1. Geography
A tree that quietly exists, never moving except to sway in the wind, yet endlessly conversing with the sunlight and the soil. Using sunlight and water and nutrient minerals to grow and change. But all done so imperceptibly, that to me the old oak tree on the green is the same as it was when I was a child." .
There is much evidence to back up his statement in his books, which he presents. He states that you can look at many aspects of the earth and see the homeostatis of the earth is very apparent, because all the organisms on earth help it be kept that way, or at least are supposed to. One way to see this is through the temperature of Earth. Lovelock writes that the surface temperature has remained pretty much constant. It's the heat from the sun that has gotten the earth a little warmer by twenty-five percent. .
Another way to see the Gaian Theory in effect is in, like stated earlier, the atmosphere of the earth. The earth's atmosphere consist of 79% nitrogen, 20.7% oxygen, .03% carbon dioxide with other gases such as methane. These gases are maintained that these percentages because of the living organisms on maintaing the homeostatis by using cycles found in our Earth. The nitrogen cycle is one of these cycles that help maintain homeostatis on Earth. In this cycle nitrogen sources (plants) are decomposed into the earth. It then makes a compost, which is further processed into ammonia and nitrites that bacteria can use to make nitrates. Nitrates can then be fed of to plants with fungi in there roots, and then are released into the atomosphere, or are then eaten by animals. The process then starts all over. Here is an ilustration to visulize it better. .
The oxygen cycles is a simple cycle which consists of plants and animals breathing. Animals breathe in the oxygen from the atmosphere to live and breathe out carbon dioxide into the atmosphere during the process of respiration.