We all have been watching post-apocalyptic films, which tells the story of a catastrophe — an asteroid strike perhaps, or a nuclear war — that causes humanity’s demise, and then follows the challenge of remaining humans trying to save their species from extinction.

But what if human extinction is a looming reality? In fact, researchers around the world spend their days grappling with this very possibility, and how we might avoid it.

There are multiple theories around what might ultimately cause human extinction — everything from alien invasions to catastrophic asteroid strikes. But there’s a general consensus that some risks to human life are more plausible than others. Researchers have named them ‘existential risks’. An existential risk is not a regular hazard or threat. It’s the vulnerability is our inability to stop it from occurring and our exposure to that hazard.

Nuclear war

It is one of the biggest potential risks to human survival. This threat grows if countries produce highly-enriched uranium, and as political tensions between nations escalate. The risks are the effects of a large-scale nuclear winter — the period of freezing temperatures and limited food production that would follow a war, caused by a nuclear haze blocking sunlight from reaching the Earth — would be profound.

Pandemics

The misuse of biotechnology is another existential risk that keeps researchers up at night. One of the particular concerns is the abuse of biotechnology to engineer deadly, quick-spreading pathogens.

Climate change

Climate change — a phenomenon that’s already driving the decline and extinction of multiple species across the planet. The accompaniments to climate change — food insecurity, water scarcity, and extreme weather events — are set to increasingly threaten human survival, at regional scales. Imagine: food or water scarcity intensifying international tensions, and triggering nuclear wars with potentially enormous human fatalities.

Artificial Intelligence

Researchers philosophise that intelligent robots, unintentionally unleashed on the world, might impose widespread surveillance on humans, or outpace us physically and mentally.

Humanity itself

However wide-ranging these risks are, they all have one thing in common: humans play a key role in determining the severity of these risks. So what if humans are their own biggest extinction risk? Looking at past civilisations including the Roman Empire and Easter Island, the majority of existential risks are self-created, rooted in societies and the systems they produce.