Science Friday - Spiders, Quantum Supremacy, Missouri Runoff. Oct 25, 2019, Part 1

Episode Date: October 25, 2019

Spiders were one of the first animals to evolve on land. And over the span of 400 million years of speciation and evolution, they’ve learned some amazing tricks. One of their trademarks? The strong, sticky substance that we call silk—every spider produces it, whether for weaving webs, wrapping prey, or even leaving trails on the ground for potential mates.  But every silk is unique, each with different chemistry and different physical properties. Even a single spider web may use multiple kinds of silk. So how did spiders develop these wondrous fibers? We hear from Cheryl Hayashi at the American Museum of Natural History, Sarah Han at the University of Akron, and Linda Rayor at Cornell University about their work.  Plus, a "dead zone" in the Gulf of Mexico has states along the Mississippi working to reduce nutrient runoff. Science and environment reporter Eli Chen from St. Louis Public Radio tells the us the State of Science. And, Google says its quantum computer has achieved in just 200 seconds what would take a supercomputer thousands of years. But IBM is pushing back. Sophie Bushwick, technology editor at Scientific American, joins Ira to talk about what this means and other stories from this week in science. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Ira Flato. Oh, in case you missed it, the quantum supremacy has arrived. Yeah, at least according to Google. What does that mean? Well, Google says its quantum computer solved a problem in just 200 seconds that would have taken the best supercomputer 10,000 years to complete. But the pushback has already started. Here to fill us in is Sophie Bushwick, technology editor at Scientific American.

Pushback starting. Oh, yeah, absolutely. I mean, this goes back. This is a big, big breakthrough. This is Google's, Google has compared this to the first airplane flight in terms of the significance of this finding. Yeah. So this is a big deal, which means there's a really high standard of proof that Google has to meet to say that we have achieved quantum supremacy. So there's already been pushed back against that claim. Start at the beginning. What is the quantum supremacy and how does that start? So the whole appeal of a quantum computer is that it can solve certain types of problems exponentially faster than classical computers. And the problem is it's really hard to build a working quantum computer. So a lot of different tech companies have been struggling with this conundrum, and none of them have managed to get a quantum computer that could really fulfill the promise of solving these problems super fast. So that's what Google claims they've done. They say this is a problem.

Your regular computer would take thousands and thousands of years. we've done it in seconds. Almost immediately, IBM started working on, they said, well, could this type of problem that you've solved be actually solved much faster by a regular old computer, not a quantum one? And they have released what they say is an algorithm that could solve it in just two and a half days instead of 10,000 years. So they're saying, you know, Google's achievement isn't quite as big as they're making it out to be. And there's no quantum computer around the corner for everybody to buy it. No, I mean, even Google's quantum computer is, right, it's solved this one problem. It's not about to really, it's not about to break down all of these barriers that quantum computers could eventually maybe do.

Because one of the exciting things, one of the types of problems that quantum computers could be very good at solving is factoring big numbers, which is a key component of most modern encryption methods. So the idea is that if a quantum computer could solve these problems much better than a classical computer, they could crack most modern encryption. And that's the theory. If Google is right, then the encryptions are not that secure anymore. Well, down the road, I'd say encryptions are not that's correct. Right. This isn't, they haven't actually, the type of problem that the Google's quantum computer solved is not the encryption problem. But the idea is that this is the first step on a path toward that. And in fact, That just because even if they do reach that point, which could be years in the future, researchers are working on new methods of encryption that you couldn't crack with a quantum computer. So it's not definite that encryption will be destroyed forever. Spy versus spy.

Very much so, yeah. Let's talk about another continuing story that the researchers have discovered that algorithms can be biased. Whoa. Right. This is just another example of the ways that you can inadvertently put bias in an algorithm. And this is actually a health care algorithm that's used to determine, is this person at high risk of being ill? And so hospitals or insurance companies can make sure that these high risk patients are eligible for extra care to kind of stave off some of these more expensive complications. And researchers were looking at the algorithm and they realized that for black patients to be classified as high risk, they ended up being much sicker than the white patients who had similar risk scores. And the reason what this comes down to is the algorithm was using health care spending as a proxy for health care needs.

