ap7am logo
Logo Bar bseindia nse-india msn yahoo youtube facebook google thehindu bbc ndtv v6 ABN NTv Tv9 etv namasthetelangaana sakshi andhrajyothy eenadu ap7am bhakti espncricinfo wikipedia twitter

Human chin came from evolution, not chewing

Tue, Apr 14, 2015, 12:16 PM
Washington, April 14 , 2015: Our chins did not come from mechanical forces such as chewing but instead resulted from an evolutionary adaptation involving face size and shape - possibly linked to changes in hormone levels as we became more social, fascinating research indicates.

“Primates or the Neanderthals did not have chins. In some way, it seems trivial but a reason why chins are so interesting is we are the only ones who have them. It is unique to us,” said Nathan Holton who studies craniofacial features and mechanics at University of Iowa.

Using advanced facial and cranial biomechanical analyses with nearly 40 people, the team concluded mechanical forces, including chewing, appear incapable of producing the resistance needed for new bone to be created in the lower mandible, or jaw area.

Rather, it appears the chin's emergence in modern humans arose from simple geometry.

“As our faces became smaller in our evolution from archaic humans to today - in fact, our faces are roughly 15 percent shorter than the Neanderthals - the chin became a bony prominence, the adapted, pointy emblem at the bottom of our face,” Holton said.

Human chin is a secondary consequence of our lifestyle change, starting about 80,000 years ago and picking up great steam with modern humans' migration from Africa about 20,000 years later.

What happened was this.

Modern humans evolved from hunter-gatherer groups that were rather isolated from each other to increasingly cooperative groups that formed social networks across the landscape.
Agency: IANS
X

Feedback Form

Your IP address: 54.163.147.69