Earth's wildlife populations have plunged by an average of 69% in just under 50 years, according to a leading scientific assessment, as humans continue to clear forests, consume beyond the limits of the planet and pollute on an industrial scale. From the open ocean to tropical rainforests, the abundance of birds, fish, amphibians and reptiles is in freefall, declining on average by more than two-thirds between 1970 and 2018, according to the WWF and Zoological Society of London's (ZSL) biennial Living Planet Report. Two years ago, the figure stood at 68%, four years ago, it was at 60%. Many scientists believe we are living through the sixth mass extinction " the largest loss of life on Earth since the time of the dinosaurs " and that it is being driven by humans. The Living Planet Index combines global analysis of 32,000 populations of 5,230 animal species to measure changes in the abundance of wildlife across continents and taxa, producing a graph akin to a stock index of life on Earth. Latin America and the Caribbean region " including the Amazon " has seen the steepest decline in average wildlife population size, with a 94% drop in 48 years. Land use change is still the most important driver of biodiversity loss across the planet, according to the report. Mike Barrett, executive director of science and conservation at WWF-UK, said: "At a global level, primarily the declines we are seeing are driven by the loss and fragmentation of habitat driven by the global agricultural system and its expansion into intact habitat."