Why Do We Keep Destroying the Homes of The World’s Creatures? Dinner

The earth is in the midst of the worst mass extinction since an asteroid wiped out the dinosaurs 66 million years ago — and this time, the asteroid is us. Human beings are displacing the planet’s other species at an unprecedented rate, a disaster that the landmark U.N. Biodiversity Conference known as COP15 is focused on this week in Montreal. We’re a unique menace, but we at least have a unique ability to recognize it and do something about it.

The first step toward recovery, of course, is admitting your problem, and the conference’s draft plan warns up front that a million species will face extinction if we don’t clean up our act. But while the delegates in Montreal are pointing fingers at everything from plastics to pesticides to invasive species, biodiversity loss is not that complicated a mystery.

The basic problem is that we’ve converted half the Earth’s habitable land into agricultural land. We’re destroying and degrading the habitats of other species to grow food for our own.

This means the fate of the world’s bugs, bunnies and other creatures and critters — and what’s left of the forests, wetlands and other habitats they call home — depends more than anything else on what we put in our mouths and how it gets made. Unfortunately, telling people what to eat and farmers how to farm are politically unpalatable tasks, which helps explain why yak-fests like COP15 tend to obscure the problem with word salad.

Environmentalists hope to leave Montreal with commitments from governments to preserve 30 percent of the Earth by 2030, and to meet 21 other targets. But governments have already failed to achieve less ambitious conservation goals set for 2010 and 2020. There’s also buzz around nailing down corporate commitments to greener supply chains, but COP15 is mostly dancing around the crux of the biodiversity crisis.

The crux is that if current eating and farming trends continue, the world will clear land equal to at least one and a quarter more Indias by 2050. That would be a disaster for the climate and wildlife, dooming carbon-rich and biodiverse ecosystems like the Amazon and Congo rainforests.

So those eating and farming trends better not continue. Humanity needs to start shrinking our agricultural footprint and expanding our natural footprint, after thousands of years of doing the reverse.

This will be an extraordinary challenge, because we’ll also need to produce more than 7.4 quadrillion additional calories every year to feed our growing population, in an era when climate-fueled droughts, heat waves, floods and blights could make it harder to grow food.

You can see why word salad can seem more appetizing.

You can also see why promises to conserve land or promote “deforestation-free” products can ring hollow. Governments can pledge to ban land clearing, but when their people get hungry, land will get cleared. Some companies might sign agreements to avoid soy or beef from newly deforested land, but it won’t do much if other companies keep buying soy or beef from newly deforested land.

If Homo sapiens are serious about cleaning up the mess we’re making for less influential species, there are four things individuals as well as nations and corporations can do.

The first is to eat less meat, which would be a lot easier if meat wasn’t so beloved and delicious. Limiting access to cheeseburgers can turn politicians into ex-politicians, so it’s no coincidence that the Montreal draft mentions changing diets only in passing in its 16th target. But the inconvenient truth is that when we eat cows, chickens and other livestock, we might as well be eating macaws, jaguars and other endangered species.

That’s because livestock chew up far more land per calorie than crops. Producing beef is 100 times as land-intensive as cultivating potatoes and 55 times as land-intensive as peas or nuts. Livestock now use nearly 80 percent of all agricultural land, while producing less than 20 percent of all calories. Cattle are the leading driver of deforestation in the Amazon, followed by soybeans, another commodity, which get fed to pigs and chickens.

Meat consumption is expected to increase dramatically as billions of the global poor escape poverty. If Americans continue to average three burgers a week while the developing world starts to follow our path, it’s hard to see how the Amazon survives.

But it’s at least possible that we could shrink agricultural footprints by shifting our diets toward meat made without livestock, like the plant-based substitutes offered by companies including Impossible Foods or Beyond Meat, or maybe someday “cultured meat” grown from animal cells.

The next thing we need to do is waste less food. About a third of the food grown on Earth is lost or tossed before it reaches our mouths, which means a third of the land (as well as the water, fertilizer and other resources) used to grow that food is also wasted. But the Montreal text includes only a single mention of the need to “halve per capita global food waste,” with no suggestions of what technological, behavioral and policy changes could help to meet such an ambitious goal.

Every acre of land on Earth matters, because we desperately need to grow more food, provide habitats for more native flora and fauna and store more carbon to limit climate change. And that’s why it’s particularly crazy to use the Earth’s limited land to grow fuel. The third way to ease the global land squeeze would be to stop using productive farmland for biofuels like ethanol and biodiesel — and to stop burning trees for power — but the Montreal plan doesn’t even address the topic.

In fact, there’s global momentum to expand bioenergy’s dominion over the land. A new paper in the journal Nature estimates that new European Union policies could wipe out half the continent’s most biodiverse grasslands and divert a fifth of its cropland to energy crops, which would lead to land clearing overseas to replace the lost food. The E.U. is also promoting wood-burning power plants, a recipe for massive forest cutting around the world.

Farm and forest interests have so much political power that government efforts to increase demand for crops and wood are often considered untouchable. But if biodiversity is a real priority, they can’t be.

Finally, if we’re going to shrink our agricultural footprint enough to stop deforestation, and hopefully restore some degraded ecosystems so they can once again serve as wildlife habitats and carbon sinks, farmers will have to supersize their yields enough to make a lot more food with a lot less land. And while the 20th century’s Green Revolution raised yields by using fossil-fueled fertilizers, toxic pesticides and other environmentally damaging innovations, the 21st century will require some greener ones that can ramp up productivity without messing up the planet.

Once again, this doesn’t seem like a priority in Montreal. There’s been much more focus on “regenerative agriculture,” “agro-forestry” and other gentler, lower-yield alternatives to intensive industrial farming that can improve biodiversity on farmland. The problem is that they can require more farmland to produce the same amount of food, accelerating the destruction of the natural lands that provide far more biodiversity than farmland ever can — and suck far more heat-trapping carbon from our overloaded atmosphere.

The Earth now has more than 12 billion acres of agricultural land, an area twice the size of North America. Adding more is the surest way to wipe out more species — and maybe, someday, our own.

Michael Grunwald, co-host of the Climavores podcast, is working on a book about how to feed the world without frying it.

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