And the fact is that a lot of black patients are from a lower income bracket. And so thus would have less money to spend on health care. And the other issue is that a lot of black patients face implicit bias from doctors, which makes them less likely to trust their doctors and less likely to go to the doctor and say, hey, I have this problem. Can you help me? And can I pay for this for treatment for this? Can they fix the algorithm? That's what the researchers are hoping to do. They've said they weren't doing this as sort of a gotcha attempt to sort of break down the algorithm. What they want to do is make it fairer. So the issue with all these algorithms is you put data in, you get a result out, but you don't know how the algorithm reached the conclusion it did. So it's really important that companies that are relying on these

algorithms test them thoroughly and make sure that you can eliminate bias as much as possible before you actually start using it. Also, I've got to go to what I said in the introduction. Researchers taught rats how to drive. This is a great video that is up on the web. Yes, this is an amazing study. I encourage everyone to look up this video. They basically took, it looks like a big plastic box that they put on wheels and they put the rat in it.

And there's these copper wires that the rats can grab. And grabbing different wires steers the car in different directions. And so you can watch these rats driving their car around, like chasing down food rewards. And apparently they were also saying, hey, how does this affect the rat's mood? So they looked at stress hormones and anti-stress hormones in the rat's droppings. And they found that a rat that got to drive itself around had much lower stress than a rat that was sitting in a remote control car. So the rats, what that says, enjoys driving. It wants to drive. Yes. So it's possible maybe rats just love the freedom of the open road.

Or what the researchers have suggested is actually happening is that learning a new skill is satisfying. And it's that satisfaction that is making the rats less stressed and happier. See if I can squeeze in one last story about CRISPR to fight viruses? What do the researchers do there? So we know that you can use the CRISPR technique to kind of slice and dice DNA to do genetic modifications. But what these researchers said was what if we could use it to attack RNA viruses? So they programmed an enzyme related to the enzyme used in CRISPR to attack RNA in cells outside the body. And what they found was they targeted three different viruses.

And for all three of them, this technique was able to reduce the transmissibility of the virus. it was less likely to spread outside the cell. Wow, so there's some future about that. You could absolutely use, this is really exciting, but it's still in the very early stages. So it'll be interesting to see them test this in animals next. Isn't that always the last words of a report? More research is needed. More research is always a good idea, I would say.

Thank you, Sophie. Sophie Bushwick, technology editor at the Scientific American. Thank you. Now it's time to check in on the state of science. This is KERNNNO. St. Louis Public Radio Radio News. Local science stories of national significance. The Gulf of Mexico has a dead zone,

and I'm not talking about some sort of Halloween tie-in or an upcoming horror movie. It's worse than that. It's an area in the Gulf that's been starved of oxygen and the result of too much fertilizer, an animal and human waste flowing into the Gulf. That effluent comes upstream, comes from upstream where the states along the Mississippi River

dump that stuff into the river, and so those states are working to reduce nutrient runoff. Joining me to talk about Missouri's approach to that problem is Eli Chen, science and environmental reporter at St. Louis Public Radio. Always good to talk with you. Yeah, thanks for having me, Ira. So I talked about fertilizer runoff, but they're all kinds of runoff. What are we talking about here?

Yeah, so what we're talking about the dead zone, the Gulf, the majority of runoff that contributes to that is from farms and to a lesser extent from stormwater in urban areas and discharges from wastewater treatment plants. And that contains nitrogen and phosphorus, which is, you know, good for growing crops, but too much can be a bad thing. And when the nutrients get to the Gulf, what happens there? Well, actually, in any water body, too much nitrogen and phosphorus create these massive alkylumes, these huge growth of algae that are usually green in color. And they're often described as looking like pea soup or spilled paint on water.

And, you know, when the bloom dies and the algae ross, that depletes oxygen from the water creating these dead zones. So it's a pretty dramatic process. And this occurs all over. You can see the results. Visually, you can see that. Yeah, yeah. You know, the USGS has some data on this where they've measured, where they've measured nitrogen and phosphorus coming from states all around the Mississippi River Basin. I will say that in reporting my story, it was the data, the most recent data is from.

2002, which is not ideal to work with, but it did show that Missouri is a major contributor to this issue. You spoke to a farmer about his fertilizer application, and he said it wasn't just an environmental concern for him, but affected his bottom line. We do realize if we put too much on, it's going to go somewhere, and we don't want to be paying to kill the fish in the Gulf. Yes, so that's Mitchell Rice. He's a farmer in northern Missouri. He's actually made a lot of effort to reduce runoff from his fields like planting cover crops, for example, and those are often cereal crops that reduce soil erosion. But farmers do have to constantly weigh whether a change their practices could yield, you know, could affect their yields and profits

that year. And as Mitchell Rice told me, there are a lot of farmers, you know, who are operating in the red lately due to a number of factors. So they need some convincing, you know, to do these conservation practices. And like he says, it's not something I want to do, but they don't have a choice in this matter. Yeah, that's correct. So what is Missouri then trying to do about this? Do they have any incentive or tax programs that they can suggest? Yeah, so the state's main strategy is to use this sales tax program that generates funds that are used to help farmers pay for conservation practices.

