Pod Insights The Weirdest Thing I Learned This Week What Rats are REALLY Saying, Cosmic Caffeine, Lamarck was RIGHT?! About this episode Tom Lum joins the show to reveal what rats are ACTUALLY saying to each other. Plus, Rachel talks about the color of the Universe, and Lauren explains one evolutionary exception.
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Transcript 11,418 words · 9 speakers
Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
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1:33 Rachel Feltman? At Popular Science, we report and write dozens of science and tech stories every week. And while most of the stuff we stumble across makes it into our articles, we also find plenty of weird facts that we just keep around the office. So we figured, why not share those with you? Welcome to the weirdest thing I learned this week from the editors of Popular Science. I'm Rachel Feltman. And I'm Lauren Lefer. And I'm Tom Loam. Tom, welcome to the show. We're so excited to have you on.
2:04 Rachel Feltman? Would you tell our listeners a little bit about yourself?
2:06 Speaker 04 Yes, I make science videos on the internet. There's a little thing called the internet for folks like, for folks like Scienceific American, SciShow, for my own videos. I also co-host the podcast Let's Learn Everything on the Maximum Fun Network with my friends Caroline Roper and Ella Hubber, and also the live game show in New York City, Our Findings Show. Okay, I had to, had to make sure I, I make, had to make sure I got everything. I apologize. I'm, I will do any silly science thing that people will let me. And we just wanted to be here.
2:39 Rachel Feltman? That's how I should start encapsulating my career too.
2:46 Rachel Feltman? I'll do it, I'll do it, just ask.
2:48 Speaker 05 Silly science for hire.
2:50 Rachel Feltman? Yeah.
2:51 Speaker 04 I will also say, if you don't mind me saying, this is technically the second time I've been on this show technically, because in 2021, the very first TikTok I ever posted, that was the video that I ended up, is the reason I'm here now, was mentioned on an episode of this show.
3:12 Rachel Feltman? Was it, was it the bees one?
3:13 Speaker 04 It was the bees one.
3:15 Rachel Feltman? Oh, my gosh, I totally, I did not put that together, but as soon as you said it was a TikTok that we'd mentioned on the show, I was like, it's gotta be the bees.
3:25 Speaker 04 And it's, it's very funny to me because, oh, because I wasn't, I wasn't, at the time, I wasn't a person on the internet, in quotes. And so my username is Tom Lumperson, because that was the most, it was originally gonna be like Tom Lumdev when I was gonna be a computer person or make video games. And at the last minute, I was like, I'll make it the most generic name to apply. And so it was just person. But as a result, in the episode, I am referred to as Tom Lumperson, which I did get a lot in the early TikTok days. It is a common mistake.
3:55 Rachel Feltman? Oh, boy.
3:57 Speaker 05 Lumperson.
3:58 Speaker 04 So I, the only reason I agreed to this was to, to, to correct the record on that, and then I'll take my leave.
4:02 Rachel Feltman? God, you did. But listen, I remember that episode and it was really fun, so we will link to that.
4:08 Speaker 05 What is the bees TikTok, though? What was the information?
4:12 Speaker 04 It's that bees have a sense of time, and most importantly, they can get jet lagged. If I focus really hard, I think I can recite the TikTok. I've, it's just been so, in college, I learned my favorite science story ever, which.
4:28 Rachel Feltman? But yeah, we will link people back to the Tom Lumperson
4:33 Speaker 05 Tom Lumpercy.
4:34 Rachel Feltman? Lumperson episode and the TikTok in question. So everybody can get the whole backstory. That's incredible. Well, and listeners, I asked Tom on because like you said, you've been doing videos for Scientific American where I'm doing a podcast, Science Quickly. And obviously, all your videos are great. It's not like they've suddenly become great now that you're at SIAM, but they've really been like hitting.
5:01 Speaker 04 Yeah, well, I mean, I'm I'm out of short form retirement almost because I just had been not doing it for a while and then have been doing it again. And I was like, oh, wait, yeah, this is fun. I miss, I do miss doing this and it's great to, yeah, I posted a little like when it, when I started doing it, video explaining how I felt about it. But I, yeah, it's, it's just been, it's been great. So I'm glad, I'm glad it feels that way.
5:24 Rachel Feltman? Yeah. Well, awesome. We're excited to have you on officially for the second time and we'll roll right into the show. So on the weirdest thing I learned this week, we start by offering up a little tease about some kind of fact or story that we found in the course of reading, writing, reporting, et cetera, and decide which one we just absolutely have to hear more about first. Then, once we've all had time to spin our little science yarns, we reconvene and decide what the weirdest thing we learned this week actually was. Lauren, what's your tease?
5:53 Speaker 05 Oh, okay. This might be a little wonky, but I'm sticking with it. My tease, Lamarck was right, justice for Lamarckian inheritance.
6:04 Rachel Feltman? Drama.
6:05 Speaker 05 Yeah. Bringing back some really old science beefs.
6:09 Rachel Feltman? I love that. Tom, what's your tease?
6:11 Speaker 04 My tease is so long-winded. I wish I had like a real quippy one, but my tease is in a bunch of different ways, New York City rats are weirdly similar to New York City people. And we figured that out with some really cool tech.
6:24 Rachel Feltman? I mean, yeah, I'm excited to hear a science proved it, but I could have told you that.
6:30 Rachel Feltman? They're part of it.
6:31 Speaker 04 I did a, I did a short video on this for SIAM, but there is a lot to dive into. And so I'm so glad I have the excuse to really, really dig deep, like a rat into trash, into all these details.
6:42 Rachel Feltman? Awesome.
6:42 Speaker 05 Spiritually, I know that when I was living in New York and I would look a rat in the eyes, I felt a kinship there. I'm not surprised.
6:51 Rachel Feltman? My tease is that I'm going to talk about cosmic lattes.
6:56 Speaker 04 Ah.
6:58 Speaker 05 Short, sweet, sweetened oat milk?
7:02 Rachel Feltman? Yeah, there's probably a good amount of oat milk in the cosmic latte.
7:04 Speaker 04 I think I know this on a pub trivia fun fact level, but I'm very curious. I've not dug any deeper, and so I'm very curious to learn more. To be a cosmic latte barista by the end of this hopefully.
7:16 Rachel Feltman? Well, I can, I'll dive right in then.
7:20 Rachel Feltman? So this is the story of how we figured out the average color of the universe, depending on how you define that, which then had to be corrected to a decidedly less interesting color, but which is still very cool. We're still very happy that this happened.
7:36 Rachel Feltman? So back in 2002, a couple of astronomers, Ivan Baldry and Carl Glazebrook, presented their research on what they called the cosmic spectrum, which is not the cosmic latte, but is related. So they were analyzing data from the 2DF Galaxy Redshift Survey, which measured light from more than 200,000 galaxies. It basically looked at two big old slices of the universe to a depth of like 2.5 billion light years.
8:03 Speaker 04 Wow.
8:05 Rachel Feltman? At the time, it was the world's largest redshift survey, but it was overtaken in 2003 because people always be making bigger telescopes, but for that one year.
