This week in science: How albatrosses navigate, fossilized ocean worms, meteor shower
AILSA CHANG, HOST:
Time now for our science news roundup from our friends at NPR's Short Wave podcast, Aaron Scott and Regina Barber. Hello to both of you.
REGINA BARBER, BYLINE: Hey, Ailsa.
AARON SCOTT, BYLINE: Hey, Ailsa.
CHANG: So you have brought us three science stories that grabbed you this week. What have you got?
SCOTT: We've got peak viewing of a meteor shower.
BARBER: Plus a rare glimpse of what the ocean floor looked like 480 million years ago.
SCOTT: And how albatross use sound to help navigate the open ocean.
CHANG: Ooh. Let's start with that one, Aaron. Let's talk about the albatrosses.
SCOTT: Yes. Albatross are amazing. They're enormous. They have the largest wingspan of any bird on Earth, up to 11 feet. They can weigh as much as a toddler. And they're amazing long-distance flyers. They can cover thousands of miles in a single trip.
SCOTT: According to one calculation, over the course of their lifetime, they actually fly the equivalent of going to the moon and back 10 times.
CHANG: Oh, my god.
CHANG: Yeah. But like with all seabirds, all this travel raises a huge question. How do they navigate over the open ocean? There's no visible landmarks, so researchers think they must be using other cues. There's some evidence that they use smell and the Earth's magnetic field.
SCOTT: And now researchers have evidence for a new cue. In a paper in the Proceedings of the National Academy of Sciences, they found that wandering albatrosses tend to fly towards infrasound.
CHANG: Infrasound? Is that like infrared light but for sound? What is that?
SCOTT: Yes, exactly. It's just like infrared light is low-frequency light. Infrasound is low-frequency sound.
SCOTT: We humans can't hear it, but it's everywhere out there on the ocean because it's created whenever waves are colliding with each other. This is one of the paper's lead authors, Natasha Gillies. She's a postdoctoral researcher at the University of Liverpool.
NATASHA GILLIES: So the idea that other animals can perceive infrasound isn't totally novel. So elephants, some large cetaceans, like whales, are known to use it for communication. But the idea that it might be a cue for movement has been much less well explored, and certainly not at all in seabirds.
CHANG: Wow. I had no idea about elephants. OK, so how did the researchers explore this with albatrosses, albatrossi (ph)?
SCOTT: Albatrosses. They created acoustic maps of the ocean using data from a network of microphones that are set up to actually detect nuclear explosions. And then they attached GPS trackers to nearly 90 birds and compared where they flew through these acoustic maps.
BARBER: And they found that the birds were more likely to fly towards areas with louder infrasound created from strong colliding waves.
CHANG: OK. So it seems like the birds were actually trying to fly into areas with strong waves. Why would they do that instinctually?
BARBER: Well, they rely on wind to soar. And choppy, wavy areas generally mean a lot of wind and updrafts to give them a boost. Waves crashing against a shoreline also create infrasound, so they thought it also could have to do with them finding their way home.
SCOTT: Natasha says, to her knowledge, this is the first study to show that any animal is using infrasound to navigate. But she thinks it's just the beginning. And studying infrasound actually has implications for humans, too. Scientists are using it to improve weather predictions and climate models.
CHANG: OK. So that is from above the sea. But now we're going to go under the sea, right, Regina? You have a story about a really cool fossil from the ocean floor.
BARBER: Yeah. This fossil is from 480 million years ago. We're talking well before the dinosaurs. And the scene was detailed in a study that came out last week in Communications Biology. The fossil shows how animals lived with each other and sometimes on each other.
SCOTT: Yeah. In this case, a cephalopod with a shell, which is basically an ancient relative of the squid, it died and fell to the sea floor. And then these sea worms took up residence on its shell and built tough tubelike houses around themselves.
BARBER: Yeah. You can see 88 of them growing all over its dead body.
BARBER: Timothy Topper, a paleontologist not associated with the study, said it looked like a cephalopod having a bad hair day.
CHANG: A cephalopod that looks like Medusa. Wait. So, like, a bunch of worms living on a corpse? This is so gross, guys.
SCOTT: Yeah. Yeah. This is our Halloween theme. Although, you know, this happens at the bottom of the ocean every day. You might have heard about whale falls, Ailsa, where, like, a whale dies and sinks to the sea floor, and then its carcass becomes this giant all-you-can-eat buffet for crabs and other sea creatures that, you know, are living in this environment where there's just not much food. So you got to get it when you can find it.
CHANG: Wait. Wait. Wait. Back to the worms, though - what is so special about this particular fossil?
SCOTT: So scientists have found other fossils that just had fragments of the worms' homes on them. But Timothy says what's exciting here is that it's a whole colony. And you can see these two species - the worms and the dead cephalopod - interacting 480 million years ago.
BARBER: Yeah. That's one of the things that makes this fossil such a big deal to Karma Nanglu, the lead author of the study. He says the worms in this fossil are showing something called frozen behavior.
KARMA NANGLU: They're still found, like, on the dead shells of bivalves and things like that, growing their tubes - almost morphologically identical. It's a strategy that's kept them through every major mass extinction. They just kept on doing it. And, you know, half a billion years, no need to change.
CHANG: So disgusting, but so incredibly cool. All right. I want to end now on meteor showers. What do we got?
BARBER: Yeah. Yeah. So the Orionid meteor shower peaks this weekend. You can actually see the shower now or even days after this window. But this weekend is your prime sighting time.
SCOTT: And the meteors you're seeing are actually rocky dust burning up as it enters our atmosphere. And, Ailsa, you might need some coffee or hot cocoa because the peak magic happens in the wee hours between midnight and dawn.
BARBER: Yeah, super-late. And we're talking late Friday, October 20 and into the morning of Saturday, October 21.
CHANG: All night long, baby. Why would it be worth it for anyone to stay up all night for this? Like, what's so special about this particular meteor shower?
SCOTT: Well, Ailsa, all meteor showers are special. This one, though, has a couple of notable things. These meteors are pieces of a very well-known comet. I'll give you one guess as to which one it is.
SCOTT: You got it.
CHANG: It's, like, the only comment I know offhand.
SCOTT: Easy peasy. So as Halley's Comet travels in orbit, it leaves behind this whole path of dust and debris.
BARBER: Which becomes a meteor shower when it enters Earth's atmosphere. The Orionid meteors are especially known for their brightness and speed. We're talking 41 miles per second. So they leave glowing trails which can last for several seconds to minutes.
SCOTT: And one other fun fact - the Orionids get their name from the constellation Orion because it actually looks like that's where they're coming from. But, of course, they can be seen all across the night sky.
CHANG: OK. Maybe you sold me. I will stay up, maybe, all night for this. It's much easier for me to stay up all night than to get up really, really early in the morning anyway. So any other tips on how best to see this shower?
BARBER: Well, ideally, you want to try to find an area, like, away from city lights, streetlights, and always give your eyes time to adapt to the dark. We're talking something like 30 minutes or so.
SCOTT: And at its peak, under ideal conditions, the shower is expected to produce about 20 visible meteors an hour. So be patient. You aren't going to see one every few seconds.
CHANG: Just drink more wine.
CHANG: That is Regina Barber and Aaron Scott from NPR's science podcast Short Wave, where you can learn all about new discoveries, everyday mysteries and the science behind the headlines. Regina, Aaron, thank you so much.
SCOTT: Thank you.
BARBER: Thank you, Ailsa.
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