Humans are the second fastest driver of biosphere degradation in Earth history but we could become the fastest driver of positive biosphere change ever seen

Earth’s biosphere has been subject to both transient and persistent disruptors throughout its history. Transient disruptors, such as large igneous province volcanism and asteroid impacts, are typically short-lived (<1 Myr) agents associated with temporary but sometimes massive loss of biomass and biodiversity. Persistent disruptors, such as the evolution of land plants, typically operate over long timescales (>50 Myr) and have ultimately enhanced planetary habitability with new ecosystems and symbioses, even when they caused harm to the incumbent biosphere. Here we examine anthropogenic impacts on the biosphere within the framework of past transient and persistent disruptors.

Recent human activity has been degrading Earth’s biosphere at a greater rate than any previous disruptors in Earth’s history except for the Cretaceous-Palaeogene (K-Pg) mass extinction which was caused by an asteroid impact. In particular, we show that the rate of recent biosphere losses in terms of biodiversity and naturally available (versus human-appropriated) biomass and primary productivity are on par with or exceed the rates of almost all past mass extinctions. Moreover, human business as usual is expected to continue and potentially increase the rate of biosphere degradation over the next century and millennium. 

However, humans have the capacity to choose the nature of our impacts on the biosphere. We have the potential to be a persistent disruptor of the biosphere by consciously choosing interactions that increase biodiversity and naturally available productivity. This can be achieved through a combination of new technologies and place-based understanding of the natural world developed by human societies globally over thousands of years. From Mediterranean savannahs to Pacific Island fisheries, to Australian and American deserts, humans have enhanced local and regional biodiversity and biomass without appropriating the bulk of it for ourselves but instead sharing it sustainably with the non-human biosphere.

We are the first disrupting agent able to make conscious choices about our impact on planetary habitability. By comparison with the geological and fossil records we show that most contemporary anthropogenic impacts on the biosphere resemble those of past transient disruptors, which at a global scale are degrading wild biomass and biodiversity through climate change, habitat loss and predation. Despite this, near-future humanity has the capacity to be a persistent disruptor of the biosphere, increasing biodiversity and naturally available biomass and productivity, by drawing on both emerging technologies and past and contemporary human experience. Evidence from past disruptors deep in Earth’s history inform the intentional changes to human-biosphere interactions that are needed for us to enhance planetary habitability in the near future.