8:16 Speaker 04 It's like the Stanley Cup, they gotta hand it over to the next telescope.
8:18 Rachel Feltman? Yeah, it was actually the biggest survey from 1998 to 2003. So it had a little bit longer of a reign, but this data analysis came out in 2002. And basically, they used all that data from this survey to construct what they called the cosmic spectrum, represented all the sum of all the energy in that part of the universe emitted at different optical wavelengths of light. So it kind of looks like a prism color spectrum. Kind of thing, totally unintelligible, except that it's a rainbow. Unless you are these dudes doing this research. And their primary motivation for doing this was actually to learn something about the history of star formation in the universe. Basically, if you know what you're looking at when you look at the cosmic spectrum,
9:03 Rachel Feltman? it has these dark lines and bright bands throughout it, which correspond to the emission and absorption of different elements. And the strength of the dark lines is determined by the temperatures of the stars that are contributing to the cosmic spectrum. Older stars are cooler, so they produce a different set of lines compared to hot, young stars. Hot, young stars.
9:28 Speaker 05 The cool to hot spectrum.
9:30 Rachel Feltman? Yeah, exactly. And so like by analyzing that spectrum, the idea was they could work out the relative proportions of young to old stars and sort of, yeah, infer what the star formation rate was in different eras of the universe.
9:47 Speaker 05 Is the, is the idea to find out the age of that part of the universe? Or like, is it, is, I'm gonna hold this question, never mind.
9:55 Speaker 04 I know we, we, this is, we talk about it all the time in astronomy, the age of things, but just every so often, when someone breaks it down, it's just, yeah, we just looked at a portion of the sky, did some math, and we know how we can like shoot a beam of age detection at stars, was it like billions of light years away?
10:16 Rachel Feltman? Yeah, yeah.
10:17 Speaker 04 That's wild.
10:20 Rachel Feltman? And their takeaway was that the majority of stars in the universe today formed more than five billion years ago, which is borne out by other research of this type, where the idea is there was a time when the universe was making way more stars because there was more ambient gas and material around.
10:38 Speaker 04 But now with streaming and TikTok, you just don't have the star power anymore.
10:41 Rachel Feltman? It's true, yeah.
10:42 Speaker 05 Yeah, lots of influencers, very few stars.
10:44 Rachel Feltman? Yeah, exactly.
10:47 Rachel Feltman? But meanwhile, they decided to just have a little fun, just on a lark.
10:51 Speaker 04 That's, that's, that's my favorite part, because here's what I assume, and I apologize to interrupt, because this all is like, the very interesting data. But I, I, is, am I right that like, it's just, they were just sort of like, well, we have the data. What if we just click some all, just for fun? Okay.
11:06 Rachel Feltman? Exactly.
11:06 Speaker 04 I love scientists so much.
11:09 Rachel Feltman? So yeah, they were like, on a lark, let's just see what color the universe is. What does that question even mean? How are we defining it? It doesn't matter, it's just a little footnote in our research. Big mistake, guys. Anyone on this recording right now could have told them, that is obviously the part people are gonna
11:27 Speaker 04 And that every, yeah. Everyone's gonna wanna do a thing on.
11:31 Rachel Feltman? So yeah, they decided they were gonna estimate the average color of the universe. By that, they meant if you could trap all that light that they were looking at in their spectrum in a box, so that it was all just one color. And you could see it from the perspective of a human on Earth. And also, the universe would have to stay still for a second, because the expansion of the universe means galaxies are constantly shifting to be more red from our perspective. So there are a lot of caveats here.
12:01 Rachel Feltman? But they came up with this color that they said was right between medium aquamarine and pale turquoise.
12:10 Speaker 05 Are those not the same color? Medium aquamarine and pale turquoise?
12:15 Speaker 04 A lukewarm blue-green.
12:16 Rachel Feltman? Yeah, you're not wrong.
12:17 Speaker 05 I feel that these were scientists and not like, design experts. They weren't like, up on their Pantone colors.
12:23 Rachel Feltman? Yeah, they were like, what, what hex code is it? Between these two? And they were like, this makes sense, because turquoise is a very particular mixture of red and blue. And that kind of reflects the stage of the universe we're at. When the universe was really young, the cosmic color would have been more blue, because there were a lot of young stars, which tend to shine blue. And then the universe has aged, so there are more old red stars, and so that's like, making it greener.
12:52 Speaker 05 Wait, reds, more red stars is making it greener?
12:56 Rachel Feltman? Yes.
12:58 Rachel Feltman? What? The it's I'm gonna we're coming around to a to a plot twist. Okay, cool. But they were able to to to come up with a reason why the green was the right color. But it turned out it was the wrong color. Spoiler alert. And
13:18 Rachel Feltman? yeah, another important factor.
13:20 Speaker 04 Is your lattes are your lattes not aquamarine, somewhere between mild aquamarine and?
13:25 Rachel Feltman? It's a very Star Wars latte.
13:27 Speaker 04 Yeah.
13:28 Rachel Feltman? So.
13:28 Speaker 04 They have Zeeb Zobo Grande.
13:33 Rachel Feltman? And yeah, one important thing buried in there is that the color of the universe is going to change over time. At one point, it would have been very blue and one day it will be very red. But it turned out they hadn't gotten the color quite right. Mark Fairchild, an expert in color science, who I learned is retiring sometime in 2026. So happy retirement, Mark, is credited with helping them correct the error. I'm not sure if Mark is the only person who informed them of their mistake or if they got like a flood of emails from agitated color experts. But he diagnosed the issue. And the long and short of it is that they had used a free software program to identify that greenish color. And it hadn't been calibrated correctly. The white point was off.
14:17 Rachel Feltman? The white point is the point at which light appears white to the human eye in different kinds of illumination. If you're not someone who's had to spend a lot of time in Photoshop.
14:28 Rachel Feltman? And Glazberg was actually quoted as saying, this was all because they hadn't taken the color science seriously enough, which makes sense, given that this was meant to be a footnote in their serious cosmic spectrum paper. But like I said, as any of us could have told him, obviously, when you presented this at a conference with that interesting, funny little footnote, that's what people were gonna run with. And Glazberg was quoted saying, it is embarrassing, but this is science. We're not like politicians. If we make mistakes, we admit them.
14:57 Speaker 04 Yeah.
14:58 Rachel Feltman? Yeah. So, yeah, Fairchild realized that this random piece of freeware was actually using like a slightly pinky color as white, which caused a huge green shift. And they were like, yeah, if you look at all the light in the universe from a room where the light is neon red, then it's gonna look turquoise.
15:19 Speaker 04 They're like, that's what I meant. That's what I meant. I have a lot of over lighting in my apartment. That's why I was just, yeah.
15:26 Rachel Feltman? But it's not a standard perspective. And when they corrected the white point, the color was actually on the slightly pinkish side of white, a slight beige color. In fact, if you look back at the researchers' very 2002 explanatory webpage about their findings, they make a big deal out of the fact that this is so close to white that you probably can't even tell the difference. I disagree, but it's certainly in the off-white family.
15:55 Speaker 04 I don't know why they're still picking fights with color people. Didn't they learn their lesson?