So those are like the cover crops that Mitchell Rice has planted on his farm. Is this a volunteer thing or is it a mandatory? Yeah, it is voluntary for farmers to use these conservation practices, and environmentalists have complained that, you know, Missouri really needs to put limits on nitrogen and phosphorus to really make a difference. And the impact of the sales tax program really hasn't been measured yet. Yeah, and that's kind of a thing. People want to know about results and whether these things are working or not, and we don't have a way yet to judge the effectiveness. Yeah, the state has plans to measure that, but, you know, at the most of the most of the most of the most of the most of the most of the. moment we haven't seen much. Are there any larger structural issues that could help this problem with

how water flows into the Mississippi? Yeah, so in my reporting, I did speak to a nature conservancy scientist who said that restoring wetlands and using nature-based solutions that reconnect the Mississippi River to its floodplain could help prevent runoff. But at the moment, that research has yet to translate to any actions that on a large scale could help clean up the Mississippi River and the Gulf of Mexico. Yeah, it's always, we'll see what happens, you know, see what happens, see how long this goes. It is a very complicated problem. It's an old story. Eli Chen, Science and Environment Reporter at St. Louis Public Radio. Thanks for talking with me today. Thank you, Ira. We're going to take a break and when we come back, spiders. Oh, what a tangled web they weave. You know, Halloween season means

it's time to celebrate spiders as only Science Friday can. We're going to do the Science Friday twist. I mean, there's some facts about spiders. You know, they put out all the things. different kinds of silk, depending on what part of the web they want to weave? It's really interesting stuff about spiders. Stay with us. No arachnophobia. I promise who that. We'll be right back after the break. This is Science Friday. I'm Ira Flato. Do you ever look at a spider web? I mean, really look at it. Whether it's a beautifully organized orbweaver web, could be a funnel or messy, fluffy cobweb. There's a lot that goes into making that web. Right. There's the design.

in shape, of course. But then there's the material. Spider silk is amazing stuff. It's stronger than steel, but also stretchy, sticky, and a deadly weapon for catching prey. And even more importantly, there is no one recipe for spider silk. Many spiders actually have several kinds of silk that they make, both for web-building purposes, but also signaling to mates or even just hanging out in case they fall from their perch. And then they do it. It's all really, really interesting. And here to spin the tale about the wonders of spider silk, Dr. Cheryl Hayashi,

curator and professor of comparative biology at the American Museum of Natural History here in New York. Hi there. Hey there. Hi. Let me give out our phone number 844724-8255 if you want to talk about spiders and their webs. You know, in just reading the kind of work that you're doing, I had no idea about the spider silk and that, you know, there's different kinds of it? Let's talk about what it is first.

What is spider silk on a material level? Well, if you look at spider silk, really zero in on it. It's almost entirely protein. So we're talking many, many, many, many individual protein molecules knitted together to make a silk fiber. Wow. And the spiders don't just use it for spinning webs, right? Oh, no, no, no. That's just one of the functions they have for spider silk. They use spiders, depending on the spider, they use it to make homes, drag lines,

females wrap up their eggs in it. As you mentioned earlier, they make these silk lines that they put pheromones and they put scents on it. They also use it to sail through the air. Wow. And silk is one of the prerequisites of a spider being a spider, right? Oh, yes, definitely. You can't be a spider without making silk. Does this mean that they all evolved from one silk spinning arachnid, perhaps? Yes, that's what we believe based on the fossil record. And, you know, when we look at all living spiders today, they all have the ability to make at least one kind of silk.

Now, when you say one kind of silk, that implies there are lots of different kinds of silk for use in different sections of the web? Oh, yes. So there's so many different kinds of silk. silk. So first of all, most species make multiple kinds of silks. Many species make up to seven different kinds of silks. And when you look at, let's say, a typical orb web, that's, you know, the Charlotte's web type spider, the wagon wheel-shaped web. When you look at that spider, there's usually

five kinds of silks went into making that web, sometimes six. And how does the, how does the spider produce all those silks from its one body? Well, what I work on is, yeah, exactly that. How are they able to do that? Well, if you look inside a spider, there's many, many, many, many sulkland, sometimes dozens, usually hundreds, in some cases thousands. And each sulkland looks like, picture a balloon. And so a sulkland would start off kind of looking like a deflated balloon,

and the wall of the balloon would be these cells that can make silk protein. And those cells make silk protein. And the silk collects inside the balloon, and they just absolutely fill it up, and you get a nice, big, puffy silk gland inside a spider. I remember now there's hundreds of these in a spider. And that's where they get the silk from. And then the neck of the balloon make that really long, and that becomes like a little channel, a duct, that leads to the outside of the spider.

