Gaiahypotesen

The Gaiahypotesen, or Gaia hypothesis, proposes that living organisms and their inorganic surroundings on Earth are part of a complex, self-regulating system that maintains the conditions for life. Proposed by scientist James Lovelock in the 1970s, the hypothesis suggests that the Earth acts as a single, giant organism, or "superorganism," where biological and geological processes interact to stabilize the planet's environment. Key aspects of the hypothesis include the idea that life actively modifies and controls the atmosphere, oceans, and surface temperature to keep them within a narrow range suitable for its continued existence.

Evidence often cited in support of the Gaia hypothesis includes observations of how the Earth's atmosphere, despite being far from chemical equilibrium, has remained relatively stable over geological timescales. For instance, the coexistence of oxygen and methane, which would normally react and disappear, is seen as a product of biological activity that continually replenishes them. The regulation of ocean salinity and the maintenance of a relatively constant global temperature in the face of increasing solar radiation are also presented as supporting examples.

While the Gaia hypothesis has been influential in fields like environmental science and systems ecology, it has also faced criticism. Some scientists argue that the "self-regulating" aspect implies a level of conscious intent or teleology that is not scientifically supported. Others suggest that the observed stability could be explained by simpler ecological and geological feedback mechanisms without invoking a planetary-scale organism. Despite these debates, the Gaia hypothesis has spurred significant research into the intricate interconnections between life and the Earth's systems.