15:59 Speaker 05 I still have a follow-up here, though. It's like, the light they're mixing is still predominantly blue light and red light, and somehow they're coming out with white light? I guess it's, they're like, I just have questions. What's going on?
16:14 Rachel Feltman? Yeah, fair. I think it's, it's a really kooky thought experiment, is the answer. And there are so many stars. We're mostly seeing blue tinted stars because of how far away they are. But there's more and more red in there. So apparently, the mostly blue with some red is shifting us to a true white situation. Or at least a pinky beige.
16:43 Speaker 05 When you add colored light together, it's like more of that additive thing where you end up with the white spectrum as opposed to like, printing colors.
16:51 Rachel Feltman? Exactly. Yeah. And of course, the exact shade it appeared as this white point issue hints would depend on what kind of light you were surrounded by. If we were standing in daylight, the color would be like a faint red. In indoor light, the color would be more blue. But they did their best to approximate, like, you're in a dark room staring into a box of universe, which I wish.
17:19 Rachel Feltman? And they were like, yeah, it looks beige. This is actually a quote, "It looks beige. I don't know what else to call it. I would welcome suggestions."
17:27 Speaker 04 I just imagine like CERN has created this imaginary device and like they've, they've spent, spent trillions of dollars creating this isolated room that averages all the light. And then they look at it and they're like, I don't know, it's beige.
17:42 Speaker 05 I don't know how that makes me feel about our universe as a whole, though. It's like you average all out. It's like, we live in beige universe.
17:49 Rachel Feltman? Yeah, but not, you know, one day we'll live in red universe and then.
17:53 Speaker 04 Yeah. I feel like that's, that's less of a fun universe, actually, is, is an exciting color.
17:58 Speaker 05 I want to keep the colors separated and continue to live in like my bisexual lighting universe. Red and blue, either side, everyone looks hot.
18:06 Rachel Feltman? Yeah, you're, I think that's so right. I think that's correct. That's the design perspective, not the astronomer perspective.
18:16 Speaker 04 I will say, and can I ask, do you know if the researchers came up with the name Cosmic Latte?
18:22 Rachel Feltman? No, and that is.
18:23 Speaker 04 Okay, I was, I was gonna say, whoever did, that's great branding, because if you see this, this, this, yeah, a beige they might describe as, oh, somewhere between off eggshell and medium gray. It's like Cosmic Latte, and I feel like has, has had such good branding that most people don't know the, the goof up at this point.
18:41 Rachel Feltman? Yeah, totally. Because they, they called the original turquoise color something like, just like cosmic green or something. But you know, once beige was in play, they were like, we can't, you can't just call it cosmic beige. So they did put out a call for, this is so 2002. They just asked people to email them. If this happened today, it would be a huge competition. And it would have been called like Beige McBeige Face.
19:11 Speaker 04 Sonic x Shrek.
19:15 Rachel Feltman? But so, yeah, the names that they solicited by email, so there were very many of them. There was Cosmic Latte from a guy named Peter Drum with six votes. Cosmic Cappuccino, oh, sorry, Cappuccino Cosmico, also by Peter Drum, with 17 votes.
19:34 Speaker 04 What?
19:35 Rachel Feltman? Several people entered variations on Big Bang Buff, Big Bang Blush, or Big Bang Beige, which collectively got 13 votes. They were voted on by the astronomers who were involved in the paper. Several people entered Cosmic Cream, which got eight votes. Someone entered Astronomer Green. I guess they hadn't gotten the memo. The new swatch. Or it was like a diss, like astronomers will think this is green.
20:03 Speaker 04 Or we find out, it's like, Kevin, you are colorblind.
20:06 Rachel Feltman? Or they were just, they were in a red room. Yeah, yeah.
20:10 Speaker 04 Yeah.
20:11 Rachel Feltman? But eight people did vote for that.
20:14 Speaker 04 What?
20:14 Rachel Feltman? Astronomer Almond by Lisa Rose got seven votes. Skyvery by Michael Howard.
20:20 Speaker 04 Oh, hold on. Now, now, hold on.
20:24 Rachel Feltman? Yeah, yeah. Skyvery, I think that slaps a little bit. That's like, that's like a Mormon mom's name.
20:32 Speaker 04 That's true. And, and, and I thank you very much, Lauren, for convincing me back.
20:37 Rachel Feltman? Kaylin and Skyvery. Univege was sent in by several entrants, got six votes. Several. Several entrants. Cosmic Khaki, that was an unknown submission with five votes.
20:52 Speaker 04 But also who amongst us has not been in the, coming up with a science pun name, uh, you know, Google Doc, or you have a list of science words on one of those?
21:00 Rachel Feltman? That's the whole profession.
21:04 Rachel Feltman? And then the last one on the list is primordial clam chowder.
21:08 Speaker 04 Oh. Okay, now, hold on.
21:11 Speaker 05 Sky soup.
21:12 Rachel Feltman? Creamy sky soup.
21:14 Speaker 04 Timorial clam chowder.
21:17 Rachel Feltman? And that was from an unknown entrant. If you're out there, please step forward.
21:21 Speaker 05 That was actually from the universe.
21:23 Rachel Feltman? Yeah. And it only got four votes, which I think is really unfair.
21:28 Speaker 05 People in the 2000s didn't have any sense of humor.
21:30 Rachel Feltman? That's so true. So, as you may have noticed, cappuccino cosmico really ran away with the vote, but they actually liked this guy Peter Drum's other suggestion, cosmic latte, because they were like, well, latte means milk in Italian, which is Galileo's native language, and latteo means milky, like the milky way, which is via lattea in Italian.
21:58 Speaker 04 Because it's named, we did this on our podcast, it's named after a believer, oh god, a myth of breast milk shooting across the sky because it looked milky in the sky, I believe. I believe that's true.
22:10 Rachel Feltman? Yeah, I think that does sound familiar.
22:12 Speaker 05 Sorry, is cosmico cappuccino, or what was it?
22:16 Rachel Feltman? Cappuccino cosmico.
22:18 Speaker 05 Is cosmico not legit Italian? Is that like an Italian brain rot meme?
22:23 Rachel Feltman? I think so. I think so. And, yeah, they also claimed to be caffeine biased, so that's why they went with cosmic latte over some of the other suggestions that had gotten more votes. I'll wrap up just by saying that the researchers have sort of an FAQ on their, again, very 2002 webpage, explaining their findings. And they've really, it makes it very clear that some of their colleagues were like, absolutely not, this is nonsense. So, one of the cues that was apparently frequently aimed was, does not the universe
23:06 Rachel Feltman? consist mostly of transparent space, which is actually close to black in color because it contains far more interstellar and intergalactic non-luminous gas, dust, and perhaps dark matter that absorb light than it contains stars that radiate light?
23:18 Speaker 04 Such a frequent cue. All asking that.
23:22 Speaker 05 That was the, the first thing I thought that was average color of the universe. That's black. That's no color.
23:27 Rachel Feltman? I think the question is valid. The phrasing makes me curious about who exactly was asking it.
