What is the evolutionary purpose of getting nervous?

I had a job interview today for a part-time tutoring position. For part of the interview, I had to solve some algebra and math equations on a whiteboard. I was a little nervous, as I usually am at interviews, so I made a few stupid mistakes that I wouldn’t have made if I were doing the problems on my own.

This got me thinking. What evolutionary benefit is there to becoming nervous? Why would my genetic hardware include processes that put me at a disadvantage in crucial situations? It seems like humans would fare better if they remained cool-headed when a lot is on the line.

So you can run faster from the danger.

Fight or Flight reaction. You’re physically and psychologically getting ready to do one or the other.

Our ancestors didn’t have to deal with job interviews. They encountered situations everyday where a split second decision might mean the difference between life and death. Should they fight or run? Being in a heightened nervous state meant you had a better chance of surviving and leaving progeny.

As others have said, being in a heightened state of alertness (nervousness) put you in a state where you would be better able to flee for your life under threat, or to defend yourself from attack.

Since you were not actually under threat of death in this circumstance, the reaction was maladaptive. Our early ancestors never had to do algebra problems while being stalked by a sabretooth, so this reaction was not selected against. Your fearfulness in this case worked against your capacity for logical analysis, but this was a side effect, not an adaptive reaction.

It is a mistake to think that every reaction we have is adaptive in every circumstance, especially those that contrast greatly from the conditions under which they originally evolved.

I wonder if they’d have bothered with continuous survival if they had known it would en up with job interviews?

Tell me about it:

Basically, what others have said. If you have nothing but a short sword and are potentially facing a bear, lion, or a Legion, then being nervous might be a sign that you should consider whether or not you are really a match for your opponent. It could have saved your life.

Sword? That’s a highly advanced technological society with specialized professions and you very well might be faced with an interview.

More like a pointy stick in one hand and a rock in the other.

What if they’ve got raspberries?

I think a lot of nervousness comes from supressing the ‘fight or flight’ reaction. You can see this in dogs too when they are trying to be obedient in contradiction to their instinctive reactions.

The interesting part is that humans can create these situations entirely in their minds. There may be nothing threatening about the job interview situation except your own fear of failure. I wonder if any other animals suffer anxiety at the level humans do.