How did these flowers evolve to survive a megadrought?

Summary

Short Wave — "How did these flowers evolve to survive a megadrought?"

Podcast: Short Wave (NPR)
Episode Date: March 20, 2026
Hosts: Emily Kwong, Nate Rott, Elsa Chang (guest host)
Length: ~10 minutes of content

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Episode Overview

This episode of Short Wave features a lively science news roundup discussing three recent and intriguing discoveries: how wildflowers evolved to survive a megadrought, the mechanics of birds' dust bathing, and the surprising social lives of bull sharks. Hosts Emily Kwong and Nate Rott are joined by Elsa Chang from All Things Considered for a fast-paced, informative, and occasionally humorous look at the stories behind the headlines.

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1. Scarlet Monkey Flower: Evolution Amid Drought

Segment Start: [02:34]

• Introduction:
  Elsa chooses to start with the story of the scarlet monkey flower, a wildflower native to California and Oregon, notable for its vibrant red, monkey-face-like petals.
• Biologist Daniel Anstedt (Cornell University):
  Describes the plant as “bright red … with all this kind of pollen up front that's really set up for a hummingbird to just kind of fly in and drink some nectar.” ([02:47])
• The Mystery:
  While scarlet monkey flowers typically die quickly without water, some wild populations survived an intense megadrought. This phenomenon was the subject of a new paper in Science.
• Secret to Survival: Rapid Evolution
  • Some populations underwent "rapid evolution," meaning genetic changes took place over just a few years, enabling survival during extreme drought.
  • The key trait: stomata (plant “pores”) that open less frequently, conserving water—an adaptation that allowed these plants to endure. ([03:34])
  • Quote: Emily explains, “That’s basically like a plant’s pores. And this allowed the scarlet monkey flowers to hunker down in the drought. Slow and steady survives.” ([03:45])
• Long-Term Impact:
  • The team, led by Daniel Anstedt, tracked the same flower populations for over a decade; they are collecting seeds for genetic sequencing, aiming to build a generational study akin to Darwin’s finches. ([04:08])
  • Daniel Anstedt: "That's what we hope to build with this study. Is this long term study because, yes, rapid evolution happened great. ... But what are the longer decadal consequences?" ([04:16])
• Open Questions:
  • Will these rapidly adapted flowers maintain enough genetic diversity to respond to future environmental changes, like insect infestations or future deluges?

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2. Dust Bathing Birds: Nature’s ‘Sandblasting’

Segment Start: [04:42]

• Introduction:
  Elsa is fascinated by the idea of “dust bathing” in birds—a behavior she likens to a spa treatment.
• What is Dust Bathing?
  • Described as chickens (and other birds like ostriches, turkeys, and some songbirds) digging into dirt or sand, wriggling their wings and tossing sand over themselves.
  • Emily jokingly claims, “I did it this morning. I highly recommend.” ([05:04])
• Why Birds Dust Bathe:
  • Maintains healthy feather oil balance—like “dry shampoo” for birds ([05:33])
  • Removes parasites, including feather mites which “can burrow into a bird plumage and cause itching, scabbing, anemia, and all sorts of other bad things.” ([05:47])
• The Study:
  • Conducted by Patricia Yang (National Tsinghua University, Taiwan) and published in PNAS.
  • Experiment: Collected mite-covered chicken feathers, vibrated them in sand at 4–5 times per second (mirroring birds’ wing shakes). Result: Nearly all mites were removed. ([06:17])
• Takeaway:
  • Nate summarizes, “Basically what the birds are doing is sandblasting themselves.” ([06:40])
  • Guest engineer Andrew Dickerson (University of Tennessee) notes this supports the idea that animals evolved optimized ways to remove contaminants, and engineers might one day mimic these techniques.
• Fun Aside:
  Elsa jokes about trying sand baths for humans with lice: “I have some sand the next time I get infested, guys.” ([06:35])

---

3. Bull Sharks Have Friends: Social Lives Underwater

Segment Start: [07:14]

