Learn how the mathematical mistake of exponential growth bias makes people underestimate the spread of COVID-19, how crocodiles have survived since the dinosaurs, and how puns activate both sides of the brain.
Learn how the mathematical mistake of exponential growth bias makes people underestimate the spread of COVID-19, how crocodiles have survived since the dinosaurs, and how puns activate both sides of the brain.
"Exponential growth bias" can make people underestimate COVID-19 by Steffie Drucker
Crocodiles Are Prehistoric Monsters Who Survived The Dinosaur's Extinction by Reuben Westmaas
“Getting” Puns Means Both Sides of Your Brain Are Working Together by Reuben Westmaas
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/the-math-bias-that-makes-you-misjudge-covid-19
ASHLEY HAMER: Hi, you're about to get smarter in just a few minutes with Curiosity Daily from curiosity.com. I'm Ashley Hamer.
NATALIA REAGAN: And I'm Natalia Reagan. Today, you'll learn how something called the exponential growth bias makes people underestimate the spread of COVID 19. How crocodiles have survived since the dinosaurs? And how puns activate both sides of the brain?
ASHLEY HAMER: Let's activate some curiosity. Woohoo. What if I told you that understanding math could save lives? When it comes to stopping the spread of COVID 19, it's true.
Coronavirus cases grow in a different way than we're used to seeing things growing. And a better understanding of the math at play, can lead to more support for things like social distancing and wearing masks. The mathematical principle I'm talking about is called "exponential growth."
Here's an example of exponential growth, imagine a bank offered a deal that would double your money every day. So, you invest $1 to open an account. How soon would you become a billionaire? Five years? 10 years?
You may be surprised to learn that the answer is 31 days. Just about one month. You're not alone if your guess was totally off.
In fact, so many people underestimate how quickly the value increases, that scientists have coined a phrase for it, exponential growth bias. Money can feel a little abstract. So let's try another example. This one was featured on Radiolab at the start of the pandemic.
Imagine, if you had a 10-foot by 10-foot room, that's 3 meters by 3 meters, like a large bathroom. What if you doubled its size every day? In five days, it would be the size of a house.
Around the second week, it's the size of a city block. And after a month, it's the size of New Jersey, in just one month. That's the power of exponential growth.
We're not used to this kind of incredible growth. You probably put about the same amount in your bank account every month. When people add on to a room, they do it by a few feet at a time, that's called linear growth, and it's much, much slower.
That's what's so tricky about COVID 19. The virus's super rapid spread is exactly why it was declared a pandemic, and why World leaders called for a hard lockdown. Without any interventions, experts say the number of new cases doubles every three to four days. That means it would take just 90 days to infect the entire planet. 7.8 billion people.
But a study in March found that, on average, Americans misperceive the virus's exponential growth for linear growth. Other studies have found that this kind of misperception can lead to less hand-washing and social distancing. The good news is that this particular bias is fairly easy to overcome.
In that March study, the scientists just told one group that a lot of people make this mistake and reminded them that coronavirus cases tend to double every few days. In the end, that group was more likely to support social distancing recommendations than a control group that didn't get that reminder. So, here's your reminder, who knew that understanding math could save lives?
NATALIA REAGAN: Now, some might say crocodiles basically look like living dinosaurs. And you'd be forgiven for thinking that's exactly what they are. But they're not.
Their lineage never died out. They're still around. Just as scaly and scary as ever. But they did change. And thanks to fossil evidence, we know that modern crocs have nothing on their ancient predecessors.
We know this because a few years ago, scientists put together a set of bones from one of crocodile's earliest known ancestors. The species is known as Razanandrongobe. And it shows that ancestors of crocodiles, called notosuchians, are much older than scientists previously thought.
Raz, can I call her Raz? I'm going to call her Raz. Raz is an example of a ghost lineage.
An evolutionary line that we've inferred was there, but never have discovered. She's no less than 163 million years old, which is 42 million years older than the next oldest notosuchian that we've discovered. And compared to her descendants, she's a much different animal.
