US Heads Have Gotten Taller And Narrower Since 19th Century
White Americans have heads that are shaped differently than their ancestors from the 19th century according to a recently released study.
Examining skulls from the mid-1800s through the mid 1980s forensic anthropologists at the University of Tennessee, Knoxville took measurements from 1,500 skulls in an attempt to determine how head shape and sizes have been affected over the last several hundred years.
What researchers found was that the average American head (males) today is eight millimeters (0.3 inches) taller from the base to the top of the skull, while skull size grew by 200 cubic centimeters, approximately the size of a tennis ball.
According to the Universities Lee Jantz:
“The varieties of changes that have swept American life make determining an exact cause an endlessly complicated proposition.”
Jantz further revealed to HealthDay:
“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.”
Women have also experienced increases with skull height up by seven millimeters and skull size increased by 180 cubic centimeters.
When you examine head size against other height increases the human American skull is 6.8 percent larger than the 1800s while our body height is up 5.6 percent and our femur (thigh bone) is up just 2 percent.
The research also found that our skulls are maturing faster with a major bone structure closing at 14 years old in girls and 16 years old in boys, down from an average of 20 years old compared to earlier skulls.
While researchers can not be certain yet of the effects the maturing brain has on humans they believe it could be tied to increasing childhood obesity rates as hormones that alter growth and maturation change in how they operate.
The study has not yet been published in a peer-reviewed medical journal.