There are few places left on Earth today that don’t bear evidence of human influence. It’s hard to picture what the world would look like without us here. But let’s imagine, for a moment, that all human beings suddenly disappeared. Poof! At the snap of a finger, we’re all gone, perhaps as a result of a huge natural disaster or nuclear warfare. What would happen to the planet we’d left behind? Well, experts have predicted the answer to this exact question, and it’s pretty fascinating. Let’s find out, step by step, what would is most likely occur in the event of human extinction.
1. Wildlife would reclaim previously human-dominated areas
First things first, there’s one big change that would occur pretty quickly once humans had disappeared from the Earth: wildlife would take over! Where once we had bustling city streets and human zones, animals and plants would swiftly move in to take them for themselves. Alan Weisman, author of the book The World Without Us, spoke to website Live Science about exactly how this would happen.
Weisman explained that insects would do well without humans, which, in turn, would “start a real cascade of events.” He claimed, “Once the insects are doing better, then the plants are going to do much better, then the birds.” Habitats would replenish, and slowly the creatures within them would move into our former neighborhoods.
2. Lawns, gardens, and farms would become overgrown
You’ve probably seen for yourself what can happen to an unmaintained lawn after just a few weeks during the summertime. To put it bluntly, it can grow out of control really, really quickly. Grass shoots up high, while weeds sprout everywhere. Imagine, then, what would happen if humans disappeared entirely.
With nobody cutting the grass and pulling out the weeds, gardens, lawns and farmlands would become messy tangles really quickly. There’d also be far diversity on that formerly strictly maintained land: different sorts of plants would be given the chance to establish themselves without being ripped from the earth.
3. Glass buildings would fall down, but others would stand for a long time
How would our man-made structures hold up after we’d disappeared? Would our buildings endure? Well, some are going to be standing for far longer than others. Glass buildings would be among the first to go, while metal ones would soon rust.
Stone buildings, though, would survive for a longer time. That’s an interesting thought, which Weisman put quite neatly. He said, “Buildings that will last the longest are the ones made out of the Earth itself.” Maybe there’s a lesson in that?
4. Roads and bridges would collapse
Our roads and our bridges won’t hold up forever without maintenance. Metal will rust and disintegrate, and plants will grow and ultimately weaken structures. It wouldn’t happen overnight, but over decades and centuries they’d become critically weakened.
Another point worth considering here is how much the surface of the Earth moves over time. That variation would create cracks on roads and bridges, which would only grow and become more severe without anyone to fix them up again.