Reviving The Woolly Mammoth ... With Mice

Summary

Reviving The Woolly Mammoth ... With Mice
Short Wave, NPR
Release Date: March 4, 2025
Hosts: Emily Kwong and Regina Barber
Featuring: Rob Stein and Beth Shapiro

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Introduction: A Fuzzy Frontier in De-Extinction

In the March 4, 2025 episode of NPR's Short Wave, hosts Emily Kwong and Regina Barber explore an ambitious and controversial scientific endeavor: the revival of the woolly mammoth. This episode, titled "Reviving The Woolly Mammoth ... With Mice," delves into how scientists are leveraging genetic engineering and mouse models to potentially bring these extinct giants back to life.

The Woolly Mice: Bridging the Past and Present

Host Regina Barber opens the discussion with a lighthearted introduction, quickly transitioning to the core topic with co-host Rob Stein. At [00:37], Rob shares, “I'm here this time to talk about little fuzzy, squeaky animals… Woolly mice.” These genetically modified mice are not your ordinary lab specimens; they showcase traits reminiscent of the extinct woolly mammoths, serving as crucial steps toward de-extinction.

Colossal Biosciences' Bold Mission

Rob Stein provides context about Colossal Biosciences, a Dallas-based biotech company spearheading this project. The company's goal is to reincarnate mammoth-like elephants by infusing modern Asian elephants with key mammoth traits such as thick coats and specialized fat metabolism necessary for Arctic survival ([03:20] Rob Stein).

Beth Shapiro, Colossal’s Chief Science Officer, explains the foundational work: “We ask, where are all of the mammoths? The same as each other, but different from an elephant. So this is narrowing down the focus on the genes that make mammoths mammoths instead of elephants” ([04:04] Beth Shapiro). By comparing ancient DNA from mammoth remains with that of living elephants, scientists have pinpointed approximately ten candidate genes responsible for the mammoths' distinctive features.

The Role of Mice in Genetic Research

Given the lengthy gestation periods of elephants ([04:39] Beth Shapiro), using Asian elephants to test these genetic modifications would be impractical and unethical, especially considering their endangered status. Instead, researchers turn to mice, which reproduce rapidly and allow for swift experimentation. Beth comments, “With a mouse model, we can really rapidly test these hypotheses and learn whether this change might be responsible for making the animal woolly” ([05:00] Beth Shapiro).

Successes in Creating Woolly Traits

The manipulation of mouse genetics has yielded promising results. As Rob Stein narrates, “One change gave the mice hair three times longer than usual. Another made their coats wavy. Another turned their coats this kind of golden blonde color, like mammoths” ([06:07] Rob Stein). These alterations have produced adorable, woolly mice that visually mirror the iconic appearance of woolly mammoths, providing valuable proof-of-concept for the de-extinction project.

Scientific Community’s Mixed Reactions

While the project has garnered excitement, it has also sparked debate within the scientific community. Vincent Lynch, a biology professor at the University of Buffalo, expresses skepticism: “A mouse is not an elephant” ([08:01] Rob Stein). He acknowledges the technical achievements but cautions against assuming that the same genetic modifications will translate effectively to larger, more complex organisms like elephants.

Moreover, concerns about ecological impacts and ethical considerations have been raised. Carl Flesa, a geosciences professor at the University of Arizona, questions the unforeseen consequences of introducing genetically engineered elephants into tundra ecosystems: “They sort of want to mess around on a pretty large scale… I don’t know what would happen” ([08:34] Rob Stein).

Defending the Vision: Environmental Restoration and Conservation

In response to critiques, Beth Shapiro defends the project’s environmental intentions: “Our intention is to recreate these extinct species that played really important roles in ecosystems that are missing because they've become extinct” ([09:18] Rob Stein). Colossal Biosciences founder Ben Land emphasizes the broader conservation implications, suggesting that the technologies developed could aid in preventing further extinctions by providing new tools and methods for conservation: “Current conservation models work. They just don’t work at the speed” ([09:51] Rob Stein).

