Why nature's emergency is a problem for humans

The United Nations is warning up to one million different species of animals and plants are facing extinction because of human activity, and in a report is expected to say this biodiversity crisis is on a par with, maybe exceeds that, of climate change. But what is biodiversity? And why does it matter to humans?

This video has been optimised for mobile viewing on the BBC News app. The BBC News app is available from the Apple App Store for iPhone and Google Play Store for Android.