Science Friday - History Of Sex, Plastic Battery, Mosquito Smell, Postpartum Art. June 3, 2022, Part 1

Episode Date: June 3, 2022

Scientists Found The Biggest Known Plant On Earth This week, an underwater seagrass meadow claimed the title for the world’s largest plant. This organism sprawls across 77 square miles of shallow ocean and has survived 4,500 years. To accomplish this, it kept cloning itself and created identical offshoots to spread along the sand. The ocean has changed wildly over the last 4,500 years, yet this plant has survived. Researchers believe that cloning itself may have helped the plant adapt to a changing ocean, offering hope that seagrass meadows may be more resilient than expected in the face of climate change. Sophie Bushwick, a technology editor at Scientific American, joins Ira to talk about how this mighty meadow persisted for millennia and what it tells scientists about climate change. Sophie and Ira also discuss other stories from this week in science, including what countries are most responsible for fueling the extinction of wildlife, what a well-preserved fossil tell us about the sex lives of ancient trilobites, why male mice are terrified of bananas, the creation of a flea-sized robot that walks like a crab, and how scientists developed an algorithm to pinpoint the whereabouts of unknown asteroids.   Building A Better Battery… Using Plastic? The lithium-ion battery in your cell phone, laptop, or electric car is a crucial component of the modern world. These batteries can charge quickly, and pack a lot of power into a small space. But they’re also expensive, require mining scarce lithium, and need to be handled carefully. Other battery technologies have issues as well. For example, the heavy lead-acid battery that starts your car is quite reliable—but lead has its own environmental and health costs. That’s why PolyJoule, a startup company based near Boston, is trying to create a new kind of battery, somewhere on the performance curve between those old lead-acid batteries and lithium-ion cells. Their technology relies not on a metal, but on polymer plastics. Read more at sciencefriday.com.   Bug Off: Why Mosquitoes Have An Annoyingly Amazing Sense Of Smell Mosquitoes use their sense of smell to find their next meal: us. So what would happen if you tweaked their smell so that humans smell really gross to them? That’s what Dr. Chris Potter and his lab recently tried to do—they changed the neurons responsible for the insect’s smell detection, so that in the presence of animal odors, their olfactory systems would be overwhelmed. Instead of smelling like a nice meal, mosquitoes would be repelled by the scent of humans, like if you were stuck in a small room with someone wearing too much cologne. This method worked in Drosophila, the common fruit fly, so Potter and his team were hopeful that would also be the case for mosquitoes. Instead, the experiment didn’t go as planned. Because finding a blood meal is so important for mosquitoes, those little buggers evolved backups for their backup receptors. When Potter turned one pathway off, another one kicked in. Ira talks with Dr. Chris Potter, an associate professor of neuroscience in the Johns Hopkins University School of Medicine, based in Baltimore, Maryland, about his findings, and why we can never quite get mosquitoes to bug off.   So You Think You Know About Sex When it comes to sex, there’s really no such thing as normal. What was once considered taboo, sometimes goes mainstream. And some things considered new have been around as long as sex itself, like birth control, abortion, and sexually transmitted infections. All that and more is contained in the new book, Been There, Done That: A Rousing History of Sex, by Rachel Feltman, executive editor of Popular Science, based in New York City. Radio producer Shoshannah Buxbaum talks with author Rachel Feltman about queer animals, crocodile dung contraception, ancient STIs, what led to the United States’ original abortion ban, and more.   Processing Postpartum With AI And Synthetic Breast Milk Art One of Ani Liu’s strengths as an artist is her ability to process emotion through different scientific mediums: machine learning, chemistry, 3D-printing. The result is often visceral: she’s used organic chemistry to concoct perfumes that smell like people emotionally close to her and engineered a device that enables the wearer to control the direction of swimming sperm with their mind. And at her new exhibition—next to a 3D-printed sculpture of a pig’s uterus—lies 328 feet of clear tubing with a milky-white substance pumped through it, a commentary on pumping breast milk as a new parent. “I wanted to use my own breast milk, but it wouldn’t be stable for the duration of the show,” she said. Liu became a parent shortly before the pandemic, and she channeled that experience into a new show called “Ecologies of Care,” to process her postpartum period and the communities in her life that helped her through that time. “I hope that this can allow new parents to bond and maybe feel less lonely,” she said. “In making it, I was questioning how do we create better communities of care? I made all of this work before the formula shortage, before our reproductive rights were even more under threat. When I look at this, I’m hoping that you see this particular slice of love and labor.”   Transcripts for each segment will be available the week after the show airs on sciencefriday.com.   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, we'll talk about plastic batteries, why mosquitoes are so annoying, and the weird and wonderful history of sex. Yes. But first, some exciting news in science this week. Scientists recently crowned an underwater meadow of seagrass as the world's largest plant, beating out a colony of aspen trees that once held the title. Joining me now to talk about this discovery and other science stories of the week is Sophie Bushwick, Technology Editor at Scientific American, based in New York. Welcome back, Sophie. Thank you.

