from the chimpanzee lineage. Expression of ARHGAP11B in embryonic mouse neocortex promotes basal progenitor generation and self-renewal, and can increase cortical plate area and induce gyrification. Hence, ARHGAP11B may have contributed to evolutionary expansion of human neocortex. (paywall) Science News item.

See also: Neuroscience tried wholly embracing naturalism, but then the brain got away

The former correct view, one guesses:

Comments
Well, if what they mean is they found a "gene" and the definition of a gene is a "concept", then it all makes perfect sense.phoodoo
March 2, 2015
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It emerged..... Darwin speak for magic......Andre
March 1, 2015
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