James Lovelock came up with a hypothesis that he named Gaia, which means The Goddess of the Earth, in Greek. This hypothesis claims that the Earth evolves, making it more livable, by doing things like controlling the climate, the elements in the atmosphere, and even the salt concentrations in the ocean.
Climate control is very important in order for life on Earth to survive. As each day passes, the sun becomes more and more hot. Lovelock claims that the Earth balances out this heat by doing things like creating more greenhouse gases, like carbon dioxide and methane gas. Methane gas can be produced a number of ways, but a very efficient technique is found in termites. Termites can be found in over two thirds of the Earth's surface. Termites eat wood and convert it into the methane gas when it is digested. Termites are the second largest source for the production of methane gas.
Lovelock also claims that the Earth controls the amount of oxygen that is produced at 21 percent. This is crucial because have too much oxygen would mean that forest fires would burn for much longer than now. Having below fifteen percent would mean that fire couldn't be sustained.
Many people don't agree with Lovelock and his hypothesis, but I believe that more and more people are coming around to it.