Have you ever wondered why things suddenly get wildly popular? For instance, baby names and dog breeds.
In the 1950's, hardly any one named their daughter Jennifer or had an Irish Setter for a pet. But for no apparent reason, "Jenifer" began to get hot, and in 1961, it hit the tipping point and took off. Soon it was the most common girl's name in the United States. But the problem with sudden popularity is nicely summed up by the chorus of Jimmy Cliff's reggae classic: "The Harder They Come, The Harder They Fall." And as quickly as it rose, the popularity of "Jennifer" crashed. (Check out The Baby Name Wizard.)
The same thing happened to Irish Setters. The number of Irish Setters in American homes began to soar exactly at the same time and followed the same trajectory as the number of girls named Jennifer. The annual number of Irish Setter puppies registered with the American Kennel Club jumped from 2,526 in 1961 to 61,549 in 1974, and Irish Setters were suddenly the third most popular purebred dog in the United States. But then, just as Jimmy Cliff's song predicted, they crashed. In the mid 1980s, registrations plummeted to their pre-boom levels.
Irish Setters were not the only dog breed to show this sudden spike in popularity. Since the 1950s, nine other breeds have shown the same pattern, including Old English Sheep Dogs, Dobermans, Rottweilers, and, of course, Dalmatians.
What's going on? Why should thoughts like "I want to name my kid Jennifer!" and "I want an Irish Setter!" suddenly sweep through the heads of Americans?
The Largest Data Set In the History of Psychology
It turns out that rapid fluctuations in the popularity of baby names and dog breeds shed surprising light on an important question -- what causes massive changes in a culture? I became interested in this issue when the American Kennel Club kindly provided me with the number of annual registrations for every AKC recognized breed between 1926 and 2005. With a current total of 54 million dogs, this is probably the biggest data set in the history of psychology. (If you have an AKC-registered dog born before 2006, it is represented on the computer in my office.)
As I recount in my new book, Some We Love, Some We Hate, Some We Eat: Why It Is So Hard To Think Straight About Animals, I figured there was important information hidden among the gazillion registration numbers the AKC sent me. But the truth was that I had no idea how to look for patterns or even what questions to ask. Then one afternoon I stumbled on an article about baby names.
The authors were Alex Bentley, an anthropologist, and Matt Hahn, a quantitative geneticist. They were applying a theory of biological evolution called random drift to shifts in popular culture, in this case, what people name their children. While the math is complicated, the idea is simple. The conventional Darwinian view of evolution is that genes associated with traits that are in some sense "better" will increase an individual's reproductive fitness and thus be more likely to be passed on to the next generation. The random drift idea, in contrast, is that some genes will spread through a population just by dumb luck, as long as they are not deleterious.
While I could not understand the intricacies of the mathematics in their paper, I did get the basic idea: shifts in a society's tastes - be they for baby names or cool sneakers - are often attributable to a combination of chance and our tendency to unconsciously copy what other people are doing.
Hmm...would these guys be interested in working their computer magic on 54 million dog registrations?
I dashed off an e-mail and had their enthusiastic response an hour later. "Send us the file!"
These guys work fast. I sent them the AKC registration numbers on a Friday, and we had the answer on Monday morning.
What We Learned From Purebred Dog Registrations
First, just as they suspected, Alex and Matt found that whether or not a dog breed gets popular is largely a matter of luck. Most dog breeds never go anywhere, including some breeds that would make great family pets. On the other hand, even breeds that are more "difficult" sometimes hit the big time. Bulldog registrations have gone up recently despite the fact that they suffer from dermatological problems, sleep apnea, and the tendency to slobber, snore, fart, and drop dead from cardiac arrest. (Note that this is not the same breed as Pit Bulls.)
Second, at any given time, only a handful of breeds are really popular. As is the case with baby names, dog registrations conform to a swooping line that statisticians call a "power law." For example, in 1970, half of the roughly one million new registrations were accounted for by just four breeds. And in 2007, the most popular breed (Labs) had 9,000 times more puppies registered than the least popular breed (English Fox Hounds).
Third, the role of the media in instigating fads in baby names and dog breed is over-rated. True, a few Disney movies have produced a temporary spike in a breed's popularity (think English Sheep Dogs and Dalmatians). However, there are hundreds of dog movies, and most of them do not produce an explosion in the demand for puppies. Further, the social psychologist Steve Elias and I found that, contrary to conventional wisdom, dog breeds that win the annual Westminster Dog Show in Madison Square Garden do not usually show a subsequent spike in popularity.
How We Choose Our Animal Companions
Here is the take-home message. Our studies of shifts in dog breed popularity over the last eighty years reveals that our choices in canine companions are based less on a rational consideration of the pros and cons of a breed than the same herd mentality that determines what we name our kids and the latest in tattoo fashions. Ouch!
References - The ratings are adapted from the White Water Rapid Difficulty Scale, from Class I (easy and fun to paddle or to read) to Class V (warning: serious possibility of brain injury!).
1. My new book: Some We Love, Some We Hate, Some We Eat: Why It's So Hard To Think Straight About Animals (Class I)
2. Article on dog breeds and cultural evolution (Class V).
3. Article on dog breeds as social epidemics (Class II)
4. Article on the effects of winning the Westminster Dog Show on breed popularity (Class III)
5. Article on the similarity between pop music, baby names and dog breed popularity. (Class V)
6. Willie Nelson's terrific version of "The Harder They Come".
Hal Herzog is Professor of Psychology at Western Carolina University and a Class III - IV kayaker.