First, her teeth. Raz predated Tyrannosaurus Rex by 100 million years, but her teeth wouldn't have looked out of place in a T-Rex mouth. Then there are her legs, which are long enough to give her a body that's more like a bear or a dog than a modern crocodile. Painting quite a picture, right? What might be the most amazing of all is her armor, which scientists think was banded like an armadillos.
Oh, and some estimates place her upwards of 39 feet or 12 meters long. Bigger than a city bus, which would make her the biggest notosuchian of all time. Basically, Raz look like she walked right out of a Godzilla movie. She was almost certainly the apex predator of her territory and likely feasted on dinosaurs at every opportunity. Yikes.
Though Raz was much different from modern crocodiles, it only took a few dozen million years for the basic body plan of a croc to be standardized. They stayed giant for a long time though. So, how have crocodiles been able to survive on the planet for so long? What gives them their stubborn longevity?
The truth is, it's hard to say. Seeing as how they've basically gone unchanged since dinosaurs walk the Earth, they've clearly got their niche carved out. And their incredible resilience had to have helped too.
Crocs regularly survive lost limbs and other severe wounds. But the real key is probably their hunting habits. Crocodiles and their relatives wait in water until their thirsty prey gets too close, then they strike.
So as long as crocodiles can blend into a muddy pool, and as long as animals need water to drink, they'll probably be just fine.
ASHLEY HAMER: Unless Raz is still around.
NATALIA REAGAN: Yeah.
ASHLEY HAMER: And then a bus-sized crocodile with long legs comes and just swallows them in one gulp.
NATALIA REAGAN: Yeah, the long-limbed crocodile is a very funny look for me. You know, I just think of the female gremlin from the Gremlin movies, you know? But, Hi, I'm Raz. I'm here to eat your whole family.
ASHLEY HAMER: Cody is on paternity leave, and I know we all miss him. So, to satisfy our Cody fix, we're going to play a throwback Thursday Cody special. It's about puns. Because if we're going to do a throwback Cody story, it has to be about puns. Enjoy.
CODY GOUGH: How much do you love puns?
ASHLEY HAMER: Working at curiosity has really increased my love of puns. I did not use to like them, but they're really becoming a part of me.
CODY GOUGH: Well, a recent study found that both sides of your brain work together to help you understand puns. So I think that they are a genius device. But let's back up for a second.
The whole left brain versus right brain theory thing has been pretty much debunked, right? It's not like the left brain is the organized logical side, and the right brain is the creative emotional side. That's not science.
But research has indicated that some skills may tend to live more in one side than the other. Like language, sometimes prefers one side, for example, and a lot of people, it's the left brain. Although, in many people, language is in the right brain.
ASHLEY HAMER: Actually, a lot of times if your left handed or right handed, that can change what side of your brain certain things are on.
CODY GOUGH: Right, exactly. There you go. So there can be differences.
And there can be preferences for one side or the other in certain skills. But researchers took some puns, and showed them to participants in this study, in the visual field of only one eye. That's because, and I did not know this, if a joke lands in the right eye, it gets to the left brain first and vice versa.
ASHLEY HAMER: It's wild.
CODY GOUGH: Yeah. When the joke hit the left brain first, people reacted to the joke faster, which suggests that the left side of the brain is better at joke processing than the right side. But get this, the right side was the one that actually found the puns funny.
The idea here is that the left side has powerful language abilities, so it's better able to actually understand the joke. And the right side is the one that comes in with the alternative interpretation of the words that lends the joke gets laughs. This research backed up previous studies that showed that people who have damage in their right brain, can sometimes understand a joke's meaning, but they don't think they're funny anymore.
And hey, if comedy can't be found in the brain, then maybe it lives in the humerus.
ASHLEY HAMER: Oh, that wasn't your joke. That was Reuben Westmaas's joke.
CODY GOUGH: That was Reuben's joke.
ASHLEY HAMER: We have to give credit where credit is due.
CODY GOUGH: Ripped that off blatantly. This is why I'm not in comedy.
ASHLEY HAMER: You are in comedy.