Nice to have you. Okay, so science has just discovered the largest known plant on Earth. Tell us about that. So this is a plant that covers an area about 77 square miles. That's a plant the size of Cincinnati. It's a particular kind of seagrass called Poseidon's ribbonweed, and there's lots of meadows of this off the coast of Australia. So researchers were studying the genetics of it and they took samples from all these different meadows. And what they found was many of these samples were genetically identical, which suggests they are all clones of the same seagrass and that it has been growing in this area for about 4,500 years.

Wow. Wow. It's lasted millennia. How has it lasted this long with, you know, changing climate, other woes? Well, they think that one of the keys to its survival might be the fact that it has two sets of chromosomes, which is something. called polyploidy. Now, this is not good in animals, but in plants, it apparently has lent this particular plant some resilience to changes in climate, but it has also made it impossible for it to reproduce sexually. So that's the reason it's cloning itself and making all these genetically identical versions is because that's the only way it can reproduce. I'm reminded of the humongous fungus that used to hold the record for the largest living organism, I think. Yes. I mean, and that's also kind of contentious, right? Like, what counts as the largest organism? So you could argue that

the Aspen Grove, you mentioned, is still the largest individual plant because its root system is all connected. But this would be the largest plant overall. And then there's the question of, like, are we talking about the area of surface it covers? Because this covers a much greater footprint in area than the aspens do. But does it weigh as much? So there's all these different criteria when it comes to it to the official largest plant, but this one definitely covers a super, super impressive area of the ocean. All right. Let's pivot to the animal kingdom right now. There's been some new research on what countries are most responsible for the rise in animal extinctions. What did this study look at? So this study was looking at how consumption and global trade creates this demand for resources

and how often the place where these resources are consumed is inadvertently affecting areas, you know, thousands of miles away. So for an example, you can look at the Western lowland gorilla, which is this very endangered species. Its population is expected to plummet by about 80% over the next 65 years. And it lives in Cameroon and neighboring countries. But the reason it's endangered is because of raw materials being extracted from its habitat. And those raw materials aren't being consumed in Cameroon. They're being shipped away to other countries. They're being shipped to China where they're made into products that are then sold in the U.S.

So in that way, the U.S. is driving this extinction, even though consumers in the U.S. might not be aware of it at all. So what these researchers wanted to do is, like, say, which countries are driving extinction in other areas, which countries are suffering from biodiversity losses due to consumption patterns in other countries? and then which countries are in a situation where it's their own domestic consumption that's driving domestic loss of biodiversity. And what they found is there's a group of 76 countries they call importers, which are importing products and thus driving the decline of endangered species abroad. And the U.S. is a big one in this category. Other members include Japan and France and the U.K. And then there's a smaller group of countries of only about 16 that researchers classify as experts. So they're exporting products, which is causing biodiversity loss and endangering species there.

And that's only about 16 countries. And then there's 96 countries where it's domestic consumption. That's the problem that's driving extinction risk inside those countries. Let's turn to another ancient organism. The animal called a trilobite. Some interesting news about trilobite fossils here? Yes. some trilobite naughty bits have been exposed by this 508 million-year-old fossil.

So this is the first known male appendage sex organ from trilobites. And it's not a penis. It's something called a clasper, which is a part that certain marine species used during mating. The male will have this and it'll use it to hold the female nearby so it can release sperm and be more confident that they will fertilize the female's eggs. But it's really hard to find these parts because any soft parts, it's hard for them to survive. And trilobite fossils, they're some of the earliest hard-bodied animals. And there's a ton of them in the fossil record because of those hard bodies.

But their soft bits aren't preserved. Researchers have to kind of extrapolate that they exist based on maybe spots in the shell where they think a leg attached. But this particular fossil was fossilized on its side. And so a lot of its appendages were preserved, including these claspers. Wow, that is an interesting sex act that they do there. Yeah, a lot of modern animals also do it. You know, sharks, shrimp, horseshoe crabs, many of these species have claspers. But the other thing is that this is a particular trilobite species.

There's about 20,000 trilobite species that we know of. So it's possible that some of them didn't have this organ. Interesting, interesting. And we'll be talking more about the secrets of animal sex lives a little bit later in the program, not trilobites. But there's even more weird animal news this one. week, such as why mice are afraid of bananas? I had no idea, Sophie. Neither did I. Yes, so researchers were looking at some male mice and how they behaved around pregnant and lactating female mice, and they found out that these mice were getting incredibly stressed

out, and they traced it to one particular chemical compound called N-pental acetate that was in the urine of these females. And it just so happens that that compound makes bananas smell like bananas. So the researchers had already tested how the males behaved when they were exposed to this urine. So now what they did was they bought some banana oil and put the males in a cage with it. And sure enough, the male stress response spiked. They started releasing this chemical that indicates that they were upset and scared. And it was all because of that banana smell. And so what does this discovery tell us about animal communication? Well, one thing that male mice tend to do is eat mouse babies.

