Important as it is to focus on the climate challenge and its solutions, the University of British Columbia professor who co-created the concept of the ecological footprint is pointing to accelerating biodiversity loss as an equally urgent crisis.
“Biodiversity loss may turn out to be the sleeper issue of the century,” warns William Rees, UBC professor emeritus of human ecology and ecological economics. “It is caused by many individual but interacting factors—habitat loss, climate change, intensive pesticide use, and various forms of industrial pollution, for example, suppress both insect and bird populations. But the overall driver is what an ecologist might call the ‘competitive displacement’ of non-human life by the inexorable growth of the human enterprise.”
While humans 10,000 years ago only accounted for 1% of the total weight of mammals on the planet, that share now stands at 35% of a “much larger total biomass”—or an astonishing 98.5%, factoring in domestic pets and livestock. “One need look no further to explain why wildlife populations globally have plunged by nearly 60% in the past half-century,” he writes.
While it took 200,000 years for the human population to reach one billion in the early 1800s, the count stands at 7.6 billion just 200 years later. “Consumption has exploded accordingly—half the fossil fuels and many other resources ever used by humans have been consumed in just the past 40 years,” Rees notes.
Yet “H. sapiens depends utterly on a rich diversity of life forms to provide various life support functions essential to the existence and continued survival of human civilization,” he adds. “With an unprecedented human-induced great global die-off well under way, what are the chances the functional integrity of the ecosphere will survive the next doubling of material consumption that everyone expects before mid-century?”