Learn about why we remember things in the opposite order as we see them and how spiders use atmospheric electricity to balloon through the air. You’ll also learn who actually ate the first oyster from author Cody Cassidy.
Learn about why we remember things in the opposite order as we see them and how spiders use atmospheric electricity to balloon through the air. You’ll also learn who actually ate the first oyster from author Cody Cassidy.
You Remember in the Opposite Order as You See by Reuben Westmaas
Ballooning spiders surf on electric fields by Cameron Duke
Additional resources from author Cody Cassidy:
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/who-ate-the-first-oyster-w-cody-cassidy
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 why we remember things in the opposite order as we see them, and how spiders use atmospheric electricity to balloon through the air. You'll also learn who actually ate the first oyster from author Cody Cassidy.
ASHLEY HAMER: Let's satisfy some curiosity. When you watch a movie for the first time, you take in every detail. The actors' expressions, their costumes, the particular way they deliver their lines. But when you talk about it afterward, you probably mention big stuff, like the overall plot and the relationships between the characters.
That may come down to a difference in the way we perceive and the way we remember. One happens in the opposite order from the other. Scientists know that the brain processes sensory information starting with the details, and working its way up to the big picture. They had assumed that memory worked the same way.
That's why the results of a 2017 study were so surprising. That assumption turned out to be wrong. Here's how they figured it out. For the experiment, the researchers had 12 participants judge the angles of two lines.
First, the participants were shown one line at a 50 degree angle for half a second. Then asked to position two dots to match the angle of the line they saw. They then did this 50 more times. Riveting, right?
Next they did the same thing 50 more times, only with a 53 degree angle. In their third and final task, they were shown both lines at once. And then they had to position two pairs of dots, one pair for each line.
The test doesn't sound too exciting for the participants, but the experimenters were absolutely thrilled. Here's why. The reason the participants repeated each test so many times was so the researchers could get a handle on how accurate they were at remembering the angle of each line individually. And, yeah, they weren't too accurate.
And when it came time to remember the angles of both lines, they were even worse. But here's the bizarre thing. Despite the fact that they got the angles of each line wrong, they were surprisingly accurate when it came to remembering the relationship between the two lines.
That suggests that the participants weren't remembering the smaller details of the individual angles. They were remembering the big picture relationship between them. For memory, the big picture is the primary experience.
The fact that you remember in the opposite order from how you perceive says important things about how reliable our memories are. It means that if you've already identified a larger pattern in a sequence of events, you're more likely to remember the specific details that support that larger pattern. And to forget the ones that don't.
This could be important for everything, from eyewitness testimony, to political elections. The big picture doesn't always match the small details. And that can be very hard to remember.
NATALIA REAGAN: I think this is fascinating.
ASHLEY HAMER: Yeah, I mean, the more I learn about the human brain, the more I realize I can't trust mine at all.
NATALIA REAGAN: I had this interesting conversation earlier this year about dreams and how the details of a dream, which can be all over the place and make no sense at all and, of course, your imagination and subconscious are on overdrive, don't really matter.
It's that feeling you have when you wake up. That you feel your hands were fish and your mom was a walrus, but you woke up feeling overjoyed. Doesn't necessarily mean you want your mom to be a walrus and you want fish for hands. But, yeah, there's something to be said for details versus the big picture.
ASHLEY HAMER: Totally.
NATALIA REAGAN: Remember Charlotte's Web, at the end of the book something strange happens. Charlotte's hatchlings climb to the top of a fence, produce little balloons made of spider silk, and fly away. Charlotte's Web might be fiction, but flying spiders are not.
In fact, many species of spiders are able to make balloons like this that can take them far away. The really amazing part, they're not using the wind, they're using electricity in the atmosphere. Yep, you heard me right.
Now, when you think of animals that fly, spiders don't ever make the short list. They never make the long list either, really. But Spider ballooning, as it's called, is much more common than you think.