So this is something that they might do. If there's a female with babies, she might be less likely to mate with them and get pregnant. So they will eat or otherwise kill these babies and then mate with the female. So the females have evolved this defense mechanism, which is that when they're pregnant or they're lactating, they will release this chemical. and that freaks out the males and tries to drive them in an effort to drive them away. Can we use this new knowledge? I mean, I think I'm thinking of the pesky mice that live in my basement, maybe some sort of mouse repellent with this idea. Yeah, my first instinct was like, I got to go buy bananas and put them all around my apartment.

But the problem is it's not clear whether female mice are quite as scared of it. So you might end up providing, you know, some fruit salad for female mice and actually attracting them when you're trying to drive away the male mice. So I don't think that this is ready for prime time yet, but it is an intriguing direction that maybe researchers could keep exploring. Cool. Cool. Next up is a tech story. Scientists built a tiny robotic crab, but this is a really tiny crab, right? It's about the size of a flea. Wow. And it's really cool because the way it moves is it's made of this material called a shape memory alloy. basically it'll change its configuration from its original shape to a different one based on how hot it is. And the researchers use the laser to heat different parts of the body from a distance.

And as it gets hotter and then colder, it's confirmation changes and that makes it move. It can skitter sideways in a motion that's very similar to the way a crab sidles back and forth. And in fact, that's the reason this team chose to develop it in the crab shape because its motion reminded them of it. But, I mean, it can also twist up its legs. It can crawl. It can even jump based on how they hit it with this laser. Wow. So what would be a good use for something this tiny? So you can imagine a tiny robot like this maneuvering in a very confined small space. Possibly it could be used someday in the future for some sort of surgical procedures. Maybe it could be used to assemble very tiny, delicate machinery as well.

You know, I'm wondering, okay, let's say you use this in the body. I'm thinking of the old movie Fantastic Voyage. You have to Google that. So what happens if it's in your body? How do you get rid of it? They would have to think about that, I would imagine. Yeah, I think they would definitely have to consider that this is more of like a prototype proof of concept device. I definitely would not want one of these in my body at this stage in its development.

But I think the idea is eventually it would be manipulated into the body and then manipulated back out. Are researchers looking for other critters to base robots off of? Oh, all the time. Like even just this particular research team, they've also developed little robots that look like other insects like beetles and inchworms. This does seem like a fruitful technology to move forward with. Yeah, another really cool thing about it, it's manufactured in two dimensions. So it's cut out is like a flat shape. But it's made of this sort of springing material that pulls on the 2D shape and springs it into a 3D one after it's been cut out. Okay, we've got time for one more story. And this one takes us to spin it. where scientists have a new way to study outer space from home, right?

Tell us about that. Yes, this is really cool because it repurposes existing data and information. So it is basically an algorithm that lets researchers hunt for asteroids without having to look through a telescope or even launch a specific new asteroid telescope. All they have to do is apply this algorithm to existing images and data from, that have already been gathered. And it picks out spots of light that might be asteroids. And then if those are confirmed, it can start calculating the orbit of those asteroids and maybe say, hey, is this thing going to be coming close to Earth? Is this a potential threat? Have they discovered any

asteroids out there yet? Yes. They looked at a set of data from one lab for a limited time period of just several years. And they found more than 100 asteroids in that data. And they have a threat to our planet. As far as I know, you don't need to keep an eye on the sky just yet. They don't seem to be imminent threats to us. But this is just a really intriguing option for looking for asteroids. So NASA says that they've already discovered about 30,000 near-Earth asteroids. So 100 isn't a super large amount compared to that. But that's just what they got from one set of data. So it's really exciting to think of what they'll find when they start applying this more widely. I'm sure asteroid nerds are jumping up and down.

Because, you know, it's low maintenance, right? You don't have to spend a lot of money and build telescopes and do things like that. Exactly. It's high reward for low cost. Well, thank you very much, Sophie. Always good to have you back. Thank you. Sophie Bushwick, Technology Editor at Scientific American based in New York.

We're going to take a break, and when we come back, could building a better battery, perhaps one out of plastic, help smooth out our energy woes, Stay with us. We'll be right back after this short break. This is Science Friday. I am I. Refleto. That lithium ion battery in your cell phone, your laptop, your electric car is a key part of our modern world. Fast charging, compact size, high power, but it has downsides like costs, the need for careful handling and careful temperature control. Too cold and it doesn't work well, too hot, it can catch on fire. That lead acid battery that starts your car is also a relic of the past and not ideal for large-scale energy storage.

Well, a startup based in the Boston area is developing a battery, it says, might be able to replace those batteries with one that is not based on metals at all, but on a polymer, plastic, a plastic battery that may be a solution for storing electricity on a large scale from wind or solar power generation or even right in your home. Eli Pastor is CEO of Polly Jewel based in Belrica, Massachusetts. Welcome to Science Friday. Thank you so much. Great to be on the show. Nice to have you. All right, what does a plastic battery look like? A plastic battery looks more or less like a conventional battery.

