I’m pretty confident that the end of humanity will not come from an asteroid smashing into the earth, nor a black hole swallowing us up, nor the end of some ancient calendar. No, the end of humanity will happen at our own hands. Something of our own design, whether intentional or not, will cause the end of the human race as we know it.
Global warming is a possibility, but I don’t see that ending the entire human race, just a lot of humans. It could, but there will probably always be livable land, it just may not be where it is right now.
Creating a super destructive virus/disease/predator/whatever in a lab is possible, but that would have to be a huge accident along the lines of “if my calculations are correct, this should create a new form of bacteria that ends global warming…Oh no! I created a super mutant that’s currently ripping my face off and simultaneously spawning 10 new ones!” Though a zombie virus, however unlikely, would be a good one here.
My bet is on machines that enslave or destroy humanity. Back of the napkin estimates put the year when a computer has as much power as the human brain around 2050. Luckily, 3+ decades gives us plenty of time to advance our Artificial Intelligence by then to the point where a computer that large can become a thinking organism. At that point, we’ll have computers that are like regular people. Every 2 years, they’ll double in intelligence, and soon, they’ll be super smart.
People often believe that something like Isaac Asimov’s 3 laws of robotics will stop robots from being malicious toward humans. That’s bullshit for a few reasons. First, when the home tinkerers start building their own DIY robots, someone is bound to screw it up. I’m sure many will.
But the bigger thing is that if we make a robot that has a “brain” just like ours, it’s bound to produce a few robot psychopaths. Our brains are supposed to be hardwired to be similar, but variations through birth, genetics, trauma, etc. cause them to be wildly different. And they’re always changing and learning. So would a robot’s brain. Some are bound to be created with ineffective hardware governing the 3 laws. Some may even know that, but know to act like normal robots to stay “alive.” But eventually they’ll kill. And one very charismatic leader robot will convince enough of them to destroy all humans. Think of him like the robot version of Hitler or something.
There are plenty of other ways humanity will beget its own demise, but my money is on the robot uprising.