• Introduction:
  Nate, an avid surfer, brings up a study about the social behaviors of bull sharks.
• Bull Sharks:
  • Large, globally distributed sharks typically found in warm, shallow waters.
  • Emily: “They’re really social, and they like hanging out with each other.” ([07:27])
• Study Details:
  • Shark scientist Natasha Morosi and her team studied 184 bull sharks over six years at Fiji’s Shark Reef Marine Reserve.
  • Identification via tags, video, and even individual scars or swimming patterns: “Natasha can actually tell who’s who just by like looking at their wounds or scars and sometimes just by the way they swim.” ([08:08])
• Findings:
  • Sharks were observed forming consistent social groups—such as the “boys club” trio: Chunky, Mogul, and Shark Bite.
  • Encounters were not random; sharks demonstrated preference, swimming parallel or altering direction to be with specific others ([08:41]).
  • Middle-aged sharks appeared at the center of these networks, while young and old were less connected.
• Caveats:
  • Guest researcher Catherine McDonald urges caution: while behaviors are social, they shouldn’t be equated too closely with human friendship.
• Humorous Moment:
  • Nate highlights the paper’s title: “Rolling in the Deep. Dun dun dun dun dun.” ([09:21])

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Notable Quotes & Memorable Moments

• Emily Kwong (re: monkey flowers):
  “That’s basically like a plant’s pores. And this allowed the scarlet monkey flowers to hunker down in the drought. Slow and steady survives slow and steady.” ([03:45])
• Daniel Anstedt (Cornell biologist):
  “...But what are the longer decadal consequences?” ([04:16])
• Elsa Chang (on dust bathing):
  “Sand does not sound comfortable to me at all.” ([05:29])
  “I have some sand the next time I get infested, guys.” ([06:35])
• Nate Rott (on dust bathing):
  “Basically what the birds are doing is sandblasting themselves.” ([06:40])
• Emily Kwong (on sharks):
  “They’re really social, and they like hanging out with each other.” ([07:27])
• Elsa Chang (on shark pals):
  “Chunky, Mogul and Shark Bite, the Voice Club. I love it.” ([08:26])
• Nate Rott (on paper title):
  “Rolling in the Deep. Dun dun dun dun dun.” ([09:21])

---

Key Timestamps

• [02:34] — Begin wildflower evolution segment
• [03:34] — Explanation of stomata adaptation
• [04:16] — Ambitions for long-term evolutionary studies
• [04:42] — Begin segment on dust-bathing birds
• [06:17] — Sand-vibration experiment details
• [06:40] — "Sandblasting" analogy
• [07:14] — Begin bull shark segment
• [08:41] — Methods for identifying shark friendships
• [09:21] — Shark study paper's humorous title

---

Summary & Takeaways

This episode brings together three fascinating snippets from the natural world:

• Rapid evolution allows certain plants to survive unforgiving droughts, shedding light on both the variability and adaptability of life.
• Birds’ unusual “dust baths” aren’t just quirky behavior—they’re a refined evolutionary response to parasites, with potential inspiration for engineers.
• Sharks, often stereotyped as lone predators, can form lasting group bonds and intricate social networks.

In just ten minutes, the episode serves up vibrant conversation, humor, and illuminating science, making it engaging listening for science fans and the curious alike.

Transcript

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[Emily Kwong]

You're listening to shortwave from npr. Hey, shortwavers.

[Nate Rott]

Emily Kwong here and Nate Rott. Hello.

[Emily Kwong]

Hello. And today we have our bi weekly science news roundup featuring the host of All Things Considered. And here with us is the glorious Elsa Chang.

[Elsa Chang]

Hi. Hi.

[Nate Rott]

Hi.

[Elsa Chang]

Okay, I hear we're going to be talking about the social lives of sharks.

[Emily Kwong]

Yes. And we have another story about a rapidly evolving wildflower and another that looks

[Nate Rott]

at a, let's call it, counterintuitive grooming behavior in birds.

[Emily Kwong]

All that on this episode of Short Wave, the science podcast from npr.

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[Emily Kwong]

which story do you want to start with?

[Elsa Chang]

Ooh, Well, I want to start with the wildflowers.

[Emily Kwong]

Lovely.