23:34 Speaker 04 We all say in unison that exact sentence.
23:38 Rachel Feltman? And their answer was, black is the absence of light. We were looking at the combination of all of the light colors. And when we see black, when we look up at the sky, it's just because our eyes aren't sensitive enough to see faint galaxies. So, yeah. And then the next question is, but still, the average color of the entire universe is probably close to black, isn't it? And their answer was, the extragalactic sky is black to the naked eye. However, black contains no information, other than galaxies are too faint to see to the naked eye. The way we have defined the color, the hue derived from the cosmic spectrum is related to the history of star formation in the universe. It would not be interesting or informative to say the universe is black.
24:22 Speaker 05 Okay, but wait, wait, wait. Were they looking at only visible light? Or were they also including like UV light in this spectrum?
24:31 Rachel Feltman? They were looking at the visible light spectrum.
24:33 Speaker 05 Okay. So, yeah, I mean, I feel like if you included all the light specifically, you might end up with something else.
24:40 Rachel Feltman? Yeah, I mean, like
24:41 Speaker 04 Sir, build another box!
24:45 Rachel Feltman? Like I said at the beginning, they created very specific constraints, because there is no right answer to this question, because you can't always say, well, what do you mean by that?
24:56 Speaker 05 And that's science.
24:58 Rachel Feltman? Yeah, and that's science.
25:00 Speaker 04 I gotta say, I think it does, it's a good, like we were joking, like, this is a goldmine of a like fun fact. But I do think it does offer some genuinely good follow-up questions. Because I was like, oh, yeah, that is interesting. I guess, yeah, the blackness of space is the absence of information. And I also, God, I love, I love the drama between the different factions throughout the story of the researchers, and then the color science people, and then the general public.
25:29 Rachel Feltman? Yeah, no, and whenever, whenever they addressed a question that amounted to like, why do this? What, if, if there are so many caveats to what you mean by this being the average color of the universe, like, why'd you do it? And they were like, because it was fun, and nobody was supposed to notice, and you all hate fun!
25:51 Rachel Feltman? Basically, well, they they wanted it to be like a learning tool, like a thing that made people curious and that then they got lots of follow up information on. And unfortunately, most people just didn't care about the follow up information. But that's science communication.
26:07 Speaker 05 Well, it worked on me because I have questions for these people.
26:12 Rachel Feltman? Well, I bet their inbox is still open. I bet I bet they're still fielding all of those all those cues today.
26:20 Speaker 05 I want to know what the cosmic latte would taste like.
26:23 Rachel Feltman? Oh, yeah, that's important. All right, we're gonna take a quick break and then we'll be back with some more facts.
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27:38 Rachel Feltman? Okay, we're back. And Lauren, speaking of beefs between scientists, what's up with Lamarck?
27:46 Speaker 05 Yeah, okay, so I'm not going to start with Lamarck or Darwin or Mendel or any of those guys. I'm gonna start with a question, which is hypothetical. Let's say you you cut off your hands and reattach them wrong. So left on right, right on left, then like years into your kind of like backwards handed life, you had kids. What would those kids' hands look like?
28:07 Speaker 04 I would think. They would have right on right, left on left. I believe I took biology.
28:14 Speaker 05 Yeah, yeah. So assuming all went well, their, their hands would not be backwards. But what if that's not always the case? I am here to talk about some wild, still unexplained and underexplored experimental results from the 1960s that like have the potential to really complicate the way we think about genetics and evolution. But first, we need some background. We need to make sure everyone's on the same page. So basically, we, we all know mostly how inheritance works. Organisms have their genes organized in DNA, which determine traits. Offspring inherit DNA from their parents over generations. Lineages with more beneficial traits win out, reproducing more, passing those traits along, yada, yada, yada, selection pressure, disease, the fight for resources.
28:58 Speaker 05 That all limits the spread of damaging mutations. And then through time, the genetics of a population shift. This is what we know from the work of Charles Darwin, from Gregor Mendel, who's the monk with the pea plants that you probably heard about in high school biology class. But through the history of biological science, there've been all sorts of other ideas about inheritance and largely debunked proposals for how organisms can further traits on to the next generation. So one of the classic flawed explanations for how we ended up with a planet full of biodiverse organisms, all doing different things, was Lamarckian inheritance. Basically, this French zoologist, Jean Baptiste Lamarck, had this idea that traits were determined by what was needed to survive in the world and that changes incurred during
29:41 Speaker 05 one's lifetime would be passed on to the next generation. Had this idea that traits were determined by what was needed to survive in the world and that changes incurred during an organism's life would be passed on to the next generation. He had these four primary pillars of evolution. We only really have to care about one. For this, for the purposes of this story, and that is, in his own words, quote, "All that has been acquired, traced, or changed in the physiology of individuals during their life is conserved through the genesis reproduction and transmitted to new individuals who are related to those who have undergone those changes." A lot of words to say, if you change something while an organism's alive, its offspring will have that same change. So if you cut off the hand, put it on backwards, the baby's
30:23 Speaker 05 gonna have the backwards hand. That's what Lamarck thought. The classic example he gave to prove this idea was, was the giraffe. Yes. So the way that Lamarck explained giraffes' whole deal is that over generations, the animals were trying to reach taller and taller leaves on the trees. They were stretching and strengthening their necks. With each subsequent generation, all that effort paid off in the form of baby giraffes with longer and stronger necks. This is like a completely unrelated aside, but I used to live a block away from a Pilates place in Brooklyn that had the tagline, quote, "Get leaner, stronger, and longer," plastered across all its windows. I've always wondered if, one, can Pilates make you taller? But two, I think Lamarck would have loved Pilates.
31:04 Rachel Feltman? Listen, okay.
31:05 Speaker 04 That's my favorite Daft Punk song also, "Get leaner, stronger."
31:08 Rachel Feltman? Listen, as somebody who occasionally tortures myself with Pilates, a modality I love to hate and hate to love. It does, it's all about like spine alignment and like improving your core. So it does definitely make you stand taller and can like alleviate some of that like cord compression that most of us have.
31:31 Speaker 05 Can you reach taller leaves on the trees now?
31:34 Rachel Feltman? I think not to that degree.
31:35 Speaker 04 And will your offspring reach taller leaves?
31:36 Rachel Feltman? Probably not.
31:38 Speaker 04 Lauren, I have to say two things. One is that the giraffe story is actually quite compelling because it, what it points to is this sort of like secondary and tertiary effects of evolution that like aren't as clear, where it's like the, these selective pressures are a little more indirect than, oh, you're better at a thing, therefore you, you know. And so in some ways, I'm like, oh, I do get it. But the main thing I want to point out is the fact that you could have led with the giraffe story, but instead you, you pitched your new sitcom pilot, My Backwards Hand's Life, instead.
32:09 Speaker 05 Yeah, well, I do think there should be an MTV show. Well, actually, is MTV going under? I think they're not going to exist next year or something. But the backwards hands thing, it's going to make a lot of sense in a minute. I promise.
32:18 Speaker 04 Wait, is it actually? Oh, oh, okay.
