Today, you’ll learn about how humans could potentially evolve to be venomous, the challenges of repurposing used electric car batteries, and how people who hate magic are more likely to have certain socially aversive traits, like needing to control social situations.
The good and the bad side of snake venom.
A new era for batteries.
Who hates magic?!
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/human-venom-car-battery-blues-magic-and-personalities
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 how humans could potentially evolve to be venomous, the challenges of repurposing used electric car batteries, and how people who hate magic are more likely to have certain socially aversive traits, like needing to control social situations.
CALLI: Without further adieu, let’s satisfy some curiosity!
[SFX: Whoosh]
CALLI: Man I can’t wait to have my own venom.
NATE: Uhhh what?
CALLI: Turns out it’s possible for humans to become venomous just like other animals.
NATE: And here I thought I’d never have anything in common with a rattlesnake.
CALLI: Your knees do kind of rattle when you stand up.
NATE: Ugh I’m getting older by the day. Thanks for reminding me. So wait, how would humans be able to develop venom?
CALLI: It all comes down to the genes in our salivary glands. Biologists have long known that oral venom glands are just modified from typical salivary ones. But there’s new evidence that shows a complex system of molecular mechanics at work behind that change.
NATE: Ooo molecular mechanics are my favorite type! I’ll grab my molecular socket wrench.
CALLI: Let’s take a look under the hood of venomous animals. Certain toxins in venom are actually quite common across very different species. Centipedes and snakes have more than a few common toxins between them. Showing off just how flexible venom can be.
NATE: I miss being flexible.
CALLI: It’s never too late to start hot yoga with me.
NATE: I should.
CALLI: Anyway, a recent study focused on some of the genes associated with venom. And, although these genes don’t create the toxins themselves, they set up the whole venom system in animals.
NATE: Building block genes.
CALLI: Exactly. And what the team discovered is pretty amazing - there’s a collection of genes commonly found in multiple body tissues across all amniotes! Isn’t that cool?!
NATE: Yeah of course. And I totally know why ... because I know what an amniote is, obviously. But, uh, maybe remind our audience?
CALLI: You should remember Nate, you’re an amniote yourself! Amniotes are animals that either fertilize their eggs internally, like humans, or that lay their eggs on land - including reptiles and birds.
NATE: So, we share these genes with them. That’s cool! And also, it means the genes are already in there!
CALLI: Yeah. So, these genes are involved in the folding of proteins.
NATE: “Folding proteins”? I’ve never folded a steak in half before but if science says to try it...
CALLI: No, no, not like that. Basically, proteins inside an animal's body are made up of long chains of amino acids. These chains will “fold” in on themselves to make proteins, which are then useful for creating larger structures in the body, like toxins.
NATE: So we share some of the same genes with venomous animals. And those genes play a big role in the creation of venom?
CALLI: You got it! These same sorts of genes are found in abundance in human salivary glands. And going even further - we also have the key protein that many venom systems are built from. And guess what protein that is...
NATE: Why do you look so excited?
CALLI: They’re called Kallikreins!
NATE: And the toxin is called Nate-ih-krines? No, probably not. Okay, besides having a cool name, what do these Kallikreins do?
CALLI: Well for starters they’re secreted in saliva. Which explains why so many animals have oral based venom systems. But they’re also very stable proteins, which allows them to continuously mutate based on the needs of the animal.
NATE: All this info sounds like humans are right on the cusp of having venomous spit.
CALLI: Not quite. In fact it’s pretty unlikely that we’ll ever actually develop our own venom system. We just don’t need to! Human strategies for self-defense and capturing prey are working great. In fact, so much energy is needed to make the proteins for the toxins, that we’ve actually seen some animals shift from being venomous to non-venomous creatures. There’s species of sea snakes that no longer need venom because they’ve switched their diet from fish to fish eggs.
NATE: All that cool venom and they gave it up! I guess it’s also kinda dangerous to have the venom around in general. I’ve always wondered that ... can animals poison themselves?
CALLI: They have a sort of toxin sponge protein they make to prevent that. So, more energy for making more proteins just to survive! But, that’s to prevent poisoning when the venom is confined to the glands that make them, and the nearby systems. If other parts of their body, like their brains, started to express these same genes - then they would die of auto-intoxication like you said. So a lot of research has gone into figuring out how gene expression is controlled in different parts of the body. Hopefully that research will enlighten us about diseases like cancer for example, which is often caused by tissues overgrowing and leaking products into the wrong places.
