A study reveals that processing and eating meat paved the way for modern humans. The research was led by Katherine D. Zink and Daniel E. Lieberman, publishing the results online in the journal Nature on March 09, 2016.
Researchers saw an existent paradox in modern humans. The most important characteristic of our species is our brain. While other animals relied on power, human beings climbed to the top of the food chain using wits and intelligence. These characteristics require a big functional brain and at the same time, a brain like this requires proper food to function.
However, our species has a tiny mouth, tiny teeth and not a lot of strength behind our bite. How comes that we developed a powerful processor that needs a lot of calories and protein, but our bodies changed in a way that makes eating difficult?
“The origins of the genus Homo are murky, but by H. erectus, bigger brains and bodies had evolved that, along with larger foraging ranges, would have increased the daily energetic requirements of hominins. Yet H. erectus differs from earlier hominins in having relatively smaller teeth, reduced chewing muscles, weaker maximum bite force capabilities, and a relatively smaller gut” the article reads.
The researchers say the answer is meat. People tend to forget eating has an objective, to carry nutrients into the body. Today, we eat for pleasure, but earlier in history, all species needed an eating method that was simple and rewarding. Ingesting a lot of calories and nutrients without a lot of effort. By processing meat with stone tools, proto-humans gained access to a rich source of calories and proteins in a practical way. The researchers measured the effort in chewing cycles.
“We find that if meat comprised one-third of the diet, the number of chewing cycles per year would have declined by nearly 2 million (a 13% reduction) and total masticatory force required would have declined by 15%. Furthermore, by simply slicing meat and pounding USOs, hominins would have improved their ability to chew meat into smaller particles by 41%, reduced the number of chews per year by another 5%, and decreased masticatory force requirements by an additional 12%.” the article reads.
These changes in diet affected our physiology. Teeth grew smaller and smaller because the need of biting the meat out of the flesh and carcass was replaced by processing methods with stone tools. Big jaws and muscles were not necessary and more room was created for a bigger brain. Meat has more calories and proteins, so a lesser portion of it was enough to satisfy energetic needs making a big gut unnecessary. The benefits grew 500,000 years ago when cooking started to be a popular practice among proto-humans enhancing the benefits of both meat and USOs consumption.
Even though it is a theory, NATURE received it last year in August. After peer examination, they deemed it acceptable in January this year and allowed it to be published in the international weekly journal of science today. (NATURE).
Studies published by PETA have tried to prove that human beings are not meant to eat meat, but the results of this study might prove that not only meat is acceptable, but it also shaped proto-humans in what we are today.
Source Nature