Darwin (1872) proposed that facial expressions acquire evolutionary significance. Research has demonstrated that one emotion is more easily decoded in the faces of women while another is more easily decoded in the faces of men

Explain why the ability to decode these emotions would contribute to an early human's ability to survive and pass along that ability to offspring.
What will be an ideal response?

Answer: Happiness is more easily decoded in the faces of women, and anger is more easily decoded in the faces of men. Knowing that her partner is angry would be a useful skill for a female. She would know better when to approach him for things she needs, to ask for assistance, and to initiate sexual activity. Also, for males, knowing when his partner is happy would assist him with knowing when his sexual advances might be welcome and when her and the children's needs were fulfilled. All of these would increase the chance of procreation and the survival of offspring, making the ability more likely to be passed along as well.