And that's how the liquid silk from inside ends up on the outside of the spider spun into a fiber. And when you have all a different kind of silk, what are their specific purposes in the web? Well, there's going to be one kind of silk that will be making the frame and the radii of an orb web. So that's one kind. There's another two silks that are used to make the sticky capture spiral. So one silk makes the thread and the other one makes a wet glue that goes on top of the thread. There's another silk that's used just to stitch pieces of silk together.

We call that attachment silk. And there's another silk that's used as a construction scaffold. The spider puts it out when it's time to build a web and actually removes it while they build the web. And when spiders remove silk, they actually eat it. Wow. They recycle. Oh, yes.

Our number 844724-8255. We had a question from Ingrid on our Science Friday Voxpop app. Why do some spiders like widows make messy web? that are bad for catching bugs, while others like orb spiders make beautiful, elaborate webs that only last one night. Oh, okay. Well, I think, first of all, beauty is in the eye of the beholder,

and I actually think black widow webs are quite beautiful. So actually, black widows are descended from orbweb-webing spiders. So black widows actually can make all the same kinds of silks as an orbweb-web-web-web-weaving spider. they've just sort of changed the architecture of their web. And they're actually very, very, blackwater webs are actually very, very good at catching prey. The sticky part of their web is actually at the very, very bottom of the web, and they remake that bottom part every single night actually multiple times during the night.

And the question about, you know, why do some spiders have to remake their web? Well, when insects hit the web, it damages part of the web. And if a web gets too damaged, then it's not a good net anymore. So it's just like, you know, if you repair a fishing net. So some spiders will repair their webs. Others will just say, ah, time to make a new one. And they'll take the web down and eat the silk, and then they'll spin a new web. They're really busy all the time.

Well, they're busy when they're making the web. But, you know, these web weaving spiders are sit-and-weight predators. So when they're waiting, they're actually quite still and just, you know, hanging out. You said one part of the silk was used for capturing their prey. What's different about that part of the silk or that kind of silk? Capture silk is different from, let's say, the frame of a web, because capture silk is very stretchy and sticky. So the capture silk on a web, it allows the fibers, the silk fiber,

the silk fiber actually stretches, so rather than sort of break like a more stiff fiber would, it actually stretches, which allows the web to absorb the energy of a flying insect. And also, insects literally stick to the glue that's on the capture spiral. Let me see if I can get a quick calling before the bottom of the hour. Dorian in Swampscott, Massachusetts. Hi. Hi, how are you? Hi there.

Go ahead. So I was just calling because my daughter is a nature lover and she actually inspired our entire family to fall in love with this giant spider that lived in a window frame and built a sort of tubular web. And eventually we all fell in love with Sheila. We named her after Lord of the Rings. And we would check it daily to make sure she was getting fed. And essentially over a couple of years, we noticed she was still there. but we don't know. We have actually one comment was the sad part was the landscapers accidentally killed her,

and we were all very sad. But the other part was, was this the same spider living there year after year, or was it another spider that adopted this long tubular web and made it their own home? Great question. Thank you. From what you're describing, I think it was the same spider. So spiders, depending on the species, they can live year after year. In fact, some spiders can live over 20 years.

And there are other spiders that, you know, will live less than a year. But from what you're describing, I think it was one of the more long-lived species, and that probably was her web. 20 years? Which spider in particular? Oh, yeah. Stuff that we would see around our house? Well, there would be, you would, spiders like that would live, you know,

multiple years really long. There tend to be these trapdoor spiders and also tarantulas. Wow. Let me go to Erie, Colorado. George, hi, welcome. Oh, hi, yeah. You know, you often see a horizontal strand that a web is suspended from, and it's several feet apart, and I do not understand how spider can do that. Yeah, that's amazing.

So spiders actually are able to, they're actually able to release silk into air currents. and these air currents are often much more subtle than we might be able to detect, and the air current will actually, you know, a little wast of breeze, will take a fiber from the spider to, you know, a distant branch. And when that silk line hits the branch, the spider can, you know, give a few tugs and can actually walk across. And then the spider will walk back and forth and kind of strengthen that's the line. Wow, that's just amazing.

