Science Friday - Omicron Variant, Quantum Computing, Xenobots, SciFri Trivia. Dec 3, 2021, Part 2

Episode Date: December 3, 2021

Decoding Quantum Computing The computer chips that are delivering these words to you work on a simple, binary, on/off principle. There’s either a voltage, or there’s not. The ‘bits’ encoded by the presence or absence of electrons form the basis for much of our online world.  Now, physicists and engineers are working to create systems based on the strange rules of quantum physics—in which quantum bits can exist simultaneously in a range of possible states, and two separated bits can be linked together via a phenomenon known as entanglement.  If practical quantum computers can be constructed, they have the potential to solve difficult types of problems—like finding the optimal route connecting a list of a few hundred cities, for instance. However, vast engineering challenges remain. A. Douglas Stone, deputy director of the Yale Quantum Institute and Carl A. Morse professor of applied physics at Yale University, joins Ira to give a primer on the disruptive technology of quantum computing, and where this research might lead.       Diving Into The Strange World Of Xenobots Just under two years ago, Science Friday reported on the strange world of ‘xenobots’—structures designed by an algorithm and crafted out of living cells taken from frog embryos. Those tiny constructs could slowly wriggle their way across a petri dish, powered by the contractions of frog heart cells. Now, the researchers behind the bots have created a new generation of structures that can swim—and, if provided with additional loose frog skin cells in their dish, organize those cells into clumps that eventually begin to move on their own.  Josh Bongard, a professor of computer science at the University of Vermont and a member of the xenobots research team, joins Ira to talk about the advance in what he likens to living wind-up toys. The work was reported this week in the Proceedings of the National Academy of Sciences. Bongard and colleagues say that they were interested in learning more about self-replicating systems, and the various factors that go into either speeding up or slowing down a system’s ability to self-replicate. They’re also interested in exploring whether such cellular systems might be able to do useful work. However, fear not—Bongard explains that without a ready supply of loose frog skin cells, these bots peter out.     What We Do—And Don’t—Know About Omicron This week, the Omicron variant was detected in the United States, with the first case identified in California. The announcement joins a rush of news about the latest coronavirus variant: Last week, South African researchers first identified and then sequenced the variant. Since then, scientists all over the world have been working overtime, trying to understand this heavily mutated new strain.  Omicron has 32 mutations in the spike protein alone. But more mutations don’t necessarily mean it’s more contagious than the Delta variant, or more likely to evade the vaccine. Scientists still need a little more time to figure out what these genetic changes might mean for the pandemic.  Katelyn Jetelina, assistant professor in the University of Texas School of Public Health talks with Ira about how scientists are compiling data on omicron, both inside and outside of the lab. Jetilina is also the author of the newsletter, “Your Local Epidemiologist.” To hear more of Jetilina’s thoughts on the latest updates, read her explainer on what we know and don’t know about Omicron.     A 30th Anniversary Edition Of SciFri Trivia We’re celebrating our 30th anniversary this week—and with 30 years of radio comes more than enough material for a round of trivia. SciFri Trivia extraordinaire and host Diana Montano quizzes Ira on how well he remembers some of the stories he’s covered on SciFri during its last three decades. Want to join the fun? Diana hosts virtual SciFri Trivia every Wednesday at 8:30 p.m. ET / 5:30 p.m. PT on Youtube and you are invited! Play by yourself or with a group and, if you win, enjoy the honor of naming one of the many plants in the SciFri office—and more! 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. Later in the hour, a look at the disruptive technology of quantum computing. What it is, where it is now, and where it is going. But first, the Omicron variant has been detected in the U.S., the first case identified this week in California. Last week, South African researchers identified and then sequenced the variant. And since then, scientists all over the world went into overdrive, trying to understand this heavily mutated new strain, and I mean Omicron has 32 mutations in the

spike protein alone. More mutations don't necessarily mean it's more contagious than the Delta variant or more likely to evade the vaccine. We just need to give scientists enough time to figure it out. Join to me now to help us understand how scientists are compiling data on Omicron, both inside and outside of the lab, is Caitlin Jettelina, assistant professor in the University of Texas School of Public Health in Dallas. She's also the author of the newsletter, Your Local Epidemiologist. Thanks for being with us today. Welcome to Science Friday. Yeah, thanks for having me. I'm excited to be here. Well, now that we have seen cases in the U.S., wasn't it always inevitable that Omicron would arrive here? Fortunately, we are fast, but unfortunately,

still, once we identify a case or a variant, that means it's probably been circulating under our radar for a little while before. And we've seen that, you know, cases pop up in Europe before even the cases that were identified in South Africa. So we had a hunch. It was in the United States. It was just a matter of time of us finding that needle in a haystack. And what is it about Omicron that has you and other scientists on such high alert? Is it a matter of? Is it a matter of the number of those mutations? Well, certainly the number of mutations got our attention because there were a lot. There are a lot compared to, for example, Delta and specifically the mutations on the spike protein. So, for example, with Delta, we had nine changes on the spike protein.

