According to one theory, humans began to cook their food roughly 2 million years ago. This probably involved tossing the fruits of a hunt on a fire and calling it a day.

Now we can sit at the linen-covered table of a nice restaurant and select the exact cut of steak that we desire and the temperature at which it's cooked. We even have our choice of cooked veggies as a side dish.

Culinary skills have certainly come a long way, but scientists believe there has been a major biological change as well.

When food is cooked, it becomes softer. This means that it is easier to chew. Our early ancestors were able to dramatically decrease the amount of time they spent chewing, while still ingesting the same amount of nutrients.

Over time, their body (and brain) size was able to increase without wasting countless hours chomping away. The only parts of the body that seemed to shrink were our molars!

Read More:

• Chew on This: Thank Cooking for Your Big Brain (NewScientist)
• Evidence for a Tradeoff Between Retention Time and Chewing Efficiency in Large Mammalian Herbivores (ScienceDirect)

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