[BOTH LAUGHS]
NATALIA REAGAN: Now, let's do a quick recap of what we learned today. We learned that understanding the mathematic principle exponential growth can help us avoid experiencing exponential growth bias, which could lead us to miscalculating the threat of a global pandemic, like COVID 19, and not taking as many precautions as we should because we all should be taking a lot of precautions. Again, it makes me think of the bubonic plague. Listen to Tuesday's show, it's pretty darn interesting.
ASHLEY HAMER: You hear about exponential growth bias a lot in terms of investing. Like finance people will always make you feel bad about not starting your 401K earlier than you did. Just waiting a few years will make you lose $100,000 or something.
And you're always like, I don't know. It always makes me feel guilty. And making me feel guilty is not a way to get me to do anything. But I understand that exponential growth is very large, and I should pay attention.
NATALIA REAGAN: Well, I think the threat of feeling guilty is one thing. But like guilty and you could die,
ASHLEY HAMER: Yeah.
NATALIA REAGAN: --is another thing. So, you know, but you did. It was funny when you were doing the thing on exponential growth. I thought, I need to put more money into my savings account.
ASHLEY HAMER: Right.
NATALIA REAGAN: But I also think of contact tracing when I think of exponential growth bias and things of that sort. Because living in New York City, I have a lot of ER doctor friends and those that are studying contact tracing, specifically. Because contact tracing is basically finding patient zero in an area, and just understanding who they had contact with, and basically tracing it.
And how hard it is to do it in places-- urban places like New York City? Because I remember, going into the doctor's office on March 12, and I remember it was right when COVID was just blowing up, and the next day, basically, we're on lockdown. And I was asked by the receptionist at this doctor's office, have you been in contact with anybody who's traveled in the past two weeks?
And I was like, I was just at Union Square in rush hour.
ASHLEY HAMER: Seriously?
NATALIA REAGAN: Yeah, I'm sure. Right? So it's hard to know how much we come into contact with people, and how quick something could spread. So I think it's important to err on the side of caution when it comes to exponential growth because a global pandemic is nothing to mess with.
ASHLEY HAMER: Definitely. And we learned that modern day crocodiles had a pretty terrifying ancestor, known as Razanandrongobe. How do you like that tongue twister?
This animal was bigger than a city bus. And we also learned that crocs' ability to survive the Mesozoic extinction makes modern-day crocodiles even more impressive.
NATALIA REAGAN: I think so. And I always have to correct folks when they say, crocodilians are like dinosaurs. Because they are to an extent, but they're very, very different.
And chickens, which, we all know about Carol and Janette, my house dinosaurs, they are actually more closely related to dinosaurs than modern-day crocodiles are. So that right there, I think is a very cool fact.
ASHLEY HAMER: It is. I love to look at like a little songbird's feet because that's the clue. It's like, oh, those are dinosaur feet.
NATALIA REAGAN: Their talons.
ASHLEY HAMER: If they were bigger, they could completely just kill me.
NATALIA REAGAN: This is true. Finally, we entered the pun zone. And Cody taught us that while the left side of the brain can understand a pun quicker.
It's the right side of the brain that has the ability to figure out the wordplay and find it funny. Ashley, I "lobe" this story. I blacked that one out.
So, yeah. Cody has a really cool method of hiding jokes from Ashley. And I tried it this time.
ASHLEY HAMER: Yeah, it's hilarious. He basically just highlights the joke in black, so that I can't see it. And then, if he highlights it on his doc, he can suddenly see it. And so I laugh authentically or groan authentically, more often the second.
NATALIA REAGAN: I think you're probably going to do the same with me, honestly.
[BOTH LAUGHS]
We have the same pun-centered jokes, dad jokes, really, honestly.
ASHLEY HAMER: Yeah, fantastic.
NATALIA REAGAN: Today's stories were written by Steffie Drucker and Reuben Westmaas. And edited by Ashley Hamer, who's the managing editor for Curiosity Daily.
ASHLEY HAMER: Scriptwriting was by Natalia Reagan and Sonia Hodgson. Today's episode was edited by Natalia Reagan and our producer is Cody Gough.
NATALIA REAGAN: Stay away from those murky pools, and join us again tomorrow to learn something new in just a few minutes.
ASHLEY HAMER: And until then, stay curious.