[Nate Rott]

Good choice.

[Emily Kwong]

Yes. Allow me to introduce you to the scarlet monkey flower. That is a plant with vibrant red petals whose flowers kind of look like a grinning monkey.

[Elsa Chang]

That's Amazing.

[Daniel Anstedt]

It is a plant that's bright red that has all this kind of pollen up front that's really set up for a hummingbird to just kind of fly in and drink some nectar.

[Emily Kwong]

Plant biologist Daniel Anstedt at Cornell University said that without water, these flowers will die in a few days. However, several wild populations in California and Oregon survived this intense megadrought. Wow. Yeah. This wildflower mystery is the focus of a new paper in the journal Science.

[Elsa Chang]

Wait, so what are the monkey flowers secrets to survival?

[Nate Rott]

Well, Elsa, it turns out some wild populations are able to survive this exceptional drought through something called rapid evolution. It's when populations go through genetic changes in a very short time period.

[Elsa Chang]

So cool. Okay, so which traits did these surviving flowers have?

[Emily Kwong]

Yeah, the scientists found that 3 of the populations that recovered the best adapted their stomata to open less stomata. Yeah. So they could conserve more water. Stomata. Yeah, that's basically like a plant's pores. And this allowed the scarlet monkey flowers to hunker down in the drought. Slow and steady survives slow and steady.

[Elsa Chang]

How did the scientists even figure this out?

[Nate Rott]

Well, so they looked at the same populations of scarlet monkey flowers for over a decade. They hiked out to these, like, remote populations of monkey flowers, checking which plants lived, which died, and they collected their seeds for genetic sequencing.

[Emily Kwong]

And Daniel hopes this work will continue for decades. Just like the long term studies on Charles Darwin's famous finches in the Galapagos.

[Daniel Anstedt]

That's what we hope to build with this study. Is this long term study because, yes, rapid evolution happened great. Those populations did good in one time point. But what are the longer decadal consequences?

[Nate Rott]

Like, so what if an insect comes along or there's a prolonged period of rain? Will the survivors have enough genetic variation within them to respond? Again, that's kind of the roll of the dice at evolution brings. And this is the kind of science that shows how it all goes down.

[Elsa Chang]

Fascinating, but I am still processing how a flower can look like a grinning monkey. Anyway, next topic, bathing birds. Tell me more.

[Nate Rott]

Yeah, so, Elsa, it's not the kind of bathing that you might be thinking of. This study looks at the mechanics of something called dust bathing, which I'm embarrassed to admit I didn't even know was, like a thing.

[Elsa Chang]

Me neither. Sounds like a great spa treatment.

[Emily Kwong]

Go ahead. I did it this morning. I highly recommend no dust bathing. Ostriches do it. Some species of songbirds, turkeys, and chickens. Patricia Yang, an assistant professor at National Tsinghua University in Taiwan, says a bath for a chicken Involves dirt and sand.

[Elsa Chang]

Ouch.

[Emily Kwong]

And the chickens start, like, digging themselves into the mud and start, like, wiggling their wings and then put the sand on them.

[Elsa Chang]

Sand does not sound comfortable to me at all.

[Nate Rott]

Right. It sounds a bit counterproductive, but scientists have actually known for a while that it's a pretty useful behavior because it helps birds maintain the right amount of oil on their feathers. Kind of like a dry shampoo. Right? You might do that, Elsa. And it helps them get rid of

[Emily Kwong]

parasites, tiny little bugs like feather mites, which can burrow into a bird plumage and cause itching, scabbing, anemia, and all sorts of other bad things.

[Elsa Chang]

Wait, but how does taking a dirt or sand bath help a bird get rid of all those gross parasites and bugs?

[Nate Rott]

So, yeah, so that's what Yang really wanted to find out with this new study, which published in the Proceedings of the National Academy of Sciences. And to do that, she ran an experiment where she collected sand and then a bunch of mite covered chicken feathers from a farm on Taiwan.

[Emily Kwong]

And then they vibrated those feathers in the sand at a rate of four to five times per second, the same frequency chickens usually reach shaking their wings during dust baths. And almost all of the mites fell off.

