Life is so precious to us, and it is difficult to understand how that it could be taken away from us so abruptly. Well the chances that it could happen are very real, and they could effect us every day, but at some point, we have to expect that we won't survive some sort of event that could wipe away mankind. So here are five ways that our lives could end (within a hundred years).

1. Global Warming: Climate change is one of the biggest things effecting our planet right now, and it is very possible that it could very well cause such a change that humans simply could live on Earth anymore.

2. Overpopulation: Simple. We use up all the resources on our planet because we have too many people on planet.

3. Widespread Disease: Diseases travel in many ways, especially through the air. This makes diseases easier to spread, and increases our chances at being taken out by a disease.

4. Nuclear War: A scientist's worst nightmare is a worldwide nuclear war, which would take out a large chuck of the population almost instantaneously. 

5. Large Space Debris: A meteor killed off the dinosaurs, and there is a legitimate possibility that it could knock out the human race as well.

 Sources - http://www.businessinsider.com...

 http://www.livescience.com/369...