What If Humans Evolved Backward?

Humans have been evolving for the past six million years. But something’s gone terribly wrong. And now we are evolving backward. Once this process began, how long would it take for you to become an ape again? What does climate have to do with it? And why would society completely collapse?

Thanks to evolution, humanity dominates Earth. But how did that happen? First, don’t think of evolution as a straight and narrow path. Evolution happens through the process of natural selection. Over millions of years, organisms adapt to their environments by developing the traits needed to keep them alive. The lifeforms that don’t adapt die. Evolution doesn’t have an end goal for you. It’s a never-ending process of survival. So if you started devolving today, how soon would humanity perish?

You know, climate and evolution go hand in hand. And with such extreme weather hitting the Earth, I’m looking at you, California, it’s hard to imagine what changes the next few thousand years will bring. Fortunately, we have some good news. That hole in the ozone layer is healing. The void was first noticed in the 1980s, and it’s expected to return to normal by 2045. Before celebrating, know this didn’t happen through good luck. That damaging hole is being repaired thanks to decades of environmental regulations and legislation like the Inflation Reduction Act. And we’re just getting started. By 2030, the IRA could reduce carbon emissions by 40%. We’re on the right path, so keep up the good work and stay focused. Our evolution and future as species are in your hands.

Your journey through devolution would eventually take you into a microscopic realm. It should take billions years for you to get there. But for the sake of our scenario, we’re going to speed this process up. Like way up. Let’s say, you raced through the backward evolution at the speed of one million years in one day. Before you shrunk out of sight, your body would stretch to new heights. That’s good news for my short kings out there.

In just one hour, you would grow to around 1.8 m (6 ft) tall. Your jaw and teeth would also expand, and your brain size would increase massively. Yeah, that melon of yours is getting huge. You just devolved back into Homo Erectus, humanity’s long-extinct cousin. And these changes would have major consequences on your life.

Another two minutes, and you’d lose your brain capacity. You’d forget how to hunt or farm. From now on, your diet would be limited. You’d eat whatever you could find in the wild. Or you could make a trip to a grocery store while they still exist. But you’d certainly wouldn’t be smart enough to understand how to pay. Clothes would be at a thing of the past now, you’d let everything hang free. You’d forget everything. You wouldn’t know how to bury the dead or how to create art. You’d be naked, hungry, kind of dumb and a little uglier. The good news? Nobody would tell you.

After about four hours into this experiment, you’d lose the ability to talk. And as you grunted your way through life, society around you would start to crumble. In the next 2.5 days, cities would be soon become abandoned ruins of a time forgotten. Instead of living in these buildings, you’d prefer roughing it in huts. Now you would devolve into Homo habilis, eating leaves, plants and whatever animal you catch. With your diminished brain capacity, you wouldn’t be able to use stone tools anymore. A warm fire would be a rare luxury.

After six days, you would devolve back into a chimp. You’d be living off the spoils of the jungle, eating seeds, nuts and insects. Over the next couple months, wild primates would reign on Earth again. After six months of your devolution, the lines between species would blur. Now you would live among the monotremes, mammals that lay eggs, like the platypus. Yeah, you would be hatched into this new world.

After one year, and you’d be wallowing in freshwater habitats with the other tetrapods. If that sounds refreshing, just wait. In one more year, you’d live it up as a starfish or worm-like creature floating in the ocean without care. The once great species known as humans would return to a single-celled bacteria 10 years into this wild experiment. All of human history, your knowledge and experiences would be gone, and you would be reduced to a tiny spec.

So once you’re back in this simple state, could you evolve back into a human again? Well, probably not. We humans evolved this way thanks to a lot of luck and specific circumstances. It all depends on the new conditions on our planet. You could develop blue skin like the Na’vi or even become bioluminescent. Maybe you would be just a pile of slime. Who knows?

Devolution is a fun theory, but it’s unlikely to happen like this. The situations that made your ancestors branch out from other species don’t exist to make this process happen in exact reverse order. It’s not like pressing rewind.