32:21 Speaker 05 Okay, it's gonna be important. Lamarck is really just like a way to, we'll get to it, it's kind of a way to understand this crazy thing that happened in the 60s.
32:30 Speaker 04 Oh, boy.
32:30 Speaker 05 But back to the giraffes, like, we all intuitively and clearly know this isn't how evolution works most of the time. You cannot get swole and then expect your kids to be born like automatic beefcakes. It doesn't unfortunately happen that way. But there is a little nuance here, and a lot of it you probably already know about. Like, epigenetics has been this buzzword since 2010. In the year of our Lord 2025, you've likely heard about it. It's cool stuff. It adds some spicy flavor to our ideas about genetic inheritance. Basically, it outlines a mechanism by which things happen to you in your life, and those things can in fact influence the genes of the next generation. This happens because, like, major stressful events, for instance, can shift how DNA, even in our sperm and
33:11 Speaker 05 egg cells, get expressed through this process called methylation. Still, though, epigenetic inheritance relies on DNA organized in genes. And that's not what I'm here to talk about. If you want to know more about it, you should like 100% read about epigenetics. Again, it's very cool. But I want to talk about something weirder.
33:29 Speaker 04 Podcast topic episode of Let's Find Everything about epigenetics, if you want to listen to that. But anyway.
33:32 Speaker 05 Yeah, great resource. Listen to that. Not to this. This is something different. I'm here to talk about this guy Tracy Sanborn, born and raised in Baltimore, so a hometown hero for me, and his paramecium experiments. So, paramecium, they're these single-celled eukaryotic organisms. So, they're eukaryotic, they're not, they're not bacteria, they're like closer to animals. They have lots of-
33:54 Speaker 04 They have a nucleus, is that?
33:56 Speaker 05 Yes, yes, they do. And they have lots of little appendages all over their bodies. You might think of them as like many little hands, called cilia, that help them move around and interface with the world. And usually the cilia on a paramecium, they all move in concert in one direction to like, make their movements efficient. So they have a kind of like handedness, like all their paramecium on one side go this way, all at once on the other one side go this way. They're kind of like, I'm doing something visually that is not coming through on the microphone.
34:25 Speaker 04 I'm just starting to piece together. I'm like, is this where this is going? But yes, continue. But that's fascinating. I did not, that's wild, yeah.
34:33 Speaker 05 Yeah, so little, little paramecium cillium appendages and paramecium critically, they have this like odd kind of hybrid mode of reproduction. So they, they produce new offspring asexually, basically just by photocopying themselves via DNA replication and cell division. But then they also exchange genetic information sexually by hooking up with other paramecium and swapping bits of DNA. This sexual process, it doesn't instantly lead to multiplying offspring, but it like down the line, if you do that enough, when you have offspring, they'll have like slightly different genes than you have. And it's, it's a route for evolution via natural selection to, it's a route for evolution via natural selection to occur. Basically, paramecium aren't genetic dead ends. But in theory-
35:17 Speaker 04 Fascinating. So they're just sort of like, hey, you, I have some spare DNA you want. Yeah, I might use it a little bit. Who knows?
35:21 Speaker 05 Yeah, they just meet up and swap stuff. They're just, they're like-
35:24 Speaker 04 Swap me?
35:25 Speaker 05 Yeah. It's like Facebook Marketplace. So, so through this kind of like dual system, in theory, change from generation to generation with paramecium, it should happen, but it should be like slow and a little random. And most offspring should just look like whatever the blueprint of their parents' DNA dictates. Enter Tracy Sombor. He did like a whole bunch of foundational paramecium experiments, which led to these little single cell guys becoming like a really critically important model organism. He discovered things like mating types and how to breed paramecium in lab, et cetera. He also did this thing, which I think is like very much in the spirit of those astronomers where he was like, let's just have
36:04 Speaker 05 some fun with it. He, he like, yeah, he like collaged paramecium Frankenstein's style.
36:11 Speaker 04 Oh.
36:11 Speaker 05 He like would take this single cell, he would chop off part of it or some of its cillia, and then he would just put it on backwards. He'd flip it around, attached in the wrong direction. And then he'd just watch that paramecium, follow it, see what it did, see what it was up to, and see what its offspring looked like.
36:26 Rachel Feltman? An experiment that would be horrifying at a larger scale, but with protozoas, I think we can, we can allow it.
36:33 Speaker 04 I think that's, yeah. I think that's, is that vegan, I think? At that point?
36:37 Speaker 05 Who could possibly say, I don't know what the ethics looked like for, I don't, I don't know if you have to do ethic, ethics for
36:44 Speaker 04 It's just you, you've anthropomorphized them, you've built them, I love these little guys now.
36:47 Speaker 05 They're, they're little guys and they have so many hands. Imagine them with tiny gloves. Anyway, yeah, he would chop off a part of the perimissium, he would just rotate it like 180 degrees. He would like, you know, I don't, you don't have to stitch it, you just put it back in the little cellular membrane, just whoops. You made it really good. That was good Foley right there. That sound that you made. And low and behold, the offspring of the like, kind of messed up, copy paste perimissium cells, they had the same deformity despite no direct changes to DNA. If you flip a perimissium cillium, their, their offspring have that same weird backward cilia. Yeah, it's wild, right? I, I, okay, I studied evolutionary biology in college. This is my undergrad
37:31 Speaker 05 degree and I had literally never heard about this. I, I learned this from, from like a friend at a punk show. I like made a joke about trying to reach something tall and I was like, if I do it long enough, I'll go full Lamarck. My, my kids are gonna have the longest arms. And she was actually like, I've got something funny about that. Shout out Annette. Anyway, how, why does this happen? Why is it that if you flip a part of a perimissium, it just like photocopies itself like that? DNA aside, we, we still don't really know. It's unclear. Oh, do you have something? Do you, do you know? Do you have a secret?
38:07 Speaker 04 I was just really hoping for an answer. No, that, that, that's, it's still a mystery.
38:11 Rachel Feltman? Yeah, that's probably why you didn't learn about it in college. Cause it's like kind of inconvenient, right? They're like, don't confuse the undergrads with that.
38:19 Speaker 04 That's such a weird asterisk to include.
38:21 Speaker 05 And I mean, there just hasn't, there's been, so there have been like a couple of follow-up studies, some in the seventies from different scientists, some in the nineties. This wasn't just like this one guy's one-off. They've replicated the findings. Like this does
38:32 Speaker 04 Oh.
38:33 Speaker 05 happen. I say that just because like when I was first, when I first heard about this, when I first saw the study, I was like, this Sonborn guy, he must just be like a real, a real wackadoodle.
38:41 Rachel Feltman? Are we really trusting the guy who is like, let's just put that thing down, flip it and reverse it?
38:48 Rachel Feltman? For fun.
38:49 Speaker 04 Wait a second.
38:50 Rachel Feltman? Say that again.