Thank you, Dr. Hayashi, for taking time to be with us today. Oh, sure, thank you. Dr. Cheryl Hayashi, curator and professor of comparative biology at the famous American Museum of Natural History here in New York. And you can learn more and see our new video about her work from producer Luke Groskin. This is an amazing, amazing. Luke does great work. I'm telling you, this is at the top of the list.

Go to our website, ScienceFriday.com slash spider silk. Slash spider silk on our website, ScienceFrily.com. Now I want to bring in another researcher to, to listen on the spidey engineering of one very special spider web. Normally, you know, when an insect hits a spider web, those strong, stretchy silk fibers give and give and give until the insect is slowed to a stop, begins to get tangled. But the triangle weaver spider has a slightly different tactic.

Here to explain more is Sarah Hahn. She's a PhD candidate in integrated bioscience and biomimicry at the University of Akron in Akron, Ohio. Welcome to Science Friday. Hi, Ira. Thanks for having me. Tell me about the triangle weaver spider. What's so special about its web? Okay, so the triangle weaver spider is this little spider that lives out in the forest, often in pine forest, and you can find it here in Ohio.

So instead of the orb web that Cheryl was just talking about, it makes a triangle-shaped web. And what's cool about it is that it stores energy in this web, kind of like a slingshot or a bone arrow, and it uses this stored energy to help catch insects. And how does it do that? Okay, so what the spider does, if you picture a triangle-shaped web, the spider goes to one corner of the web, and its head is facing towards the triangle part, and it walks backwards with his back legs, and it pulls the web tighter and tighter.

Just imagine, like, pulling a slingshot back further and further, and this loads the web with elastic energy. So the web is, like, pulled taut, and the spider is holding it under all this tension. When an insect hits the web, the spider senses that and it releases the web. The web springs forward all that released energy and the web sort of moves across the insect, entangling it in these thicky capture strands of silk.

Wow. So what keeps the spider itself from not flying off on the air when this happened? So it is, the spider does move forward with the web, but it is attached, it's attached a line of silk to its spinnerets at the back near its back legs. it's usually attached like a twig or a branch. So even though it is moving forward to the web, it's not, you know, being flung off into space. Wow.

So how quickly does this happen? And can you give us some idea on a human scale what it would be like for a person? Sure. So the spider is accelerating at around, well, the max we found is 770 meters per second squared. So one way to think about this, if you think about, you know, in like car ads,

they say, you know, zero to 60 in five seconds. Here, this would be 0 to 8,600 miles per hour in five seconds. Wow. That's a pretty fast acceleration. So why would this be more effective than just letting the insect get tangled the traditional way? So the traditional way, the insect is tangled, but the spider has to get to that insect really quickly, usually in just a few seconds where the insect may struggle free because it doesn't want to be eaten. With this process, the spider senses the insect, and it often reacts in just fractions of a second,

and that lets the web go and starts the tangling process. So it's like the capture process has been started very quickly and without the spider having to actually cross the web and physically grab the insect. So it's safer than to the spider. It is safer. And what's interesting is this family's spiders does not have venom, So maybe that's another reason that they might have evolved it. Wow.

Let me just say, I'm Ira Flato, and this is Science Friday from WNYC Studios. Talking with Sarah Hahn from the University of Akron. What got you interested? This is so fascinating. How do you discover these things? The spider itself. Yeah, and how it acts and catapults and all that kind of stuff. Do you have to do a lot of spider observation?

It is a lot of spider observation. So this was actually my first project when I first first. started the program in Dr. Todd Blackledge's lab. And I was just starting, because I have a background in entomology, which is insect, so I didn't know that much about spiders. So he's like, you know, just go into the woods, observe spiders, just start doing things. So I found these little spiders in these triangle webs. And I was like, you know, what are these?

And he's like, oh, these are triangle weavers. They, you know, do something. And they have an unusual prey capture strategy. Why don't you just start looking more into them? So I started doing some experiments, and we noticed this, I mean, the cool behavior had been observed before, but not really quantified. And then one of my professors and I guess colleagues now, Dr. Henry Astley, was like, hey, that's an example of, like, external power amplification.

