Multiple theories exist as to what might ultimately drive humans to extinction. But among those questioning the potential of humanity's demise, there's a general consensus that some risks to human life are more plausible than others.

Researchers call these "existential risks." Below are merely some samples, a few that both scientists and ordinary people have at the top of their minds. 

Pandemic

Unlike the ongoing coronavirus pandemic that's zoonotic in nature, what researchers fear is a man-made pandemic – the misuse of biotechnology. 

Cassidy Nelson, acting co-lead of the biosecurity team at the Future of Humanity Institute at the University of Oxford in the United Kingdom, says that what could possibly wipe out the human race is a pandemic that's a product of the abuse of biotechnology to create a fatal and quick-spreading pathogen. 

Nelson focuses on biosecurity issues that may endanger humanity, including biological weapons, pandemics, and infectious diseases. She says that specifically engineered contagious pathogen could be more fatal than a natural pathogen, and could cause the demise of most of the planet's population in a short amount of time. 

Nuclear War

The threat of a nuclear war has been portrayed in many films and novels, driving the belief that it is mankind's biggest risk to survival. But our vulnerability to nuclear war will only grow if countries produce highly enriched uranium and nations continue to pursue growing political tensions. 

A hard estimate of how much of the population would be wiped out after a nuclear firestorm is difficult to come by, but scientists believe that the effects of nuclear winter, the period that follows a war marked by scarcity of food and freezing temperatures, would be profound. 

Climate Change

What will kill off the human race is actually the accompaniments to climate change, which are extreme weather events, scarcity of water, and famine. But according to Luke Kemp, a research associate at the Centre for the Study of Existential Risk at Cambridge University, climate change is also an "existential risk multiplier." 

For example, water and food scarcity will result in international tensions, which could trigger nuclear wars and potentially wipe us all out form the face of the Earth. 

Humanity

The common denominator of all these risks is actually us, humans. We play a key role in the severity of all these risks. We are our own biggest extinction risk. 

Our fate here on Earth cannot be accurately predicted, but if we look into collapses societies of the past, a thing that's certain is that humans have never been better equipped when it comes to protecting ourselves.

However, what we can do is learn from the lessons of the past. Undeniably, the opportunity to learn is massive.