Do you prefer a diet with soft or hard foods? Prehistoric man chose soft food from 10,000 years ago with the development of agriculture. An unforeseen consequence was that the teeth changed as a result…
A third of the children have healthy teeth, another third absolutely need braces and another 33% are in between. In the Netherlands, no less than 45% of children receive braces. But why so many children have crooked and/or incorrectly placed teeth has long been a mystery. That conundrum has now been answered by Noreen von Cramon-Taubadel (University of Kent, England) in an article in the science journal Proceedings of the National Academy of Sciences .
Early farming
Agriculture originated in the Middle East about 10,000 years ago. In the millennia that followed, this phenomenon spread to Europe, among other places. Agriculture eventually arrived in the Netherlands about 8,000 years ago. The diet of the ancient Homo sapiens This changed:hunters and gatherers ate mainly hard foods including meat, while farmers ate softer, more plant-based foods. This required less chewing for farmers.
Measurement
Von Cramon-Taubadel wanted to know what the result was. She examined skulls from eleven present-day populations:six of them have diets based on agricultural and livestock products, and five populations mainly eat meat, fish, and collected items. These populations come from different parts of the world:from Japan to Greenland and from Australia to Italy. Von Cramon-Taubadel measured, among other things, the length and width of the jaw parts as well as other parts of the skull.
Diet
The diet had an impact on the shape of the jaw. The hunter-gatherers have a long, narrow jaw, while the farmers have a relatively wide, short jaw. In addition, the anterior part of the palate also appeared to have a different shape. According to Von Cramon-Taubadel, the differences between the two groups cannot be explained by differences in population location, climate and genetic history. This leaves two theories about how the jaw may have changed after the introduction of agriculture:children adapt the growth of their jaws to the softer food, or the jaw is already different at birth.
Finding young subjects to test the first option is obviously out of the question. However, an earlier study on hyraxes offers a solution. The jaws of young animals that ate softer food were found to grow more slowly. So, adjustment in childhood may be the answer.
One question remains:what about those crooked teeth? Chewing takes less time and is less intensive with softer foods. Because of this, the jaw grows more slowly than the jaw of hunters and gatherers. However, the teeth do not get smaller in the farmers, so they are cornered by the shorter jaw. This causes teeth to grow crooked and/or end up in a slightly wrong place. In the latter case, the occlusion of the teeth is no longer optimal.
The transition from hunter/gatherer to farmer 10,000 years ago therefore had major consequences for teeth. So it's no wonder that many children nowadays go to the orthodontist. Thus, the invention of agriculture may prove unexpectedly costly to today's parents.
- Evolution (Knowledge Link File)
- Poison tooth arises in the back of the mouth (Kennislinknieuws)
- Plants rather popular with prehistoric humans (Kennislinknieuws)
- Oldest human jaw found in Europe (Knowledge link news)