May 30, 2012
Hey America, Is Your Head Big Or Is It Just Me?
Michael Harper for RedOrbit.com
Americans are known to be a large, boisterous, get-your-own kind of people. Look at our heritage: Our ancestors didn´t like to be pushed around and told how to live, so they just left to start their own country. We wanted to spread across the nation, so we headed off to the West on our own. We´re a proud nation built on a do-it-yourself mentality. As such, is it so hard to believe that we have a big head when it comes to our achievements?Actually, it shouldn´t be that hard to believe. In fact, it´s even been confirmed. In a new study conducted at the University of Tennessee, Knoxville, Americans´ heads really are getting bigger.
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 as far back as the mid-1800s all the way through the mid-1980s. As they conducted their research, they noticed American skulls became larger, taller and narrower as time progressed. As a result, the faces on the skulls also became significantly narrower and higher.
So by how much did these skulls grow? The UT researchers found the average height from the base of the skull to the top has increased by 0.3 inches in men, and the overall skull size has increased by 200 cubic centimeters, or the size of a regular tennis ball. Women´s skulls have grown .27 inches taller, about 180 cubic centimeters overall.
All told, the average skull studied by the UT team has increased 6.8% in height since the late 1800s. Body height has also increased by 5.6%, though our average femur length has only grown by 2%. Interestingly, our heads have continued to get larger even as our overall heightening has slowed or completely stopped.
The UT anthropologists have said they cannot say exactly what has caused this trend, only that they have observed it. True to the American spirit, however, the team has come up with their own explanations for why this trend has occurred.
“The varieties of changes that have swept American life make determining an exact cause an endlessly complicated proposition,” said Lee Jantz, according to a press release announcing the study´s results.
“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.”
One such guess as to our ever-growing craniums is the age at which we mature. The researchers have noted that Americans have been maturing earlier and earlier with each passing generation.
The researchers also say our giant heads could be a result of the obesity epidemic which has been affecting America for the past many years.
“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.”
Of all the skulls studied by the team, they noticed a greater growth trend in American skulls as opposed to European skulls.
Those advantageous and entrepreneurial readers may want to take this new study as a cue to corner the market on oversized hats for all ages. Other money-making opportunities could include: Larger headbands, oversized sunglasses, wider doorways and more flexible over-the-ear headphones.
The researchers presented their findings on April 14 at the annual meeting of the American Association of Physical Anthropologists.