Recent studies challenge the traditional notion that the emergence of complex life forms was heavily dependent on the availability of atmospheric oxygen. New research reveals that oxygen concentrations were sufficient to support complex life as far back as 1.4 billion years ago, suggesting that other environmental or biological constraints might have played a more significant role in shaping the trajectory of life on Earth.
The existence of complex life in oxygen-poor environments challenges the assumption that oxygen was the sole driver of evolutionary innovation, inviting researchers to explore other potential factors influencing the emergence and diversification of complex life forms.