It's got an anode, it's got a cathode, it has electrolyte, and it's encased in a typical battery form factor. The key difference is are what are the active materials that actually store charge? So architecturally, it doesn't differ from your traditional lithium ion battery, but inside is where the magic happens. Let's talk about that magic. What is inside? Well, polyjule takes a bit of a contrarian approach to lithium ion or energy storage in general. We say technology has been out there for decades, and it's solved a whole bunch of problems. And when we look at grid level energy storage, it's not hitting the right metrics. So safety is a key component when you look at utility scale energy storage. You want to think about energy storage as a multi-decade asset that is going to sit unattended, like a transmission line or like a utility pole. So that means it has to be ultra-safe in wind, weather, temperatures, anything like that. The second is sustainability. Lead acid, as an example, is a great success story in terms of recycling, I believe 99% of, all lead acid batteries are recycled. And then the other side of it is that other 1% poisons

millions of children around the world per year. So if you have a battery chemistry that eventually is going to end up in landfills and leach into water supplies and soil supplies, you don't have a long-term solution. The last part is lifetime. People tend to still look at batteries as a consumable item. A lead acid battery will last three to five years. The best lithium ion batteries will last seven to ten years. A typical utility pole will last 30 years in a hydroelectric plan with minor modifications will last 50 years. So we like to think about energy storage as having to be in the classification, not of consumed batteries that can be discarded, but long-term capital assets that can add benefit to society. And so how does a plastic battery solve those problems?

There's a couple of different ways that it solves it. First is from a material supply standpoint. So on one side, if you think about plastics from a feedstock perspective, you're not dealing with mining. You're not dealing with copper and cobalt and lithium and all of the other ecological disruptions. You're dealing with a plastic supply chain that's been well established for half a century. The other side of it is if you think about a plastic from an environmental standpoint, there's two aspects which are great. Number one, it's recyclable, right? You can take a plastic, you can reform it, you can add it into new plastics, and you can reuse it. The other side of it is that a plastic, by its very nature, when it is desensitized, it's an inert material.

So a lot of the toxicity that comes from battery pollution actually comes from the metals that are in it. Not just lead as a metal, but lithium, cobalt, copper, nickel, all of those metals, whether they're in the parts per million or 10, of kilograms cause an environmental toxicity footprint. And by using plastics, basically at the end of life, you've got into the nerd material. You know, you hear stories about a lithium battery catching on fire or exploding if it somehow gets short-circuited or punctured. What happens to a plastic battery? Nothing happens, actually. So we actually, we short-circuit ourselves all the time and they recover 100%. Short-circuit, punctured with a nail, heat it up, throw the kitchen sink at it. It's still a very safe, ultra-safe battery.

Okay. There's got to be a downside to everything, right? So what's the weakness of plastic battery? Absolutely. What's the catch? The catch is we're five times less energy dense than a lithium ion system. So we're not going in mobile applications. We won't be going into cell phones anytime soon.

We won't be going into EVs. We're focused exclusively on grid-level stationary applications where volumetric energy density is not the key driver. The key driver is safety, sustainability, long lifetime, and cost. And so for cities looking to back up or store their electricity from their wind or solar generation, you have a lot of room. So you could put a lot of batteries of this size in there that are not as efficient as lithium. That's right. And think about this is where safety comes into it. So take one of the hardest cities to do business in New York City, right? And New York City obviously hates anything that is flammable anywhere. If you have an ultra-safe battery, you know, you can throw small units

in 10% of the population's empty cupboards and accomplish the same amount of energy as throwing a massive battery installation outside of New York. That safety enables you to either go with a distributed version or go with a centralized version in a cheaper piece of land where footprint is not an issue. So you're saying this battery would also work, for example, in my basement. enough room for this? Oh, absolutely. Think of it as, you know, for an equivalent single family household, it would be about the size of one and a half large refrigerators. That would give you a full day of backup. Okay. You mentioned the need for long life. How long does it last? And what happens then? You know, the honest answer is we're not really sure how long our batteries last. A year ago,

we said 12,000 cycles. This year, we're saying 20,000 cycles. But real world cycle life testing takes physical time. So it's quite possible that we're going to be at 30,000 cycles in a year from now. But from a capital and depreciation standpoint, we call a battery a two to three decade battery. And after that, the energy and power landscape is going to be different in 30 years from now. So it may be time for an upgrade. I would think so. If you can get it the last two to three decades, I think you've done pretty well. We hope so. So what's the time frame here? Are you still in testing phase? Would it be rolled out at any time? Do you have

customers? So there's multiple valleys of death for energy storage startups. You start with the cell chemistry. You move to a prototype. You have to get your first commercial customer. You have to scale up that prototype. Those are probably the first five valleys of death. Pollyjol passed those a year and a half ago. So we've produced 20,000 cells. We've integrated them into energy storage systems. We are revenue generating. We have eight months of field trial for grid-connected energy storage. The next three valleys of death are scale up by 10, scale up by 10, and scale up by 10. And that's our next three years of development. Now, there is a need for this for grid storage, right? We're talking about creating a new grid, people going more electric, uniting cars and

solar power and wind, especially when the sun doesn't shine, right? Storing up excess energy for when you can use it and smooth out the grid. This is that kind of solution. That's absolutely right. And there are two sides to it. One part of it is all of the hoopla about energy storage right now is focused on decarbonizing the transportation sector. If you look at the global emissions from transportation, it's about 14 to 15 percent of total CO2 emissions. If you look at the electricity, heat generation, and industrial sector, add those categories up, and it's about 45 to 46% of global emissions. So there's an enormous amount of,

