Problem:

Sweaty palms seems to be a reaction to stress, anxiety, etc. For our forest-inhabiting primate ancestors sweaty palms could cause unwanted side-effects such as slipping off tree branches under stressful conditions, like when being chased by a predator.

Required:

Question 1: Why did palm sweating become a reaction to fear, worry, anxiety etc in the course of human evolution?

Question 2: What is the benefit of sweaty palms?
Pleases explain.