By Tom Jacobs

Why do humans play, and listen, to music? The question has long baffled evolutionary theorists. Some suggest it had its origins in courtship rituals, while others contend it had (and has) a unique ability to bond people together to work toward a common goal.

Now, a couple of Harvard University researchers have proposed a new concept: They argue that the earliest music — and perhaps the prototype for everything from Bach to rap — may just have been the songs mothers sing to their infants.

Maybe the first musical genre wasn’t the love song, but rather the lullaby.

“The evolution of music must be a complex, multi-step process, with different features developing for different reasons,” says Samuel Mehr, who co-authored the paper with psychologist Max Krasnow. “Our theory raises the possibility that infant-directed song is the starting point for all that.”

Mothers vocalize to their babies “across many, if not all, cultures,” the researches note in the journal Evolution and Human Behavior. Its ubiquity suggests this activity plays a positive role in the parent-child relationship, presumably soothing infants by proving that someone is there and paying attention to them.

In their admittedly speculative thesis, Mehr and Krasnow write that infants intuitively understand the importance of such attention, and are unhappy when a parent turns away to attend to other matters (including another child). They want the focus to be back on them, and often will cry until they once again have it.

Singing, the researchers argue, is a particularly powerful way to reassure infants that mom or dad’s focus is on them. Unlike simply holding a child, singing requires concentration and attention; often, a parent will adjust the volume or rhythm depending on the baby’s responsiveness, or lack thereof.

In other words, if you’re being sung to, you feel safe. And safety is one of our most basic needs. A child who is being watched carefully is less likely to get into trouble, and more likely to survive and pass down its genes to another generation.

If music really did begin with these sing-song vocalizations, “adult responses to music should correlate roughly with infant responses,” the researchers write. This idea “is supported by some preliminary evidence. Neural signatures of pitch processing mechanisms are comparable between infants and non-musician adults, and, like adults, infants spontaneously engage in physical motion in response to music.”

Such as tapping your toes.

The theory does not explain how we got “from lullabies to Duke Ellington,” as Mehr puts it. But it does suggest a plausible starting point.

Some important thinkers have concluded that music serves no evolutionary purpose, including Harvard psychologist Steven Pinker. He isn’t at all sure this new theory is correct, but he calls it “the first explanation that at least makes evolutionary sense.”

To quote the great songwriting team of George and Ira Gershwin, perhaps music grew out of one of our deepest needs: “Someone to Watch Over Me.”

Via