Co-evolution of Life and Earth Challenges 'Great Filter' Theory

A new model challenges the 'great filter' theory, suggesting life on Earth evolved in step with geobiological conditions, not through improbable events. Researchers propose that key evolutionary milestones, such as the oxygenation of Earth's atmosphere, were not 'hard steps' but rather events that occurred when Earth's conditions were suitable. The team examined five milestones: the origin of life, the evolution of eukaryotes, oxygenation, complex multicellular life, and the arrival of Homo sapiens. They argue that the age of the sun and Earth significantly influenced the timing of these events. Geological and atmospheric changes, like cooling oceans and the development of plate tectonics, played a crucial role. This perspective shifts the focus from luck to the interplay between life and its environment, suggesting that the co-evolution of Earth and life may be a common phenomenon.