With Omicron, we have 32. And we pay attention to the spike protein specifically because this is the virus is key into our cells. And if the virus changes this key or even finds a different key for a different door, we need to know about it and really pay attention to it and figure out if that change on the spike protein, one, increases transmissibility, two, has the ability to escape our vaccine or infection-induced immunity, and or three, increase the severity of disease. And, like hospitalization or death. Does it share any mutations with the Delta variant in terms of giving you a hint of how it might act?

Yeah. So, and this is what also kind of brought this onto our radar. So Amhercon actually has a number of mutations we've seen on other variants of concern, like Delta, like you said, but also alpha and gamma and beta. In fact, there's nine mutations out of those 32 that we've seen. seen on previous variants of concern. There's one in particular. It is called P6-8-1-R, if anyone wants to know, and it's a particular mutation called a fear in cleavage. And that was on Delta as well, which made it so much more transmissible, this one little change. Unfortunately,

with Omicron, it has this fear on cleavage, as well as a second fear on cleavage, as well as a second fear on cleavage. And so we're trying to figure out what the two together really means. The fact that it was first detected in South Africa doesn't necessarily mean it first appeared in South Africa, correct? Yeah, no. And it was actually first discovered in Botswana on November 11th. And then three days later discovered in South Africa. And we really owe it to the scientists in South Africa, for one, identifying it to telling the world. So, thousands of scientists could be working on this as quickly as possible, as well as being very transparent about what's happening on the ground,

really walking us through case growth, what they're seeing at the hospitals, et cetera. Let's talk about how likely it is that Omicron will evade the vaccine. What's your take on that? Or do we not know that yet? So we don't know that yet. We certainly have hypotheses. And really what's driving those hypotheses is that a lot of some of the changes on Omicron reflect the changes we saw in beta. And beta is one of the previous variants of concern that have escaped our vaccine protection the most. Now, I think it's really important to realize or. address that immunoscape isn't a binary event. It's not yes or no. We're not going to start from square one. It's really, immunoscape is really more like corrosion, like picking away at the sides of

our protection. So we hypothesize that this Omicron variant will have a negative impact on the level of protection we have, but not fully. We'll still have some protection against severe and disease and death, and that's what scientists right now are trying to figure out. And could it be less deadly than the variants we have now? It certainly could. You know, the variant changes and mutates randomly. And what all the virus wants to do is survive. And sometimes, you know, if you're as virus is killing off their hosts, it's not going to survive. And so there's this balance between severity as well as immune escape, so it can out,

you know, smart our vaccines, as well as a balance and trade-off with transmissibility. Again, I feel like I keep saying this, but we don't know yet the extent in which that will happen. Yeah. We like it when scientists say they don't know rather than faking it. Speaking of faking it, tests, the tests we take for, you know, discovering whether we have the virus or we had it before, will this new strain be picked up for the tests that are currently in our drugstores? So I'll start with PCR tests.

And we got actually some really great news from South Africa on this, that PCR tests can actually tell the lab whether it's Omicron or not. And this typically isn't the case. Usually we would have to, you know, get the swab of the PCR. That PCR goes to a special lab for genomic sequencing. It can take, you know, a few weeks to know which variant cause that infection. With Omicron, though, it has a really special signal. And we actually saw this before with Alpha.

And it has a special signal on the PCR directly. So when a PCR is positive, it lights up three channels typically. With Omicron, it lights up two channels, which will indicate, you know, it's Omicron versus Delta. And this is really amazing news because it means we can track the virus much easier and much quicker within the United States and then across the world. And that's PCR. And so then we also have rapid antigen tests at our corner pharmacies that we can buy over the counter. Those will not tell us what variant it is, but it's still. can detect Omicron. We got some confirmation from the drug companies that it does still work. And that's

because those rapid antigen tests test for something other than the spike protein that hasn't changed. And so that's also great news as well. Okay. Now, if someone was infected with the Delta variant, would that protect them against Omicron? Yeah, this is a really good question. And, An important one we're trying to answer, right? So because the United States was hit so hard and continues to be hit so hard with Delta, one great question is what does the infection-induced immunity? How does that protect against Omicron? And unfortunately, a day or two ago, the WHO came out with their briefing and said that they have preliminary evidence showing a high reinfection

rate among those with infection-induced immunity. So those that have gotten COVID-19 before, but don't have the vaccines. And that's a really important information because it will tell us, you know, it's been almost 90 days since our Delta wave or our main one. And that will tell us and help us predict how high the COVID-19 wave will be this winter once Omicron or if and when Omicron enters the scene. How do you piece together all of the information to get a complete picture about Omicron and where it stands with the other variants and the virus itself? Yeah, it's a little, it's hard for an individual to do.

