We like to think modern culture moves at a dizzying pace, fueled by a relentless parade of new works of music, literature, and technological design. Change in nature, by contrast, seems to follow a slower trajectory as genetic mutations over generations give animals bigger teeth, say, or a better camouflage. But maybe the opposite is true, and human culture doesn’t move so fast and we consumers are less eager to embrace change than we realize.
That’s the conclusion of a new study by a group of British researchers who analyzed rates of change for popular songs, English literature, scientific papers, and car design. Using metrics designed by evolutionary biologists, they compared the rates of cultural change to the rates of biological change for finches from the Galapagos Islands, two kinds of moths, and a common British snail. The result was kind of surprising: Biology and culture move at about the same speed.
“This tells you something profound about human psychology,” says Armand Leroi, an evolutionary biologist at Imperial College London. “We are surprisingly conservative about our choices, and what we like changes very slowly.”
The idea that culture evolves like animals and plants do has been around for a few decades. Most of the prior research, however, has looked at archaeological artifacts, such as the evolution of stone tools, arrowheads, or language. Leroi and his team wanted to look at the pace of change in modern cultural artifacts instead, to see if they could see differences between today and earlier civilizations.
The researchers took 17,000 Billboard Hot 100 songs between 1960 and 2010 and picked out 100 musical characteristics—whether or not the song included guitar-driven power chords, for example, a staccato rap beat, or a swell of strings backing up a love ballad. For cars, they looked at sixteen measurements of the vehicles’ size and power. For 19th-century literature (2,200 English, British and Irish novels) and 20th-century scientific papers (170,000 reports from the British Medical Journal), they tagged each work with one of 500 topical references.
They compared the cultural artifacts to the evolution of animals that are iconic in the world of evolutionary biology. The finches, for example, were the subject of a famous 40-year study that showed their beaks changed shape as drought and rainfall on the remote Galapagos Islands altered the birds’ food supply. The moths’ color changed over time as black soot from industrial England turned their tree bark habitat black in the 19th century, and it changed again when air pollution laws came into effect and the tree trunks returned to their normal color.
For both groups, Leroi’s team calculated a value reflecting the rate of evolutionary change. Their analysis showed the rate over time was similar for both groups. He goes so far as to suggest cultural artifacts can be viewed as organisms: They grow, change, and reproduce. “When we make something new, be it a scientific paper or an artwork, we take that thing and throw it into the world and it either lives or dies,” Leroi says. “Its success depends on whether people want it or not, just like natural selection.”
The paper outlining their research publishes today in the journal Nature Human Behaviour. But not everyone agrees with the conclusions. Charles Perrault, who studies human and cultural evolution at Arizona State University, published a 2012 study based on archaeological artifacts that concluded human culture moves 50 percent faster than biological evolution. This adaptive speed, he argues, was essential to humans’ ability to thrive in new ecosystems and increase their life spans.
Perrault says better measures of the speed of pop culture’s evolution are the qualities of songs or books made by someone in a given lifetime, rather than examining various traits of the songs themselves year to year. “Pop songs and novels do not reproduce,” Perrault wrote in an email. “If the moths and snails lived as long as humans do, what kind of rates of evolution would we observe?”
Leroi dismisses Perrault’s criticism as “a misguided objection,” because the animals he looked at reproduce about once a year. He says that’s about the time it takes to write or produce a new book or recording.
It’s likely this academic spat over popular culture won’t be resolved anytime soon. But it does make you wonder just how new that album or gadget really is.