Today you’ll learn about why some people are more popular with mosquitoes than others, what tickling rats tells us about being human, and how a recent discovery of ancient statues re-writes what we believed about historical Tuscany.
Today you’ll learn about why some people are more popular with mosquitoes than others, what tickling rats tells us about being human, and how a recent discovery of ancient statues re-writes what we believed about historical Tuscany.
Mosquito Magnets
Laughing Rats
Roman Relics
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/mosquito-magnets-laughing-rats-roman-relics
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about why some people are more popular with mosquitoes than others, what tickling rats tells us about being human, and how a recent discovery of ancient statues re-writes what we believed about historical Tuscany.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
CALLI: If you’ve ever been camping, you might hear some of your friends complaining about being targeted by mosquitoes nonstop. You might just think that it’s a luck of the draw situation, some people being more attractive to mosquitoes, BUT there is actually science behind why some are mosquito magnets!
NATE: K, I recently went on a trip to Florida and I came back with my ankles and legs eaten alive. The mosquitoes RAVAGED me. So, what is it about me that mosquitoes love so much?
CALLI: So, first off, my condolences. To understand what makes someone a mosquito magnet, you need to know that most mosquitoes require a certain protein from your blood in order to make eggs. Any time you’re stung by a mosquito, it’s a female mosquito, since the males only feed on plant nectar. Because of how important blood is to the female mosquito, she’s got a grocery list of qualities she looks for in a potential donor.
NATE: Like what?
CALLI: For starters, your breath. Mosquitos are very sensitive to carbon dioxide and can sense it from many, many meters away with receptor cells on their antennae and legs. So they sense the levels of carbon dioxide in your breath and can figure out who’s the better meal based on that.
NATE: Wait. Mosquitos judge how tasty we are by how our breath smells?
CALLI: Yeah! Mosquitos can also smell lactic acid, ammonia, and fatty acids quite effectively. But that’s the simple part. The part that’s a bit more complicated is that the way our bodies give off carbon dioxide is related to our metabolic rates, or the amount of energy we use while at rest. Even though most of our metabolisms are genetic, it can also be increased through physical activity. That’s usually why mosquitoes are attracted to people who just took part in something strenuous, because we’re putting out more carbon dioxide. They loooove when our metabolism is working hard!
NATE: Okay, but when I was in Florida, I wasn’t exactly working out. I was with some friends, we had some food, some people were drinking a little… it wasn’t anything strenuous.
CALLI: Okay, well, if your friends’ drinks were alcoholic, that could be another reason. Alcohol increases the metabolic rate. And one of the only other things that increases metabolism, which is being pregnant, wouldn’t apply to you, which leaves us with one other part of the mosquitos sensing blood through smell: body odor.
NATE: You’re telling me that mosquitoes… think B.O…. smells tasty?
CALLI: Yeah! Some species of Anopheles mosquitoes are known to especially love foot odor and can start attacking your feet while you’re asleep.
NATE: Well, that’s not terrifying at all. Okay, but it can’t just be scent, right?
CALLI: You’re right, there’s more! Mosquitoes can ALSO rely on visual cues. During the day, they fly close to the ground and view potential targets as contrasting shapes against the horizon. Dark colors are what stand out; light colors blend into the horizon. So if you go camping, maybe leave the black t-shirts at home and bring out some khakis instead.
NATE: You’re messing with me. You just want me to look like a dork when I go camping.
CALLI: You look like a dork anyway, Nate. Especially because I remember seeing you after you came back from Florida - you got stung ONCE and are exaggerating the heck out of your story. That’s actually something researchers want us to heed when thinking of ourselves as mosquito magnets: some humans have a natural psychological reaction to mosquitoes that triggers our fight-or-flight instincts.
NATE: Calli, I’m not making it up! I was bit way more than once! They attacked me viciously.
CALLI: Oh! Okay, fine, 100%. I can’t say for sure if there were more than one mosquito in Florida, but that day, you got stung, felt it, and started screaming that you were under attack. That’s actually pretty normal, and nothing to be ashamed of! It affects roughly half of people, with the other half not really noticing the buzz or the sting, or even the welt left behind until much later.
NATE: *sigh* Okay, Calli. But what you’re saying anyway is that mosquito magnets do exist, right? And they’re attracted to sweaty people with smelly breath, smelly body odor, who have possibly been drinking?
CALLI: Exactly. And for the record, you smell okay, so I think you might just think you’re a mosquito magnet when you’re actually just a big baby.
NATE: Oh cool. Great. Thank you, that’s very reassuring.