I'm trying to keep track of it. But from a scientific perspective, we really need to marry two sources of data. and these sources of data kind of come from two different angles. One is we are running lab tests right now. We call these lab studies. And what they're doing is seeing how are antibodies attached given amacron's changes, and if so, how tightly do these antibodies attach? And to answer this, scientists actually have to develop or engineer it's called a pseudo-virus.

And so they take another virus and attach the omicron. spike protein to it and let it grow in a lab. And this is why we keep hearing, you know, we'll know in two weeks, we'll know in two weeks is that because it takes time for that to grow. But they essentially grow a virus that mimics Omicron. And once they have enough of this sample, on a petri dish, people's blood that had the vaccine, mix it with this pseudovirus and see how our antibodies respond. really on a micro level. So this is more like lab scientists. On the other end, we have to marry, I call it real world data,

and that's epidemiology of what's happening on the ground, what are we seeing with spread, how quickly is it spreading, what's happening at the hospitals, is it severe, is it not, what is the symptomology that people are showing? And that's really important because lab studies are very different than the real world, right? In the lab we have, it's temperature controlled, everything's sterile, we're on a petri dish. That doesn't necessarily always pan out to what happens in our environment with our genetics, etc. And so having those two pieces really gives us the quote unquote true perspective on what's happening out there.

Well, thank you for sharing your true perspective. on what's happening out there. Yeah, no, thanks for having me. Caitlin Gentilina, assistant professor in the University of Texas School of Public Health in Dallas. She's also the author of the newsletter, Your Local Epidemiologist. We have to take a break and will we come back?

Quantum Computing. What is it? And will it be a game changer? Hey, Ira here with an exciting message. Science Friday currently has a dollar-for-dollar donation match in effect. This means that any donation made through December 31st will be doubled, including yours. Now, I don't have to tell you that the need for Science Friday is stronger than ever.

So please, head over to ScienceFriday.com slash support to make a gift. We depend on the generosity of fans and listeners. Again, that's ScienceFriday.com slash support. And thanks. This is Science Friday. I'm Ira Flato. Lately, I've been thinking a lot about disruptive technologies. And by that, I mean new ways of doing things.

that if they pan out could dramatically change the way we work and live. And one of those things is quantum computing, a way of doing calculations not with the ones and zeros of electrons flowing through transistors and electronic chips, but by harnessing the strange physics of the quantum world. I've heard a lot about quantum computing, as I'm sure you have, but how does it work? Why should I care? I want to know. So I've asked an expert who lectures on the subject to come on the show, Dr. Doug Stone is Deputy Director of the Yale Quantum Institute, and Carl A. Morse Professor of Applied Physics at Yale University is also author of Einstein and the Quantum, one of my favorite books. Welcome back to Science Friday, Doug. It's great to be back, Ira. Nice to have you. As I say, you have lectured a lot about why should we care about quantum computing. In a nutshell, can you tell us why we should care?

Well, this is to me the most surprising thing in modern physics in 50 years. When I went into graduate school, there was no such thing. And all these other things like Higgs boson and gravitational waves, people already thinking about. But this idea of a quantum computer was completely out of left field. It promises to give us solutions to problems that are at the forefront of technology and health and understanding the environment and so on. It gives us access to a computing technology that has never existed and could be revolutionary if it all pans out. Okay, let's talk about some of the details. First, let's define terms. What exactly is quantum computing? So the important

thing about quantum computing is that the information is not stored in the forms of ones and zeros, which are electrical signals in a standard computer. But instead is stored in terms of some quantum object. It could be an atom or molecule, or often now we have artificial atoms, nanostructures that behave like atoms and behave in a quantum way. And the most important thing is the information is stored not as a one or a zero,

but is what we call a superposition of a one and or zero, something that could, depending on each measurement, be a zero or a one, but actually also has additional information to specify what its state is. Sounds a little bit like Schrodinger's cat. Yes. And I would say the most exciting and surprising thing in this whole area is that having things be uncertain, you would think would be just bad for a computer. Why do you want to start with bits that are actually unstable and might be zero or one? It's hard enough without that, you would think. And the surprising discovery of mathematicians, theoretical physicist,

is that actually that can be harnessed to do essentially enormously parallel processing, and that allows you to do things that conventional computers will never be able to do. I mentioned your book about Einstein in my introduction, and I know that you have written a lot about Einstein and the ideas of entanglement, how key is that to understanding quantum computing? It's very key to understanding it, which is somewhat unfortunate because it's a very subtle and difficult concept, but it has been proven that a quantum computer will not have a advantage over a conventional computer if you don't use entanglement, which is a property of quantum states.

