Life on Earth has existed for at least 2.5 billion years. Try as hard as you want, but that number is absolutely impossible for a human brain to comprehend because, of course, we never evolved to. The ability to comprehend small numbers was necessary for basic problem solving skills, and hence, Darwinian fitness. Comprehension of numbers in the billions, however, was not. And thus, evolution never bothered to give our brains that ability.
Over this incomprehensibly long period of time, life (which is, by definition, competitive) has evolved. Evolved not only on the level of individual species, but on the ecosystem level too. For example, pretty much every time a new species evolves, another one quickly follows, specifically designed by Mother Nature to eat the newcomer. Because biology is a dick like that sometimes, and by sometimes, I mean all the time.
Competition is fierce, with each and every living being ruthlessly pursuing the only goal that matters in this great biosphere: genetic perpetuation. As you can imagine, some incredibly clever technologies have been utilized for this purpose. From the cuttlefish’s incredible ability to hypnotize its prey through changing colors, to the adorable friendship/ murderousness of the coyote and badger, to downright dickishness of the golden eagle throwing its prey off a cliff, one need not look far to see evidence of evolution’s near infinite ingenuity.
But some Homo sapiens, in our near infinite arrogance, believe our kind to be above the reach of evolution’s influence. After all, this hypothetical person would argue that people across the planet are killing themselves slowly by following evolution’s incessant demands for stuffing sugar and fat into their faces, with no regard whatsoever for the health problems these foods will inevitably cause. In fact, he continues, the World Health Organization recently declared that obesity is now a larger global health crisis than hunger, all because evolution won’t adapt to the modern, Twinkie-obsessed world! What say you now, evolution man!?
Well, hypothetical person who clearly isn’t me, allow me to introduce you to evolution’s answer to the near infinite jiggly- ness of our asses. Meet brown adipose tissue, otherwise known as brown fat. Unlike white fat, whose primary purpose is to store excess food energy for later, brown fat is used by hibernating animals, as well as human infants, to generate heat, since natural selection tends to frown on parents who let their babies freeze to death.
Up until recently, scientists thought that most of our brown fat disappears after infanthood. As it turns out, however, research over the last decade or two has found that brown fat levels in human adults are rising. Of course, people who live in colder climates tend to have more of it, but the explanation for this trend is simple: Millions of years of eating mostly vegetables conditioned us to crave sugar like heroin (literally, many scientists now believe that sugar could be as addictive as some recreational drugs, but that’s another story for another day), and now that we’re eating enough of it to literally lower our evolutionary fitness, we evolved a way to harmlessly vent that excess energy.
That’s right; we as a species have actually gotten so fat, that natural selection had to step in and come up with a way to save us from our own never-ending demand for those sweet, sweet partially-oxidized hydrocarbons we call sugar. And now that evolution has started the job, scientists are hard at work trying to figure out how to convince our bodies to convert even more of that second piece of pie from last night into brown fat, rather than stored chemical energy that could be used to power our bodies, i.e. the whole reason we eat food.
So go ahead, eat that extra scoop of ice cream. Because if brown fat therapy ever actually becomes a thing, and lots of smart people are working hard to make it so, then you can literally say that the more sugar you eat, the hotter you’ll be.
Evan is the product of 85 million years of primate evolution. He enjoys sports, Star Wars, living in Cleveland and seeing the world as one giant science experiment with too many variables and not enough explosions.