Man is the only animal that blushes - or needs to.
Whoever blushes is already guilty; true innocence is ashamed of nothing.
I used to go red when anybody spoke to me. It's awful because you absolutely cannot control it. If you are a child that blushes, or is shy, the one thing you want in the world is to be the child who comes in and says, 'Hi,' to everyone and goes up and makes friends.
What is the evolutionary value of blushing? It seems not to be to our advantage to do it, to involuntarily reveal our inner emotions. If we're trying to manipulate or lie, actions in furtherance of individual goals as opposed to the goals of others, blushing would not seem to be helpful. And yet everyone blushes, except the psychopath.
The man that blushes is not quite a brute.