When it comes to our planet’s climate, the impacts of the human population on the natural world are just as much a concern as the humans themselves.
So how much do we really know about the impacts on the ecosystem?
It’s been a bit of a challenge for scientists to answer this question.
The key point is that it’s been an open question for the past 50 years or so, and we now have a wealth of information about how many animals are in the world, how many people are in it and where they live.
But the key thing is we can’t just look at the numbers, because we don’t know the species composition of the world.
So scientists try to understand what the world looks like as a whole.
But, crucially, we don