Future Prospects: From Mice to Mammoths

Looking ahead, Colossal Biosciences aims to produce mammoth-like Asian elephant embryos by next year, with hopes of birthing the first genetically modified calves by 2028 ([10:01] Rob Stein). This timeline underscores the project's ambitious nature and the rapid advancements in genetic engineering techniques.

Conclusion: A Science Fiction Becoming Reality

The episode wraps up with Regina Barber reflecting on the profound implications of this research. The endeavor to revive the woolly mammoth using mice as genetic models represents a fascinating intersection of genetics, conservation, and ethical considerations. As Colossal Biosciences progresses, the scientific community and the public alike will be closely watching to balance the promises of restoration with the responsibilities of ecological stewardship.

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Notable Quotes:

• Rob Stein [00:37]: “I'm here this time to talk about little fuzzy, squeaky animals… Woolly mice.”
• Beth Shapiro [04:04]: “We ask, where are all of the mammoths? The same as each other, but different from an elephant…”
• Beth Shapiro [05:00]: “With a mouse model, we can really rapidly test these hypotheses…”
• Rob Stein [06:07]: “One change gave the mice hair three times longer than usual…”
• Vincent Lynch: “A mouse is not an elephant.”
• Beth Shapiro [09:18]: “Our intention is to recreate these extinct species that played really important roles in ecosystems…”
• Ben Land: “Current conservation models work. They just don’t work at the speed…”

This comprehensive summary encapsulates the episode's exploration of de-extinction efforts, highlighting both the scientific breakthroughs and the ethical debates surrounding the revival of the woolly mammoth through innovative genetic research.

Transcript

[Rob Stein]

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[Regina Barber]

You're listening to Short Wave from npr. Hey there, short wavers. Regina Barber here, and today I'm joined by NPR's Rob Stein. Hey, Rob.

[Rob Stein]

Hey, Gina.

[Regina Barber]

Rob, you're usually here to talk about stuff related to health, like Covid or CRISPR or organ transplants, but word on the street is today is a little different.

[Rob Stein]

Yep, I'm here this time to talk about little fuzzy, squeaky animals.

[Regina Barber]

Okay, let me guess. Do they like cheese?

[Rob Stein]

How did you know? Yes, indeed. I'm talking about mice. And these aren't just any mice, okay? These are. Wait for it. Woolly mice.

[Regina Barber]

Okay, woolly mice. Rob, what makes them woolly?

[Rob Stein]

Well, Tina, you've heard of the woolly mammoth, right?

[Regina Barber]

Of course. I love those hairy elephants. They used to roam the tundra. They were actually still around when the pyramids were built.

[Rob Stein]

Exactly. Before they went extinct thousands of years ago. Maybe because of climate change and hunting.

[Regina Barber]

Okay, so these mice, they're like miniature versions of woolly mammoths.

[Rob Stein]

Bingo. Cool.

[Regina Barber]

Okay, but why are you bringing them up now?

[Rob Stein]

Well, because someday some scientists want to bring a mammoth like creature itself back from extinction.

[Regina Barber]

Wow. So they have, like, Jurassic park like intentions.

[Rob Stein]

Yes, exactly. These scientists, they work at a Dallas biotech company called Colossal Biosciences, and they say these little woolly mice are a key step towards that. Audacious and I have to say, quite controversial. Cold.

[Regina Barber]

Wow. Okay, so today on the show, woolly mice and what they mean for the elusive goal known as de extinction. You're listening to Shortwave, the science podcast from npr.

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[Regina Barber]

Okay, Rob, we're going to go from mice to mammoths. Let's start with these woolly mice. Like, how are they different from normal M, and how were they created? Exactly.

[Rob Stein]

So to answer that, I have to start with the mammoths.

[Regina Barber]

Okay.

[Rob Stein]

Colossal Biosciences wants to bring the mammoth back by using the latest genetic engineering techniques to create modern day elephants with key traits from the mammoth. Cool. You know, traits like their signature thick coat and their fat metabolism that kept them warm in the Arctic.