In the 1930s researchers spent five years collecting insects from an airplane at altitude, and found 30 different spider species up there. One in 17 of their specimens were spiders. Some spiders have been found flying as high as four kilometers or two and 1/2 miles, and dispersing hundreds of kilometers from home.
Groups of migrating spiders are even known to drift through the air in packs called alarmingly, spider rain. To take to the skies, a spider will straighten its legs, point its abdomen up in the air, and let loose a triangular sail made of spider silk.
But how do they do it? Scientists have been wondering since at least the 17th century. By the early 19th century, there were two competing hypotheses. One said their silks catch the wind like a sail. The competing hypothesis suggested that spiders fly using electrostatic forces. That second idea might seem absurd if you didn't know this next part. Spiders can even balloon when there's no wind at all.
And guess what, a 2018 study demonstrated that spiders are, in fact, surfing on atmospheric electricity. This is possible because atmospheric electricity fluctuates with the weather. And it's also easily disturbed by objects, like, say, a tree branch or a fence pole.
These objects can generate a tiny electric field with an opposite charge to that of the air. That difference in charge is strong enough to lift a tiny spider up, up, and away.
To determine this, researchers placed spiders in boxes that were shielded from the wind, then messed with the electric field in the box. They found that when the air was charged enough, the spiders would raise their abdomens as if trying to balloon. Some of them even took off.
And when the researchers turned off the electricity, they plummeted to the ground. Oh, it's kind of sad. How do they to take off? It's because spiders can sense electric fields through little leg hairs called trichobothria. That means for a spider the cue to fly is literally its spidey senses tingling.
ASHLEY HAMER: Have you ever eaten an oyster or drunk a beer and thought, how did the first person actually decide to consume this? There are a lot of foods and beverages that are kind of nasty the first time you try them. And the ancient humans who tried them first, did not have some food snob to assure them that it was an acquired taste.
So how did they end up doing it? Today's guest has the answer. Cody Cassidy is the author of the new book, Who Ate the First Oyster? The Extraordinary People Behind the Greatest Firsts in History.
The book uncovers the geniuses behind many of history's forgotten innovations and world turning inventions. From the person who wore the first pants, to the Stone Age physician who performed the first surgery. Our question for him today was pretty obvious, who did eat the first oyster?
CODY CASSIDY: So, yeah, it sounds like a joke of a question but it surprisingly does have an answer. The archeologists have found the oldest eaten shellfish they were around 164,000 years old. This is in the bottom of South Africa.
And we think the first oyster eater was probably inspired by another animal eating oysters. A few other animals eat them, so she was probably given a little bit of hope that the slimy creature wouldn't kill her.
But I think, probably even more interestingly, is that there were so many oysters there that archeologists believe she actually learned how to gather them efficiently, which meant she was able to predict the tides. And she probably did so by recognizing that the full and new moon represents these super low tides. So she was not only a bold eater, she was a bit of a astronomer as well.
SPEAKER: How long are we talking about because, first of all, I'm struck by you keep saying she. So how do we even know it was not a guy that did it?
CODY CASSIDY: So I like-- this is obviously long before writing. But the purpose of the book was to give these people, who really existed, personalities. And I think a big part of us identifying them as individuals is giving them a name. So I would give them a name usually inspired by some fact about them.
We, of course, don't know for sure about gender some of these were, but I would speculate based on evidence. And in the case of the oyster gal, in hunter, gatherer communities, like she was in, women were more predominantly gather staples and men usually go after food that sort of run, flies, or swims away. And so oysters are generally gathered by women in hunter, gatherer communities.
ASHLEY HAMER: One question that I really have is for someone to be the first person to eat something, like eating an oyster or tasting beer, I mean, sometimes this stuff tastes like poison or looks really gross, or actually is poison. Like, how does someone decide that this is delicious and I'm going to do it again?