[SFX: WHOOSH]
NATE: I’m gonna cut right to the chase here, and tell you that today, we’re talking about what scientific research tells us about tickling rats.
CALLI: Tickling… rats? You mean like snitches, or…?
NATE: No, no, no. I mean rats. Actual rats. The mammals. There was an experiment in 1999 where a scientist named Jaak Panksepp put on his lab coat, went into his lab, and tickled a rat. With his finger. And you wanna know something else? This was groundbreaking scientific research. Seriously.
CALLI: If that’s groundbreaking research, then call me Albert Einstein for all the times I’ve scratched my cats’ bellies. I’ve even had pet rats and I’ve done that. So, what was so groundbreaking about this?
NATE: It sounds crazy, but this research was inspired by the discovery that rats are a lot like primates: they scream when scared, laugh when playing, and even make noises during sexual intercourse. All of this is silent to the human ears, happening ultrasonically, and we didn’t discover this until the 1960s. What Dr. Panksepp wanted to do was find out more. So he started playing with the rats.
CALLI: Further proof that science can be a lot of fun.
NATE: Especially for the rats: it didn’t take long for him to discover a few interesting things. First, just like humans, rats love laughing. Unlike humans, they also like being tickled, which feeds into the biggest discovery: when rats are feeling playful, they like to wrestle each other. He discovered this when observing rats’ natural tendency to “pin,” where one rat is on its back while the other is hovered above in a “dominant” pose.
CALLI: That’s interesting. But why is this groundbreaking research and not, like, the subject of a YouTube series I would watch right now?
NATE: Because it’s proof that play, laughter, and joy are truly ancient behaviors in mammals, evolutionarily speaking. We long thought that behavior like this was limited to humans and primates, but now… welcome to the party, rats. And it’s a good party to be at, because it’s a playful one. And being playful, believe it or not, is actually important for our development.
CALLI: This is exciting news for me, because I too like to play. Why is play so important?
NATE: From an early age, being playful contributes to motor skills and how our muscles develop. That’s why physical play is helpful, but it goes deeper socially speaking. We’ve long known that socializing helps humans become stronger intellectually; turns out, it’s the same for rats. And much like when humans are cooped up inside too long, getting bored and restless, the same behavior can be seen in rats.
CALLI: So, rats experienced the lockdown blues like we did, huh?
NATE: Exactly. And there are serious consequences for adolescent rats who don’t socialize properly: their orbitofrontal and medial prefrontal cortices won’t develop properly in the brain, so they can be more prone to exhibit aggressive and antisocial behavior.
CALLI: Back to the physical aspect for a second, is this why rats like to wrestle?
NATE: Yeah. So-called “rough-and-tumble play” is important for human children to learn their own tolerances for pain, as well as to learn the concept of restraint, so as not to hurt others. This is true for rats, too. Panksepp noticed that rats injured by a friend are less likely to play with that friend again, for instance.
CALLI: Interesting. So what were these little rat wrestling matches like? Did Panksepp give the rats little luchador masks and put them in a ring?
NATE: Unfortunately, no. He just watched the rats wrestle. How it went down was a dominant rat would pin a subordinate rat roughly 70 percent of the time. Usually, the dominant rat was about 10 percent bigger, but weirdly, this wasn’t always a factor. But even when they pinned another rat, the dominant rats would get into positions that they had to have known would make it easy for the other rat to flip them over.
CALLI: What? Why would they do that?
NATE: Because of something called “self-handicapping,” which is inventing a weakness you know will be exploited. But this is all in the name of fun and trust with the other rat, and Panksepp believes it’s related to reciprocity: the idea that the other rat should have fun during play, too.
CALLI: That’s surprisingly complex thinking for a rat. It almost sounds like a consideration of ethics during play, which might even be more complex than it is for human children.
NATE: Actually, it’s exactly how human children develop, too, and may have emerged as early on as during the evolution of our earliest ancestors. Children start to construct a sense of morality and fairness through shared games, and around the ages of 5 to 8, learn to play together. They can notice violations of a rule structure, even before being able to explicitly state the rules of a game. Just like the rats.
CALLI: Wow. So what you’re saying is that… we’re more like rats than we thought?
NATE: Sure, but don’t take that as a bad thing. The way the researchers put it is a positive spin on that idea: “Studying the play behavior of rats, and even tickling them in the name of science, shows us what it means to be human.”
[SFX: WHOOSH]
CALLI: So Nate, I know that you are the resident Ancient Rome expert on this show, and I’m hoping you’ll be able to help me talk about a recent discovery in Italy of some old Roman statues. Apparently they completely change everything we know about Ancient Rome!