I don't want to call it low-hanging fruit because it's not trivial, but there's an enormous opportunity to decarbonize some of the largest polluting sectors. And energy storage can be considered a force multiplier for renewables and the intermittency of renewables. If you have the sun, which only signs six to eight hours a day,

and you have the wind, which blows intermittently, but you have both of those renewables paired with energy storage, you've gone from 50% capacity utilization to 75% or 100% capacity utilization. That's part one. Part two is the economic effects of introducing renewables to the grid. As you add more wind and as you add more solar, those opportunities can be thought of as volatile power generation assets. And what that volatility actually means, it's like the stock market.

There's a supply and demand for electricity that is traded on a real-time market. And if there's not enough sun or there's not enough wind, the price of electricity is going to be more volatile. Batteries smooth out that price volatility over the long term and enable renewables. All right. Let me give you my blank check question here because I'm sure there's stuff you'd like to continue to do research on. And if I gave you a blank check and you had an unlimited budget, how would you spend at what are the problems that still remain? What are the challenges that you're looking into? The short answer is, from a macro perspective,

we would like to scale up to dislodge Goliath. And by Goliath, I mean that 95% of energy storage today is lithium-ion battery chemistry. There's a bunch of historical reasons for it, but most of it has to do with price and most of it has to do with availability. We believe in two years from now, if we scale up by a factor of 100, will be cost competitive with lithium Maya. But scaling up is a non-trivial application from a manufacturing and supply chain and

execution standpoint. And we essentially want the opportunity to dislarge the Samsung's of the world, the Teslas of the world, you know, the LG Chem of the world that have this 30 years of R&D, 30 years of financial backing with an inferior chemistry that is unsafe, that is not sustainable, and doesn't last for that 30-year utility level lifetime that we're looking for. All right. We will look forward to seeing your batteries. Eli Pastor, CEO of the Battery Startup, Polly Jewel based in Belrica, Massachusetts. Thank you for taking time to be with us today.

Thank you so much. This is Science Friday from WNIC Studios. Summer means camping, beaches, barbecues, and pesking mosquitoes to bug us for another season, right? They use their amazing sense of smell to sniff out their next meal, us. Hoping to figure out a way to get mosquitoes to leave us alone, one team of scientists asked what would happen if we trick their olfactory neurons, those cells responsible for smell, into being repulsed by the smell of humans? The answer turned out to be a lesson in biology.

Here to tell us more about that experiment, and its surprising results is Dr. Chris Potter, Associate Professor of Neuroscience in the Johns Hopkins University School of Medicine, based in Baltimore, Maryland. Welcome to Science Friday. Thank you for having me. So your original goal was to trick mosquitoes into being repelled by human smell. How are you going to do that? Well, what we were trying to do is we're trying to take an odorant receptor that normally responds to human odors.

in Anophilies mosquitoes. And instead of having that just in a very small subset of olfactory neurons in the antenna of the mosquito, we were going to put it in almost all their olfactory neurons. And in this way, when a mosquito would fly towards the human, for example, all those olfactory neurons would now get activated when before a lot of them were silent. And our hope was that that would be a repellent signal to the mosquito, that it's sort of like you're in a room that has somebody who has very strong cologne or perfume. You just need to get away from that.

And we were hoping the same thing would happen with mosquitoes, that if we were to trick them, humans would now smell so strong to them that they would try to get away from us. Well, do you have any past history with other insects where this has worked? Oh, yes. We tried this originally in Drosophila and Menagaster. It's a vinegar fly, and it works beautifully well there. So we thought, you know, perhaps naively that we could just bring this over into the Enophily system, into the mosquito system. And it would also work really well there. Because they would think we're just annoying.

that it'd be so overloaded, they'd want to get away from us, but did it work? It did not work. It did not work. And so what happened instead, instead of turning on these neurons, we actually shut them down, that we were expecting that the olfactory system of the Ennopolis mosquitoes would now be overwhelmed, but the exact opposite actually happened, that now the mosquitoes olfactory systems was shut down completely. Wow. Wow. That must have been surprising. That was surprising and a little bit confusing in the beginning.

We weren't sure what was going on. And so then we had to go and figure out, like, why wasn't it working like we expected it to? Did you ever figure that out? We did. So it turns out that in mosquito olfactory neurons, there seems to be a mechanism in the neuron itself, where if you overexpress an odin receptor, it actually shuts down that neuron. And so what it was happening is when we were expressing this odent receptor in all the olfactory neurons, all those olfactory neurons were now being triggered to shut down their odent receptor signaling.

