[marcinzm]

I wonder if reacting instantly to a command was also a positive survival skill when large trees could fall on you. People further away could see danger that you were too close to properly notice. If you didn't instantly do what someone said then you could end up dead.

[msrenee]

I thought about the survival aspect too. I'm a very jumpy person, especially when tired. I like to think it's due to heightened survival instincts. When I get surprised, there's often a 2-3 second period where I'm not consciously in control of my body. Usually all that happens is that I jump and take a couple quick steps the other direction before I come back into control. I have, however, found myself on the opposite side of a fence more than once and recently came around in position to vault a 5-foot tall barrier. During those few seconds, I've usually already identified who or what it was that startled me, but I'm not able to process that information or stop moving away. It's weird and a huge source of entertainment for friends, family, and coworkers.