38:51 Speaker 05 Another fun fact about this guy is this is actually, he was the mentor to like James Watson, the person who went on to be like one of the co-discoverers or tri-co-discoverers of, of the shape of the DNA double helix. So like legitimate scientists, like very well respected in his field for a really long time, not just some wackadoodle, despite his like inclinations to flip it or reverse it. And there are like some vague ideas about what's happening here. So there might be some like post modification DNA transcription happening of these like little signal flags on the cell's surface of perimissiums. It might have something to do with little fragments of RNA that are in like the cytoplasm of the perimissium. So when it splits up,
39:35 Speaker 05 when it's doing its, its asexual reproduction, maybe bits of those RNA are then encoded. And when it's like regrowing its little cellular membrane, it's like, here's the new plan. But again, we really, we don't know. So please, somebody do the science here and tell me what's happening. Because if I think about this any longer, it's gonna unravel my entire understanding of biology. Okay, it's clear this doesn't happen in the same way in more complex organisms, but it's still.
40:02 Speaker 04 I was gonna say, it's intuitive, it's a little more intuitive in a single cell. Like I can imagine some, some mechanisms somewhere in the process of, of making one cell into two cells versus.
40:15 Rachel Feltman? This is, this is what we are now.
40:17 Speaker 04 Yeah, we're some, somewhere in the chain of community, I, I, what's it? The developmental biologist is fascinating to me. I think it's so wild. And so in all the complexity there, I'm like, I can imagine there. But yeah, of course, for a larger animal, I don't imagine. But that's, yeah.
40:33 Speaker 05 Yeah, I still think even at the smaller scale though, it's, it's bonkers. I mean, you can just slice and dice a perimissium and end up with like generations of the remix edit. And so. Those are single-celled organisms, but when you get into multicellular organisms, some studies in the 2010s of worms showed that you can still have like similar non-Mendelian inheritance patterns. So not necessarily just with like body plan, like they weren't, the head wasn't becoming the butt or whatever. But what they did find is that immune proteins that weren't necessarily coded in the worm's DNA, so like immune proteins to viruses introduced during a single worm's lifetime, could actually end up being inherited for like up to 100 generations.
41:16 Speaker 04 Wow.
41:17 Speaker 05 And it wasn't epigenetics, it wasn't any of that. It was just, again, because you might have like cellular cytoplasm in the, the sexual cell lineage that ends up holding on to a little bit of that, that immune RNA. And that when those cells then like divide and divide and divide and eventually you get a new worm, they're still carrying that kind of trace. And then that ends up getting replicated by all of the protein mechanisms that normally replicate RNA in the body. And then low and behold, you inherited an immune function that was not coded in your DNA.
41:49 Speaker 04 It's so cool. And I feel like I've been having this change in my mental perspective over the last handful of years, maybe more, that, right, DNA as like the code, like the immutable code versus DNA, something that physically exists, like in your, the cells in your body, where these oddities can happen is, is so fascinating.
42:12 Speaker 05 Yeah, it's not just, it's not like a computer program in a box. It's like a, a material that exists like in your body, in the world. And like, things can happen to it that then happen to the future also.
42:24 Speaker 04 Well, it's like, it's like a computer program in a physical computer that can get goofed up.
42:28 Speaker 05 Sure. No, I'm not there. I can't think of computer that way.
42:30 Speaker 04 Sorry.
42:33 Speaker 04 I'm like, I'm like, oh man, have you dealt with hardware? My God.
42:36 Speaker 05 No. And I actually think that that's the hardest part, right? Like roboticists, they're, they're always be trying to deal with hardware. But anyway, I just think between all this and epigenetics, I do think we got to retroactively give Lamarck some credit. I don't think he should exclusively be like a punchline among biologists. And I will stop doing my like arm stretch giraffe Lamarck joke maybe someday. Darwin may have won the unifying theory contest, but if you stretch science long enough, you might end up with a long, confusing list of exceptions to the rule.
43:07 Speaker 04 Nice.
43:07 Speaker 05 And that's my pun I'm ending on. That's my science pun.
43:11 Speaker 04 I have, so throughout this, I have been mulling this over and I think I actually do have, I figured it out.
43:18 Speaker 05 Incredible.
43:20 Speaker 04 La missy, la misdemeanor, la mark. There we go. That's what we were thinking about, right? Was we were trying to come up with the perfect pun for when, when we were talking about flipping and reversing it. Sorry, I wasn't listening to anything else. I was just mulling that over.
43:32 Speaker 05 I think you, you've solved multiple mysteries at once with that.
43:38 Speaker 05 Okay, we're going to take one more quick break and then we'll be back with one more fact.
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45:19 Rachel Feltman? Okay, we're back. And Tom, tell us why the rats do run this city.
45:27 Speaker 04 The rats, what's the, yeah.
45:28 Rachel Feltman? Yeah, it's the rats don't run this city.
45:30 Speaker 04 We don't run this city. The rats do.
45:32 Rachel Feltman? The rats do.
45:33 Speaker 04 Well, so, okay, no, I'm not gonna say that, but, but there are a lot of ways in which the rats have as much of a claim to the city as we do in a lot of ways. That's gonna be one of the things we're gonna talk about, but I'll say all of this comes from a fantastic paper, highly recommend the read, great overview, great diagrams and figures that show all their work called Computational Urban Ecology of New York City Rats. And then there's also a great article about this research from Denis Elise Bichard-Forssaiam that interviewed the authors of the paper and got some great insights and quotes. But before I dive in, we mentioned at the top, and this is just like a classic refrain we do on our podcast, but I was curious, what's y'all's familiarity with rats? Love them, hate them?
46:16 Rachel Feltman? I mean, as someone who's lived in the New York City area for more than a decade at this point, I'm all right with rats. Do I want one to show up unexpectedly and not leave? No. But, but like, when I see them out and about, I'm like, you have as much a right to be here as I do. That's how I feel about them.
46:39 Speaker 05 I respect them. I respect that they, their domain, they own this, they do own the streets, I think.
46:44 Rachel Feltman? And in the right context, they can be very cute.
46:46 Speaker 05 Well, okay, so I live in Baltimore now and not New York anymore. And we, Baltimore still has, we have many rats. And I'm growing a backyard garden and we have lots of tomatoes and the rats have figured out how to eat the tomatoes. And I think we have plenty to share. And I'm like, happy to like sacrifice a few to the cause of like a rat getting a healthy meal. But my, my partner is less convinced that that's fine. And so to try and convince him, I keep showing him little videos of how cute it can be when, like on YouTube, like rat eating tomato, cute. And then I'll just show it and be like, look, isn't this so nice?
47:23 Speaker 04 I like the idea that you're, you're picturing it as a healthy alternative to pizza. You're like, see, it's not processed.
47:29 Speaker 05 It eats the tomato or it eats the trash. Like, I, look, the, the backyard should not be food deserts for rats.
47:36 Speaker 04 I think there's a middle ground somewhere in there between we are actively growing crops to feed rats and also we can't share. Okay, great. This is great. I was hoping y'all would love rats, but I also personally, we've done many, many facts about how much we love rats on our podcast. We did a, we have an ongoing D and D series where we play rats that can Ratatouille humans as they do a heist and stuff like that.
47:59 Speaker 05 Wow.
