Pop-science media can’t get enough of asteroids, super-viruses and nuclear holocausts. We are inundated on regular basis with speculative “science” stories about the various gigantic cataclysms that might cause human beings to vanish in the blink of an eye.
Most recently, the attention-getting headline “Could life on Earth end on March 16, 2880?” appeared, on the grounds that astronomers have charted the path of a large asteroid and computed that there is a 0.3 per cent chance that it will collide with our planet on that date.
It gets people all worked up. If you get enough politicians worked up, you can fund projects for “asteroid detection systems”. Stranger things have happened. And if you get the masses worked up, you can make blockbuster movies starring Will Smith or Bruce Willis and make millions of dollars.
Making predictions about spectacular catastrophic disasters is a cash cow for a number of reasons, not the least of which being that – as long as you place the doomsday date far enough in the future – you will never have to worry about people coming after you when you turn out to be wrong.
But none of these scenarios is actually very likely. If you set aside your adrenaline addiction, and actually think about the way that populations come and go on this planet – the way they always have done for billions of years – then it is actually quite obvious how humanity will end.
Unfortunately for Hollywood, it will be very slow, and very boring. It will not make a good movie.
Everyone loves the story about the extinction of the dinosaurs. It is dramatic, and it is easy to understand. There is a simple cause: a meteor. There is a spectacular effect: mass devastation, boiling oceans and continent-wide wildfires, followed by years of darkness because of the debris blown up into the atmosphere. It’s all very exciting, and the Discovery Channel seems to take an unholy delight in showing colorful animations of how it “would have looked” if we had been there to see it.
But although a large number of species died out in that event, that is not how most species in the history of this planet have disappeared. Most species have disappeared gradually. Most species died out because their environment slowly changed by minuscule amounts, over the course of centuries, gradually making food more scarce or predators more fierce.
Populations shifted, declined, and split up into smaller pockets scattered over wide areas until eventually, one by one, they simply disappeared.
We actually have some close cousins, anthropologically speaking, that this happened to: Neanderthal man. Neanderthals were well-established in Europe for a hundred thousand years, long before Cro-magnon man, the ancestors of you and me, arrived on the scene. They might not have been as smart as “full humans”, but they hunted and gathered and wore animal skins.
Over time, the climate changed. Africa experienced droughts, and Cro-magnon man wandered out of Africa and into Europe. But this wasn’t some kind of grand entrance that anyone noticed: it happened in small groups, wandering aimlessly northward, making their way in the wilderness. For thousands of years, Cro-magnon and Neanderthal men lived side by side.
But gradually, things changed. A volcano exploded in the Mediterranean, pushing tribes of early humans westward and northward and forcing them into smaller areas of land. Things got colder, which made everything more difficult for everybody. Cro-magnon had some tricks that Neanderthals didn’t have to deal with this: better tools, warmer clothing, and spoken language to help coordinate their hunts. So pretty soon the Cro-magnon tribes were warmer and more well fed, and the Neanderthals went hungry.
Over a span of more than 10,000 years, Neanderthal populations got smaller and smaller. They huddled into families and small groups, until one by one those groups – without drama and without fanfare – simply disappeared.
Think about what it was like to be a Neanderthal during that time. The changes are happening so slowly that at no point in your lifetime would it ever occur to you that your entire species might be “dying out”. You don’t experience any dramatic events. You don’t experience great change. During your lifetime, everything seems pretty much stable: you have a group you hunt and gather with, you occasionally encounter neighbouring groups.
Life is difficult, but it is roughly the same as it was for your parents, and their parents before them. During your lifetime, there would be no way that you would ever have knowledge of the fact that your species was in the process of a 10,000 year extinction event.
Playing the odds
It’s fun to talk about Neanderthal man as an example of this kind of process, because they were so similar to US. But that process of extremely gradual extinction is how most extinct species in the history of the world have died off. The story is the same for birds and mammals and fish all over the world. At this very moment, hundreds of thousands of species are in the process of gradually dying off; we simply don’t realise it, because they haven’t finished yet.
How will humanity die out? What is the most probable answer? Well, simple. The environment will change over the span of thousands of years. Things will become more difficult for humans, and their numbers will gradually decline. The change will be slow and unremarkable, but after ten thousand years or more, what it means to be a “human being” will change. Instead of mass overcrowding in soaring cities, it will mean small groups living in isolated pockets scattered across the globe.
What is considered “normal” by human beings will change. Populations will decline slowly, and scatter slowly. Eventually, it will be normal for individuals to never meet anyone outside their immediate family for their entire lives. They won’t think of it as weird, or as a sign of impending collapse: it will simply be the way life is. It will become part of what it means to be human.
And when that last family eventually dies, there will be no fanfare nor even a moment’s reflection on the extinction of mankind: they won’t even have known that they were the last ones left.