What is the evolutionary pressure that would drive us to evolve a brain we only use 10% of?

The 10% brain use idea is a complete myth. We in fact use nearly 100% of our brain, just not all at the same time. Go ahead and Google it. You'll find that you are clinging to ignorance.

We don't only use 10% of our brain. We use it all, but some parts are specialized and we don't use them all at the same time, like the part that controls balance or vision.

Its the human characteristic of laziness caused by a comfortable environment. Most people seem to have "moved out" of the 90% where kindness, consideration, and compassion reside.

"Use" is a deceptive term anyway, there are all sorts of things going on in there. Dont forget your subconcious, the minds operating system, maintenance, body function control, memory, and all the filtering of your senses. It isnt just one app running! All in all it seems to be pretty packed in there.

Just because your head hasnt exploded yet doesnt mean your not using all your brain.

There's no evolutionary pressure that could ever, possibly do that. We use 100% of our brain. Whoever made up the myth knew nothing about biology or thermodynamics. If we don't use it, we lose it.

When humans suffer brain trauma they start to use parts of that excess. Why do you bring 10 pairs of socks on vacation and then only wear 10%?

There are no brain stores in the jungle to buy a new one, so we carry vestigial brain matter.

It doesnt take an evolutionary pressure for that.

It takes social pressure or peer pressure.

If youre being abused every day by morons you will either brake out or you will blow your brains out.

Necessity is the mother of evolution.

Evolution can happen at any time at any place.

The 10% thing is a myth. We actually use just about all of our brain at one time or another. 10% seems to be referring to how much we use typically, at any one given time.

Your brain has a lot of extra volume in case of a trauma or injury then one can keep on functioning if part of it is lost.

We use all of our brain, not all of it at the same time though. Only about 10% of our brain is active at any given time.

That means! we all really don't know anything and will follow what this crazy world feeds us.