So looking at the big picture, what did this experiment tell you about mosquitoes or about doing research in general? It's a little harder to do these things in mosquitoes. What it did tell us is that the olfactory system in mosquitoes is a little trickier than we expected that it has a lot of aces up its sleeve. And so we think that this mechanism that we've identified in mosquitoes might suggest that there might be a lot more adaptable to change. You know, we try to knock out one aspect of mosquito olfaction. There's another aspect. that will come in and take care of that. It'll fix it for them. So they have backups, but maybe backups of backups? That's right, yeah.

So we were looking at one class, one type of odor olfactor receptors called odor receptors, and we essentially knocked all those down. They were no longer functioning. And so what they did instead was to use their backups, their backup olfactor receptors. Those can then take the place of the odor receptors that we knocked out. Because this is very important for those receptors to work. That's how they live. They need to suck blood from people.

That exactly right. So this is such an important drive for them that if they don't, if they don't get a blood meal, that's essentially the end of the line for them. The blood is required from the females to produce eggs. So no blood, no eggs, that's the end of the line. And so there is such a strong evolutionary drive for them to get that blood meal that they have figured out all sorts of tricks, all sorts of ways to make sure that they'll always find a human and always get our blood. Do we know what attracts them? I mean, to repel them, you got to know what attracts them, right? It's true. Yes. There's a number of odorants that we give off on our skin that seems to be attractive to mosquitoes. These are like breakdown products of certain oily substances on our skin that give us kind of like the human odor to the mosquito. And they're super attracted to those. Unfortunately, there's nothing we've identified yet that is more attractive to mosquito than a human. So there's no good lure that you can use at this point that would work better than having a human. Did I hear you say that humans are their favorite food? For these anthropophilic mosquitoes, so the 80s egypti mosquitoes, Enophilis Gambi mosquitoes, they are their favorite food for those mosquitoes, yes. Wow. So if you're among animals, we're the choice meat in this thing. It's frightening. It's amazing. Yeah, it's frightening and disheartening because we know that we're their number one target.

Is there anything that will keep us from getting. eating alive, any kind of repellent we can suggest? Well, yeah, there's a number of repellents that are on the market that are fairly effective. So like Diet, for example, is the most commonly used insect repellent. We've been using it since the 1950s, and it does work quite well. One thing that does seem to increase your attraction, something to keep in mind for the backyard barbecue is alcohol consumption. You know, drinking a beer, for example, can you make you a little bit more attractive to a mosquito? The thinking is that it helps, you know, your skin gets flush, little bit warmer. And so when you're a little bit warmer, you're giving off a little bit more

odors that the mosquito can pick up on. Wow. Thank you for that because I'm not going to see that on a beer commercial this number. Thanks a lot, Chris. Yeah, thank you. Dr. Chris Potter is an Associate Professor of Neuroscience in the Johns Hopkins University School of Medicine based in Baltimore. We'll be right back after this short break. Stay with us. This is Science Friday from WNYC Studios. This is Science Friday. I am I reflato. When it comes to see, Sex, is there really any such thing as normal? I mean, what was once considered taboo can go mainstream, right? And much of what we consider recent developments in reproductive health care,

like birth control and abortion? Well, they've been around, been happening in some form or another for thousands of years. All that and more is contained in a new book called Been There, Done That. A rousing history of sex, it's by Rachel Feldman, friend of the show, an executive editor of popular science based in New York City. We thought that as part of our continuing coverage of the science of reproductive health, this book would offer some good historical footing, taking us back in time. So we assigned our time traveler, SciFrize Shoshana Buxbaum,

to speak with Rachel Feltman about her new book, and she joins us now. Hi, Shoshana. Hi, Ira. Now, I understand this book is chock full of fascinating animal facts. So what can gay penguins help us understand about human sexuality? Yeah, so you've probably heard about the numerous famous now gay penguin couples at zoos around the world. And it sure seems like a pretty recent phenomenon. It turns out that scientists and naturalists have actually been observing gay animal behavior for at least a century, actually probably longer.

Really? Yeah, but as Rachel Feldman told me, there's a long history of. projecting sexual norms of the time, however misguided, onto animals. Throughout recent history and sort of the natural sciences, you see the researchers inherent biases really coloring what questions they even ask. Naturalists observe either just really voracious or violent sexual behavior among animals or same-sex sexual interaction and just refuse to write it down. because they're like, that must be an aberration for the species.

Like there's no way that that can be common, normal, relevant. And so they just would leave it out. A lot of what we think of as normal is really based on like what researchers were even comfortable talking about. And in the 1800s, I can tell you that was not male penguins having sex with each other. That was definitely not a thing they were comfortable talking about. One of the other examples in your book that I just have to bring up. I can't do this interview without talking about it is the three goose relationship that you talk about in the book.

