Perhaps you saw the memes, circulating like new variants of anxiety in the early months of the pandemic: a series of tidal waves, one following another and each taller than the last. The first wave represented Covid-19; behind it, and larger, the economic recession that would supposedly follow; then, a towering wave for climate change; and then, behind that and largest still, biodiversity collapse.
For the kind of person who has spent the past few years increasingly alarmed about climate, it might be strange to think of anything as looming larger than warming, which in recent decades has seemed to subsume not only all other ecological crises in the collective cultural imagination but also the existential fate of the species and the planet. The United Nations’ 15th international biodiversity conference just concluded in Montreal, and it received only a fraction of the press coverage lavished on the COP27 climate conference recently held in Sharm el Sheikh, Egypt. That imbalance may seem intuitive, given one of the core principles of climate action in the post-Paris-agreement era: that decarbonization should be the environmental goal above all others, and might even offer a silver bullet to solve (or at least alleviate) all sorts of other problems, from mass extinction and insect collapse to air pollution and global inequality.
For the cause of climate, this notion has been an undeniable boon, growing the movement by somewhat sidelining legacy concerns about conservation and forging alliances instead with forces that embrace technology, development and even “eco-modernism.” These years have also seen the rise of “degrowth,” and in recent intramural fights over permitting reform, climate centrists have argued that one major roadblock is sentimental old-guard activism, which amounts to a kind of climate NIMBYism. But in the long sweep of environmentalist history, the opposite story is more striking: “green” groups growing less attached to the natural world for its own sake and more invested in efforts to limit temperature rise for the sake of human flourishing.
One result has been genuine climate progress, and a rising hope that decarbonization, while still too slow, might unfold fast enough to at least avoid worst-case climate outcomes. But another is that the principles that gave rise to modern environmentalism 50 years ago are much less central to what goes by the name today: “Climate” has displaced “nature” as the primary locus of activist concern, pushing biodiversity somewhat farther from the policy center as well and affirming that the two causes are related but distinct. Among other things, this suggests the possibility that, however vital the work of cutting emissions, “addressing climate change will not ‘save the planet’” — as a headline of a recent piece in The Intercept, by Christopher Ketcham, put it.
That’s not because decarbonization requires catastrophic environmental harm. Though radically new infrastructure is necessary — new power lines, new building codes, new transportation systems — much of it would supplement or replace what exists today. While there are big questions about how to carry out the mining that will be necessary to produce a global green-energy boom, it would contribute only a modest increase to today’s mining sector and could even decrease overall mining.
The problem is that warming is just one of the many ways that human civilization is stripping the planet of its biological complexity. In fact, last December, in a commentary published in Conservation Letters, a group of biologists called climate change a “myopic lens” through which to view the biological decline of the planet and called warming far from “the most important horseman of the biodiversity apocalypse” — indeed more of a “mule,” powerful but slow. “The current perception that climate change is the principal threat to biodiversity is at best premature,” the authors wrote. “Although highly relevant, it detracts focus and effort from the primary threats: habitat destruction and overexploitation.”
Because we all live in the world as it is today, regarding both its dimly remembered past and its uncertain future from the relatively stable-seeming vantage of the present, it can be hard to understand the scope of even recent loss. But according to the World Wildlife Fund’s Living Planet Report, which looks at studies of some 32,000 species worldwide, vertebrate populations have declined on average by 69 percent since just 1970; since I was born in 1982, the decline has been more than 50 percent. In some ecosystems, the collapse of vertebrates has been even more drastic: In Latin America and the Caribbean, for instance, the studied populations have fallen on average by 94 percent since 1970, while among freshwater species that live in the world’s rivers and lakes, the estimated decline has been 83 percent.
As many as a million animal and plant species currently face the threat of extinction, according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (I.P.B.E.S.), a figure that translates to about 13 percent of bird species, 25 percent of mammals and 31 percent of sharks and rays. Insects are dying off, too — possibly more than 50 percent of them since 1970.
And while there are some success stories and local marks of ecological progress, today even the low estimates of global extinction rates suggest that overall, those rates are 100 times higher than would be expected without human activity; the less conservative estimates suggest extinction is happening thousands of times faster. Already 62 percent of global mammal biomass is livestock — animals raised by humans for our consumption. Four percent is wild. Taken together, humans and their food represent 96 percent of all mammal life on Earth.
One recent paper, published in Frontiers in Forests and Global Change, suggests that only 3 percent of global ecosystems remain intact. Other global tabulations are less bleak, but not by much. According to the I.P.B.E.S. — think of it as the biodiversity equivalent of the climate-change I.P.C.C. body — three-quarters of all land environments have been degraded by human activity and about two-thirds of all marine environments have. And while climate skeptics have spent a lot of energy arguing that warming is actually “greening” the world because CO₂ is plant food, a wide-ranging new study found the opposite: The planet as a whole, which was most likely greening just a few decades ago, is now probably browning instead.
Almost certainly, all this will get somewhat worse before it gets even somewhat better. The needs of the energy transition are significant, if not world-breaking, as are the growth demands of the world’s billion poorest. There are signs of progress on “decoupling” growth from both carbon and resource intensity, but the gains to this point have been only relative. And while there are signs of policy progress on conservation as well, including a growing awareness among the world’s leading policymakers of the importance of protecting the world’s ecological patrimony, the predominant mood in Montreal was lament: that a dozen years after some less-ambitious biodiversity targets were set for 2020, none of them have been met.
We’ve been here before, with climate, before the Paris agreement — an imperfect protocol, which has rallied the world’s governments to the task of decarbonization. Those accords didn’t just point toward a new policy consensus; they helped usher in a cultural transformation as well, because among the things that the new generation’s climate alarm has produced is a far more widespread understanding that warming risks devastation to humans and human society, not just animals and ecosystems.
There does not seem to be a similar shift coming for biodiversity, whose story remains largely the one we know already from “Silent Spring” to “The Lorax,” from “The Sixth Extinction” to “The End of Nature.” Even the most ambitious proposals — preserving 30 percent of the planet’s surface, protecting the Amazon from further deforestation — seem to point to a future defined as much by normalization as by conservation. We may well look around at that denuded world a generation from now and blithely conclude that “everything is fine.” But we’ll still probably marvel in wondrous disbelief that the planet was ever as full of life as it was in 2023.
