The Gaia hypothesis was conceived by James Lovelock in the 1960s whilst he was working on NASA’s Mars Viking project. Lovelock was working on designing and making the instruments that would be used to search for and hopefully find evidence life on Mars.

During this project he had to first decide on what should be measured in order to find evidence of life. To solve this he envisioned himself on Mars looking at Earth and how could he tell that Earth was sustaining life. The answer was the atmosphere.

Planet Earth’s atmosphere has high levels of oxygen. Oxygen of which is being converted from carbon dioxide, via photosynthesis, by one organism to then be used by another organism to metabolise. Lovelock says that all these chemical reactions and processes make Earth’s atmosphere lively and possible to support life.

On the other hand, Lovelock describes Mars’ atmosphere as being almost dead; this inactivity led him to the conclusion that Mars probably doesn’t support life due to its atmosphere not showing evidence of any.

This led to a recommendation he gave to NASA about scrapping the Viking project as life on Mars was very improbable due to the atmosphere’s composition and inactivity.

 

This correlation between the atmosphere and life was the beginning of the Gaia hypothesis.

The name for the hypothesis, Gaia, was suggested by William Golding, a Nobel Prize winning author. The word originates from Gaea, the Greek goddess of Earth.

 

Lovelock came to meet a certain microbiologist called Lynn Margulis. She was the husband of one of Lovelock’s colleagues and, unlike her husband, she shared Lovelock’s belief in this idea of Gaia. 

Lovelock and Margulis co-authored paper, ‘Atmospheric homeostasis by and for the biosphere: the gaia hypothesis’. This was the first paper which properly introduced and started to explain the hypothesis, Lovelock did publish a brief paper on Gaia previous to this however.

‘The notion of the biosphere as an active adaptive control system able to maintain the Earth in homeostasis we are calling the ‘Gaia’ hypothesis, Lovelock (1972).’

The ‘biosphere’ is defined as “the regions of the surface and atmosphere of the Earth or another plant occupied by living organisms.”

This extract from the paper shows how the hypothesis has matured as Lovelock and Margulis have done more work and research into how the Gaia hypothesis works.

The hypothesis originally just stated that organic components had an effect, but it now states that the inorganic environment also plays its part in a biosphere’s self-regulating system.

 

The two early areas of research which showed promising evidence of how the Earth is self-regulating are the Sun & the oceans.

The Sun has been and will carry on to increase its heat output yet ever since the Earth has started supporting life, the Earth’s surface temperature has always managed to stay at comfortable levels to sustain life.

The concentration of salt in the ocean, salinity, stays low and consistent to support aquatic life, although large amounts of salt enter the seas and oceans every year. 

Both of these events that affect the biosphere have been made examples of to demonstrate that the Earth can and does self-regulate as a singular body as if the temperature and oceanic salt concentrations weren’t kept at similar levels then life would be lost and have subsequent effects on the rest of the Earth. 

There have been many studies to further provide evidence but also there have been smaller samples done on particular substances found in the water to give evidence of this regulation by looking at levels of chemicals and other substances in the ocean for example.

 

 

All organisms, especially humans, have an impact on the environment and the sustainability of a particular action or process, or lack of, can have major consequences.

 

The burning of fossil fuels for energy has many side effects that hinder the environment. The rate at which coal, oil and natural gas are being used is not sustainable, it takes millions of years for them to properly form from dead organisms. The human race are essentially burning through a finite resource without the means to replace the energy needs when we run out.

The burning of fossil fuels also releases harmful by-products into the atmosphere which can contribute to acid rain, which can causes serious harm and damage to the environment and its wildlife, and greenhouse gases which contribute to climate change. 

 

Deforestation is an incredibly unsustainable act. Large areas of the rainforests are being cut down for farmland. Deforestation affects the local and global ecosystem as it changes the water cycle, the makeup of our atmosphere and causes the loss of countless species of organisms.

The destruction of habitats and areas at this rate is not sustainable as the levels of replantation do not come close to the levels of deforestation.

 

Over fishing can quickly and negatively affect numerous ecosystems. The rapid reduction of one piece of the food chain can lead to a major imbalance. The organism that the overfished species would have preyed upon will increase greatly in numbers due to the lack of predators which can have a multitude of effects, for example this organism may release a potent toxin into the water supply. On the other hand, the organism which would eat the overfished species will decrease in numbers rapidly due to no longer having enough food to sustain their numbers, and depending on the food chain this could affect one or three other species.

 

Overpopulation is also becoming a pressing issue, not just for the human race but for the whole planet. There is already an imbalance where some people have access to everything they could possibly need whereas others do not have access to a bottle of clean water.

Overpopulation is not sustainable as the population is greater than one you can support with the resources you have. ��6�l