Tell me a little bit about this pretty actually common arrangement of how geese raised their young. So a while back in New Zealand, there was this goose known as Thomas. and he took up with this injured female black swan who people called Henrietta. This was around 1990. And 18 years later, according to the BBC, another female black swan showed up. And then she laid eggs. It turned out they were Henrietta's eggs because Henrietta was actually a Henry. And Thomas, this goose was a gay icon and no one had known this whole time.

the thruple eventually settled into a rhythm and then Thomas took on like a parental role as Henry went on to have 68 children. Oh my gosh, 68. Yes. Impressive. And according to research on black swans, at least for them, this setup would have actually probably felt pretty normal, you know, interspecies aspect of it aside. Black swans are known to have a few different potential setups for mating and parenting. But actually, according to at least some research, the most stable pairing is when there are two males and a female and they all stay together. This is a family structure that works from an evolutionary standpoint. For taught, your biological imperative is to make babies. And so people see sexual orientations that don't involve.

procrative sex as being somehow a strange exception to that. But we do see examples in the animal kingdom of situations where there being parents who aren't physically reproducing themselves as an evolutionary benefit. And so now any conversation about sex has to unfortunately get into some of the downsides. And it turns out, I learned, that romances between Neanderthals and early human ancestors actually led to them swapping STI sexually transmitted infections. What happened? Well, what happens that STIs are supernatural and normal and have existed for much longer than humans have? And HPV and HSV, which is herpes, we did have some trading back and forth.

HPV, we got that from Neanderthals and we gave them HSV. There were some really unfortunate headlines a couple years ago about how we killed Neanderthals with herpes. That is not true. So humans are unusual in that we have two strains of HSV-HRP-symplex virus. We have HSV-1 and HSV-2 are what's known as oral and general of herpes, extremely similar. And it's because one is the version that we evolved with in a more original sense, which gives us cold sores usually. And then the other one is one that we caught from some other primate relative, probably not through sex. It was probably more like one relative ate a certain primate and then maybe we had sex with the other primate.

It's a, you know, it's a twisted web we wove as early humans. So I want to pivot a little bit to a topic that gets a lot of conversation. That's contraception. And a lot of people think of it as a modern invention. but preventing pregnancy, just like STIs, are as old as sex itself. And one particularly eye-opening example that you write about in the book is that ancient Egyptians used a mixture of crocodile dung as a contraceptive device. How exactly did that work and do we know if it worked as a contraceptive?

Well, for reasons that are probably obvious, no one has, to my knowledge, tested this. this is pure speculation in terms of how well it would have worked. But it does make sense because the crocodile dung would have helped create kind of a physical barrier against the cervix. And it also would have helped change the pH of the vagina, which we know is a really valid method of birth control. In fact, like one of the most recently FDA-approved birth control products is a gel called Vexi that changes the pH so that it's not hospitable to sperm. And the crocodile dung was very similar. They often used honey as well, which we now know has potent antimicrobial properties, which is great if you're putting poop anywhere near your vagina, which is not something you should

do ever, just to be clear. And we see that combination of a cervical barrier plus a pH influencer again and again through history. There are sponges soaked with vinegar, in the Talmud. You see ghee being used by women in India thousands of years ago. People have been trying not to have babies when they have sex for a very, very long time. Yeah. And similarly to contraception, abortion is also very much not new as much as we tend to think of it as new. And access to abortion in the U.S. has been on like a lot of people's minds in these past several weeks. and especially, you know, the impacts of a reversal of Roe v. Wade, which was what made abortion legal in the U.S. to begin with. And people are pretty familiar with that. But the history of how abortion was banned in the first place in the U.S. is like not as widely known. And in the book, you talk about the history a little bit. So how did Horatio Robinson Storer and the creation of the American Medical Association lead to an abortion ban in the mid-1800s?

Yeah. So what's really interesting is, and pretty intuitive once you think about it, is that when you look back in ancient history, there isn't a lot of distinction morally or practically between methods of birth control and abortifacients because before we had any insight into the mechanisms of gestation, the line was a lot blurred. year between like stuff you took to end in early pregnancy and stuff you took like to not get pregnant and stuff you took in case you like might be just a little bit pregnant. And even up into

the 19th century, you see abortion and especially early abortion as really being seen as a personal issue. Like it's not to say that no one ever opposed it. Certainly there were religious institutions that opposed it and not just in recent history. But nobody was making laws around it. We see records showing that people terminated pregnancies. And Horatio Robinson's store was very much opposed to abortion. Where things got tricky is that he was one of the first like true OBGYNs and the American Medical Association was really in its infancy. And in fact, the idea of being a doctor in the modern sense was like pretty new. And the American Medical Association was, working on ways to medicalize medicine because for all of human history, you know, there may have

been people who were especially respected or known for the medical care they could offer. And there were also people performing abortions. And a lot of those people were midwives and other female health care providers. So it's now pretty clear that whatever Horatio Robinson Store believed, the American Medical Association supported his crusade against abortion because it was a way to distinguish themselves from midwives and other female providers of health care because abortion became this evil, dangerous, unseemly thing that women in back alleys would do. Even though these were like the women who had been taking care of other women's health for hundreds or thousands of

years. And that stood in contrast to OBJNs, who were these white men who had been educated and who would take care of you in a medical setting. The American Medical Association came out hard against abortion. They really laid the groundwork for abortion becoming illegal. What can taking a look through our sexual history, not our personal ones, our collective ones, help us understand about how we think about sex today. The main takeaway of my book is that we get so embarrassed about sex, we feel so much shame around it. We're really taught to believe that there is stuff that's normal and stuff that's not. And it's all like very much based on like very recent cultural hangups.

