Biodiversity loss and its impact on humanity

Two decades ago the first Earth Summit raised the question of how biological diversity loss alters ecosystem functioning and affects humanity; this Review looks at the progress made towards answering this question. The 1992 Earth Summit in Rio de Janeiro, Brazil, stimulated an explosion of research into how biodiversity loss influences the processes that underpin the goods and services that ecosystems provide to humanity. That research has established that biodiversity is crucial for ecosystem function, but just how the relationship works has been a source of controversy. This Review considers recent advances that are beginning to explain how biological diversity influences the functioning of ecosystems, and the provision of specific ecosystem services. The authors conclude that, together with management strategies such as payment for ecosystem services, the next generation of biodiversity science has the potential to bring the modern era of biodiversity loss to an end and to maintain a satisfactory level of ecosystem services. The most unique feature of Earth is the existence of life, and the most extraordinary feature of life is its diversity. Approximately 9 million types of plants, animals, protists and fungi inhabit the Earth. So, too, do 7 billion people. Two decades ago, at the first Earth Summit, the vast majority of the world's nations declared that human actions were dismantling the Earth's ecosystems, eliminating genes, species and biological traits at an alarming rate. This observation led to the question of how such loss of biological diversity will alter the functioning of ecosystems and their ability to provide society with the goods and services needed to prosper.