NATE: Well we may not get venom but we’ll at least make some medical progress.
CALLI: Not to mention all the current medical applications where venom has proven very helpful with issues like blood clotting and high blood pressure.
NATE: Perfect! With how creaky my knees are I’m assuming high blood pressure is next.
[SFX: Whoosh]
NATE: You know Calli I was driving around the other day and a thought struck me all of the sudden.
CALLI: Was it “whatever happened to the cast from Boy Meets World?” Because I wonder that quite a lot too.
NATE: No it wasn’t that. I was thinking - what happens to an electric car battery when it’s no longer usable?
CALLI: Does it go join all the other electric car batteries on a nice farm up north?
NATE: Turns out there’s quite a few companies dedicated to recycling electric car batteries. So, it’s more like a nice farm down south in Oklahoma City. Or out west in Nevada. Or wayyy out east in Europe.
CALLI: Makes sense - seems like everyone’s buying electric these days. They’re more efficient, better for the environment, I don’t really see the downside.
NATE: They’re great don’t get me wrong - and of course they take some potentially toxic materials to create initially, like most things, but when trying to repurpose them after their initial lives, they have some interesting issues!
CALLI: Like what?
NATE: For starters the batteries are notorious fire-starters when bundled together. I’m talking Nic Cage in Ghost Rider levels.
CALLI: Criminally underrated movie.
NATE: Sure... On top of that the primary materials used to make them, like lithium, are toxic when thrown away as waste. And don’t forget, some of them can be the length of the entire car and weigh over a thousand pounds!
CALLI: I feel like I might need a refresher on how these car batteries work. Didn’t we talk about something like this a few episodes ago?
NATE: We did! When we were discussing electric planes we talked about how a battery cell is made up of a cathode - the positive side, and an anode - the negative side. Plus a separator in between them.
CALLI: You’re mostly talking about lithium-ion batteries aren’t you? But we also talked about newer sodium-ion batteries many episodes ago.
NATE: Yes, great point! Sodium-ion battery development is on the rise and the future does look bright for its use. But for now, lithium-ion is the dominant model.
CALLI: Okay, so usually lithium battery, cathode, anode, separator. That’s a cell. And it’s one big thousand-pound cell?
NATE: No. Those singular cells are encased in a module by the dozens, or even hundreds. And it’s a set of modules that ... along with some other parts to keep voltage and cooling in check ... makes up a battery pack.
CALLI: Wow. I wonder how fast that would charge my phone...
NATE: It would probably make it explode.
CALLI: I’ve heard that’s a problem with handling EV car batteries.
NATE: They can be very dangerous to work with so it takes skilled technicians to examine them.
CALLI: Just like when I take Mr. Mittens to the vet.
NATE: Mr. Mittens needs special care, yes.
CALLI: So if these batteries are potentially that dangerous - what does the recycling process look like?
NATE: The material extraction process is difficult and expensive, but not all that complicated. Most batteries are shredded and then broken down with heat or chemicals.
CALLI: Seems straightforward enough.
NATE: The biggest hurdle in the process is the transportation of the old batteries. With studies showing that this process accounts for roughly forty percent of the total cost to recyclers.
CALLI: With all these negative factors playing into the recycling process - why even do it in the first place?
NATE: Because there could be a huge environmental and economic benefit once the right processes are in place. Re-using materials like cobalt and lithium would greatly lessen the toll that the mining of these materials takes on local areas. It could also be potentially much cheaper to consistently re-use these materials instead of sinking costs into mining operations.
CALLI: It’s just all around more efficient.
NATE: That’s the hope. And, the prices of materials are shifting, so re-purposing will become cheaper than making them anew. There’s still a long way to go before the recycling process is commonplace. Governments are working on appropriately regulating all this, but it’s a delicate line to balance. If the rules are too strict - to maximize “greenness” - then the widespread adoption of EV cars might slow down. But if the rules are too relaxed then the change may not happen fast enough.
CALLI: I really need to go trade my car in.
NATE: Be part of the change!
CALLI: I’m trying, I’m trying! If solid recycling processes are implemented how much material replacement are we looking at?
NATE: In theory we could see half of the cobalt, lithium, and nickel in EV cars come from recycling by 2040. And that’s even with an uptick in production. Like the one you’ll be part of soon when you trade your car in.
CALLI: I’ll make you a deal - you pay for half of a new Tesla for me, and I’ll go trade it in right now.
NATE: Or you could think of the money you’ll be saving on gas as a way of “recycling” it right back into your wallet.
