Hip-Hop and Rap Were the Real Musical Revolution, Not Rock, Study Suggests

The Beatles at JFK airport
The Beatles greet fans at JFK airport, New York City, on February 7, 1964.

The Beatles and the Rolling Stones, two groups often thought to have revolutionized music in the US, were merely jumping on the bandwagon of an already established trend, according to a recent study of American pop music.

The study found that it was the emergence of hip-hop and rap in the nineties that caused the biggest revolutionary shift in the modern history of pop music, rather than the explosion of rock music in the sixties.

Researchers at Queen Mary University and Kings College in London set out to track musical evolution using quantitative scientific analysis. Using samples from 17,000 songs in the US Billboard top 100 chart from between 1960 and 2010, the authors write that they studied the songs as a "fossil record", asking "questions a paleontologist might ask: Has the variety of popular music increased or decreased over time? Is evolutionary change in popular music continuous or discontinuous? And, if it is discontinuous, when did the discontinuities occur?"

By using big data analysis to sort songs into specific categories based on chord structures and tonal properties, songs were automatically grouped into "topics". The topics could then be tracked over time, to see how musical trends changed, diversified or converged.

Looking at specific revolutions in musical tastes, the researchers took the Beatles' first US number one, "I Want to Hold Your Hand," released in 1963 and thought to have sparked a rock revolution in US pop music, and set it in context with other songs also released around that time.

The researchers found there were already other popular songs with the same topic. "Their evolutionary trajectories were all established before 1964," the authors write, "Implying that, while the British may have contributed to this revolution, they could not have been entirely responsible for it."

And by following the trends, the researchers found that it was the emergence of hip-hop in the nineties, rather than rock in the sixties, that ushered in the biggest change in the popular music landscape.

Using this categorization, the authors could also track the rise and fall of entire genres. The "slow death of jazz" for example, was observed by the 75% drop in the occurrence of the topic synonymous with popular jazz acts between 1960 and 2010.

The least diverse era of music was in 1986, which the researchers attribute to the sudden popularity of drum machines and samplers. But they dismiss theories that music has become homogenized in recent years.

"Contrary to current theories of musical evolution... we found no evidence for the progressive homogenisation of music in the charts and little sign of diversity cycles within the 50 year time frame of our study," they write. "Instead, the evolution of chart diversity is dominated by historically unique events: the rise and fall of particular ways of making music."

"No doubt some will disagree with our scientific approach and think it's too limited for such an emotional subject but I think we can add to the wonder of music by learning more about it," said the paper's lead author, Matthias Mauch.

"We want to analyse more music from more periods in more countries and build a comprehensive picture of how music evolves."

The report's authors warn: "Those who wish to make claims about how and when popular music changed can no longer appeal to anecdote, connoisseurship and theory unadorned by data."