How These Spiders At The Bottom Of The Sea Run On Methane

With the help of methane-munching-microbes, these translucent sea spiders gobble up a potent greenhouse gas to stay alive.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

  WNYC is supported by Bayer. Science is about asking questions, testing, trying again. It's not easy, but it's relentless. It evolves, and that's why science delivers. Learn more at sciencedelivers.com.

• 0:14Ira Flatow?

  Science Friday is supported by MathWorks, creator of MATLAB and Simulink software for technical computing and model-based design. MathWorks, accelerating the pace of discovery in engineering and science. Learn more at mathworks.com.

• 0:31Flora Lichtman?

  Hey, I'm Flora Lichtman, and you're listening to Science Friday.

• 0:37Flora Lichtman?

  Today in the podcast, a new to us, deep sea alien.

• 0:42Speaker 03

  And within that proboscis, there are these chitinous lips, almost. And within that mouth is three cute little teeth.

• 0:55Flora Lichtman?

  Researchers found a new sea spider with a giant nose, leg cannons, and, most remarkably, a novel way of surviving in the lightless, freezing environment miles below the sea surface. These oceanic arthropods are powered by methane that seeps out of the ocean floor. Here to tell us more and how we're connected to these little beasts is Dr. Shawna Gofredi, professor of biology at Occidental College in Los Angeles, California. Shawna, welcome to Science Friday.

• 1:24Speaker 03

  Thanks, Flora. I was just grinning from ear to ear with that description. That was an amazing description of the research.

• 1:31Flora Lichtman?

  I'm so glad. I'm so glad we didn't botch it. Thank you. I have heard of methane-powered microbes, but now sea spiders? Please introduce me to them.

• 1:43Speaker 03

  Yes, so we have, for quite some time, actually wanted to understand whether certain animals can take advantage of methane on the seafloor. And just as you said, we only know that microbes can do it. And we are aware of some animals that can partner with some of those methane-eating microbes, but we've been interested in discovering others because we know that methane is coming from the seafloor, and it is a very high-energy molecule. And so we were on the hunt for unusual animals that might have been overlooked in the past, that might just have a different strategy than we had anticipated.

• 2:19Flora Lichtman?

  And how do they work with microbes to take advantage of methane?

• 2:23Speaker 03

  Yes, so what we realized is that they actually farm Methane oxidizing bacteria, so those that eat methane and convert it into CO2. And those bacteria were making biomass out of this carbon. And then the sea spider actually turns around and like farms and consumes the bacteria off of their body's surface.

• 2:43Flora Lichtman?

  Did you say farm?

• 2:45Speaker 03

  Oh, yeah, we know of many agricultural arthropods. Farming crustaceans, farming arthropods is not unusual. But what is unusual is we know of no other spiders that do this.

• 2:57Flora Lichtman?

  What's in it for the bacteria?

• 2:59Speaker 03

  Yeah, that's a great question. So clearly, the bacteria are being encouraged to live on the surface of the sea spider by the spider, no doubt. And so the spider is clearly enriching on its surface a special community. And so it is benefiting the bacteria to ride aboard.

• 3:19Flora Lichtman?

  That's why you say farming, because the spider is creating an environment that's good for these bacteria?

• 3:23Speaker 03

  Oh, you're absolutely right.

• 3:25Flora Lichtman?

  Wow, okay. And so how do they get the bacteria off of their bodies and into their mouths?

• 3:29Speaker 03

  Right, right. So that's a great question. It is very hard to do behavioral studies in 2,000 meters deep in the sea. And they're also translucent and they're tiny, like a centimeter in leg span. And so, to be honest, we've never actually seen them do this grooming behavior. So we just assume they're using that that large nose you spoke about is actually called a proboscis. And within that proboscis, there are these like chitinous lips almost. And within that mouth is three cute little teeth. And what we see from these, in the biofilm of bacteria that's on the outside of this spider, we see these little lawnmower marks where the bacteria have been uprooted and

• 4:11Speaker 03

  they're missing from this matrix of goo that they make to stick to the spider. And the width of that lawnmower mark is exactly the width of the mouth. And so, of course, it's, you know, it's circumstantial at this point, but we're pretty sure that that's how they're they're getting their farm.

