On Facebook yesterday, Science Alert posted a picture of a cute little piggy. Why, they asked,
do humans feel such love for baby animals? Assuredly, this is a psychology experiment waiting to happen!
Not so. For one of my favourite science writers beat them to it, by about 30 years. And in a rather entertaining manner. In an essay originally published in Natural History, Stephen Jay Gould approached this question via a discussion of ... Mickey Mouse!
For Mickey, you see, started life as a much less lovable character than he is today. Gould describes him as a "rambunctious, even slightly sadistic fellow" when he first appeared in the film Steamboat Willie. And Mickey had a face to match the personality, with a longer nose, smaller eyes, and much lower forehead that he does today. But over time, "the blander and inoffensive Mickey became progressively more juvenile in appearance" - in other words, he was neotenised :) And in his essay A Biological Homage to Mickey Mouse, Gould asked, why? Why would the Disney artists have made these progressive changes to the famous rodent's appearance?
As Gould points out, the German ethologist Konrad Lorenz first suggested that the morphological differences between adults and babies provide significant behavioural cues, with child-like features triggering affectionate responses from most adults. Lorenz characterised these features as innate releasing mechanisms, which included a head that was relatively large compared to the body, large eyes, a bulging cranium, & chubby cheeks. Of course, the fact that baby animals (for example, Science Alert's little pig) also have these features has absolutely nothing to do with causing humans to view them affectionately (although we often do).
So, Gould suggests, the Disney artists - consciously or unconsciously - drew Mickey as more 'child-like' in order to evoke an affectionate response - however biologically inappropriate - in those viewing their movies or reading their comics. (After all, an unlovable protagonist was hardly likely to inspire people to keep on buying tickets or books!)
Gould concluded his essay by pointing out that humans, like Mickey, retain some childlike features into adulthood (& that has served us well):
A marked slowdown of developmental rates has triggered our neoteny. Primates are slow developers among mammals. We have very long periods of gestation, markedly extended childhoods, and the longest life span of any mammal. The morphological features of eternal youth have served us well. Our enlarged brain is, at least in part, a result of extending rapid prenatal growth rates to later ages. (In all mammals, the brain grows rapidly in utero but often very little after birth. We have extended this foetal phase into postnatal life.)
I'm reminded on the quote that was on the whiteboard down at the Blood Service rooms, last time I donated platelets:
Growing old is mandatory. Growing up is optional.
S.J.Gould (1980) A Biological Homage to Mickey Mouse in "The Panda's Thumb: More Reflections in Natural History". W.W.Norton & Co.