47:59 Speaker 04 Love rats. And the story of rats and humans actually goes way, way back. And here we are specifically talking about the brown rats, Ratus norvegicus. This is your New York City subway rats, your pizza rats. But do y'all have any guess where they came from originally?
48:19 Speaker 05 Well, I know.
48:20 Speaker 04 Ratus norvegicus.
48:21 Speaker 05 I know they're called Norway rats, but that's because they were like first discovered or named as a species like at the ports in Norway or something. But I think they're originally from East Asia or Central Asia. No?
48:32 Speaker 04 You are absolutely correct. This is a classic science misnomer we are stuck with for the rest of our lives. Norvegicus does mean Norwegian, but we now believe that the brown rat came from Asia thousands of years ago, where they were already at that time commensal with humans, meaning like living alongside in this sort of like passive symbiosis. It's sort of like.
48:54 Speaker 05 Eating the tomatoes.
48:56 Speaker 04 Yes, yeah. Like flies alongside like an alligator. It's, you know, the alligators don't really care, but the flies might be able to benefit from like their leavings or stuff like that, right? Any, any food scraps, et cetera. Rat, the brown rats then expanded to Europe through trade before spreading across the whole world, thanks to this extremely effective ecological mechanism known as colonialism, if you've heard of that. And that's how rats made their way to New York City when the city itself was being built. It was, yeah, was, was being built. And so they have as much a right to your Bushwick apartment as you do. But as much as I'm joking here, studying animals in urban environments is fascinating.
49:37 Speaker 04 I, I think we often hear stories about how like urbanization has harmed species and that is of course totally valid. But the full picture also includes many ways that animals show how robust they are and how they adapt to cities in fascinating and unique ways. And. While that's not enough time evolutionarily for rats, city rats to have become their own species, there are papers that, there was a paper that came out a few years ago that showed that New York City rats are actually genetically different than the brown rats originally from Asia. But just as interesting, and actually much harder to figure out, is the question of how they are different behaviorally and socially. And so I love this line from
50:21 Speaker 04 the paper that goes, quote, "Here we address the gap by performing fieldwork in wild New York City (NYC) rats and introducing a computational toolkit for analysis of behavior and the environment." I love the, the, yes, you do need to clarify that that's what NYC stands for, I'm sure. But, so yeah, on the one hand, observing rats, like you all said at the start, seems really simple. We do it all the time, right? Every New Yorker has, has done this before, has, has observed rats. But the problem is that when we want to quantitatively analyze their behavior, that there was a ton that we take for granted that our eyes
51:01 Speaker 04 and our brains do, that computers cannot. Right? Even in sterile laboratory setting, measuring animal movements can be extremely tricky, let alone in New York City at night. It is like maybe one of the noisiest, worst conditions to try to collect data on the planet. I don't know if my microphone picked up construction, but like, that's, that's literally like what, what I'm talking about. And so being able to, and so, and so being able to, to parse the cacophony for what you're looking for is where that phrase "computational ecology" from the paper's title comes in. So, first off, they used thermal imaging, and they show some examples in the paper comparing like a regular camera to a thermal
51:45 Speaker 04 camera, and it is wild. It's putting on the glasses from They Live. It's just like, oh, there's rats. Oh, there's rats in that picture, it turns out.
51:51 Speaker 05 I watched They Live this past week. Wild.
51:53 Speaker 04 There you go.
51:54 Speaker 05 That fight scene that goes like four minutes too long. I don't know why they did that. Anyway, continue.
52:02 Speaker 04 Secondly, they used ultrasonic microphones, meaning above what our human ears can perceive, because that's often the frequency that rats talk at or make noise at. They do occasionally speak in our range of hearing, of course. There's a line in the paper that describes, quote, "vocalizations that had power in the human audible range." Parentheses, squeaks.
52:25 Speaker 05 Oh, it's adorable.
52:26 Speaker 04 It's so great. But more often than not, they are making ranges in a, they're making noises in a frequency we can't hear. So that's why the need for the ultrasonic microphones. And the last key to this computational ecology is, of course, the use of computation to be able to clean and parse and measure all this comically noisy data. And they do this specifically with AI models, but the good kind, the good kind. So for video, this means identifying and tagging the animals in these like countless hours of footage. Their movements, what is and isn't a rat. For the audio, this means being able to isolate their vocalizations
53:09 Speaker 04 separate from the guy's blaring Empire State of Mind 24/7. It gets extra hard when the rats are singing along too. You're like, oh, it's hard to, I can't tell which one's which. And then another thing I totally didn't consider with video is that unlike, again, the, if you imagine the sterile laboratory environment where maybe the, like, the camera's like top down, the room is perfectly square measured. Their cameras are often just mounted on a wall somewhere, looking across an area. And so they had to try to derive the 3D position of the rat so that they could judge its size compared to other rats, right? Because i- i- i- if, obviously, if it's closer, it looks bigger, but they wanted to be able to, yeah, compare sizes of rats. And then that's just like a, a problem I didn't even consider
53:54 Speaker 04 is, is, is tricky in this situation. And so, yeah, there is so much we take for granted with perceiving the world that requires a ton of computing work. And they pulled out-
54:05 Speaker 05 Could they, could they use the thermal camera redshift? Can they can they average all the colors of New York City's?
54:12 Speaker 04 What color is a is a is a New York City, right? Turns out it's cosmic latte. No, they they really, really pulled out all the stops for this. People in the computer vision or the VFX world might know this phrase, but they even used some Gaussian splatting to study the 3D environments. It is is wild. It's really cool. And I it's just, I just, I'm so glad that AI is only being used for academic purposes and not for underpinning, not the underpinning of a financial bubble or a tool for oligarchy and propaganda or an accelerator for environmental destruction. It's just, it's, it's just only used for.
54:44 Speaker 05 It's so great that people have been smart about AI. We we love our contemporary reality.
54:53 Speaker 05 We're having such a good time in our utopian future.
54:57 Speaker 04 I'm always saying, guys, we live in the best timeline. I'm always saying.
55:02 Speaker 05 Nothing has or will ever go wrong.
55:04 Speaker 04 I know, but I I do think it's good to parse apart the extremely vague and broad buzzword of AI.
55:15 Speaker 05 Totally, yeah.
55:15 Speaker 04 Because I I think in saying it's 100% bad, you do also, we don't want to throw, there's no nuance in there. And and and, yeah, there there it's, as a guy who studied artificial intelligence and computers and and stuff like that, years before ChatGPT was even a thing, it, I I have such a, just like, this isn't AI. AI can mean other things. So after all this analysis, what did they find? Well, they noticed quite a few fun behaviors. So firstly, smaller and younger rats tend to go exploring in groups. And when they do, they bumble around and move a lot more slowly.
55:55 Speaker 05 Roving teens.
55:56 Speaker 04 Yeah, I was gonna say, an astounding similarity to a human group known as NYU freshmen.
56:03 Speaker 05 Damn, it's so true.
