Anthropologists find American heads are getting larger

May 30, 2012

White Americans' heads are getting bigger. That's according to research by forensic anthropologists at the University of Tennessee, Knoxville.

Lee Jantz, coordinator of UT's Forensic Anthropology Center (FAC); Richard Jantz, professor emeritus and former director of the FAC; and Joanne Devlin, adjunct assistant professor, examined 1,500 skulls dating back to the mid-1800s through the mid-1980s. They noticed U.S. skulls have become larger, taller and narrower as seen from the front and faces have become significantly narrower and higher.

The researchers cannot pinpoint a reason as to why American shapes are changing and whether it is primarily due to evolution or lifestyle changes.

"The varieties of changes that have swept American life make determining an exact cause an endlessly complicated proposition," said Lee Jantz. "It likely results from modified growth patterns because of better nutrition, lower infant and maternal mortality, less physical work, and a breakdown of former ethnic barriers to marriage. Which of these is paramount we do not know."

The researchers found that the average height from the base to the top of the skull in men has increased by eight millimeters (0.3 inches). The skull size has grown by 200 cubic centimeters, a space equivalent to a tennis ball. In women, the corresponding increases are seven millimeters and 180 cubic centimeters.

Skull height has increased 6.8 percent since the late 1800s, while body height has increased 5.6 percent and femur length has only increased about 2 percent. Also, skull-height has continued to change whereas the overall heightening has recently slowed or stopped.

The scientists also noted changes that illustrate our population is maturing sooner. This is reflected in the earlier closing of a separation in the bone structure of the skull called the spheno-occipital synchondrosis, which in the past was thought to fuse at about age twenty. Richard Jantz and Natalie Shirley, an adjunct assistant professor in the FAC, have found the bone is fusing much earlier — 14 for girls and 16 for boys.

America's obesity epidemic is the latest development that could affect skeletal shape but its precise effects are unclear.

"This might affect skull shape by changing the hormonal environment, which in turn could affect timing of growth and maturation," said Richard Jantz. "We know it has an effect on the long bones by increasing muscle attachment areas, increasing arthritis at certain joints, especially the knee, and increasing the weight bearing capacity."

The research only assessed Americans of European ancestry because they provided the largest sample sizes to work with. Richard Jantz said changes in skeletal structure are taking place in many parts of the world, but tend to be less studied. He said research has uncovered shifts in shape in Europe though it is not as dramatic as seen in the U.S.

The findings were presented on April 14 in Portland, Ore. at the annual meeting of the American Association of Physical .

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2.3 / 5 (12) May 30, 2012
I can see the movie trailers now - "DESERT DWELLING FAT MONGLOYDZ WITH GUNS", An Asian documentary about life in the US in the year 3000.
2.7 / 5 (12) May 30, 2012
"Americans' heads are getting bigger"...I didn't think it was even possible!
2.3 / 5 (22) May 30, 2012
Bigger heads does not equal more intelligence.
4.2 / 5 (5) May 30, 2012
It must be the hot air inside expanding :oD
4.2 / 5 (5) May 30, 2012
A bizarre enigma...heads getting bigger while IQ's getting lower...grey-matter being replaced by brown-matter perhaps.
1.9 / 5 (9) May 30, 2012
Their butts are getting much bigger as well.
2.5 / 5 (8) May 30, 2012
We shouldn't be so hard on our American "Friends". After all they are living in a dying nation.

No doubt, chronic depression is behind much of the decline in their IQ scores relative to other nations.
1 / 5 (1) May 30, 2012
"They noticed U.S. skulls have become larger, taller and narrower as seen from the front and faces have become significantly narrower and higher." A description that matches the appearance of the characters of The Simpsons Family.

http://www.linkme...bies.jpg simpsons&um=1&hl=en&sa=N&biw=1107&bih=756&tbm=isch&tbnid=kX--y_shVxKChM:&imgrefurl=,r:8,s:68,i:309&tx=119&ty=94
2.2 / 5 (10) May 30, 2012
Maybe it's due to the increased number of c-section births.
3 / 5 (3) May 30, 2012
Maybe it's due to the increased number of c-section births.

But heads are getting more narrow and tall, not more wider, so it should pass birth canal more easily? Meaning should be less need of Caesarean.
3.7 / 5 (3) May 31, 2012
Oh no... America is turning into a bunch of dick heads. (joking)
2.1 / 5 (7) May 31, 2012
We shouldn't be so hard on our American "Friends". After all they are living in a dying nation.

No doubt, chronic depression is behind much of the decline in their IQ scores relative to other nations.

No doubt Freud could find some subconscious information about
Vendicar Decarian here.
3.7 / 5 (3) May 31, 2012
Freud is dead, along with all of his theories.
1 / 5 (7) May 31, 2012
The ancient skulls were longer and narrower, then they started becoming more rounded, now they are switching back again. One of the big question in the pre-Columbian Americas is why the skulls of the paleo Indians were longer and narrower than the people of more recent times. Some of the "experts" say this is because of two migrations with the round heads exterminating the long heads about 6000 years ago even though the DNA in the two groups shows no change.
Other say environment, diet, and world wide change in most human skulls are the reasons.
1.8 / 5 (10) May 31, 2012
Bigger heads does not equal more intelligence.