CALLI: I wonder if Corey drives an electric car.
NATE: Corey?
CALLI: From Boy Meets World. He always seemed like an EV guy. Topanga definitely has one.
[SFX: Whoosh]
CALLI: Nate, do you like magic? Sleight of hand?
NATE: I actually do a bit myself!
CALLI: Hey, nice! I’m into it too. Sleight of hand especially. I love being fooled a little bit.
NATE: That's where all the fun is!
CALLI: new research is showing that people, unlike us ... people who don’t like magic ... well, they tend to have more socially aversive traits. In the psychology world that means they’re more likely to put themselves above others.
NATE: I can’t help but feel we’re a little biased bringing this topic up. But, you’re telling me people studied it, real scientists. Why?
CALLI: Well magic is interesting, right? It's more or less a worldwide phenomenon. It has ancient origins. It creates emotion through deception and the illusion of the impossible. It taps into uncertainty and curiosity, and it won’t explain these things at the end. It's pretty compelling since humans are always looking for answers to things, and yet they turn century after century to this not-knowing for entertainment.
NATE: You’ve just described reasons we like it, but what makes it good to study?
CALLI: Well, scientists felt if they unpacked all that, it may give them a new window into the human psyche. They looked at three different kinds of categories. First, curiosity, wonder and awe. Those are traits about whether a person is open to a new experience. Second, they looked at people’s tolerance for uncertainty. That’s all about how we deal with the unknown. Some folks see the world in black and white and might find the uncertainty of magic stressful.
NATE: And the last one?
CALLI: Interpersonal dominance. This trait is all about being in control when dealing with other people. Researchers wondered if these people would become more hostile towards magic in response to feeling like they were being deceived, manipulated, or made to look foolish, especially if the secret of the trick was never explained to them.
NATE: So how do you test for these things?
CALLI: they got together four groups for a total of fifteen-hundred and ninety-nine adult participants. Three groups were English speaking and one was Polish speaking. They then had each of these groups take different tests.
NATE: Like what?
CALLI: Well, importantly, they started with the Loathing of Legerdemain scale...
NATE: Legerdemain, that’s basically skill at sleight of hand.
CALLI: Exactly, yeah. Basically, people filled out a short survey that told the researchers directly how they felt about magic. After they collected that info, then they started getting into the juicy personal bits.
NATE: Are we talking about personality traits?
CALLI: Exactly, researchers assessed the big five personality traits: neuroticism, extraversion, openness, agreeableness, and conscientiousness. They also tested awe-proneness and curiosity.
NATE: How do you test that? Measure how far your jaw drops?
CALLI: You’re not far off. They measured chills and goosebumps. In another group they tested the need for structure and certainty as well as interpersonal dominance and perceived social status.
NATE: Another survey type thing?
CALLI: Yes. These questionnaires are designed to get a sense of these traits based on your preferences. Then, of course, they tested for the dark triad, Machiavellianism, narcissism and psychopathy.
NATE: So, who hates magic? What did we find out?
CALLI: Well the people who said they didn't like magic were less likely to be open to new experiences, less likely to experience awe, and were more often intolerant to uncertainty. These people also tended to have more disagreeable traits, like they were less amiable, scored higher in psychopathic qualities, and they were more dependent on controlling a given social interaction.
NATE: I knew I was right, if you don’t like magic, I’m just not sure we can hang out. I’d make that friendship disappear.
CALLI: Well, before we get ahead of ourselves, let’s admit, it's not all great for magic lovers. Interestingly the study found that sadists were more likely to enjoy magic.
NATE: Sadists? Like people who like causing other people pain?
CALLI: Yes! And researchers aren’t sure why that might be, but think it could be the attraction of deceiving others and creating confusion and surprise.
NATE: Well then I am going to seek out the magic lovers who like awe and wonder rather than confusion.
[SFX: Whoosh]
NATE: Let’s recap what we learned today to wrap up. New research shows that humans could evolve to have venom similar to animals like snakes. And even though this development is pretty unlikely, the study of the genes that would allow it could open doors to game-changing medical science.
CALLI: The EV transportation revolution is already upon us - but will the recycling of electric car batteries be a deterrent? Or will it be a gold mine? Regardless, we all know I really need to get a new car...
NATE: New research shows that people who don’t like magic are likely to have socially aversive traits. The study shows that they’re not only more likely to get uncomfortable with the uncertainty, but more likely to be disagreeable and aggressive.