By Mark Lynas Updated 4:13 AM ET, Thu August 8, 2019
For Western consumers, giving up steak and lamb is arguably the single most important personal contribution to tackling both the climate and biodiversity crises.
(CNN)Humanity is on a collision course with nature. Already 72% of the global ice-free land surface is dedicated to supporting our species, and between a quarter and a third of the entire ‘net primary production’ of the planet is consumed by humans.
Net primary production is a measure of the combined photosynthetic output of all the world’s plants. Because we grab so much for ourselves, smaller and smaller amounts are left in the food chain for the rest of life on Earth.
No wonder so many other species are going extinct, displaced to the margins of existence in disappearing forests and degraded ecosystems. According to the latest International Union for Conservation Nature’s (IUCN) Red List, 40% of amphibians, 25% of mammals, 14% birds and 33% of corals are threatened with extinction.
And it’s only expected to get worse. Within another 30 years the global human population will exceed 9 billion people, meaning we will have to increase food production by at least another 70% in order to stave off mass famine.