Millions of Americans feed wild birds, especially in winter and spring. Studies show that this can influence birds' health and behavior in surprising ways.

Samuel Mehr has long been interested in questions of what music is, how music works, and why music exists. To help find the answers, he’s created the Music Lab, an online, citizen-science project aimed at understanding not just how the human mind interprets music, but why music is a virtually ubiquitous feature of human societies.