I have seen my guinea pigs mourn, and even become severely depressed after the death of their cagemates so I have no problem believing that humans can't be the only species that feel attachment and compassion. The following is a series of photos by a photographer chronicling the sad love story of a couple of barn swallows. It is said that people all over the world have cried after seeing these pictures, and that the French newspaper that originally ran the photos sold out on the day it first published the story. A female swallow became fatally injured after being hit by a car. Her mate brought her food and attended to her needs with love and compassion. He left to bring her more...