When a baby cries, any normal person nearby rushes over to help, encourage and comfort. There is an attempt to find the baby's needs, and meet those needs. I really believe that crying is not an evolutionary holdover, it's just an emotional holdover from infancy. When we have unmet needs, or need comforting, sometimes as adults we cry. This triggers those around us, especially those who love us but really anyone in the vicinity, to ask us if we are ok and attempt to comfort us or help us. We do it less and less though as we get older, except in extreme cases, like emergencies or deaths. Maybe it is because we as adults are the comforters now. Maybe it is because sometimes we cry alone, and no one comes to help, and so the behavior extinguishes. I never cry anymore, except when dealing with my parents,or problems i take to my parents. That, for me, is what proves my point. It is a hold over from my infancy, and there is still a vestige of it that my mind directs at my parents, for comfort.