Who thought it did? Seriously, what is wrong with you?
2.1 / 5 (7) May 31, 2012
Bigger heads does not equal more intelligence.

Who thought it did? Seriously, what is wrong with you?
"Then how do you explain a womans brain is smaller than a mans?" -Borat
1.7 / 5 (12) Jun 01, 2012
As American heads are expanding so is the universe.
1.5 / 5 (8) Jun 02, 2012
american heads are changing shape, and nobody knows why? meanwhile we have drugs in corporate food and corporate water supply, but those drugs are perfectly safe, right, riiight?? yeah exactly wrong. if people ate natural food like their ancestors did, weird zombie effects like these would not happen, but unfortunately this is the corner-cutting generation that prefers aspartame over sugar, pink slime over actual meat, GMO's over natural food, etc. no surprises here at all. you reap what you sow. after gradual change forced over the course of decades or centuries, humans eventually will be less than 50% biological and more than 50% engineered themselves, hence life will be even less valuable than it's becoming now, we'll be able to slaughter ourselves by the millions without any guilt, and it all starts with things like the inexplicably changing head shapes that everyone just shrugs at, yay
Marc Holmes
2 / 5 (4) Jun 02, 2012
My hypothesis is that it is cause by the use of growth hormone in American food in cattle and sheep (which has been increasing in their food supply since the 1980s). The growth hormone has been linked by Cornell University to early puberty in girls (which lines up with the early fusing in girls). Cross referencing the head sizes by diets (vegans, etc) should be able to confirm.
1 / 5 (7) Jun 02, 2012
Bigger heads does not equal more intelligence.

And yet average I.Q. increases by 3 points per decade, for reasons currently "unknown" and has been doing so for apparently about as long as I.Q. tests have existed, or as long as it's been tracked anyway.

(Look it up, OTTO. If you don't believe it, piss off.)

The scale is re-adjusted from time to time so that "normal" always equals 100.

And for example, the harder questions on a test are much harder than they used to be many decades ago to adjust for this.

It is unclear what portion of this is from some sort of increase in intelligence, and what portion is from increase in average education level.

I'm not a racists, but it's also clear that white people and asians score significantly higher than blacks and hispanics on most I.Q. tests and in cranial capacity, at least on average.
1 / 5 (8) Jun 02, 2012
And so anyway, by that reasoning, if the plus 3 points per decade trend continues, the "average" child born in 100 years will have an I.Q. equivalent to what we would presently rate as 130, as an adult, when adjusted for the same age group.

And by that standard I am 73 years ahead of my time in both verbal I.Q. and Raven's Squares I.Q...

Anyway, more seriously, the increasing head size may in fact have a positive correlation to the I.Q. score increase.

It's possible since there are more and more c-sections that children with higher brain capacity are delivered successfully more often, and therefore those genes which allow for larger brains are passed on to future generations, when they otherwise would not be passed on if the child died while the woman was in labor.

So after a few generations, these "big brain" genes could be reinforced, particularly in individuals how have big brains for 2 or more unrelated genetic reasons.
1 / 5 (8) Jun 02, 2012

The U.S. is rated 98 on average, with 115 for college graduates, and 85 for African Americans.

If you consider the number of immigrants from Cuba, Mexico, and other W. HEMISPHERE hispanic nations are almost as bad as the blacks, at 85 and 87, then you can see that illegal immigration hurts the U.S. national average I.Q. about as bad as the black population. Although that could be misleading, because it could be that the "smart" ones are smart enough to come here, and the dumb ones aren't smart enough to try...

When you get near the bottom of the list, the entire countries is close to what we used to call "retarded" in the U.S. a few decades ago....and that's the ones who were educated enough to test...yeah...

It's possible that maybe 1/4th to as much as a half of the points ultimately come out of "education" even if it isn't realized, and the first half of points are actually "innate intelligence".
5 / 5 (1) Jun 03, 2012
Mine only seems to have gotten pointier, maybe I'm doing it wrong.
5 / 5 (1) Jun 03, 2012
IQ is an (unsatisfying) attempt to put a number to something not easily quantifiable. Also, when you use the term, people will interpret it differently. And English being mungeable, there's no way to prevent that.
Curious about the national/cultural differences in IQ, I browsed the site. Some points were made:
- nurturing doesn't affect (which implies it's all nature)
- lots of comments regarding high scoring people aggregating, but little conjecture regarding why there are low-IQ groups
- except for one guess that stress brought by environmental challenges (i.e. cold winters) made passing on high-IQ characteristics advantageous.
If this latter were true, it would seem our industrialized society IQs should be decreasing, not increasing. We are no longer challenged to think hard. Pigeonholed at work. Spending the rest of our time watching lowest common denominator entertainment on TV.
5 / 5 (1) Jun 03, 2012
Creationism and warming climate denial is getting their heads to explode...
(just those who match these descriptions)
1.4 / 5 (5) Jun 03, 2012
Which of these is paramount we do not know

Maybe all of them are?

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