In his 1974 commencement address at CalTech, Nobel prize winning physicist Richard Feynman recalled a 1937 psychology experiment with rats in mazes. This maze was just one long corridor with doors on either side. The rat would enter from one side. He would then have to go to through one of the doors opposite to get to a chamber where food was placed.
The researcher (Paul Thomas Young) wanted to train the rat to go through the 3rd door to the right of whichever door it came in from. Instead, he found that the rat always went to the door where it had found food the last time.
Young painted the doors to be uniform, it didn’t help. He covered the corridor so the rat could not use the position of the room lights as reference, it didn’t help. He put chemicals to disguise the smell of the food, it didn’t help. He spread saw dust so the rat couldn’t recognize the way the floor sounded when they ran over it. Finally, he was able to get a series of conditions that were needed to fool the rat. If any of these conditions were relaxed, the rats could beat the experiment. Young had figured out all the conditions needed to run an experiment with a rat in a maze.
Unfortunately, this research went unappreciated. His results were considered of minor importance and researchers continued to use mazes the same way as before. The problem according to Feynman was that in the pursuit of startling results, researchers often tend to neglect the more mundane but necessary aspects that bring rigor to their work. This was the cause of the low reproducibility problem which continues to plague science.
Today, I came across a news item that researchers at the Edinburgh Zoo and the National Centre for Chimpanzee Care in Texas gave chimpanzees the option of listening to Beethoven, Mozart, Adele and Justin Bieber or just silence. This isn’t something new, playing music to captive chips is considered a way to enrich their experience.
But when the chimps got the opportunity to choose their own music, they didn’t show any of the behaviors one might expect from a human. For instance, they showed no preference for any musical types. In fact, extended observations led the researchers to conclude that the chimps didn’t distinguish between music and any other sound. The researchers concluded that playing music to captive chimps was unlikely to significantly enrich their experience.
Now there have been several studies about animals and music before. For example, in 2014, researchers at Emory University played Indian, Japanese and African music in different parts of their habitat for 40 minutes for 8 days. They found the chimps preferred areas with Indian or African music and avoided those with Japanese music or silence.
Although both papers are available online, one study does not site the other. In fact, the newer study does site some other references but then points out that in these cases, the chimpanzees did not have the option of choosing silence.
Further, the 2014 study used 2 groups one with 1 male and 9 females and another with 3 males and 9 females. The new study was on 18 animals. There are several problems in comparing the two works. Firstly, the animals used are different and relatively few in number. Try picking that many people at random and see their reactions to the same music. Secondly, the habitats where the chimpanzees were present are very different. Thirdly, the methodologies are very different and as the researchers pointed out, giving the chimp the choice of what to play can make a difference.
However, both studies were aimed at the same problem. Do captive chimpanzees appreciate music? The answer is, we aren’t sure.
Finally, there is the reporting problem. While both these studies are based on chimpanzees, both the BBC and the Express somehow extended the result to include all apes. Here is the Express headline: