Evolution in Action

gray hairs or whatever. Yeah, I know there's that one. Um no because it sounds kind of boring, you know, Um, But but no, But I mean there's there's like a YouTube video that the guy who like took a picture of himself like regular increments and then like put them all together in like a like a slide show, you know, and like like that's an example where you could you could actually watch yourself age a little. But but but not by just looking into the mirror, right right, It's

hard to detect, but we know what's going on. I remember going to an exhibit at the Moment in New York City a while back, and I got this book and it was a photography exhibit and the photographer took pictures every year of these four sisters, and so flipping through the book, um, you could see these women aging, you know, just as you've flipped. And it was so cool and it was so interesting. I really, I really

dug that. But yeah, aging is definitely hard to to notice unless you've had a couple of gray hairs poking out over Now, how do you know people were actually aging? How do you you know you're actually aging? Let's see the proof of it. I don't see aging right now? Right, you look like you're getting a little older doing this podcast. It wasn't that makes it sound like your hair sprouting out of those earphones. Yeah, well that just means I

need a haircut. But but the point I'm trying to make here is that another area that is very difficult to observe, and one of the criticisms often thrown at it is how do you know there's evolution? Like like we can see it. Yeah, we're let's see some evolution. I don't. I don't believe in evolution. Puts some on the table, dish out some evolution. Let's yeah, get put

in a bag. You can't do it, you know, because it's uh, because evolution occurs at increments over a very long period of time from generation to generation, right, And if you consider that Darwin's origin is species hasn't even been in print a mere hundred fifty one years, which is, you know, kind of a trap in the bucket. Yeah, that's nothing on on an evolutionary scale, right, So consider you know, how short of a time period we've been looking.

And that's not to discount the fossil record, because of course the fossil record does in fact provide us a good understanding of what's gone on in the past for organisms. Yeah, but one of the things with with looking back at fossils as you have like definite frozen moments in time, you know, in these different forms. But but it's it's much harder to see the movement, to see like the change from one form to the next, you know. Yeah, So we thought we'd cover a couple of evolution in

action studies today. Yeah. Yeah, these are examples of evolution in action and they're they're just great examples to really, you know, make evolution come alive to a certain extent, and they're occurring today. Yeah, So let's talk about the lizards. I feel like we always talk about lizards. Yeah, well lizards are great, pretty great, and uh yeah, we have a couple of studies. The first one is really cool.

This was a two thousand nine Pin State study and it dealt with these little fence lizards, you know, kind of like these little dudes you see running around, you know, everywhere. Yeah, and they're suffering from an invasion from the south fire ants guys. Yeah. And and they're they're in an area where they've just over the several decades have suddenly had to deal with fire ants and they've never had to deal with them before. Um, and so this is this

is a hallmark of evolution. You know, you have a species and suddenly the game has changed. You know, we have new food, we have new enemies, we have conflict. Yeah, because the the food thing is key, because it's not what you think the fire ants can eat the lizards. I was surprised by that. I mean you would think, obviously the lizards are going to come out on top here, but they're not, at least not the ones that are newly exposed to the fire ants. So let's get into

the details of the study. Yeah, so what what they decided to do was was to look at these like, not all the lizards are have encountered fire ants, yet some have been dealing with them for as long as like sixty eight years. Yeah. So they had four different groups, right, and they were looking at four different groups of lizards that had been exposed to fire ants in different increments.

One group had never encountered fire ants, and then like one had encountered them for like twenty three years, another encountered them for somewhere they were like forty something years, and then the fire extrain. There's the group that had been dealing with them for sixty eight years. They were sixty eight long years of fire ants veterans of the

Great Lizard fire ant War right there. So the researchers were trying to figure out, with time as a factor, how yeah, how they've adapted to this this new stimuli, you know, and which ones are going to be better

situated to deal with it. And apparently like the main defense against fire ants is too is to basically move your butt because because in the in the group that it like never encountered them before, like they will just sit there apparently, and the fire ants will crawl over them and the lizards defense is like, oh, I'm just gonna be real still still and shut my eyes. Yeah. And they took it. Yeah, and then they just get

them Yeah. Whereas the ones that are used to it, they'll know, hey, I need to move and or they flick them off. They flick them off or the leap away, you know, et cetera. Um, they have learned to deal with it. So they the researchers observed this behavior whether the lizards could you know, take it or get the heck out of there, But they also were interested in looking at the hind leg lengths of all the lizards.

