Many things have influenced our species’ evolution over the years, some much more than others. And while some would argue that some long ago practices were barbaric and that they should also be abolished today, a team of researchers from Harvard concluded that processed meat molded the course of human evolution.
Well, it wasn’t processed meat itself as much as the techniques and tools developed for processing meat. Still, if we never decided to start having an easier time eating the meat of the animals we caught, we might never have developed our current language skills and we might have even had more limited motor functions.
While over 2.5 million years ago hominids, our ancestors, were perfected chewing machines, a shift in our diets caused us to start changing. We started losing our huge teeth and jaws, as well as our powerful chewing muscles, and our mouths started getting smaller and our brains and bodies started getting bigger.
This shift paradoxically determined a need for a far higher energy intake, so we shifted to eating more meat. Scientists still disagree whether the increased number of nutrients came from eating more meat or from the invention of cooking. Still, jaws kept smaller and brains kept getting bigger.
Daniel Lieberman of the Harvard University in Massachusetts, co-author of the study had this to say:
So one big question is ‘What did humans do before they regularly had access to cooking?’ […] What we’re arguing really is that simple processing could have made possible the selection that we see in the fossil record for smaller teeth, jaws and chewing muscles. This kind of change could be beneficial for a variety of adaptations such as the ability to speak better, to have better language abilities… maybe better locomotor function (movement).
In order to test how well our current evolutionary form fares against various types of food eaten by those prehistoric humans, Lieberman and his colleague Katherine Zink performed an experiment in which they observed people chewing those types of foods – yams, beets, carrots, and goat meat.
The participants had to chew these foods in different forms – raw or cooked, whole, sliced, or pounded with stone tools, etc. As expected, the participants didn’t do so well at chewing raw and unprocessed meat, while the more processed and cooked the food got, the easier it was to masticate.
Concluding that not the meat itself but the processes used in preparing it had a huge effect in our evolution, Zink ended by saying the following:
What we found is that by simply slicing meat and pounding vegetables, a hominin would be able to reduce chewing effort by about 17 percent.
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