Science journalist Lydia Denworth has written a book about the phenomenon of friendship and how the bonds we form with our friends are not just pleasant, but essential. She tells CBS News' Errol Barnett what she learned while researching "Friendship: The Evolution, Biology and Extraordinary Power of Life's Fundamental Bond." Denworth explains how studying baboons and other primates helped scientists understand the physical benefits of friendships — plus, why social media isn't as detrimental to our bonds as some might think.