[Regina Barber]

And how do they go about doing that?

[Rob Stein]

So they started by comparing genomes from samples of ancient DNA recovered from mammoth remains with genomes from living African and Asian elephants, the mammoth's closest living relatives.

[Beth Shapiro]

We ask, where are all of the mammoths? The same as each other, but different from an elephant. So this is narrowing down the focus on the genes that make mammoths mammoths instead of elephants.

[Rob Stein]

That's Beth Shapiro, the chief science officer at Colossal.

[Regina Barber]

So in practice, I imagine they're like, hunting for genes responsible for iconic, you know, mammoth traits, like their distinctive coat and their maybe their fat.

[Rob Stein]

Exactly. And they narrowed down that list of candidate genes to 10 genes for the coat and the fat.

[Regina Barber]

Okay.

[Rob Stein]

But they wanted to make sure that the genes they had identified were really responsible for the traits that they wanted. They couldn't just, you know, try to engineer Asian elephants with genes they thought might control those traits, because it would be unethical, given the fact that Asian elephants are endangered.

[Beth Shapiro]

Here's a difference. In a letter, in a long string of as and Cs and GS and Ts, a genome of a mammoth that we've gotten out of a bone that was preserved in the permafrost in Siberia. It's hard to test that in an elephant because an elephant is pregnant for 22 months, and then it takes another decade to 14 years for that elephant to be able to have a baby.

[Rob Stein]

Mm.

[Regina Barber]

So it takes a lot of time to isolate those genes, insert them into, like, Asian elephant embryos, wait to see if that, like, pans out, then, like, go back to the drawing board with the next one.

[Rob Stein]

But a mouse is a different, different story.

[Beth Shapiro]

With a mouse model, we can really rapidly test these hypotheses and learn whether this change might be responsible for making the animal woolly. And now I can add that to the list of things that I want to change. When I'm editing that Elephant cell so that I can have an elephant someday give birth to something that looks more like a mammoth.

[Regina Barber]

Wow. Okay, so that's where the mice come in. Like, they reproduce so quickly. There's so many generations, and they get more data faster.

[Rob Stein]

Yeah, yeah, exactly. That's exactly how it works. The mice are great little critters for doing these kinds of experiments, seeing the effects of genetic changes because they reproduce so fast. And scientists, you know, they just know how to work with them.

[Beth Shapiro]

We look in the mouse for those same genes and instances where those genes have been involved with making a woolly coat or longer hair or changing the color of the hair.

[Regina Barber]

And so they can see. Like, did this gene that shows up in the woolly mammoth DNA have like, the same effect in mice or giving.

[Rob Stein]

The animals fat that protects them from the Arctic cold? Okay, did that. The researchers used different kinds of genetic manipulation to modify the genes in mouse eggs and mouse embryos and then used those to breed mice they hoped would have those traits. And you know what, Gina? It appears to have worked.

[Regina Barber]

Wow, that's so awesome.

[Rob Stein]

Yeah. One change gave the mice hair three times longer than usual. Another made their coats wavy. Another turned their coats this kind of golden blonde color, like mammoths, et cetera, et cetera.

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Wait, wait.

[Regina Barber]

So not dark brown, like children's book. When I see the mammoths, are those mammoths just, like, dirty?

[Rob Stein]

That's the idea. I mean, these little creatures, you know, they kind of look like what mammoths would look like if they had a good bath and a blowout.

[Beth Shapiro]

We ended up with some absolutely adorable mice that have longer, woolly, golden colored coats.

[Rob Stein]

Gina, I'll send you some photos of them right now.

[Regina Barber]

Okay. Okay, I'm gonna look. Oh, my gosh. They look like little craft, like, things that you could actually make, like little dolls.

[Rob Stein]

I know. Don't you just want to cuddle up with them? They're so fuzzy looking.

[Regina Barber]

Totally. I mean, they must be so excited about this.

