Re: Human evolution, radically reappraised (March 26): I don’t know if it’s the fault of the people conducting the study themselves, or your editors, but your article reeked of scientific ignorance, dishonesty, and outright idiocy. Your article made rings and rounds among far right and racist/racialist blogs and websites- do you think this is good? At all? I’ll just point them out.
“The proposal is “truly fascinating,” wrote University of Chicago geneticist Bruce Lahn in an email. He wasn’t involved in the work, though he did conduct earlier research finding that evolution may still be ongoing in the brain.”
Lahn’s “research” has actually been shown to be outright wrong:
http://www.gnxp.com/blog/2006/08/brain-size-genes.php
Aside from the fact that it exhibited substantial lack of knowledge- although this being little known, and I’ll detail it later- about the dynamics of the human brain, it didn’t make any sense to begin with. How could such minute alleles be involved with things like agriculture and art? What diffrentiated this from early exhibitions of abstract though? It even showed large disparities among ethnic groups where it was found in high frequencies, and some of the genes were completely absent in Vietnamese and Cambodians, yet having their highest frequencies in native americans and papuans.
This is where the outright bullsh*t comes in.“Hawks and Cochran analyzed measurements of skulls from Europe, Jordan, Nubia, South Africa, and China in the past 10, 000 years, a period known as the Holocene era. They also studied European and West Asian skulls from the end of the Pleistocene era, which lasted from two million years ago until the Holocene. “A constellation of features” changed across the board, Hawks and Cochran wrote in their presentation. “Holocene changes were similar in pattern and. . . faster than those at the archaic-modern transition,” the time when so-called modern humans appeared. But these changes “themselves were rapid compared to earlier hominid evolution.” Hominids are a family of primates that includes humans and their extinct, more ape-like though upright-walking ancestors and relatives.”
The person who wrote this article didn’t even clarify what “features” Hawks and Cochran were reffering to- but if it’s that of skull features, so what? When one looks into the heritability of various physical and biochemical variables of the human body, you’ll realize something- there’s really few fixed physical differences that exist among human ethnic groups. How is a rapid change in cranial features an example of accelerating human evolution? All this is saying is that the genetic structures that control for these features changed quickly- which isn’t uncommon, at all, in humans.
It’s been observed among native americans, it’s been observed among australian aborigines- they’re southeast asians, the single most divergent human ethnic group on Earth, yet they carry many physical features common to archaic humans and extinct hominids. Is this just one of the many examples of Hawks and Cochran’s ignorance?
Hawks and Cochran also analyzed past genetic studies to estimate the rate of production of genes that undergo positive selection-that is, genes that spread because they are beneficial. “The rate of generation of positively selected genes has increased as much as a hundredfold during the past 40,000 years,” they wrote.
Um. So this is their big proof? This has been known for a very long time, and it says nothing of the big question which all of this vexes on- the idea that some human ethnic groups could have fixed, differing brain structure. Racial differences. This is just saying that the frequency of phenotypes and selective genes has increased in frequencies, but what does this even prove? It’s a fact, a blatant one, that major structural differences in the brains of primates- hominids especially- take the onset of 1 million years or more. Atleast from what we can interpret from the archaeological data. Then you have to take into account the exertion of phenotypic pressures upon particular traits, and well. . . . Our species has been transisting constantly for such a short period of time. The time we’ve been migrating out of africa is minute.
A “thing that should probably worry people is that brains have been getting smaller for 20,000 to 30,000 years,” said Cochran. But brain size and intelligence aren’t tightly linked, he added. Also, growth in more advanced brain areas might have made up for the shrinkage, Cochran said; he speculated that an almost breakneck evolution of higher foreheads in some peoples may reflect this. A study in the Jan. 14 British Dental Journal found such a trend visible in England in just the past millennium, he noted, a mere eyeblink in evolutionary time.
And here’s the biggest idiocy, and while I guess Hawks and Cochran can be exscused, here it is:
http://www.cpa.ca/cpasite/userfiles/documents/publications/cjep/petertxt.htm
Fun fact: Brain size varies substantially within ethnic groups, it correlates only by. 20 with IQ (in men), and gains in IQ would invariably result in gains in brain growth- this being well established by the effects of omega-3 and breastfeeding on brain development, along with that of malnutrition and proper nutrition, and the fact that the heritability of IQ rises with age- basically saying that environmental effects on IQ become lessened as someone’s brain matures.
So Hawks and Cochran commit insane levels of scientific ignorance with this. If the distribution of mental faculties involved with intelligence somehow changed so radically in the span of a few thousand years- which is outright impossible- wouldn’t this be blatantly apparent in some sort of correlationary study? BTW, I’ve known of these prehistoric populations- they’ve been observed all over the globe. They were found in early archaic humans, along with Homo Sapiens Idaltu, both having cranial capacities in the mid 1, 500’s. In fact, such populations have been observed at high frequencies among Papuan tribal peoples (just look at photos- some of them have strikingly large heads) and a few isolated regions of Australia. Nobody knows for sure what causes this. This stupidity also reminds me of a study that came out amidst the controversy over Lahn’s work- some people hypothesized that the APSM genes came from interbreeding with neanderthals. I’ll say it- that idea is completely retarded. Humans exceeding neanderthal brain size are very common, and neanderthals are definately a distinct species- and don’t they see anything unethical about basically saying that europeans, north africans, middle easterners, and indians aren’t fully human?Cochran... speculated that an almost breakneck evolution of higher foreheads in some peoples may reflect this. A study in the Jan. 14 British Dental Journal found such a trend visible in England in just the past millennium, he noted, a mere eyeblink in evolutionary time. . . . .
Oh god. How can this have even been published via peer review? High foreheads aren’t anywhere near of an indicator of evolutionary status. This feature varies profoundly within ethnic groups, and orangutans have surprisingly high foreheads despite being a “lower” species of ape. The brain basically molds to fit into the way the skull grows, so no, people with lower foreheads aren’t less intelligent.
Whatever the implications of the recent findings, McKee added, they highlight a ubiquitous point about evolution: “every species is a transitional species.”
Yes- these changes they found say nothing about rapid human evolution. And again, what does rapid physical changes prove? I’m very, very sorry if I came off as rude- but I’m just appalled at how poor this study and article were, and how it was so quickly abused by far right groups. Is there anyway to even contact Cochran and Hawks?