How Sliced Meat May Have Driven Human Evolution (sciencemag.org)

sciencehabit writes: The most tedious part of a chimpanzee's life is chewing. Our primate cousins spend six hours a day gnashing fruits and the occasional monkey carcass — all made possible by the same type of big teeth and large jaws our early ancestors had. So why are our own teeth and jaws so much smaller? A new study credits the advent of simple stone tools to slice meat and pound root vegetables, which could have dramatically reduced the time and force needed to chew, thus allowing our more immediate ancestors to evolve the physical features required for speech. The abstract for the (paywalled) article is more informative than many.

Comments

Tooth longevity

[Anonymous Coward]

Surprised they didn't mention that a longer lasting tooth would have been a huge advantage as well:

"Slicing, whether with a knife or a sharp stone flake, changes all that. Suddenly, hominins could cut up the elastic muscles of a carcass into smaller bits before putting them in their mouths, making them chewable and easier to digest. Pounding has a similar effect on tough, fibrous root vegetables. “What we found is that by simply slicing meat and pounding vegetables, a hominin would be able to reduce the number of chews they use by about 17%,” Zink says. “That equates to 2-and-a-half million fewer chews per year.”

Imagine a 17% less worn tooth. Tooth loss is a huge disadvantage in the wild, just look at how desperate large predators get when they cannot hunt effectively.

An individual living 17% longer would be able to learn and pass on their knowledge and build a more effective society, perhaps even helping invent fire along the way.

Re:Beef Jerky is Devolution

[srmalloy]

Putting it in the bottom of a bowl before filling it with lobscouse will render it edible by the time you're down to it. Or you can pound it back to flour, mix it with suet and some leavening, and bake it again to make duff, or bag the dough and boil it to make pudding duff.

Cooking..

[thesupraman]

And the other small factor they missed.. Cooking!
Cooking has a large known effect on consumption and abduction of food. Especially meat. Resulting in needing to eat less quantity and being easier to chew..

No.. That couldn't be a factor.. Must have been those thin slices. Sigh.

Chewing cooked food is much much easier.. Making a larger difference than sliced meat (you don't think stone tools produce nice thin slices do you?)

Sounds a lot like someone flash of the moment idea that they rushed to publish rather than something with much backing

Does not make sense.

[140Mandak262Jamuna]

How old are the tools? Oldest things recognizable as human made tools are some 2.8 million years old. Tool use must be older than that but the tools they used were indistinguishable from ordinary natural rock. May be there were wooden tools too which did not survive.

All the hominids with robust skulls and jaws are that old. Tool use did not change the anatomy of hominids when they were invented.

Fire was tamed some 500K years ago. There was a gradual change, even Homo sapien neanderthalis had less robust skulls than previous hominids. That was 200K years ago. The Homo sapien sapiens, anatomically modern human beings, also 200K years had definitely smaller jaws and teeth. It was due to fire, not due to tool use. Homo sapien skulls changed from "robust" to "gracile" gradually over the last 100K years. Definite evidence having a strong skull as protection against random enemy bashing the head with a stone tool was not that important. They attribute this change to either language or culture being developed that allowed less lethal interactions between strangers.