[Rob Stein]

Yeah. And that's exactly what Beth told me when I talked to her about this.

[Beth Shapiro]

For us, it's an incredibly big deal. I mean, this is really validation that what we have in mind for our longer term de extinction projects is really going to work.

[Rob Stein]

And that will enable them to create mammoth, like, Asian elephants by genetically engineering Asian elephant embryos with the traits that made the mammoths mammoths and planting those edited embryos into female Asian elephants, you know, surrogates, to hopefully breed these mammoth like creatures with the ultimate goal of releasing herds of these creatures back into the Arctic someday, which, on One hand.

[Regina Barber]

Like, is a huge deal. Right. But, like, on the other hand, is pretty controversial. So do you have a sense of, like, what other scientists think about all this?

[Rob Stein]

Well, you know, some other scientists think it's pretty cool, at least on one level. Like, you know, Vincent Lynch. He's a professor of biology at the University of Buffalo. You know, I'm pretty skeptical about this, but that mouse is pretty adorable. And for people like me who want to understand the genetic basis of traits, this is particularly impressive. But Vincent and others caution, a mouse is not an elephant. So who knows if they could do the same thing with that species.

[Regina Barber]

Right, Right.

[Rob Stein]

And even if they could, Vincent is among those who don't think bringing back the mammoth is such a great idea.

[Regina Barber]

Oh, okay. Why is that?

[Rob Stein]

Well, they think, first of all, that the money would be much better spent saving species that are still alive but are on the brink of extinction. And also, who knows what unintended consequences could result. I talked about this with Carl Flesa. He's a professor of geosciences at the University of Arizona. They sort of want to mess around on a pretty large scale. I don't know what the downside of having a bunch of hairy Asian elephants stomping around in the tundra might be. I don't know what would happen. They don't know what would happen. They can't really assure me that, oh, everything will be just fine. Everything will be just like it was back in the Pleistocene. I'm not ready to play God like that.

[Regina Barber]

Wow, I hadn't thought of that. So what do some folks at La Colossal say about all these concerns?

[Rob Stein]

Well, Beth and her colleagues, they defend their project. They say reintroducing mammoth like creatures could actually repair the environment by, you know, helping restore the ecosystems where the mammoth once lived.

[Beth Shapiro]

Our intention is to recreate these extinct species that played really important roles in ecosystems that are missing because they've become extinct. And that is our goal with our de extinction projects.

[Rob Stein]

And Ben Land, Colossal's founder and CEO, says the tools the company's creating in this project could help prevent more species from going extinct.

[Beth Shapiro]

Current conservation models work.

[Rob Stein]

They just don't work at the speed.

[Beth Shapiro]

At which we are changing the planet and eradicating species. So we need new tools and technologies so that we can engineer life in.

[Rob Stein]

A better way that's more adaptable, to be coexistent with humans. The researchers say they hope to produce their first mammoth like Asian elephant embryos next year.

[Regina Barber]

What?

[Rob Stein]

Yeah. That's so soon. Then they'll implant them into female Asian elephants, which will hopefully give birth to the first mammoth like Asian elephant calves by 2028. Wow.

[Regina Barber]

I'm Mark Calendar. Sorry. I'll let you keep going.

[Rob Stein]

And you know, Gina, they're also working on bringing back other extinct creatures like the dodo bird and the Tasmanian tiger.

[Regina Barber]

Wow. Okay. Well, Rob, you've given me a lot to think about. Thank you so much for bringing this story to Shortwave.

[Rob Stein]

Oh, anytime, Gina. It's been fun.

[Regina Barber]

For all. You listening. If you liked this episode, make sure you never miss a new one by following us on whatever podcasting platform you're listening from. And if you have a science question you'd like us to investigate, send us an [e-mail] this episode was produced and edited by our showrunner, Rebecca Ramirez. Tyler Jones checked the fact Robert Rodriguez was the audio engineer, Beth Donovan is our senior director, and Colin Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thank you for listening to Short Wave from npr.

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