• 4:28Flora Lichtman?

  Oh, my gosh. So they have a nose and within the nose, they have a mouth and within the mouth, they have tiny lips and under those lips, they have three itsy bitsy teeth.

• 4:36Speaker 03

  Exactly.

• 4:37Flora Lichtman?

  Oh, my God. That should be a SpongeBob character. I love it so much.

• 4:41Speaker 03

  For sure, for sure. So we haven't described these species yet. We have proposed a few species names. And I think a SpongeBob character would be the methane menace.

• 4:50Flora Lichtman?

  Oh, I like that. What are the other names that you're proposing?

• 4:53Speaker 03

  Well, we think, you know, methanophylla. So it has to be in Latin, of course. So that is

• 4:58Flora Lichtman?

  Snore. Yeah.

• 4:59Speaker 03

  Oh, but methane menace in Latin is methanominax, which actually I think is kind of, it's a pretty good one.

• 5:05Flora Lichtman?

  It has a ring. Yeah.

• 5:06Speaker 03

  It does.

• 5:07Flora Lichtman?

  You know, I think a lot of people might hear this and be like, oh, a deep sea spider that eats a bacterial crust with its nose. Thank you, but no thank you for this new information.

• 5:18Speaker 03

  Oh, for sure.

• 5:19Flora Lichtman?

  Shauna, why, why do you care about them? Like, what is the bigger picture?

• 5:23Speaker 03

  That's a great question. So I think that understanding biodiversity on the planet is supremely important. And, you know, we, we think that a tiny little spider on the seafloor might be useless, but every little cog in the ecosystem is important and they could be prey items for other organisms. So for example, at these methane seeps, we see all kinds of fish and crabs that we use as fisheries. And so rockfish, spider crabs. And so I think, I think they are probably pretty important.

• 5:55Flora Lichtman?

  Not to mention, we don't really want that methane in the atmosphere, right?

• 5:59Speaker 03

  Oh, you're absolutely right. So methane has a much higher warming potential. And it comes out of the seafloor. So you're, you're exactly correct that these animals and the bacteria, of course, that they farm are acting like a biological filter that prevents all of that methane from actually entering the overlying water column. And then of course, entering the atmosphere, which would be bad.

• 6:20Flora Lichtman?

  You know, for my whole career, I've heard this phrase that we know less about the bottom of the ocean than we do about the surface of the moon.

• 6:26Speaker 03

  Yes.

• 6:27Flora Lichtman?

  Is that still true?

• 6:28Speaker 03

  Oh, for sure. So there was a, a recent paper in Science that reevaluated how much of the seafloor we've actually explored, and it's less than a percent. And every time we're in a submersible or we have a robotic submersible looking at the seafloor, it's not that we just discover new species. We actually discover whole new ways of life.

• 6:49Flora Lichtman?

  When people see a new headline that's like, three new deep sea spider species discovered. Do you think that, you know, people understand what it takes to do that work?

• 7:00Speaker 03

  I suspect they don't. So it, it really is. A village, so it's expensive and it's time consuming and it is harrowing. Actually, our recent trip to Alaska, we took the Alvin to some of its deepest depths that scientists have taken it to, 5,000 meters, and it was extremely cold. It was rough seas. So it is not for the faint of heart when you're out there. So every little discovery is so meaningful.

• 7:26Flora Lichtman?

  Shauna, that is the perfect segue because on tomorrow's podcast, we are taking listeners inside that very sub on one of your deep sea expeditions, one of the expeditions that uncovered one of these methane powered spiders, right?

• 7:41Speaker 03

  Mm hmm. Exactly. Yes. Off of the Aleutians.

• 7:44Flora Lichtman?

  It's an episode of the leap that I made with the hypothesis fund. So buckle up because we are about to go for a hair raising ride in the Alvin submersible. That is tomorrow on the podcast. Thanks, Shauna.

• 7:58Speaker 03

  You're welcome. Thanks for having me, Flora.

• 8:04Flora Lichtman?

  Thanks for listening. Don't forget to rate and review us if you like the show. And you can always leave us a comment on this segment on Spotify. We'd love to hear from you. Today's episode was produced by Dee Peterschmidt. I'm Flora Lichtman. Thanks for listening.