You might very well walk out of her office and say to yourself: Whoa ... this is clearly the wake-up call I needed. I have to reconsider my choices and make these changes, as difficult as they may be. I owe it to myself and the people in my life who love and rely on me.

Then again, you might also say to yourself: Seriously? She expects me to do all that? I've been living this way my whole adult life. I can't stop now. I guess there's just nothing to be done.

Hundreds of millions of people around the world woke up last Monday morning to headlines that added up to a truly sobering prognosis for the world's ecosystems and the human beings who inhabit them. "Humans Are Speeding Extinction and Altering the Natural World at an 'Unprecedented' Pace," warned The New York Times. "Human society under urgent threat from loss of Earth's natural life" was how The Guardian opted to phrase it. The Washington Post didn't pull any punches, either, with its page-one, boldface augury: "One million species face extinction, U.N. report says. And humans will suffer as a result." Even more bluntly, New York magazine went with "Humanity Is About to Kill 1 Million Species in a Globe-Spanning Murder-Suicide."

The headlines all refer to a 40-page summary of the United Nations' Global Assessment Report on Biodiversity and Ecosystem Services, which, when published in its 1,500-page entirety later this year, will detail precisely how fragile life on this planet has become due to various choices made by one species: ours.

Nearly 150 scientists from 50 countries, aided by more than 300 additional experts, completed the assessment. They've run and re-run all the tests. And the results, as all those headlines indicate, aren't good.

To summarize the summary: Over our relatively brief existence, humans have significantly altered three-quarters of the planet's land-based environment and nearly two-thirds of its marine environment. More than a third of the world's land surface and nearly three-quarters of its freshwater resources are now dedicated to agricultural or livestock production. Our current habits and activities — very much including, but definitely not limited to, our burning of fossil fuels — have massively disrupted ecosystems and placed approximately a million plant and animal species at risk of extinction. It is the biggest biodiversity threat in all of human history.

When we look more closely at the ecosystemic X-ray, staggering details emerge. The average abundance of native species living in the planet's largest habitats on land has fallen by at least 20 percent, with most of that loss taking place since 1900. Over the past five centuries, at least 680 species of vertebrates have gone extinct, including more than 9 percent of all domesticated livestock breeds. Meanwhile, at sea, we are harvesting a third of all marine fish stocks at unsustainable levels.

In the words of Robert Watson, chair of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) that issued the report, "The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever. We are eroding the very foundations of our economies, livelihoods, food security, health, and quality of life worldwide."

To continue the medical diagnosis metaphor, the next few days represent the moment when humanity is walking out of the doctor's office in a daze. The next few weeks represent the elevator ride down to the ground floor, when we're replaying, in our heads, her words of warning. And the next few months represent our short ride home, during which we try to process what we've heard and almost reflexively veer toward one or the other of the aforementioned responses: Either we change, or we do nothing.

Hopefully we'll be telling ourselves: We can do this.

The alternative response — We can't — isn't really a response at all. It's the absence of one. Like a thoughtful physician, IPBES's Watson doesn't intend to give us the bad news and just stop there. The report also tells us that "it is not too late to make a difference, but only if we start now at every level from local to global," he said. Through what he labels transformative change — "a fundamental, systemwide reorganization across technological, economic, and social factors, including paradigms, goals, and values" — nature "can still be conserved, restored, and used sustainably."

For my part, I will continue to explore the various ways in which humans all over the world are working to restore our ecosystems: the ongoing efforts to save endangered species; to conserve the Canadian boreal, tropical rainforests, coral reefs, and other besieged habitats; to implement smarter land use practices; and to manage fisheries more sustainably. We need to integrate such solutions into a holistic regimen that will move us toward the "transformative change" we so desperately need for our own survival. You can't stave off a heart attack with a series of half measures; it's not enough to cut back from two packs of cigarettes a day to one, or to drop five pounds when you really need to drop 50.

But for now, in the immediate aftermath of our diagnosis, let's just agree that as bad as the situation is, we really do have what it takes to heal ourselves. Let's take a deep breath, clear our minds, open our eyes, and commit ourselves to meaningful change. There really is no other choice.

When Does Plant and Animal Species Loss Become a Societal Crisis? https://t.co/DkQNYb9J0b @DavidSuzukiFDN @GreenNewsDaily

— EcoWatch (@EcoWatch) April 19, 2019