Music is at least a million years older than language, yet we still see it solely through the lens of entertainment. Professor Michael Spitzer argues it's something closer to a biological system, one that was shaping the human body long before we had words for what we were feeling.

Why does a chord you've never heard before make you want to cry? Why do babies respond to rhythm before they've heard a single song? Why does the same part of your brain that processes mortal danger also process musical beauty? The answers reach back 4 million years, and forward into a future where music may be prescribed like medicine.

MICHAEL SPITZER: I'm Michael Spitzer. I'm professor of music at the University of Liverpool in the United Kingdom. I've written a book called The Musical Human, A History of Life on Earth. The past, present and future of music with Michael Spitzer. Part 1. The History of Music. How did you approach the history of music? People often write books in response to reading other books.…