Planet Earth's nine lives: Our planet's limits
Tribes and nations
Humans live in tribes where people may, for example, look similar or speak the same language. These tribes have got really big and occupy large pieces of land. These enormous groups of related peoples and the land they live in have a name: 'states' or 'nations'.
The United States of America, the People's Republic of China and Russia are three really big nationsThe European UnionThis is a big group of nations which have agreed to act in partnership - though they still squabble. The trouble with nations is that they act selfishly in what they think is their own best interests. Although all the nations of the world have formed an organisation called the United Nations, this has little power to act in everyone's interests. So rich nations tend to grab much more than their fair share of everything and pour out much more than their share of pollution into everybody's air. Selfish or what? Because everyone suffers, especially the poor. It's very rare for nations to act together to fix global problems. But it has happened and has to happen much more.
And that's the reason for the scientists getting together to try and show that the planet's nine 'lives' and their limits are every nation's problem but no nation can solve them alone. The problems are really big but they can be fixed if only all nations work together to do it.
But most people don't even know - or accept - that there are problems.