56:04 Speaker 04 Whereas rats that went solo tended to be much quicker. And yeah, it, it, it also turns out that rats talk a lot more than we thought in the ultrasonic range, like they are constantly yapping. In groups alone, the paper describes some of the recordings they got as, quote, "Affiliative social interaction between two rats in the subway tracks, human audible vocalizations from an aggressive interaction between pairs of rats on the sidewalk and nearby trashcans, long-duration bouts of calls recorded from a rat foraging inside of a trash bag on the sidewalk." I love that one because it, it just, I, in my mind, it's them just like hooting and hollering while they're like Scrooge McDucking into garbage.
56:45 Speaker 05 I've been all those rats.
56:47 Speaker 04 I was gonna say, this last one, "human audible vocalizations from an aggressive interaction between a pair of rats in the park." Like, who amongst us has not been in an argument with their partner in the park and made human audible vocalizations?
56:58 Speaker 05 Yeah, Prospect Park is, is everyone's living room.
57:03 Speaker 04 And the rats too.
57:06 Speaker 05 The best place to get into a public argument.
57:08 Speaker 04 My absolute favorite anecdote was that they had a recording between two rats while an ambulance passed by, and instead of running away, or being quiet, or hiding, the rats increased their volume presumably to be heard over the siren. And that's just, that's, that's, that's a New York ad.
57:33 Rachel Feltman? That's beautiful.
57:34 Speaker 04 It's fascinating.
57:36 Speaker 05 They've adapted.
57:37 Speaker 04 Yeah, in many ways, yeah. Well, and so this is another interesting thing that they found is that typically rats in laboratory settings will make these very specific pitches of vocalizations when they're stressed out or in danger. It's at 22 kilohertz. But in the city, quote, "22 kilohertz vocalizations are used in diverse contexts, some of which are seemingly not aversive." And the reason this is very New York to me is, is this is basically the equivalence of being like, cars in laboratory settings only honk their horns when they're in extreme distress. And then in New York, cars honking their horns means the light has been green for five picoseconds and the guy hasn't moved. And as much as we're doing a lot of anthropomorphization,
58:22 Speaker 04 but this is something that has not been shown before in laboratory settings. There is this market difference in measurable behavior, which is really interesting. But of course, they did find similarities between rats in laboratory settings. And I think that's also interesting because it points to things that are ingrained versus things that are not. You're sort of getting at the nature versus nurture, right? And so, just like in the lab, even city rats tend to avoid open spaces. And that's both fascinating, but also gets to another bit of this study. Why this study is interesting is that it points to a way that we could learn to make
59:05 Speaker 04 sure that humans and rats can avoid each other in peace. Because unlike what, like we've joked about at the start, some New York officials say we don't need to go to war on rats. In fact, one New York exterminator was quoted in the SIAM article, and they said trying to kill rats in a building was basically just a waste of time, saying, quote, "It's like taking aspirin for a cancer." And so, if we can, for example, like figure out which of these ultrasonic pitches works to scare off rats, we could make a rat deterrent that is completely invisible to us. We could make, have a recording that is the rat equivalent of a person on the corner asking you to sign a petition. And so, the rats will just, "I'll take the long way. It's fine. I don't need to, I'll go around."
59:50 Speaker 04 Now, of course, the last thing I need to note here is I have been using phrases like "language" and "communicating." And I need to put a few quarters in the anthropomorphizing swear jar. I did, after all, frame this as rats are similar to humans. But of course, we don't know if we can use the phrase "language" here. That's a whole other can of worms, I think, we don't have time to get into. We do have some clues, though. So, for example, because of the physics of sounds, we know that ultrasonic vocalizations don't travel as far, right? That's why, like, you can hear a thumping bass from a car down the block. And so, that might point to how those types of calls are used, possibly in communication, possibly not.
1:00:34 Speaker 04 But there's definitely, what we can say is there's definitely a lot of noise going on. And as one of the authors of the paper told SIAM, quote, "Why would you vocalize if not to some end?" The fact that we don't understand that yet, this is one of the questions that really keeps me up. And so this paper is very much a starting point to hopefully further research into city rats. It shows that it is actually possible to study rats in the greatest and noisiest city on earth. And to me, it's one of the most exciting kinds of papers because it opens up like a million follow-up questions that we hopefully may be able to answer. Are rats using language?
1:01:17 Speaker 04 Would city rat language be different? Can a young upstart country rat really make it in the Big Apple on Broadway with just a duffel bag and a dream? Only future research can tell.
1:01:28 Speaker 05 Sex and the City Rats. I want the full, I want the full six seasons.
1:01:33 Speaker 04 We use the AI to categorize them into Miranda rats.
1:01:37 Rachel Feltman? Yeah, that's what I want the future of AI to be.
1:01:41 Speaker 05 Well, they are. I mean, there was like that whole thing about can this AI detection software translate whale speak into human language? I think like it wasn't 100% real, but what if it was? And what if we could understand what rats are screaming to each other in the dumpsters of New York City?
1:01:56 Rachel Feltman? Yeah, that would be cool. It's like when people are like, oh, I want and like AI caller that can translate my dog's barks. You already know what your dog means. We have no idea what the rats mean.
1:02:10 Speaker 05 I think that means we have to welcome them into our homes and we have to live with them for centuries and develop a distinct into, we have to use our own AI, which is our brains, our own intelligence to figure out.
1:02:22 Speaker 04 Is that just I?
1:02:23 Speaker 05 Yeah, just I. I personally will, will live with the rats, study them and get back to you on what they're saying.
1:02:30 Rachel Feltman? Okay, thank you. Wow, great fact. Tom, thanks so much for coming on. This was great. Would you remind our listeners where they can find you on the internet?
1:02:41 Speaker 04 Yes, this podcast, it's almost over, but we have another podcast you can listen to. It's called Let's Learn Everything. We have episodes on epigenetics, on rats, yeah. Episode 69 with Hank Green is one of my favorites that we've done. We have one with Tom Scott, but just search around for topics that interest you. And if you're in New York. Depending on when this comes out, if not, well, I'll keep doing them, but keep an eye out on 11/11, we have the next Our Findings Show, which is a science game show. We have the wonderful Mike Ragnetta, Taylor Moore, and Dr. Moya McTeer. It's gonna be a great
1:03:16 Rachel Feltman? We love Moya.
1:03:17 Speaker 04 Wonderful story time. It's just wonderful. It's so great. I'm so excited to have all those folks.
1:03:21 Rachel Feltman? And is that at Caveat?
1:03:22 Speaker 04 Yes, yes. You can find that. Thank you. I'm so bad at plugging this. You can find the info at ourfindingsshow.com.
1:03:30 Rachel Feltman? Perfect. The Weirdest Thing I Learned This Week is produced by all of our hosts, including me, Rachel Feltman, along with Jess Bodie, who also serves as our audio engineer and editor extraordinaire. Our theme music is by Billy Cadden. Our logo is by Katie Belloff. If you have questions, suggestions, or weird stories to share, tweet us at weirdest underscore thing. Thanks for listening, weirdos.
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Previous Ant Yogurt, Bunny Horns, Deadly Feather Fashion Next Check it out: 'Ask Us Anything' from Popular Science. On this episode, GOOSEBUMPS Page updated November 1, 2026 · transcript and summary are machine-generated