What if we were stuck with the pests?

If all life on earth was rats and weeds...would it be so terrible?

Welcome to Team Trash, a newsletter about the places where humans and wildlife meet. I'm Bethany Brookshire, science journalist and author of the book Pests: How Humans Create Animal Villains.

"If we give up on diversity, then all of a sudden everything is going to be rats and sparrows and nothing else!" my source said with horror. "Do you want the only life on Earth to be based around a small handful of species and weeds?"

My source, a conservation biologist, was trying to make me see how awful it would be if we stopped fighting against invasive species. A world of pests and weeds.

My reply startled her. Because what I said was, "well, in a way, I think that's the world we're living in."

The scientist was arguing from the point of biodiversity. In conservation, biodiversity, for the sake of biodiversity, is always good. Places with more biodiversity are better than those with less. Everyone has seen an ecosystem on a documentary and heard David Attenborough intone "one of the most diverse places on the planet."

Conservation as a field is fascinating to me because it's one of the only scientific fields that comes with an implicit moral imperative: That some species, populations, and ecosystems are worth human intervention to save.

Think about it. Does physics come with a moral imperative? Aquatic biology? Chemistry? These fields fundamentally seek to understand. Sometimes, that does mean inventing or intervening. But that's not the goal of the enterprise, and the job of astronomy or botany isn't to change anything about the world we live in. It's to understand it.

Conservation, however, is about action. It's taking our understanding it and using it to preserve things we value. One of those things is biodiversity--the straight up diversity of species in an area. Species that are sometimes found nowhere else. And to preserve that diversity, conservationists will do a lot.

Say there's a population of a few hundred seabirds, unlike any anywhere else. Humans bring rats to the island. The rats begin to dine on seabird tartare. Biodiversity is at risk. Conservationists will drop thousands of tons of poison on that island, to kill the rats, and save that population of seabirds. When the rats come back? They will do it again.

I was asking that scientist whether we really should do that, whether that was the right decision to make. She said, from the view of biodiversity, the diversity of genes, it had to be. If we gave up the fight, if we let the seabirds go and the rats win, we were allowing the world of pests to take hold.

She saw it as a sad world. A world she wouldn't recognize. I agree, it would be very different. But I'm not sure it would be bad.

At the time, I told her it reminded me of the KT extinction, which I'd just been reading about in Riley Black's book The Last Days of the Dinosaurs. In her book, she talks about what life might have been like after the asteroid hit. The vast majority of species perished in moments, days and weeks after.

What survived? The few. The scuttling. The underground. The in the mud. The weeds.

The pests survived.

In a way, we are living in that world, the world of the pests. Biodiversity got hacked off, but life kept on. It produced redwoods and pandas and elephants and US. The wild biodiversity we see now isn't better or worse than the biodiversity we saw then. It is only different.

Pests have so much to teach us about resilience. I was reminded of this when I read Jacquelyn Gill's essay on looking to extinct species for resilience. They remind us that they lived, and they succeeded. They remind us, in a way, of our own power, that we know what it takes to survive.

Pests remind us of our weakness. They show us that when the asteroid comes? Someone's gonna make it. It may not be us. It may not be the seabirds.

It might be the rats. But even if it is the rats, the dandelions, and the sparrows, it won't be the end at all.

(Why is biodiversity good? Why do we consider biodiversity only as a diversity of species number and not diversity within a species? Those are tough questions for another time, though I highly recommend reading Emma Maris' book Wild Souls if you want to think about it very hard.)

Where have you been? 

I hope it's reading this great piece on the failures of COVID coverage by Kendra Pierre-Louis, specifically the idea that it's fine, we're all tired, and we should get back to normal. It's a failure of us, the media, one which we will carry for a long time.

Maybe it's reading this piece on mifepristone? Because you should. The fight you're hearing about in the news over this drug, one of the two used to induce medication abortions, is a political one. There is no scientific argument on the safety of mifepristone. It is safe.

Maybe it's reading about the new rat czar? She might have control over all the city's rodent managers. But until she has control of the sanitation? Bon chance.

Where have I been?

Writing about LEECHES! Oh yeah. Snail-borne diseases are a huge problem in many areas of the world, and to stop them, scientists want to stop snails. What stops snails? A hungry leech, it turns out. Maybe...

Thank you so much to everyone who came out to see my talks at NC State! I had a lovely visit and it was all because of you (and the adorable snake named Darwin who came to one of my talks. Shout out to Darwin).