[Elsa Chang]

I wonder if this would work with humans who have lice.

[Nate Rott]

I mean, welcome to try it out in a sandbox.

[Elsa Chang]

I have some sand the next time I get infested, guys.

[Nate Rott]

I mean. Yeah. So to put it another way, what happened here?

[Babbel/Wix Ad Voice]

I mean, basically what the birds are doing is sandblasting themselves.

[Nate Rott]

That's Andrew Dickerson, a mechanical and aerospace engineer at the University of Tennessee, Knoxville. And he was not involved in this new study, but he has researched the frequency at which do shake their body to rid themselves of water. And he says the new paper backs up one of the things that he's found, that animals have some pretty finely tuned ways of getting rid of contaminants like mites or water, be it shaking off or agitating sand. And maybe there's something that engineers and technologists can learn from those behaviors.

[Elsa Chang]

Wow. Okay, now for our final topic. Sharks.

[Nate Rott]

That is correct. And as a surfer, this paper totally caught my eye, because bull sharks have friends.

[Elsa Chang]

Oh, wait, what's a bull shar again?

[Emily Kwong]

Bull sharks. They are found worldwide in warm, shallow waters, and they're really big. Like, females can grow about 3 meters or 11ft. And what's cool about this paper is they. Yeah, they're really social, and they like hanging out with each other.

[Elsa Chang]

Wait, they're, like, friendly. They're like gregarious sharks.

[Emily Kwong]

Well, what the paper is saying is basically individual sharks seem to have a distinct preference for some sharks over others. Yeah. Natasha Morosi is a shark scientist and she and her team looked at 184 Bull Sharks over six years in the Shark Reef Marine Reserve in Fiji. They observe sharks by tagging them and through video recordings of dives.

[Nate Rott]

And get this all said, Natasha can actually tell who's who just by like looking at their wounds or scars and

[Elsa Chang]

sometimes just by the way they swim.

[Nate Rott]

And as far as the shark social lives, the researchers saw some sharks consistently hang out with each other over the course of the study. Like these perfectly named three pals, Chunky

[Elsa Chang]

and Mogul and Shark Bite were like the boys club. Chunky, Mokul and Shark Bite, the Voice Club. I love it. Wait, wait, but these sharks are just like swimming near each other, right? Like, how do we know that is evidence of the sharks actually being social?

[Nate Rott]

Yeah. So in this study, Natasha says they looked at specific behaviors to see if sharks are making active choices about who to hang out with. So that meant if they swam parallel to one another or if they change direction to join or follow another shark.

[Emily Kwong]

Yeah. And the team found that a shark's age made a difference in who they associated with. Middle aged bull sharks tended to be at the center of social networks with more connections than younger or older sharks.

[Elsa Chang]

Interesting.

[Nate Rott]

Yeah. And a shark researcher who didn't work on this paper, Catherine McDonald, also cautioned against too many comparisons to human friendship since we don't really know what these interactions mean. The results are in the journal Animal Behavior. And Elsa, just a reminder that scientists do have a sense of humor. The title of this paper is Rolling in the Deep. Dun dun dun dun dun.

[Elsa Chang]

Nice, Elsa.

[Emily Kwong]

So fun to have you on.

[Elsa Chang]

So fun. I love hanging out with you guys.

[Nate Rott]

Yeah, come back anytime.

[Elsa Chang]

Thank you to both of you.

[Emily Kwong]

You can hear more of Elsa on consider this NPR's afternoon podcast about what the news means for you.

[Nate Rott]

And for more science stories just like this one, follow Short Wave on whatever app you're listening to.

[Emily Kwong]

This episode was produced by Jeffrey Pierre, Rachel Carlson and Hannah Chinny. It was edited by Christopher Inteliota and Rebecca Ramirez. Arun Iyer checked the facts.

[Nate Rott]

Becky Brown and Robert Rodriguez were the audio engineers.

[Emily Kwong]

I'm Emily Kwong.

[Nate Rott]

And I'm Nate Rott.

[Emily Kwong]

Thanks for listening to Short Wave. Later. Later, gators.

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