And it's a subtle property, but let me try to explain it. So imagine I have two coins, heads and tails. We'll call them magic coins. And they have the property that each one independently is a fair coin, half heads, half tails, randomly when you toss it. But when you toss them both, if one is heads, the other is also heads, or if one is tails, the other is also tails. They're perfectly correlated.

And so you might think that's not very valuable, okay, because I still have these random coins. I don't know if they're going to be heads or tails. But it turns out you do know something. What you know is you'll never have heads tails or tails heads. And therefore, there is information stored in the entanglement, which can then be exploited and processed. Interesting. If you were to point me to a box and say, there, over there is my quantum computer, and I opened up the box. What would I see inside that box?

Well, that's a great question. And stepping back a little bit, nobody in 1990, almost nobody, thought that a quantum computer would be useful in any disruptive way, maybe just as a curiosity. And therefore, no one had seriously said, what's the best way to do this? And so once it became clear from the mathematical analysis that it could be enormously useful. Then people start to say, what's the best way to build it? It was completely open. So there are designs where the quantum bits are molecules or atoms or ions. And there are designs where the quantum bits are photons. And then there are designs where the quantum bits are

sort of electronic excitations, more like a conventional computer. And the latter is the one, maybe I'll tell you about because it's the one we do here at Yale and we've pioneered. And that's where you have microwave circuits fed in with cables. So the cables would look almost like your cable TV. But then they go into a big can, which is incredibly insulated and then cooled down almost to absolute zero so that the circuits will behave like quantum objects and not like your light switch. And you can actually use them to store quantum states in your. conventional computer, your one and your zero is a voltage. It's not fluctuating much. It's a definite

value. Your quantum computer, your qubit, whatever it is, whether it's a microwave circuit, a superinducing circuit, or an ion, is in this uncertain state. And any interaction with the environment will tend to measure it and make it fall into a definite state. And then you lose the whole quantumness that allows you to do these unprecedented computations. What are the properties of the quantum state and the qubits that make the computer a quantum computer so much more powerful. And you talk about how much more powerful a quantum computer is than, say, an Intel-based processor. It's a tricky thing to quantify because it's not that it runs fast.

It just runs on different principles. It might run slow or at same speed as an Intel processor, but it's doing things in a quantum parallel way that no Intel processor can do. So the example I'll use is to think about storing ones and zeros in a memory, in a register, in a memory. Let's just choose 300 bits, not the billions in your computer. Okay, 300 bits is 2 to the 300 or 10 to the 91. That's a trillion, trillion, trillion, trillion, trillion, trillion, maybe.

if I said that the right number of times, states, even with 300 bits, right? So if you go through and try to create all the different states of one and zero in your memory, it would take you longer than the age of the universe to even store all the different states or process through them. Not that you want to do that necessarily, but it's an indication of the limitation. Now, with a quantum computer, I just need 300 steps, if there's a, 300 bits to create all the different possible states. I won't go into the details of how. That's 300 steps that I can do in a microsecond. So in a millisecond, I can do something that you could never do on a conventional computer in the age of the universe. Wow, that really is fast.

Do you see quantum computers in general use, or would one be purposely built for a specific problem? Definitely the latter, for two reasons. First, quantum computers are not actually for handling big data. It's really for computing things that are too difficult to compute with conventional computers. Maybe couldn't be computed in the age of the universe, as I was just saying. So where you have a big, tough compute problem, you would have a special purpose cloud quantum computer, and it would do that for you and it would solve that part of the problem. But the big data storage or just the everyday types of things you can already do well with conventional technology will not be replaced.