It's storing energy in the web. And that sort of brought us further and further. Well, then if you're talking about, you know, power amplification, whatever, could you look at a spider web as actually a tool? You know, we talk about animals using tools and using their intelligence to build tools is the web a tool that the spider has learned how to use? I would personally count the web as a tool because a tool in animals is like classically defined as something external to your body that you're using to affect a change on the

environment. And even though the spider is creating the web, it's still using it external to its body, much as we would like maybe braid a rope out of our hair so that we would still count that as a tool. You see if I can get a call in before we have to go. Jonathan in Minneapolis. Hi, Jonathan. Hello. Hey there, quickly.

All right. I work for 3M on all sorts of sticky stuff there, and I was curious, what is the glue or the adhesive on the spider webs made of? So in spiders that use liquid glue, it's made of salts and low molecular weight compounds and just a bunch of other things and a lot of water also. For the triangle spiders, they actually use a dry adhesive called Crippolate silk, which is just like little, very fine puff silk that mechanically entangle the insect. So different spiders use different kinds of adhesive. You know, 3M invented post-it notes.

So maybe they're taking notes from you about the next kind of glue they would learn. Kind of spider, tell us about making glue? Do you think we can learn something? Oh, yes, a lot of people, even in the lab that I'm in, are always looking to glue for a better adhesive that responds well in different humidity, which spiders do really well. Yeah. Well, it sounds like you have an exciting job, an exciting career ahead of you.

I hope so. Are you going to concentrate on spiders as you? I would like to, but we'll see how it goes. There's so much in the natural world that's exciting to study. Could not say it any better. And I want to thank you for taking time to be with us today. Thanks for having me. And thanks for all the hard work you and your team do.

Thank you. Sarah Hahn, who soon will be, have her Ph.D. We hope she's a PhD candidate integrated bioscience and biomimicry at the University City of Akron in Ohio. We're going to take a break and our spider brasion. See what I did there. It's not over. We'll talk about social spiders.

Yes, they exist. Answer your questions. Have lots more dad jokes. So stay with us. We'll be right back after this break. This is Science Friday. I'm Ira Flato. I want you to picture a spider now.

Any spider. Maybe she's hanging out on a web waiting for dinner to land there. Or maybe he's prowling the ground, hunting a mate. But chances are you're not thinking about a colony, right? You see in your mind just one spider alone like we usually do on the web. There's a reason for this picture of the solitary spider. Most of them are loners. It makes sense.

They're predators, and they're more likely to eat a fellow spider than to cuddle with one. But my next guest researcher says there are rare exceptions. Spiders that live in colonies of siblings. And she says the family that stays together, seems to eat better together. Here to tell the story and answer some more of your spider questions is Dr. Linda Rayer, senior lecturer and research associate in entomology at Cornell in Ithaca. Welcome to Science Friday.

Oh, thank you so much. That was a great intro. Was it? Did I get it right? I would say the family that stays together, prays together. And you work with a group of spiders from Australia, the Huntsman Spiders. What are they like? Oh, huntsmen spiders are lovely spiders.

Huntsmen are medium to absolutely huge spiders and often very attractive spiders. And the huntsmen are characterized by having legs that are called latrugate. So they essentially go out to the sides, which mean that they can run forward very rapidly, but they can run as rapidly. can run as rapidly sideways. So they're really cool spiders, no webs at all. The spiders that I study live in a number of places, but the main group that I study that I sent you a photo of is Delaney Canceritis, which is found in Australia under the bark of dead trees,

especially acacia and a few eucalypts. and so they're quite flattened, kind of dorsalventrally flattened, and they're fast and they're beautiful. And they live together in a colony? Yeah, they live in a really interesting family group. So each colony is founded by an adult female who has up to five different clutches of youngsters. And what's really cool about these guys is that her offspring stay with her until they reach sexual maturity at about a year. But we're talking spiders that are about the size of the palm of my hand. So they're not dispersing until they're, you know, absolutely marvelous predators who could easily kill one another, but don't.

And so what happens? Why is that? Why don't they? That is the eternal question when you're setting social spiders. There are actually lots of benefits by living in groups for social spiders, both mine and other people who are studying even more socially complex spiders. With my spiders, they live in a protected retreat with mom defending it and with the older spiders. defending it. The retreat is silked in so big bull ants or other predators can't easily get in to get them. And mom is actually fending off other huntsman spiders or other predators that might try to get in.

It sounds like mom is keeping the peace there. Mom is definitely keeping the peace. And also, my former grad student, Dr. Eric Kiyip, did wonderful work where he found that spiders that had older siblings in the group were in far better condition than the ones that didn't have older siblings. And it's really obvious why. What happens with the social spiders is they're able to catch large animals or able to catch larger prey, which they're willing to share with their younger siblings. So these younger animals get access to far, far bigger prey than they would on their own. So it's a good deal for them. And I've got to admit the older siblings don't necessarily want to share their prey.

