At first appearance, it makes no sense why animals play. When you're living on the fine line between life and death in the treacherous paradise that is the African wilderness, wasting resources with unnecessary energetic output just doesn't seem sensible. Evolution favours behaviours that help species survive and propagate, not fun. And yet, we do see play - and a lot of it - especially in young mammals. So, why do they do it?
Scientists studying play describe it as "any behaviour that does not have any apparent function". A more descriptive description is difficult, given that so many different species play and in such different contexts. Take ravens snowboarding, for example. In Alaska and Northern Canada, these Covids are known to slide down steep, snow-covered roofs, seemingly with no purpose at all. Once done, they'll climb back to the top and repeat the behaviour. Here in southern Africa, play is also evident from solitary elephants sliding along muddy riverbanks, to social play amongst groups of young lion cubs frolicking in the sand in their rough and tumble games.
For a long time, it's been assumed that play is a form of practice - most likely for hunting. Strangely enough, however, the research has never been able to back this theory up. Studies of Asian small-clawed otters with a propensity for juggling rocks were found to be no better at solving food puzzles that tested their dexterity and kittens surrounded by cat toys were shown to be no better at hunting in later life. So, while we might assume that a leopard playing with its dinner is practicing its own hunting skills for later life, the evidence just doesn't really seem to back this up.
But hunting isn't the only skill worth practicing. In observations from the field, researchers found 11 out of 12 orphans in a troop of baboons were adopted by another member (with the undesirable one luckily old enough to survive on its own). The most likely individuals to take over these responsibilities were the pre-productive females. This makes some sense, given that by increasing the likelihood that their relative survives they are indirectly increasing the number of their own genes in the gene-pool. But it's also been suggested that they are literally practicing for motherhood, to improve their own skills and ensure their own offspring get a good head-start to life when they are ready to have their own. Practice does make perfect, after all!
The next theory proposed is that play makes animals more psychologically flexible, but again the science doesn't really seem to back this up when it comes to advantages in problem-solving, creativity, intelligence or social skills in later life. Despite this, studies have shown that "young rats deprived young rats deprived of playmates grow up with less-developed prefrontal cortexes, a part of the brain deeply involved in social interactions and decision-making... These animals also tend to suffer deficits in short term memory, impulse control and the ability to notice or react to threatening gestures from other rats."
Whatever is or isn't backed up by science, it's clear that "without play, you're not as good at fighting, [and] you’re not as good at having sex, and you’re not as good at coping with a novel environment that you haven’t encountered before". As social animals, we rely on the cues that others give off to perceive their intended behaviour: a frown suggests something is wrong, while a smile suggests the opposite. Playing, and even make-belief play, expose you to these situations from a young age, letting you judge the true intentions of your playmate for the better of your future responses to aggressive or sexual encounters.
Whatever the science says, play is fun, and fun is good. Indeed, "studies show that wrestling rats enjoy a rush of dopamine and other brain chemicals that help to regulate emotion and motivation. The surge of dopamine, which activates the brain’s reward pathway, is especially intense in younger animals — potentially explaining why youngsters of many species are more playful than their elders." For most of the young animals pictured in this blog, on sexual maturity, they'll be cast out and left to fend for themselves. Play gives them the essential motor and social skills and tool-kits they will need to survive in these brutal, wild lands.
Thanks to this Inverse article for the inspiration.