There’s no human civilization without nature. It’s a simple, sobering calculation that’s gained urgent relevance in recent years as the global environment undergoes unprecedented changes, according to the latest report on the state of the planet from the World Wildlife Foundation (WWF).

But the true scale of that urgency is still being discovered. WWF’s “Living Planet Report” is the latest in a growing body of apocalyptic research that documents how wildlife around the world is rapidly declining, endangering humanity in the process.

The 59 scientists who worked on the report found that all wildlife populations have declined by an average of 60% since 1970, with freshwater fish species declining by 83% during this period, and animal populations in South and Central America plummeting by a staggering 89%.

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These declines are putting the delicate balance of the global environment at risk.

“We are sleepwalking towards the edge of a cliff,” Mike Barrett, executive director of science and conservation at WWF, told the Guardian. “If there was a 60% decline in the human population, that would be equivalent to emptying North America, South America, Africa, Europe, China and Oceania. That is the scale of what we have done.”

“This is far more than just being about losing the wonders of nature, desperately sad though that is,” he said. “This is actually now jeopardising the future of people. Nature is not a ‘nice to have’ – it is our life-support system.”

The report found that the root cause of this decline is human consumption, specifically the businesses, supply chains, and economies that provide what people consume.

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The overexploitation of species and land conversion cause the most direct harm, while climate change is gradually displacing species and undermining the ecosystems they depend upon.

More than half of all shallow water corals have been lost in the past 30 years, 20% of the Amazon rainforest has been razed over the past half century, and global wetlands have declined by 50% since 1990, according to the report.

The report goes on to describe the many ways in which nature supports humanity: The vast majority of medical advances have come from or been inspired by natural molecules, crops pollinated by animals provided 35% of our food, and natural ecosystems replenish, purify, and maintain our fresh water supplies.

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Nature also provides all the natural resources that support the global economy, worth an estimated $125 trillion. It cleans our air and soil, regulates the climate, and protects us from environmental disasters.

These are just a few of the macro-benefits of nature that are at risk of disappearing if drastic measures aren’t taken to protect the planet.

“The nature conservation agenda is not only about securing the future of tigers, pandas, whales and all the amazing diversity of life we love and cherish on Earth,” Marco Lambertini, WWF International Director General, said in the report. “It’s bigger than that. Our day-to-day life, health and livelihoods depend on a healthy planet. There cannot be a healthy, happy and prosperous future for people on a planet with a destabilized climate, depleted oceans and rivers, degraded land and empty forests, all stripped of biodiversity, the web of life that sustains us all.”    

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The WWF report joins a growing body of research that describes how species are declining and ecosystems are being destroyed.

Like the other studies, “Living Planet” goes into depth on various environmental threats, but the thrust of the report is about responding to this crisis to avert the worst consequences.

“This report sounds a warning shot across our bow. Natural systems essential to our survival – forests, oceans, and rivers – remain in decline. Wildlife around the world continue to dwindle,” Carter Roberts, president and CEO of WWF-US, said in a press release. “It reminds us we need to change course. It’s time to balance our consumption with the needs of nature, and to protect the only planet that is our home.”

The authors say that the global debate around the environment has to be reframed to emphasize the centrality of nature, global pacts that protect the environment have to be pursued immediately, and alternatives economies have to be developed.

“It’s clear that efforts to stem the loss of biodiv    ersity have not worked and business as usual will amount to, at best, a continued, managed decline,” the report concludes.

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“That’s why we, along with conservation and science colleagues around the world, are calling for the most ambitious international agreement yet – a new global deal for nature and people – to bend the curve of biodiversity loss. Decision-makers at every level from individuals to communities, countries and companies need to make the right political, financial and consumer choices to realize the vision that humanity and nature can thrive. This vision is possible with strong leadership from us all.”