If humans went extinct, what would the Earth look like one year later?
- Written by Carlton Basmajian, Associate Professor of Community and Regional Planning, Urban Design, Iowa State University
Home sweet home
Imagine that first year, when your house would sit unbothered by anyone.
Go inside your house – and hope you’re not thirsty, because no water would be in your faucets. Water systems require constant pumping. If no one’s at the public water supply to manage the machines that pump water[7], then there’s no water.
But the water that was in the pipes when everyone disappeared would still be there when the first winter came – so on the first cold snap, the frigid air would freeze the water in the pipes and burst them.
There would be no electricity. Power plants would stop working because no one would monitor them and maintain a supply of fuel[8]. So your house would be dark, with no lights, TV, phones or computers.
Your house would be dusty. Actually, there’s dust in the air all the time[9], but we don’t notice it because our air conditioning systems and heaters blow air around. And as you move through the rooms in your house, you keep dust on the move too. But once all that stops, the air inside your house would be still and the dust would settle all over.
The grass in your yard would grow – and grow and grow until it got so long and floppy it would stop growing. New weeds would appear, and they would be everywhere.
Lots of plants that you’ve never seen before would take root in your yard. Every time a tree drops a seed, a little sapling might grow. No one would be there to pull it out or cut it down.
You’d notice a lot more bugs buzzing around[10]. Remember, people tend to do everything they can to get rid of bugs. They spray the air and the ground with bug spray. They remove bug habitat. They put screens on the windows. And if that doesn’t work, they swat them.
Without people doing all these things, the bugs would come back. They would have free rein of the world again.
Armastas/iStock via Getty Images Plus[11]On the street where you live
In your neighborhood, critters would wander around, looking and wondering[12].
First the little ones: mice, groundhogs, raccoons, skunks, foxes and beavers. That last one might surprise you, but North America was once rich with beavers[13].
Bigger animals would come later – deer, coyotes and the occasional bear. Not in the first year, maybe, but eventually.
With no electric lights, the rhythm of the natural world would return. The only light would be from the Sun, the Moon and the stars. The night critters would feel good they got their dark sky back.
Fires would happen frequently. Lightning might strike a tree or a field[14] and set brush on fire, or hit the houses and buildings. Without people to put them out, those fires would keeping going until they burned themselves out.
Around your city
After just one year, the concrete stuff – roads, highways, bridges and buildings – would look about the same.
Come back, say, a decade later, and cracks in them would have appeared, with little plants wiggling up through them. This happens because the Earth is constantly moving. With this motion comes pressure, and with this pressure come cracks. Eventually, the roads would crack so much they would look like broken glass, and even trees would grow through them[15].
Bridges with metal legs would slowly rust. The beams and bolts that hold the bridges up would rust too. But the big concrete bridges, and the interstate highways, also concrete, would last for centuries[16].
The dams and levees that people have built on the rivers and streams of the world[17] would erode. Farms would fall back to nature. The plants we eat would begin to disappear. Not much corn or potatoes or tomatoes anymore.
Farm animals would be easy prey for bears, coyotes, wolves and panthers. And pets? The cats would go feral – that is, they would become wild, though many would be preyed upon by larger animals. Most dogs wouldn’t survive, either.
Like ancient Rome
In a thousand years, the world you remember would still be vaguely recognizable. Some things would remain; it would depend on the materials they were made of, the climate they’re in, and just plain luck. An apartment building here, a movie theater there, or a crumbling shopping mall would stand as monuments to a lost civilization. The Roman Empire collapsed more than 1,500 years ago, yet you can see some remnants even today[18].
If nothing else, humans’ suddenly vanishing from the world would reveal something about the way we treated the Earth. It would also show us that the world we have today can’t survive without us and that we can’t survive if we don’t care for it. To keep it working, civilization – like anything else – requires constant upkeep.
Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com[19]. Please tell us your name, age and the city where you live.
And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.
References
- ^ Curious Kids (theconversation.com)
- ^ curiouskidsus@theconversation.com (theconversation.com)
- ^ an associate professor of urban design (www.design.iastate.edu)
- ^ how much noise people make (education.nationalgeographic.org)
- ^ smog and dust that humans make (www.unep.org)
- ^ Boris SV/Moment via Getty Images (www.gettyimages.com)
- ^ manage the machines that pump water (wonderopolis.org)
- ^ monitor them and maintain a supply of fuel (theconversation.com)
- ^ in the air all the time (www.highlightskids.com)
- ^ bugs buzzing around (www.pestworldforkids.org)
- ^ Armastas/iStock via Getty Images Plus (www.gettyimages.com)
- ^ wander around, looking and wondering (sciencetrek.org)
- ^ was once rich with beavers (kids.nationalgeographic.com)
- ^ strike a tree or a field (kids.nationalgeographic.com)
- ^ even trees would grow through them (www.weekand.com)
- ^ interstate highways, also concrete, would last for centuries (kids.kiddle.co)
- ^ built on the rivers and streams of the world (damsafety.org)
- ^ some remnants even today (www.headout.com)
- ^ CuriousKidsUS@theconversation.com (theconversation.com)
Authors: Carlton Basmajian, Associate Professor of Community and Regional Planning, Urban Design, Iowa State University