problem are you talking about then for a typical problem? So one kind of problem is the rooting problem. If you have to go to a hundred different locations, you know, in some order, and you have to figure out the most efficient way of doing that, that turns out to be a very, very hard problem. It's called the traveling salesman problem. And it's very hard to solve on a conventional computer. This is exactly the kind of problem you would want to solve for routing on a network. And that may be why Google is so interested in quantum computing. Interesting. Some technologists are saying that if and when we get quantum computers, that will be the end of e-commerce over the internet as your encrypted passwords could all be broken by someone listening in and possessing a quantum computer. Is that a valid

concern? Well, I would say not because I think people are developing quantum secure technologies, and we have no general proof that quantum computers can solve all the different encoding schemes that work pretty well on the internet. But it's interesting you mentioned that, because the thing that kind of just turned everybody sideways and created this sort of mad rush to quantum computing was the mathematical proof that one of the main. forms of encryption, the RSA encryption, which is used for securely accessing your credit card on the internet, that could be broken by a high-end well-functioning quantum computer, which we do not have yet. But that was how the sort of gold rush started in 1994 when that was proven.

And there's this other interesting kind of duality to it, which is that we can prove that with quantum channels, you can have unbreakable. codes. So if you're willing to switch to all quantum channels, they're actually, you would be completely quantum secure. Do we have to redo the whole internet for that? Or could those? That would be very hard. I agree. You'd have to redo a lot. But if you had specific channels that you wanted to make hyper secure, you know, we already have technology to do that. It's not released. Who's doing it? But some banks have expressed interest. The government certainly has expressed interest. There may already be a quantum secure channel from the Pentagon to the White House we just don't know about.

So is that where the money is coming from in this field? I mean, who's spending money on this besides Yale? Well, Yale is not spending nearly as much as we would like. And it's, no, they're spending enough. But yeah, so certainly DOD. I mean, if you tell a general that you can break the other people's codes, they get excited, right? So the DOD is very excited. But now I think people are realizing that the big compute problems can be incredibly important for the information technology sector and also just for any kind of difficult problem in materials. In the end, all materials problems are doing a computation of a quantum problem with a classical computer. And it's been shown that for many problems, quantum computer can be much faster for that. So now just to do chemistry or material science or medical imaging or something, this might eventually be useful.

A great example that I learned about is this so-called fixing of nitrogen. So ammonia is an incredibly valuable chemical. It is, I read, it's a precursor in 45% of the world's food between fertilizer and other ways in which ammonia comes into. food. And then, of course, there's also explosives and other things you can make with ammonia. So we have a process that's over 100 years old for doing it called the Haberbosch process, which takes a lot of energy. It takes like 2% of the world's energy to use to make all this ammonia that we need. And it admits 3% of our carbon, all our carbon. Amazing. Wow. Well, it turns out that there's a nitrogenase, which is a biomolecule enzyme that can just interact with air and produce

ammonia for plants. It's called Fomoco. I don't know that much more about it, but we have no idea how it works. It's a big molecule. It's a complicated thing. It's beyond our current scientific understanding. That's the kind of problem that you could imagine a quantum computer could simulate, we could go in and pull it apart with a quantum computer, understand. And the point is that this biomolecule is doing it at room temperature, whereas all this energy comes from having to heat up the ammonia and the Haberbosch process to 450 degrees centigrade, put it at high pressure, et cetera. That's why it takes so much energy. If we could just do it at room temperature and pressure, we would save these huge quantities of energy, carbon emission, etc. This is Science Friday

from WNYC Studios. You know, you've said we don't have a functioning quantum computer yet. What's limiting this from being a transformative thing? Is it the technology, the understanding, the cost, what will limit the impact here? And when do you think we'll have a functioning quantum computer? So it's certainly got much more realistic in the last five years that we'll have something. I mean, right now, six or seven companies, including IBM and Microsoft, they'll let you play on their quantum cloud, even though they're,

they're not doing anything really important with it yet because the computers aren't good enough. But it's really gotten much closer to being realistic. So what's making it quite difficult is what I said before, then making such a fragile system robust and being able to make it do this very specific computational task that you want, it's never been attempted before in the history of man. I mean, there's nothing comparable in any of our physics that's as making a, say, a thousand-quibet quantum computer. So everything is being pioneered. We don't even know which technology is best. And people are making progress, but I think it's somewhere in between physics and engineering that we're stuck.

Do you think this is a technology that will all have equal access to, or will the world be divided into quantum halves and quantum have not? Well, I do believe that all of these companies will provide quantum cloud services if everything pans out. So if you have money, even if you're not in America, you'll have access. Now, initially, I wouldn't be surprised if defense departments were trying to keep somethings classified and so on. on. We know that two-thirds of the money being spent on quantum computing has actually been sent by China. So China is really interested in this, and I don't know what they're going to do if they get it. But anyway, I think it's going to be expensive. I don't know if it will ever come down so that, you know, you could use that just, you know, with your cell phone going to ask something from the

quantum cloud. I do not know if that will ever happen. Doug, we have run out of time so much to talk about so little time. Thank you for being with us today. Well, thank you. Very interesting stuff. Dr. Doug Stone is deputy director of the Yale Quantum Institute and Carl A. Moore's Professor of Applied Physics at Yale University. You might want to check out his YouTube lecture and why we should care about quantum computing.

