Daisyworld: How the Earth Self-regulates Without God

Some years ago, the famous scientist James Lovelock proposed the Gaia Theory, which states that the Earth acts as a single organism, maintaining temperatures, oxygen levels, and so on within limits that support life – that allow life to flourish, in fact. He said that Earth acts as any living organism does to maintain homeostasis. This has caused considerable controversy, as how can the Earth ‘do’ anything? Many people claimed Lovelock was suggesting that a god of some sort existed to provide this control.

However, Lovelock used a very simple example to show that, whether or not God exists, s/he is not necessary to maintain Earth’s homeostasis: Daisyworld.

Daisyworld

Imagine an Earth with only two species of plants and no other life: Black Daisies and White Daisies. There is another key assumption: life occurs best within a certain temperature range. Warmer temperatures favour the white daisies, as they reflect heat away, while cooler weather favours the black daisies which absorb heat and thus stay warmer.

As the Earth orbits the sun, the distance between the two varies; the orbit is elliptical, not circular. As the Earth gets further from the sun, temperatures drop – and the black daises are favoured and spread, while the white daisies cede ground.

This change in balance also changes the amount of heat the Earth absorbs; more black daisies keep the Earth warmer, despite the decreasing heat from the sun. As the Earth’s orbit brings it closer to the sun, the reverse process occurs as white daisies spread and reflect more heat away from the Earth.

The key point here is not that certain conditions favour certain plants, a fact we know well. It is that life alters its environment to maintain the conditions for life. God doesn’t do it; that’s just the way life seems to work.

Lovelock pointed out that at some point in the Earth’s past, levels of oxygen stabilised at 21%, temperature fluctuations remained within tolerable limits, and so on. If life was simply random, this would never have happened.

The New Normal (You’re not in it)

Lovelock does not claim that life will maintain Earth’s current homoeostasis indefinitely for our benefit. In fact, he has spoken out strongly that we must act on climate change or we will push the Earth to a new homoeostasis that will not support most of the current life forms. What we are doing, in effect, is pushing the Reset button on Planet Earth; the system will reboot and most high-level lifeforms will be deleted permanently. Only some base lifeforms will survive; we will have reverted supercomputer Earth to a game of Pong.

While Earth’s life works powerfully (if unconsciously) to maintain comfortable  living conditions for all, we are overpowering Earth’s other lifeforms. We should be more respectful; if not for them, we would not have enough oxygen to breathe, crops would not grow, temperatures would be deadly, and so on. The difference between Mars and Earth is Life.

Life may not be God, but we should consider it sacred nonetheless, for without life in general, human life in particular would not be possible.

James Lovelock’s Library

Lovelock has written numerous books about Gaia, and all are worth reading. He has become quite convinced that humanity is doomed, not because we cannot respond to the climate crisis, but because we will not.

A final note: Lovelock is an independent scientist. He has funded his work through various means for decades – including corporate funding – and does not rely on government grants and university funding. He has been highly critical of the overspecialisation that occurs among scientists. Despite that, he is 100% in agreement with the worst-case scenarios for climate change, as he believes the science is unequivocal. (Note: The fourth book listed below is not Lovelock’s. He wrote the foreword and recommends the book.)