CODY CASSIDY: I think, well, the survivalists have a strategy. They they'll eat-- that oyster gal and other first eaters probably practices, you eat a little small piece, and you eat it on an empty stomach. And then if you feel poorly, you start trying to make yourself throw up right away.
So oyster gal was rewarded with a tasty food, but there's a lot of others who wouldn't have been. Like wild almonds, for example, have cyanide in them. And it wasn't until somewhat recently, relatively recently that occasionally the almonds will have a genetic mutation that they don't produce cyanide.
So the only explanation of how we had these safe almonds is that people just kept trying them and trying them until they found the rare almond that didn't have the poison. So, yeah, history is, I think, full of a lot of brave eaters or hungry people or both.
ASHLEY HAMER: I, for one, will never look at a bowl of mixed nuts the same way again. That was Cody Cassidy, author of Who Ate the First Oyster? The Extraordinary People Behind the Greatest Firsts in History. You can find a link to pick it up in today's show notes. And he'll be back tomorrow to talk about the dirty, smelly history of soap.
NATALIA REAGAN: Let's recap today's takeaways. So we learned that people's memories may be better at remembering the bigger picture over minute details, which can be used when studying how eyewitnesses detail their accounts and, well, how elections play out. I think a lot of people go with patterns rather than realizing the details of their choices.
ASHLEY HAMER: Yeah. When you're learning about something, you use all the details to make a judgment. And then it's that judgment that sticks with you. Our brains are always looking for shortcuts. And so if we can just remember the general gist instead of all the tiny details, it's a lot easier.
And we learned that spiders can balloon their way through the skies using atmospheric electricity. And sometimes they reach altitudes of four kilometers. And some of these spiders fly in clusters that are referred to as spider rain.
NATALIA REAGAN: Now, spider rain is very 2020. I feel like, you know what? We've got fire NATOs, hurricanes, pandemics, bring on the spider rain.
ASHLEY HAMER: Just bring on the spider rain. It's better than hordes of locusts, maybe? I don't know.
NATALIA REAGAN: I mean, it depends on what kind of spiders we're talking about. We're talking black widows, we're talking-- I live in a place filled with daddy longlegs, and I just let them thrive here because they're affable, they don't hurt me. They just kill the fly population, and that's OK with me.
ASHLEY HAMER: Yeah, we all got to live together.
NATALIA REAGAN: We also learned that the first person brave enough to eat oysters was in South Africa, some 163,000 years ago. And was most likely female, given the fact that many modern day hunter, gatherer groups, the women are the ones gathering in the staples. And, yeah, again, she must have been pretty brave too because there's no way of really knowing that the oyster couldn't have killed her.
ASHLEY HAMER: This interview was a big day for me because that's one of those questions that I always have whenever I eat something gross. It's like, how did someone decide this was good and worth trying again?
NATALIA REAGAN: A good friend of mine is a cheesemonger. And she actually loves telling stories about cheese. And it is a common thing in the cheese world where they usually end a story with, and they ate it anyways. Because it's like, a shepherd left a canister or whatever, a carafe of milk in a cave for two years, they come back, they're starving, it is covered in God knows what mold, and they ate it anyways.
ASHLEY HAMER: I see, so I'm not a disgusting person. I just have connection with my heritage.
NATALIA REAGAN: Exactly. What you are is a brave lady, Ashley.
ASHLEY HAMER: Yeah.
NATALIA REAGAN: Today's stories were written by Ruben Westmeath and Cameron Duke. And edited by Ashley Hamer who's the Managing Editor for Curiosity Daily.
ASHLEY HAMER: Scriptwriting was by Natalia Reagan and Sonia Hodgen. Today's episode was edited by Natalia Reagan. And our producer is Cody Gough.
NATALIA REAGAN: Be sure to avoid the spider rain. And join us again tomorrow to learn something new in just a few minutes.
ASHLEY HAMER: And until then, stay curious.
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