It's got a lot of good extra stuff in there. We're going to take a break and let me come back. News about tiny living robots called xenobots. We first told you about them about two years ago. but now they can replicate. Yes, stay with us. This is Science Friday. I'm Ira Flato.

About two years ago, we told you about an experimental living robot, a robot fashioned out of cells from a frog embryo. The shapes of the robot were designed by a computer, and then a skilled microsurgeon crafted the robots out of two kinds of frog embryo cells, skin cells which were mainly for structure, and heart cells which can,

contract. They found that the living robots, which they called xenobots, could move around on their own and potentially perform useful work. Well, fast forward to this week and a new generation of xenobots, robots that can now reproduce. Joshua Bondgard is a professor in the Department of Computer Science at the University of Vermont and one of a team of researchers who published this work in the proceedings of the National Academy of Sciences. Welcome back to Science Friday. Thanks for having me back on, Ira. So you've been busy since two years ago, when we spoke at, these little cell things that looked like Pac-Man are kind of wiggled around in a dish.

How did you get from that to self-reproduction? Yeah, it's a great question. So when I was here two years ago, I introduced you on behalf of our team to the xenobots. At that time, they walked along the bottom of the dish using heart muscle cells. In March of this year, we published a second paper where we showed that xenobots could swim. They grow small hairs called cilia on their surfaces, and that allows them to move through the water in the Petri dish faster than our walking bots. In that second experiment, we sprinkled some very small pellets into the dish as well, and we put a swarm

of xenobots together to see what they would do. They ended up moving around like very small bulldozers, and as a result of their action, they pushed these pellets into small piles. At that point, our team asked each other, what would happen if we replaced those pellets with more skin cells? So now we sprinkled the dish with frog skin cells loose in the dish. We put nine xenobots back in the dish. They pushed those cells into piles. And after five days, those piles began moving.

And thus were born child xenobots. Whoa. How did that happen? What did they do? What went on in that dish? Yeah. So what happened is when some of these frog cells were pushed into piles, if there were enough of them, if there was on average about more than 50 cells in a pile, they would

gradually adhere to one another. Cells tend to be sticky under certain circumstances. So the pile would sort of become welded together. And the cells would talk to one another, what language they're using. We don't know that's something our group and others are trying to figure out. But whatever those cells were saying to one another, they agreed to grow cilia, these small hairs on their surfaces. And if that pile was large enough and had enough cilia, the pile would start to move. So they didn't really split apart and reproduce that way.

They reproduced with the new stuff that you put in there. That's right. So we refer to this technically as kinematic self-replication, which is a bit of a mouthful. The kinematic means that they make offspring by moving. They act like bulldozers, make piles, and those piles start moving. And we've referred to this as replication rather than reproduction. Replication is sort of the umbrella term for anyone or anything that makes copies of itself. So this is a form of replication, not the usual reproductive form of propagating oneself.

You see in nature like trees that grow seeds or mammals that grow babies inside themselves. Do they look and behave like the original Zinobots? They look a little bit like them. You referred to the Pac-Man shape of these. In the second part of the paper, we actually asked an AI to design Xenobots that would be more replicative. And what I mean by that is the AI dreamed up a particular shape, which ended up being this Pac-Man shape. And if you put nine of these Pac-Men in the Petri dish, they push more cells in their mouths. and end up making larger piles.

Those larger piles mature into larger children, which end up pushing more cells and making grandchildren, great-grandchildren, and great-great-grandchildren. Now, is this assembly process deliberate or is it just random chance that they make these clumps? As scientists, we need to be skeptical, so our assumption is that it's just random action.

So although we somewhat tongue-in-cheek refer to these xenobots as bots or robots. They're acting more like mechanical wind-up toys. They just move through the dish and happen to push cells into piles. That being said, cells themselves are incredibly complex and smart machines.

So there may be some agency going on in these swarms of replicating xenobots, but we haven't investigated that yet. You originally were using frog skin cells and heart cells. And of course, these don't have cilia. Do you have a reason to explain how they developed cilia later on? Yeah, this is one of the surprising pieces of this study in the previous one. There are certain conditions under which the xenobots will grow cilia.

