Gaia 2.0. Could humans add some level of self-awareness to Earth’s self-regulation?

According to Lovelock and Margulis’ Gaia hypothesis, living things form part of a planetary scale self-regulating system that has maintained habitable condi-tions for the past 3.5 billion years (1, 2). In this concept, Gaia expanded from within the Earth system and came over time to alter the climate and dominate the surface cycling of nutrients. Gaia has operated without foresight or planning on the part of other organisms, but the evolution of humans and their tech-nology is changing that. Earth has now entered a new epoch termed the Anthropocene (3), and humans are beginning to become aware of the global consequences of their actions. As a result, deliberate self-regulation—from personal action to reduce carbon footprints, to global geoengineering schemes—is either happening or imminently possible (see the figure). We argue that making conscious choices to operate within Gaia constitutes a fundamental new state of Gaia. By emphasizing the agency of lifeforms and their ability to set goals, a Gaia perspective may be an effective framework for fostering global sustainability