NATE: You are absolutely correct and you’ve chosen a good partner for this discussion, Calli, because I know literally everything there is to know about Roman history. Uh, I do like Roman history, I would not say I’m an expert. I like it, I’ve especially done a lot of art history classes but this is new to me I’ve only heard a little bit of this story, though, so tell me a little more and I’ll see what I can contribute.
CALLI: Okay, awesome, thank you. So archaeologists based out of Italy recently found 24 beautifully preserved bronze statues in Tuscany, which is a region of Italy. The statues were found beneath the muddy ruins of The Great Bath Sanctuary of San Casciano, and depict Greco-Roman gods like Hygieia and Apollo, with Etruscan and Roman languages scripted on them. What makes this a big deal is that the statues were dated to have come from somewhere between the 2nd century BC and 1st century AD, which was a period of “great transformation in ancient Tuscany.” Long story short: it seems like a huge deal to me, but I don’t know much about ancient Tuscany!
NATE: Okay so, they had both Etruscan AND Roman script on them? That’s actually a huge deal. Back in the 2nd Century BC, Tuscany wasn’t Tuscany: it was Etruria, which is where the Etruscan language comes from. Etruria was pretty much the first “superpower” of Europe, and developed most of the first cities in the Western Mediterranean - including some cities like Florence and Pisa, which still exist today!
CALLI: That’s incredible. I’ve never heard of Etruria before. But that doesn’t answer why it’s so wild that both Etruscan and Roman were on these statues.
NATE: Well, there’s a reason why you haven’t heard of Etruria. It’s because sometime around 500 BC, they were attacked by Ancient Rome. It was modern Rome at the time, now it’s Ancient Rome. This kicked off a chain of events that led to Rome completely destroying the Etruscan empire over 200 years later in 265 BC. Etruscans were assimilated into Ancient Roman society, and the rest is history. THAT’S why it’s such a big deal: if these statues are dated back to when Rome and Etruria were at war, it paints a completely different picture of Rome and Etruria’s relationship.
CALLI: So, get a load of this: the statues had a little water damage, too. Not from thousands of years of sitting around, but damage that came from the era they were used in. So the researchers think these statues were used in a religious ceremony where they were immersed in warm waters while everybody prayed.
NATE: Alright, I actually don’t think I’ve ever heard of this ritual before. Why do you think they did that?
CALLI: They believed that whatever you give to the water will hopefully give you something equally good in return. So if you give the water something that looks like a god - the water might give you a better life in return.
NATE: That’s a beautiful idea. So let me see if I have this right: there was a ceremony where people submerged statues for the gods during a time when Etruria and Rome were at war - but the statues had Etruscan and Roman script on them. Knowing what we know about Etruria, that creates a bit of a conundrum, doesn’t it?
CALLI: Well, the Great Bath Sanctuary, where these statues were found, was apparently a sort of neutral ground during the wars. It was a "unique multicultural and multilingual haven of peace,” and because of these statues, researchers now believe that Etruscan and Roman families came together to pray.
NATE: You know what this kinda reminds me of? The Christmas Truce of 1914. When Christmas Day arrived during World War I, almost every force along the Western Front called a ceasefire to share a Christmas dinner together. German, French, British, everyone stopped fighting for a moment and just… got along.
CALLI: Yeah. And in both situations, we know the aftermath. But it’s really nice to know that in times of uncertainty, people can put aside their differences and just appreciate the little things.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Been stung by more mosquitoes than usual lately? New research suggests that you might be emitting the scents that mosquitoes crave out of their potential targets: bad breath, bad body odor, alcohol, or just plain old sweat. Rest assured, though: other research says it’s just as likely you’re imagining mosquitoes following you around, so you might not need to take an acid bath for that B.O. just yet!
NATE: Tickling rats: a scientific breakthrough? You bet! It turns out that rats are one of the few creatures aside from humans known to make explicit noises in experiences of joy, and even laugh when you tickle them. That’s because rats, like humans, still maintain the ancient evolutionary need for playing around as a form of development. This research, amazingly, teaches us more about being human than we ever thought possible!
CALLI: They say that history is written by the victors, but a recent discovery out of Tuscany shows that history isn’t written, merely forgotten. A treasure trove of statues have been found dating back to the 2nd century BC, revealing that the warring countries of Etruria and Rome actually got together for religious ceremonies during times of uncertainty. This discovery completely changes what we know about the time period - and shows that even enemies can come together for a united cause.