So last week the Nielsen ratings for 2014 revealed that jazz has become the least popular major musical genre for adults, falling behind classical music. Jazz accounted for 2% of all albums sold in 2014, or about 5.2 million albums. Which is only a bit more than the 4.5 million copies of the Frozen soundtrack album sold that year.

Music evolves. Jazz has existed for just over a century, and during that time it evolved rapidly, giving birth to forms like Dixieland, big band swing, bebop, cool, bossa nova, free jazz, fusion, and acid jazz. Jazz dominated popular music for a few decades, the 1920s-1940s, but since then has lived mainly on the fringes.

If we think of genres as groups of animals, then Classical composers would be like Mesozoic dinosaurs. They were huge in their day, and we can still admire their articulated skeletons in museums or orchestra halls, but the world they ruled is gone. They were eclipsed in the 20th Century by the mammals: hot blooded popular forms like blues, jazz, country, rock, soul, and hip hop.

I have long thought of jazz as being marginal but still alive and kicking. Maybe like marsupial music. Marsupials don’t rule the world, but hey, they’ve got Australia, and they had South America pretty much to themselves for a long time, and opossums have even managed to spread into much of North America.

But now I fear that jazz has become more of a monotreme. Back in the Jurassic, egg-laying mammals were the latest thing. But now there are just two major groups of monotremes: one species of platypus and around four species of echidna, confined to Australia and New Guinea. Monotremes are amazing, and well worthy of study and conservation, but they are pretty much an evolutionary oxbow lake, far from the mainstream. For the most part most people don’t even think about them.

Whichever depressing analogy is most fitting, marsupial or monotreme, jazz is well on its way to being a museum music: curated by music departments and Jazz at Lincoln Center, subsidized by festivals where the headliners are often anyone but mainstream jazz musicians, but nearly extinct in the wild.

This makes me sad, because I love jazz, and have spent many years listening to it and trying to play it.

I remember seeing the jazz band play at Taylorville Junior High when I was still in grade school. The long row of saxophones, shiny and gold, with strange bends and twists in the horns, and the music they made — I was hooked. I started playing saxophone soon after, and have tried to make progress on that horn ever since.

In 1982, the average age of the jazz audience was 29. By 2008, the average age had increased to 46. Jazz used to be music for younger people, but now its audience is about the same age as the audience for classical music, opera and ballet. A demographic status that doesn’t bode well for the future of any of these genres.

Music is always changing. Today’s music doesn’t sound like yesterday’s music. Part of that is due to cumulative culture: today’s music builds on yesterday’s music, and is written in response to it. Music also evolves rapidly as technology for making music changes. Beethoven couldn’t write for saxophone because it hadn’t been invented yet. Gershwin, Ravel and Prokofiev did write for saxophone, but by then mainstream Classical music was already ossifying, too conservative to fully admit this new instrument into its ranks. So the saxophone found its home in popular music instead, where  it reigned supreme for a few decades, especially the 1930s and 1940s, and lingered on as a popular solo break instrument into the 1980s. But saxophones have been superseded in popular music by more recent technologies: electric guitars in the 1950s and 1960s, then synthesizers in the 1970s, and later sampling and other electronic tools.

Another reason for the high rate of evolution in music may be its role in sexual selection. Back in 1871, Darwin not only invented the term “sexual selection,” but gave music as a likely example of it in humans.

it appears probable that the progenitors of man, either the males or females or both sexes, before acquiring the power of expressing their mutual love in articulate language, endeavored to charm each other with musical notes and rhythm. (Darwin 1871: 880)

Darwin thus argued that song in humans had much the same function as song in birds: attracting mates.

Unlike many songbirds, in humans both males and females sing and make other forms of music. Some people have argued that this is evidence against a sexually selected origin of music in humans. But song need not be produced by only one sex to be a courtship signal. In a number of bird species, both sexes sing, and duetting is important for maintaining pair bonds. See, for example, the duets of the wonderfully named happy wrens.

Nonetheless, in humans there seems to be a bias for males to be performing for female audiences. Analyzing a sample of 1,800 jazz albums, 1,500 rock albums and 3,800 classical music works, Geoffrey Miller (2000) found that

males produced about ten times as much music as females, and their musical output peaked in young adulthood, around age thirty, near the time of peak mating effort and peak mating activity. This is almost identical to the age and sex profiles discovered by Daly and Wilson (1988) for homicides, which they took as evidence for sexual selection shaping propensities for violent sexual competitiveness. (Miller 2000: 354)

The standard rock band basically looks like a lek, which Wikipedia defines as “an aggregation of males that gather to engage in competitive displays that may entice visiting females who are surveying prospective partners for copulation.”

In his book My Appetite for Destruction, Steven Adler, the founding drummer of the rock band Guns N’ Roses, tells a story about how in high school football practice he played especially aggressively to impress a particular cheerleader on the sidelines. He goes on to say that music is much the same thing for him:

I don’t know why I’m wired this way, but there are very few things in life that really light me up. And nothing focuses me or gets me going like chasing tail. Money, fame, status, power . . . nothing comes close to the pursuit of pussy. It gives me an intensity that brings out the fiercest side of my competitive spirit.

When I was with the band I had to score the best snapper after a concert. I loved parading around backstage and at the after parties with the pick of the litter. So whether it’s trying to score by making touchdowns or playing in a band, I love the ladies. Primo poon: accept no substitutes. (Adler 2011: 13-14)

In a lek, the pressure is strong to sound new, innovative, and distinctive. And like Milton Babbitt said, “Nothing gets old faster than a new sound.” So the pressure continues to come up with new and distinctive sounds.

In contrast, the average jazz jam session is sort of an anti-lek: a group of mainly male musicians playing old style music, not for a crowd of screaming teenage girls, but for almost no audience at all.

But even if music has its evolutionary roots in courtship signals, the beauty and power of music transcend those roots. You don’t need to be courting to appreciate the intricacies of a Bach fugue or the cunning way the melody navigates the chord changes of All the Things You Are. The strange power of music — the way we perceive particular combinations of sounds as beautiful or ugly or joyous or despairing — works regardless of whether we are in a mating mood or not.

Psychologist Mihály Csíkszentmihályi argued that “people are happiest when they are in a state of flow— a state of concentration or complete absorption with the activity at hand and the situation.” He frequently mentions playing jazz as an example of this. And maybe this is why I keep coming back to jazz. It makes me happy.

And in some ways, this is an amazing time to be a jazz fan. YouTube has hundreds of hours of music and video. Growing up, I knew jazz mainly from what we played in jazz band and what I could hear on late night public radio, tapes from friends, and the occasional album. I had only the vaguest idea of what any of these musicians looked like. I didn’t even know Miles Davis was black until Aunt Lynn gave me an album (Workin’ & Steamin’) with his picture on it. Now anyone with an interest and an internet connection can watch videos of jazz greats playing. There are websites offering detailed advice about how to play jazz. And I’ve been meeting younger players who really know their stuff.  So maybe there is hope this particular branch of music will stay alive, growing and evolving, even if the mainstream has long since moved on.

Adler, S. (2011). My Appetite for Destruction: Sex & Drugs & Guns N’ Roses. New York, HarperCollins Publishers.

Darwin, C. (1871). The Descent of Man and Selection in Relation to Sex. New York, The Modern Library.

Miller, G. (2000). Evolution of human music through sexual selection. The Origins of Music. N. L. Wallin, B. Merker and S. Brown, MIT Press: 329-360.