With the planet heating up in more obvious ways, new models show that up to six billion people could be stranded in zones too hostile for humans by 2100.

It looks like our future is fewer humans, not more. And while that may be good for our long-term survival, it means rethinking our economic and political systems.

Anti-vaxers and alt med quacks are trying to convince anyone who'll listen that modern medicine is a sinister conspiracy to cull humanity.

Pundits are waking up to the fact that in the aftermath of the Great Recession, the youth of today is being set up for failure.

Could Earth's population be slowly but surely shrinking over the long term?

Today, extreme poverty is not an issue of insufficient resources, but of politics and allocation. And that makes it much harder to address.

There is a hard limit to how many people this planet can support, but we may never actually reach it. If we do, we could be quickly cut down to size.

A popular criticism of radical life extension is that society and life cycles would break down. But that's not what happens in organisms whose lives we dramatically increased in the lab.

Humanity is growing in number and we're starting to strain the planet and ourselves.