Did Neanderthals sing? Is there a "music gene"? Two scientists debate whether our capacity to make and enjoy songs comes from biological evolution or from the advent of civilization.
Music is everywhere, but it remains an evolutionary enigma. In recent years, archaeologists have dug up prehistoric instruments, neuroscientists have uncovered brain areas that are involved in improvisation, and geneticists have identified genes that might help in the learning of music. Yet basic questions persist: Is music a deep biological adaptation in its own right, or is it a cultural invention based mostly on our other capacities for language, learning, and emotion? And if music is an adaptation, did it really evolve to promote mating success as Darwin thought, or other for benefits such as group cooperation or mother-infant bonding?
Here, scientists Gary Marcus and Geoffrey Miller debate these issues. Marcus, a professor of psychology at New York University and the author of Guitar Zero: The New Musician and The Science of Learning and Kluge: The Haphazard Evolution of The Human Mind, argues that music is best seen as a cultural invention. Miller, a professor of psychology at the University of New Mexico and the author of The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature and Spent: Sex, Evolution, and Consumer Behavior, makes the case that music is the product of sexual selection and an adaptation that's been with humans for millennia.
Gary Marcus: We both love music and think it's important in modern human life, but we have different views about how music came to be. In Guitar Zero, I argued that music is a cultural technology, something that human beings have crafted over the millennia, rather than something directly wired into our genomes. Why do you think music is a biological adaptation?
Geoffrey Miller: Music's got some key features of an evolved adaptation: It's universal across cultures, it's ancient in prehistory, and kids learn it early and spontaneously.
Marcus: "Ancient" seems like a bit of stretch to me. The oldest known musical artifacts are some bone flutes that are only 35,000 years old, a blink in an evolutionary time. And although kids are drawn to music early, they still prefer language when given a choice, and it takes years before children learn something as basic as the fact that minor chords are sad. Of course, music is universal now, but so are mobile phones, and we know that mobile phones aren't evolved adaptations. When we think about music, it's important to remember that an awful lot of features that we take for granted in Western music—like harmony and 12-bar blues structure, to say nothing of pianos or synthesizers, simply didn't exist 1,000 years ago.
"An awful lot of features that we take for granted in Western music, like harmony, simply didn't exist 1,000 years ago."
Miller: Sure, and other things like the pentatonic scale and the verse-chorus-bridge structure of pop songs aren't as universal as most people think.
Marcus: I think it's deeper than that. Pentatonic scales are fairly common, but what we think of as music isn't what our ancestors thought of as music. Virtually every modern song revolves around harmony, but harmony is an invention that is only a thousand years old. Even if you ignore electric guitars and synthesizers, there is still some fairly significant difference between virtually all contemporary music and the music that people listened to a few thousand years ago.
Miller: A lot of music's features vary across cultures, especially in elite/pretentious music like Arnold Schoenberg, Indian ragas, or Chinese opera. But every culture includes singing, drumming, and dancing, and many aspects of folk music look fairly universal, such as rhythm, dance, pitch contours, scales, structural repetition, and timbre changes to express emotion
Marcus: When ethnomusicologists have traded notes to try figure out what's universal about music, there's been surprisingly little consensus. Some forms of music are all about rhythm, with little pitch, for example. Another thing to consider is the music is not quite universal even with cultures. At least 10 percent of our population is "tone deaf," unable to reproduce the pitch contours even for familiar songs. Everybody learns to talk, but not everybody learns to sing, let alone play an instrument. Some people, like Sigmund Freud, have no interest in music at all. Music is surely common, but not quite as universal as language.
Miller: Let's come back to the age of music. The bone flutes are at least 35,000 years old, but vocal music might be a lot older, given the fossil evidence on humans and Neanderthal vocal tracts. Thirty-five-thousand years sounds short in evolutionary terms, but it's still more than a thousand human generations, which is plenty of time for selection to shape a hard-to-learn cultural skill into a talent for music in some people, even if music did originate as a purely cultural invention. Maybe that's not enough time to make music into a finely tuned mental ability like language, but nobody knows yet how long these things take.
Marcus: Thirty-five-thousand years is certainly enough time to evolve some simple genetic tweaks like lactose tolerance, but lactose tolerances depends on just a few enzymes. Whether or not Neanderthals sang, music remains relatively recent in evolutionary terms, less than a 10th of a percent of the time that mammals have been on the planet.
Miller: What about the fact that responsiveness to music starts in the womb, and kids show such a keen interest in music?
Marcus: My best guess is that early interest in music is parasitic on language. We're born to listen for language, and music sounds sort of like language, so kids respond. But given the choice, infants prefer speech to instrumental music, and my lab's research suggests that they analyze language more carefully than music.
Miller: But most kids aren't passionate to learn about most purely cultural inventions, like chess or algebra.
Marcus: Lots of kids are passionate about chess, and even more about other cultural inventions like baseball and video games, to say nothing of Pixar videos. Video games, television shows, and iPhones are all cultural artifacts that were shaped to be irresistible to human brains, and that provoke strong emotions like music, but that doesn't mean that human brains were shaped to be attracted to them. I think of talented musicians as being like Steve Jobs: grand cultural engineers who design entertainment technology that appeals to brains that evolved for millions of years before the technology was developed.
Miller: So you're not much impressed that neuroscientists have identified some key brain areas that are active when hearing or performing music?
Marcus: Music is spread very broadly throughout the brain. There doesn't seem to be any part of the brain that is fully dedicated to music, and most (if not all) of the areas involved in music seem to have "day jobs" doing other things, like analyzing auditory sounds (temporal cortex), emotion (the amygdala) or linguistic structure (Broca's area). You see much the same diversity of brain regions active when people play video games. Face recognition has a long evolutionary history, and a specific brain region (the fusiform gyrus) attached, but music, like reading, seems to co-opt areas that already had other functions.