#4/15 What is energy?
How does planet Earth work?
Water and air molecules absorb energy by shivering and that makes them feel warmer to us. On the ocean surface, this can turn them into steam and it’s how rain forms.
Free energy will always be trying to warm things up. This is why ice usually melts, so it’s extraordinary that Earth can stay cool and we have polar bears!
In actual fact, if it wasn’t for plants and animals, our planet would quickly turn into a hot-house like Venus. Wildlife exists because it can behave in a way that keeps Earth cold. This is the fun bit to think about.
You exist because, together with all other animals, you are among the most likely community of organisms to stop Earth from over-heating. The Sun is the only source of energy for our planet and is constantly bombarding us but because of animals like us, we can create ecosystems. We hold back this tide.
It may surprise you to learn, that the coldest places on Earth create the most species. The only reason the poles have fewer animals than tropical rainforest is because animal diversity is removed by successive ice-ages.
Natural selection flows from cold to warm, while energy flows in the other direction. This is what maintains balance. The food you eat is energy that was captured by plants. By consuming this you are removing the threat of free energy escaping into the air and sea, creating chaos.
Humans and all other animals, are part of a big refrigerator.
