CHAPTER 4: Understanding past global changes to face future challenges

Abstract

Humankind is facing unprecedented climate and environmental crises with economic and social consequences that may compromise the development of our societies on Planet Earth. Changes in our Planet dynamics have played a determinant role in the evolution, migration and extinction of hominids and controlled the onset of sedentary societies, the development of agriculture and the Neolithic revolution, and the rise and fall of civilizations and empires. The history of the Homo genus is linked to the natural evolution of the Planet, although the detailed interplays of environment-climate-humans remain unclear in crucial milestones as the origin of bipedalism in the first hominids. the fate of Neanderthals, the onset of agriculture, the first cities and the Neolithic revolution, and the recent impact of humankind in the Planet owing to complex and often non-linear relationships. To design science-based policies for a fair and sustainable development of the societies we need to consider the long-term, natural evolution of Earth ecosystems and biogeochemical cycles and to understand the impacts at a planetary scale of the current climate change (Global Warming) and increased human pressure (Great Acceleration). To prepare as species and humankind to the planetary-scale challenges we need a complete knowledge and comprehension of our planet, an Earth-System strategy and vision and a time perspective that only geological records can provide.