In the normal frog, the frog grows cilia on its skin and uses that to sort of brush material and particulate matter off its body. Here we're kind of causing the xenobots to adapt the use of cilia for something else, which in this case is propulsion. Are there parts of them that are original frogs eggs and could mature into frogs? So in all of the xenobot work we've done so far, this is all genetically unmodified material. If you break open the cell and read out the DNA, the DNA is indistinguishable from normal frog. One of the interesting findings of this from a scientific perspective is that apparently frog DNA doesn't encode just frog.

under just the right environmental conditions, like the ones we've set up here, they can mature into very different stable forms and function that are very far from normal frog. Are you saying you can get some weird kind of creature instead of a frog that would come out of this? Yes, absolutely. That's what we're saying. The xenobots look and act completely different from normal frogs. They're millimeter-sized, and they push cells to make copies of themselves. This is not something that normal frog does. So this is actually a continuing story unfolding in Mike Levin's lab.

Mike Levin is my biology colleague on this project. And the Levin Lab has done a lot of important work on sort of rethinking through what DNA actually does. It doesn't strictly encode organisms. It encodes something else. Something else. So to unpack that idea a little bit more, DNA, somehow directs how cells organize themselves in response to certain environmental conditions. A frog cell under normal froggy conditions will develop into a frog. But if you rearrange some of that

material, if you liberate cells from the normal embryo and put them in very strange alien surroundings or an environment, they didn't experience normally, they develop into something else. And if that's something else were to get out into the wild, back into a pond, let's say, could they continue to develop? That's a great question. So we're dealing with self-replicating systems here. We have to be very careful. There are a lot of animal welfare rules in force here.

We're very careful about lab safety. This is not something that's going to escape from the lab and grow out of control. If we simply don't make dissociated loose frog skin cells of air, to these xenobots, they stop replicating. Now, I understand that since this was published, you've heard lots of questions about why, why do this, whether this was something that you should do? How do you answer that?

That's a great question. For very good reasons, we understand that a lot of people are apprehensive, particularly at the moment about small biological things that replicate out of control. And that's part of the rationale behind this work. We as a society do not understand how to control things that replicate. We would like to slow the spread of bad things like COVID, and we would like to learn how to spread useful things like vaccines to those who want it faster. We're not very good at accelerating or suppressing replicating systems.

Where do you go from here? What's the next step in your process with these xenobots? One thing we'd like to do is automate the fabrication of xenobots. We'd like to create biofabrication facilities that can print out or make the billions of designs that our AI has already come up with. We're also looking at building biobots out of other cell types taken from other organisms. There's no reason we need to stay with frogs. It may become possible in the not too distant future that we could create biobots out of human cells and start to explore potential medical applications.

No push back from there, I imagine. I would imagine. Thank you very much, Joshua for taking time to be with us today. Of course, it was my pleasure. Joshua Bondgard, professor in the Department of Computer Science at the University of Vermont. As you listeners may know, here at Science Friday, we're a bunch of nerds. Yeah, and I mean that in the best way. It's a badge of honor around here.

And what the nerds like to do? Trivia. Yes. So let's do some right now. One of our resident trivia nerd, sci-fri-producer Kathleen Davis joins us. Hi, Kathleen. Hey, Ira, you are completely right. I am a big old trivia nerd. As we all are around here. The thing is, though, I love to play trivia, but I am not very good at it. So it's kind of a love-hate relationship. You know, I have someone who can help you. Seriously. One of my favorite trivia events is Science Friday trivia, which has a love-hate relationship. happens every Wednesday night on SciFRI's YouTube channel. And in celebration of our 30th anniversary year, resident sci-fi trivia host Diana Montano has suggested we give our brains a test run before next week's trivia night.

And I always listen to Diana's suggestions. So welcome Diana. Hey, Ira. Hey, Kathleen. It is great to be here with you both. Science Friday trivia is so much fun, not to do my own heart, of course. I am inclined to agree even when I get a big old goose. It's all right. I'm also a trivia host, but not great at trivia, Kathleen, so we're in the same boat.

Well, we've done science, movie trivia, charismatic creature trivia, outer space trivia, you name it. We even test our fans' listening skills. Round three, almost every game is last week on SciFri. So if you listen to the show, you have a leg up on those questions. It's a whole lot of fun, and Wednesday has become my second favorite day of the week, after Fridays, of course. I've got some trivia questions prepared for you this week, Ira and Kathleen, that are all about a favorite winter pastime of hours here at Science Friday, birds and birding. Are you ready to go?