If they catch it away from the retreat, they'd rather eat it and then come home at dawn. But they're not totally active. But what's clear is that lots of food is coming into the retreat that littleer animals get access to and are able to share. Why did these spiders adapt to be social when so many other species stayed solitary? That's one of the central questions of what I'm asking, and I'm not sure I have an easy answer. My collaborator in Australia, Dr. Dave Rohl, has suggested that with climate change in Australia, there were less and less places, these thin, protected diurnal retreats that they could live in. And with climate change, there were relatively few places that they could live, and so there were advantages to staying together. That's interesting.

Eric's dissertation showed another possibility. What we know is that for these spiders, there just aren't enough retreats to go to. So, you know, it looks like there's a lot of places, but what we've done is we've counted how many potential places young spiders can disperse to. And for these spiders, there's nowhere to go. It's between 100%, excuse me, the habitat is between 100% saturated and the absolute best site we've ever seen had about 82% saturated. So what's happening is these adolescent spiders are sticking around at home because if they

disperse to found their own colony, they've got nowhere to go. And we've taken measures between 50 and 100 meters, and there's nothing. There's literally no place that these spiders can move to. So what they're doing is they're staying at home until they reach sexual maturity, until they're larger and tougher and feistyer. And then bigger animals try to take over other animals' colonies. So Eric's research showed he put out nest boxes, and what he showed is bigger adult females were taking it over from smaller females.

So there's a lot of competition. I'll bet. I also, I hear that tarantulas are among your favorite spiders. Tarantulas are among my favorites. Why is that? So, you know, people are, I think, more scared of tarantulas than any other spider. What makes them your favorite? Interesting.

Huntsmen are my favorite, but tarantias. Tarantulas are second. I think tarantulas are really big. I had no idea. When I started teaching, I brought spiders in to my course because they're big enough that I could show things. And turns out they're incredibly diverse. Many are arboreal. I'm especially a sucker for arboreal tarantulas that are just gorgeous and have a very different build than the terrestrial tarantulas. I've gone on a phase where I just like blue tarantulas right now. And it turns out there are a lot of gorgeous tarantulas, many of which also live in groups. I'm stuck on social behavior. So I'm particularly interested in spiders that live in family groups with their mother and with other adults in a colony. And I'm afraid a bunch of the social tarantulas or the, yeah, I'll go with social tarantulas, don't actually do that much. That's totally cool, but enough of them do. Recently, I got a colony of, they're called Catrota Island Blue, but monocentropus balfouri.

And they're siblings, and they dig a burrow underground, and then they pile in like sardines on top of one another when they're not out feeding them. wandering around. It's crazy. That's crazy. We have some calls. Let's see if we can get to them. Sure. Let's go to Linda in Portland, Oregon. Hi, Linda. Hi there, Ira. Thanks for taking my call. Welcome. Yes, I have a question. I, for the past few weeks, have been watching this spider that's on my back porch and on a Japanese maple that's in a pot on my back porch. Originally, it would build its web and sometime during the day, sometimes at night. And then about two weeks ago, I noticed that although it used to just roll itself up in a leaf at night, I suspected to keep warm, now it is just wrapped up in that leaf.

And I'm wondering, is it hibernating because it hasn't come out in a while? And I'm worried because the leaves are starting to fall off the maple tree. So what's going to happen to this little spider? Can I answer? Sure, please. Sure. So a number of different options. It's possible that what your spider has done is wrapped herself in a retreat so that she can molt and she'll be protected during this risky period and she'll grow to another instar.

The more likely option is that she's laid eggs in this leaf and she's about to die over the winter. And so you've got egg sack in there. I think those are the main options you've got. Hmm, that's quite... But the truth is, is orb weavers die this time of year. It's sad, but they leave eggs that overwinter. You mentioned the, I think when we began to speak, and we were talking about these social spiders.

Did I hear you say that they don't build webs? They do not make web. But the definition of all spiders, we heard from one of our other experts, is that they have the silk. They do make... So your spiders do have silk also? All spiders produce silk of some sort.

