When our distant ancestors discovered cooking it spurred an evolutionary step forward. Our brains grew larger and our stomachs shrank, and we were better able to walk upright.

Cooking food made a big impact because eating raw food is hard work. If you look at other primates they spend much of their life eating.

In 2008 scientists in the UK tried an experiment with humans, putting them in a zoo and feeding them as much raw food as they wanted: berries, fruits, vegetables, etc. To fulfill their daily energy requirements required eating more than 10 pounds of raw fruits and vegetables -- it was taking them most of their day to get through chewing this much food and most were unable to finish their daily ration.

By the end of the two week experiment it was clear that raw foods alone cannot fuel a modern human. All the test subjects lost lots of weight and they couldn't finish all of their food even though they would eat well into the night... some would have likely died if they had stayed on this diet.

Cooking food enables us to extract far more nutrition, and in a shorter period of time, than eating raw food. Cooking became an external stomach. And other techniques of food preparation gave similar results. For example, fermented foods make use of microorganisms to process and pre-digest foods for us, e.g. cheese, yogurt, wine, beer, kimchi, etc.

The discovery of cooking led to large changes in our physiology. Our stomachs shrank, our faces changed as our teeth became smaller, and the shape of our face became "modern" as our jaw muscles grew weaker and smaller.

Less time eating meant more time for other things: to develop social and other skills. We had more time to develop agriculture and create civilization.

Now we are developing another external organ: the brain. Our computers, in their many forms, connected by wires and wirelessly, are very much like an external brain. For example, I used to remember lots of phone numbers but now I don't -- I rely on my smartphone for that. I rely on my computers to keep track of many other things too.

And when I get really old, and start having serious lapses in memory, I will use Google image search to remind me of who I am talking with. And there will be many other brain aids available.

How will this external brain change us? How will it change our evolution? What will we look like in the future?

Our brains will likely shrink. They have been shrinking since the discovery of agriculture -- and that makes sense: we don't need the complex skills of hunter/gatherers in tracking animals, or recognizing plants and fruits; or navigating hostile conditions.

Similarly, the brain will shed those things it no longer needs to keep, like our bodies shed most of our hair, whittleing away at our little toes and fingers; the appendix...

As our gadgets become smarter we will become dumber but together we become greater.

And while we can't combine our real brains we can combine our external brains. That's already happening in the wave of the many collaborative applications and this is just the start of something much larger. What will that be like? What form will our future take? That's the ride we are on.

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Please see:

Did Cooking Make Us Human? | Watch Free Documentary Online

Amber Case: We are all cyborgs now | Video on TED.com

50 Posts About Cyborgs