A fascinating research indicates that 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.
"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.
Humans Existed 400,000 Years Before Than Previously Believed
A new study has revealed that humans existed 400,000 years before than previously believed.
Advertisement
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% shorter than the Neanderthals - the chin became a bony prominence, the adapted, pointy emblem at the bottom of our face," Holton said.
![Pre-Birth Exposure to High Levels of Testosterone Confer Evolutionary Advantages for Men]( "Pre-Birth Exposure to High Levels of Testosterone Confer Evolutionary Advantages for Men")
Babies who have experienced higher testosterone level in the womb are better at distance running, a correlation present in both sexes but stronger in men.
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?.
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. These more connected groups appear to have enhanced the degree to which they expressed themselves in art and other symbolic mediums.
Males in particular became more tranquil during this period, less likely to fight over territory and belongings, and more willing to make alliances, evidenced by exchanging goods and ideas, that benefited each and all. The change in attitude was tied to reduced hormone levels, namely testosterone, resulting in noticeable changes to the male craniofacial region.
One big shift was the face became smaller - retrenching in effect - a physiological departure that created a natural opportunity for the human chin to emerge. Children have flat, nearly imperceptible chins, much like what is seen in the Neanderthals. That bony prominence only becomes visible as our heads and faces grow into adulthood.
"Our study suggests that chin prominence is unrelated to function and probably has more to do with spatial dynamics during development," the authors concluded in a paper published online in the Journal of Anatomy.
Source: IANS
Pre-Birth Exposure to High Levels of Testosterone Confer Evolutionary Advantages for Men
Babies who have experienced higher testosterone level in the womb are better at distance running, a correlation present in both sexes but stronger in men.
Advertisement
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?.
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. These more connected groups appear to have enhanced the degree to which they expressed themselves in art and other symbolic mediums.
Males in particular became more tranquil during this period, less likely to fight over territory and belongings, and more willing to make alliances, evidenced by exchanging goods and ideas, that benefited each and all. The change in attitude was tied to reduced hormone levels, namely testosterone, resulting in noticeable changes to the male craniofacial region.
One big shift was the face became smaller - retrenching in effect - a physiological departure that created a natural opportunity for the human chin to emerge. Children have flat, nearly imperceptible chins, much like what is seen in the Neanderthals. That bony prominence only becomes visible as our heads and faces grow into adulthood.
"Our study suggests that chin prominence is unrelated to function and probably has more to do with spatial dynamics during development," the authors concluded in a paper published online in the Journal of Anatomy.
Source: IANS
Researchers Unveil Reason Behind the Divergence of Mammals Instead of Having Same Genes
Researchers led by European Molecular Biology Laboratory have revealed the reason of rich diversity in mammals.
Advertisement
 New Drug Proposal Could Revolutionise the Future of Alzheimer’s TreatmentA new proposed drug could be a huge step toward fighting against one of the leading causes of death: Alzheimer's disease. | Advertisement
|
Advertisement
Latest Research News
New study sheds light on the intrinsic, yet often overlooked, role of sleep preparation as a hardwired survival strategy.
Microgravity-induced bone loss in space, can be reduced by systemic delivery of NELL-1, a protein required for bone growth and its maintenance.
Researchers establish connections between Alzheimer's-linked genetic alterations and the functioning of brain cells.
Team at NeuroRestore introduces a groundbreaking gene therapy that has effectively promoted nerve regrowth and reconnection, post spinal cord injury.
Scientists aim to pinpoint particular functional pathways affected by these bacteria that may have an impact on skeletal health.