Well, what do you say, Kathleen? You're ready to help me out a bit here because... Well, I was going to say you are here to help me, but I guess we'll see how we do. This is Science Friday from WNYC Studios. In case you just joined us, we're playing Science Friday trivia with our trivia host with the most, Diana Montana and sci-fi producer Kathleen Davis.

All right, let's do this. Unlike most birds, the male club-winged mannequins of Ecuador have evolved solid wing bones. That makes it harder to fly, but easier to do what. A, make a buzzing sound to attract female mannequins. Forage in the dirt for seeds. C, fight other male club-winged mannequins. Or, D, use its wing to crack open other birds' eggs. So again, it's got solid wing bones.

Does it make a sound? Forage for seeds. Fight other birds or open bird eggs with those wings. There's no E selection on this one. All of the above. None of the above. Well, I... It's one of those, I promise.

Of course I remember that, Kathleen, don't you? Absolutely. Oh, yeah. You want to help me off? What have you got? Yeah. Well, I was going to say that... maybe because they don't have the hollow bones, which help birds fly, and maybe that means that

they stay on the ground? I thought the answer would have been, which is not one of the options, that they can glide better with their wings locked like that. But I'll go with your gut on this one. Yeah, I'm going to say, I'm pretty sure that it would be so that they can be heavier and stay closer to the ground. So, Ira, if you want to come with me, I'm going to say that that foraging, B, is the right answer. All right. Your final answer was B, foraging in dirt for seeds. And unfortunately, I've stumped you both with this one. It's actually A, making a buzzing sound to attract female birds. That's right. So they still can fly. They don't fly quite as well as some other birds, but they swing their wings behind their heads

at a rate of about 107 times per second and beat them together to actually create a buzzing sound. Wow. And it sounds, it's like a little like high-pitched sound. It's like, bus-biz, that's what it sounds like. It's amazing. Want to do that again? No.

I did write this question so I could do that, yeah. All right. Well, let's move on after this wreckage. Yeah, not our best work. All right, you've got another chance to redeem yourself. So you're ready for question to? Yes, let's do it. No, but ask it anyhow.

Go ahead. All right, here it comes. So last year's pandemic shutdown shifted the way many of us worked, including white-crowned sparrows in San Francisco. Research published in October 2020 showed that sparrows behaviors changed in what specific way. A, they flew lower throughout the city. B, they sang in lower. registers. C, they went to bed earlier, or D, they laid more eggs. I think I actually know this one

because I remember reading about this during the pandemic. I am pretty, pretty sure, Ira, that it is that they sang in a different register. Yeah, yeah, yeah. I was going to say that also. Okay. I think we should go with B. I'm afraid of the answer. Well, you have, you've come out with one point because that is the correct answer. Yeah. Yay. Yeah. Woo. Great job, you two. Thank you, Diana. You're being very nice. So in 2012, these researchers actually found that they slowly pitched their songs to a higher register to be heard over city noise. So they just really in 2020 shifted their songs back down when people stopped commuting and moving throughout the city because they could be heard again. So they just kind of went back to their regular singing, which one day we all probably will too.

Yeah, not me. You don't want to hear it. Okay, Diana, give it to us straight. How did we do? Yeah, yeah. What is our score, Diana? You got one out of two, and I'm, I've got to say that's a pretty great score. So congratulations to you, too. You're welcome any time at our free Science Friday trivia. It's really fun. So I hope you will team up and come to a future trivia. I would love to. Our team will not do very well, but, yeah, well, absolutely. Thanks for dropping by, Diana. It's always fun to talk trivia with you. And where can our

listeners learn more and see if they can beat our record, which is not really hard to do, I don't think. Tell them. Well, it is always a pleasure to try and stump you both. If you want to join us for our weekly trivia nights every Wednesday evening at 8.30 p.m. Eastern or hear about our special themed trivia nights coming up. You can sign up on our website, ScienceFriiday.com slash trivia. That's sciencefriiday.com slash trivia. Thanks, Diana.

Yeah, thanks, Ira. Thanks, Kathleen. And thanks to SciFair producer and just OK trivia player, Kathleen Davis. Thank you, Ira. I will wear that name like a badge of honor. We have run out of time for this hour. If you missed any part of the program or you would like to hear it again, yeah, subscribe to our podcasts or ask your smart speaker to play Science Friday. Of course, you can say hi to us all week on social media, Facebook, Twitter, Instagram, or email us the old-fashioned way, SciFri at Science Friday.com. feedback, tell us what you'd like us to cover. Have a great weekend. We'll see you next week. I'm Ira Flato.