In a new study published in PLOS Biology, researchers have discovered that human tears possess the remarkable ability to reduce aggression in men. This finding not only challenges the long-held belief that tears are merely for eye protection but also suggests that they play a significant role in human social interaction.The study was motivated by the long-standing mystery surrounding the purpose of human emotional tears. While Charles Darwin once thought weeping to be an incidental result of evolution, more recent research has indicated that tears could serve as a form of social chemosignaling – a way of conveying chemical signals...