Tuesday10 December 2024
delovoimir.com

Have you ever wondered? Here's why people have different skull shapes: scientists explain!

Western researchers have identified genes that influence the shape of the human skull, which enhances our understanding of evolution and the nature of certain conditions, such as craniosynostosis. However, this is not the only factor at play!
Задумывались, почему у людей разные формы черепов? Учёные объяснили это явление!

In 2023, researchers from the University of Pittsburgh and KU Leuven in the USA discovered 30 regions of the genome linked to the shape of the human skull. Analyzing over 6,000 MRI scans of adolescents revealed that most of these genomic regions were previously unknown. Additionally, the scientists identified other factors that influence head shape!

“It is known that genes play a significant role in the size and shape of the skull. However, our study is the first to demonstrate which genes are responsible for the typical features of head shape” Set Weinberg professor at the University of Pittsburgh Unsplash

A Deep Dive into the Study of the Human Skull

The 2023 discovery will aid in understanding human evolution and diagnosing conditions such as craniosynostosis, where the bones of the skull fuse too early, according to Western experts.

Unlike previous studies that were limited to simple skull measurements, American scientists utilized 3D models of the skull dome to conduct a detailed analysis.

Among the genes with a “global influence” is RUNX2, which is responsible for skull and bone development.

Interestingly, it was particularly significant to confirm that the genes affecting skull shape manifest similarly in individuals of European, African, and Native American descent.

Черепа неандертальцев (слева) вытянуты спереди назад, как американский футбольный мяч. Современные новорожденные (справа) и младенцы (справа) также имеют несколько удлиненные черепа, но к тому времени, когда человек достигает взрослой жизни, их головы приобретают форму, напоминающую скорее баскетбольный мяч / Neanderthal skulls (left) are elongated from front to back, resembling an American football. Modern newborns (right) and infants (right) also have somewhat elongated skulls, but by the time a person reaches adulthood, their heads acquire a shape more akin to a basketball /PHILIPP GUNZ/CC BY-NC-ND

Evolution and Head Shape

Researchers have also shed light on the differences between the skull shapes of modern humans and Neanderthals. DNA analysis showed that two fragments of Neanderthal genes are associated with a less rounded skull shape. These genes influence brain development and the formation of neural connections, which may explain subtle differences in motor skills and speech among people.

“The Neanderthal DNA preserved in us helps to better understand their brain and its functions” Toni Capra geneticist at Vanderbilt University

Interesting Facts About Skull Shape

  • Skull in Childhood

Newborns with soft skull bones are significantly prone to changes in head shape depending on their sleeping position. Prolonged lying on the back or one side can lead to a condition known as plagiocephaly, which results in an asymmetrical head shape.

  • Nutrition and Skull Shape

The development of the masticatory muscles, which depends on a person's diet, can influence skull shape. More intense use of the jaw muscles in childhood contributes to the increase in size and strength of the skull bones, while a soft diet, on the other hand, reduces the load on the muscles, leading to a smoother and more “refined” structure of the skull.

  • Skull Adaptation

Studies have shown that for individuals engaged in heavy physical labor or sports, the strain on the spine and neck affects the development of the occipital region of the skull. For example, ancient hunter-gatherers had more massive occipital bones than modern humans due to the frequent carrying of heavy loads.