Is the Earth actually a living 'creature'? Chemical clues could finally prove claims our planet is a single organic system



'Gaia Hypothesis' claims earth is self-regulating 'organic' system that maintains life

Sulphur could be key to understanding cycles of Earth

Gaia idea initially scorned by scientists but now taken seriously

In the 70s, James Lovelock and Lynn Margulis claimed that Earth's physical and biological processes 'link' to form a self-regulating, basically 'self-aware' system

In the 70s, James Lovelock and Lynn Margulis claimed that Earth's physical and biological processes 'link' to form a self-regulating, basically 'self-aware' system.



Their book became a cult classic, and the idea that the Earth is a giant chemical system, almost like an 'organism' persists to this day - although it's never been proved.

In 2010, a poll of 400 academics placed the Gaia Hypothesis the sixth greatest British academic breakthrough of all time.



Now a new chemical clue - sulphur - could allow scientists to work out whether Earth is in fact 'alive' - a huge chemical system that in turn sustains us all.

The Gaia hypothesis doesn't claim that the earth is actually 'alive' - but that all living organisms and their non-living surroundings are bound together into a 'system' that maintains the conditions for life.

One of the early predictions of Lovelock's theory - known as the Gaia - hypothesis was that there should be a sulphur compound made by organisms in the oceans that would transfer to the air and thus to the land.

Scientists are on the brink of testing this theory - and proving the existence of at least one part of a 'system' of the Earth.



The most likely candidate for this role was deemed to be dimethyl sulphide.



Harry Oduro of the University of Maryland has created a tool for tracing and measuring the movement of sulphur through ocean organisms, the atmosphere and the land in ways that may help prove or disprove the controversial Gaia theory.



Sulphur, the tenth most abundant element in the universe, is part of many inorganic and organic compounds.

Sulphur cycles sulphur through the land, atmosphere and living things and plays critical roles in both climate and in the health of organisms and ecosystems.

‘Dimethylsulfide emissions play a role in climate regulation through transformation to aerosols that are thought to influence the earth's radiation balance,’ says Oduro, who conducted the research while completing a Ph.D. in geology & earth system sciences at Maryland and now is a postdoctoral fellow at the Massachusetts Institute of Technology.



Their book became a cult classic, and the idea that the Earth is a giant 'organism' persists to this day - although it's never been proved

IS THE EARTH REALLY 'ALIVE'? THE 'GAIA HYPOTHESIS'

The Gaia hypothesis - first proposed in the 70s - doesn't claim that the earth is actually 'alive' - but that all living organisms and their non-living surroundings are bound together into a 'system' that maintains the conditions for life.

It was initially scorned by scientists, but is now being seriously investigated by Earth scientists and scientists in other disciplines - observing how the evolution of life have contributed to the stability of temperature and ocean salinity.

It's also inspired various political and religious movements - with many interpreting the hypothesis as a claim that the Earth actually IS alive.

'We show that differences in composition of dimethylsulfide may vary in ways that will help us to refine estimates of its emission into the atmosphere and of its cycling in the oceans.’



As with many other chemical elements, sulphur consists of different isotopes.

All isotopes of an element are characterised by having the same number of electrons and protons but different numbers of neutrons.



Therefore, isotopes of an element are characterized by identical chemical properties, but different mass and nuclear properties.



As a result, it can be possible for scientists to use unique combinations of an element's radioactive isotopes as isotopic signatures through which compounds with that element can be traced.

‘Harry's work establishes that we should expect to see variability in the sulfur isotope signatures of these compounds in the oceans under different environmental conditions and for different organisms,' says UMD geochemist James Farquhar.