And no matter who you're attracted to or what you're into or what your goals are. when you have sex, you are really not alone. And humans have definitely done that thing. And I think that's a perfect place to end. So Rachel, thank you so much for being on Science Friday and talking about your book. Thank you so much for having me. Rachel Feltman is the author of Been There, Done That, a rousing history of sex. She's also the executive editor of popular science based in New York City. Ira? Syfry Shoshana Bucksbaum. If you want to read an excerpt of the book on our website, go to sciencefriiday.com slash sex history. ScienceFriday.com slash sex history. This is Science Friday from WNYC Studios. Artist Annie Loo's thought-provoking artworks

contain anywhere from a dash of science to a whole heaping spoonful of it. She's used organic chemistry to concoct perfumes that smell like people emotionally close to her, and engineered a device that enables the wearer to control with their mind the direction of swimming sperm. Digital audio producer Dee Peter Schmidt visited her latest exhibition in New York and brings us this story. Annie Lou became a parent right before the pandemic started. And the pieces in her latest show were inspired by her postpartum experience. She gave me a guided tour of some of her work in the gallery and told me of a

about the science she used to make them come to life. And it all started with her take on a breast pump. Connected to a small white opaque box on the floor was 328 feet of clear tubing looped around on top of itself. A white liquid pulls through the tubes and the effect was pretty hypnotic. This is a synthetic milk that I designed to mirror the color of my own breast milk.

I wanted to use breast milk but it wouldn't be stable for the duration of the show and it was tricky actually to kind of create a formula that would have the look of breast milk. I was trying to capture the rhythm of my breast pump because it was that sound and that rhythm that caused me to let down. Letting down is this mechanism by which your breasts will eject milk. And often that stimulus is your baby's cute face or the rhythm of their suckle. And I thought that was so interesting.

As an artist that was with technology, it was like, wow, my relationship to this technology is almost seamless. Like I kept thinking about breaking down these boundaries between animal, machine, human. My breast bump is programmable so that you can find the exact frequency that works for your body.

And after I found it, that was like the trigger. I like needed that particular rhythm. So it's kind of like, so what you're seeing here is a 3D print of a pig's uterus. The pig was chosen because we've already genetically engineered pigs to produce organs for transplant.

And I was also thinking a lot about the parallels between livestock and women, weirdly, in terms of the exploitation. Yeah, I made all of this work before the formula shortage, before our reproductive rights were even more under threat. In doing all of this research, I started to think a lot about the biopolitics of why we regulate the reproductive systems of women so much. Like, are we really just factories that make more citizens, more workers, more soldiers, more consumers? Right after my children were born, I became kind of interested and disturbed by toys because they were so overtly gendered. And I became interested in toys because I felt like they are almost like little simulations of reality that we want to teach the next generation. Toy selling websites like Walmart and Amazon often tag toys as being intended for girls or boys. Lou and a colleague scraped those categories along with toy names and descriptions and fed that data to a machine learning algorithm to create new 3D printed toys.

Some of it is kind of quirky. The English is not perfect. So from the girls' data set, it invented things like OMD, lights out unicorn party. I see one that says, yo, my smart purse. And from the boys data set, it invented things like brain bolt blaster, World War III electronic battling game with single target. So you can see like a lot of the girls' toys are focused on appearance. There's lots of makeup kits, lots of princess. And then the boys' toys are very violent, actually, tons of weapons, lots of simulations of war. And so I use the machine learning algorithm

kind of like as a mirror to hold up to society. Like, oh my gosh, look what we are doing. Look how strange. Look how arbitrary. And is this what we want to continue to perpetuate? If you're in New York, you can catch Annie's exhibition Ecologies of Care at the Cucci-Frito's gallery and project space from now until July 30th. And if you can't make it, you can see photos and videos of the exhibition at ScienceFriiday.com slash postpartum. For Science Friday, I'm Dee Peter Schmidt. Thank you, Dee. Hey, before you go, can you fill us in on some of the folks who helped make this show happen?

Sure thing. John Dankoski is our director of news and audio. Annie Niro is our individual giving manager. Flissomeres as our office manager, and Charles Berkwist as our radio director. Thanks for listening. Thanks again, Dee. And that's about all the time we have for this hour. B.J. Liederman composed our theme music.

and of course if you missed any part of this program or you'd like to hear it again. Yes, subscribe to our podcasts. Have a great weekend. I'm Ira Flato.