But a very large group of spiders, including jumping spiders, wolf spiders, huntsman spiders, and crab spiders, have given up using a prey capture web. And so all spiders use silk to bind their egg sacks. They might use it for drag lines to, you know, as safety ropes. and any number of things, but they don't all use webs to capture prey. That answers that question. And I actually prefer animals that don't use silk. Okay. Well, we had a message from Rod on our Science Friday Vox Pop app about a cool spider living in his house.

Yes, we have these little black and white crab-looking spiders that live in our house. They eat aphids and small insects and other spiders that bite us. And so we let them have the run of the house. They're really kind of cool. You find, Linda, you find spiders are kind of cool, too, right? I absolutely find spiders are cool. Once I assigned my spider biology class to record what spiders were in their dorm rooms, you know, identify what the spiders were in dorm rooms and apartments all over Ithaca, New York.

And, of course, I did it myself. And when I realized we had 85 spiders, mostly baby cellar spiders in the, house, I realized I needed to do something different, but largely they're good. I'm Ira Flato. This is Science Friday from WNYC Studios, talking with Dr. Linda Rayer, a senior lecturer and research associate in entomology at Cornell University about spiders. Let's go to the, oh, so many people. Marty in San Jose. Hi, Marty. Hi, Marty. Hi, good morning. I took a trip to the Amazon a few years ago, included camping and woke up in the morning with tarantias. was crawling all over the mosquito netting, which was a bit startling. The question I had was,

how do spiders avoid ensnaring themselves? And the other question is, is there any difference in the web or silk between poisonous and non-poisonous spiders? Okay. As far as I know, there's no difference in silk between poisonous and non-poisonous spiders, at least, as your previous speakers mentioned, there's different kinds of silk that different kinds of spiders have. But if you were to look at something like cobweb spiders, as far as I know, there are absolutely no differences

between a black widow and a house spider, which is not venomous to humans. Do you think that most people don't appreciate the spiders living in their garages and basements and things like that? I would think that they would be less appreciative of the insects that the spiders are feeding on in their houses. So I think spiders are option, are awesome to have in your house and certainly in your garden. So if the spider is there, then it may be eating predators that you don't like and you don't want to have around. They're certainly eating prey.

People ask me why they have big nurse who have spiders or wolf spiders in their basement, and essentially it means that there's cracks in the foundation that the spiders are getting through. So it's an indication that you have other things coming in. You know, we talk a lot about the black widows, the brown recluse, the spiders people are scared of. Give me an idea of some spiders that we can look for in our backyard yards, and we might find less intimidating. Well, certainly the black and yellow garden spider, Argyapia Rancha, is gorgeous. It's a stunning orbweaver that uses Stable Menta or those zigzags in the web, possibly to attract prey, possibly not.

But beautiful spider. I think jumping spiders, you could start a fan club on the Tornel campus of jumping spiders. They're like the primates of the spider world, really quite smart, good vision. They'll follow you. You know, they'll pay attention to you and look around to see what you're doing. So the jumping spiders are awesome. Personally, I love having, you know, most of us are not going to find tarantulas in your backyard, but they're awesome when you do.

Do they make good pets? They're actually marvelous pets. They're not supremely active. pets, but a number of them do really interesting things. All right. I'm going to leave it right there because we're running out of time. Thank you for your work, and thank you for all that knowledge that you gave us about spiders. Dr. Linda Rayer, Senior Lecturer and Research Associate in Entomology at Cornell. Thank you for joining me today.

Thank you very much. It was a pleasure. And we asked you, our listeners, to tell us about your spider friends this week, and you heard some of them on our Science Friday Vox Pop app. We want you to go out and observe. your moths. Tell us about the moths that live near you and your questions about them on the Science Friday Vox Pop app. And to our San Francisco fans, we're coming to town in just a few weeks to talk about building ethical artificial intelligence, environmental justice, and we'll have live music and video from KQED's Deep Look series too. Here's the date. Circle it. Mark it.

Saturday, November 16th at the Sydney Goldstein Theater. Tickets and info at Science Friday dot com slash San Francisco. Let me repeat that. We're coming out there. Saturday, November 16th, Saturday night. It's going to be a live event at the Sydney Goldstein Theater tickets and info, Science Friday. com slash San Francisco. Charles Berkowitz is our director, senior producer Christopher Talata.

Our producer, Alexa Lim, Christy Taylor, Katie Feather, and Ella Fedder. And we had Katie Feather and Elefetter. We had technical and engineering help from Rich Kim and Kevin Wolfe. BJ Leiderman compose our theme music. And we're up there all week on social media. Every day is now Science Friday. Have a great holiday weekend. Trick or treating.

I'm Ira Flato in New York.