Would they find Roberts Well, they found that lizards living near fire ants are they're developing behaviors to increase their survival and and evolving longer hind legs in response to the attacks from the fire ants. Okay, and so that was that was their exposure. It was the exposure the length of exposure that correlated. Yeah, And I should also mention that I believe one of the details in the study was that they didn't like kill a whole lot

of lizards in this like I think they were. They were like saving the lizards before they could be stung to death. That's nice. Yeah, but so as cool as the study is, it's not quite speciation now. It's more like these are the movements though that that can lead to it. But yeah, this is not These lizards aren't becoming a new breed of lizard, a new species of lizard. Um. But let's talk about where speciation may be occurring, in fact in White Sands, New Mexico. Yeah, this is another

lizard study. This is a two thousand ten University of Idaho study. And I actually talked to one of the people tied up in the research for this for this a story for Discovery News January UM. And this one deals with these brown lizards. Traditionally brown lizards. Uh that they but they live in an area called White Sands, New Mexico. And why do you think it's called White Sands,

New Mexico because there's white sand everywhere. Sounds kind they're a brown lizard though, Yeah, And what is a lizard and what is a lizard? One of the lizards traditional defense mechanisms camouflage, camouflage, so the the but they, of course, these lizards have changed over time over the course of say two to five thousand years, right, since they arrived there a couple of thousand years ago. Yeah, so so they were they were exploring how they've they've changed pigment

during this time. They've they've become these like white lizards and white sands. Yeah and uh. Anyway, they made the argument that that this is really one of the they're hit they've hit several of the road stops on the way to speciation. Um and uh. And you know, they've they've changed their color, that's a big one. But also they've started, uh having a preference for light colored lizards

when it comes to breeding. Really. Yeah, so it's like there, you know, it's sort of like imagine you know, it's like a line, you know, and one line is diverging slowly from the other. So you know, have you know, another ten thousand years, you know, you might have the white, the whitelizard, and the brown lizard of separate species entirely. So that's pretty cool, but not as cool as the equal I. Yeah, this this is a fantastic study and you guys may have heard it. It goes back to

what we were talking about with the generations. You know, it's like human generations. Um, it's hard, it's hard to really you know, we can't really watch it spread from generation generation. There haven't been that many generations since origin

of species, you know, et cetera. But if you can find a species that has really small generations, a short life cycle, short lived, it's like pushing the fast forward button right right, And a lot of times that the choice organisms might be drosophilia, your fruit flies, or or planel bacteria. And in this case in back in it was equally a single equally bacterium that in Michigan State University biologists used and he started twelve laboratory populations with it. Yeah,

this is Professor Richard Lynsky. Twenty years time. Lensky had generations on his hands. So if we were studying humans, this would be a phenomenal amount of time. Yeah, we'd be talking something in the neighborhood of like three million years of human evolution. So Lensky observed the bacteria as they grew larger and faster in response to the lab diets. Then what happened, Well, you hit around the thirty one

five generations, something special happens. Suddenly they're able to this one population of them are able to consume citrate, which is as nutrient that they've they've been surrounded by the whole time as as part of their medium. Yeah, their medium. Um, it's kind of like like imagine if you were like, it's like that they're gonna bring up the cats. That was one of my more way too complicated metaphor. Probert has to find a way to work in cats into

every podcast. It was just kind of like the buffet bar was there and they were eating most of it, and then one day suddenly they were able to eat the seafood portion of the buffet. Good. Good for them. But in this case it was the sit rate. So suddenly you had situate plus E. Coli. Yeah, so you went up with the population of mutated sitrate consuming bacteria and as you can imagine, that was a pretty handy ability to have, and so the population of that bacteria skyrocketed.

And now they call these sitrate plus equally. So here's also something very interesting about this experiment. You know, somebody's going to dismiss it as a one time thing, oh, as a fluke or whatever it as well, Lensky had a solution for this. So the whole time he and his team had been freezing samples every five hundred generations, so he was able to do a rewind and he was actually able to go back and replace some of the experiment and see if they could catch it again.

I mean, this is so cool. Yeah. Yeah, And and apparently they were like when they went back and they like replayed it, they were they found it like something was occurring in this in this one population at like the at the twenty thousand or so generation, like some small changes that were leading up to this ability to metabolize sits. Right. Yeah, and they're still working to figure out exactly what. Okay, so that's the question. Yeah, you know, what is the mechanism way? I mean, if they could

pinpoint it just a little bit more, that would be great. Yeah, I just get down to the we have the fine changes that are occurring. It reminds me a lot. I think there was like a Twilight Zone where like like the humans were observing the evolution of like a micro biological so it wasn't it was more than micro biological. It's like a tiny little civilization and like they watched

them grow, you know, developed like spaceships and stuff. And I think the Simpsons, so on a more sobering note, um, the ability of bacteria to evolve, or any organism to

evolve has pretty important implications, as you guys know. Um, you know, especially when you're talking about our fifty plus year war against harmful bacteria, when you're talking about things like extensively drug res stant tuberculosis UM, and then there are other So that's that's definitely yeah, in the in the same way that these citrate plus a cool I were suddenly able to deal with something in their environment that they hadn't you been around for too terribly long.

You know, we're having having some very harmful microbes out there that are you know, figuring how to out how to deal with the situations that we're throwing at them. I will tell you as a parent, it's sometimes terrifying to give your kid antibiotics. You know, I wonder, you know, is my kid going to evolve resistance to this? You know,

I it's it's just a little terrifying. And and then there's a there's a whole side with insects and pesticides as well, you know, where insects developing a resistance to certain pesticides over time. We you know, we throw out these solutions and we don't really realize that that nature is pretty good at evolving. It's pretty much all it does, you know, So given enough time, you know, it's it's remarkable what people think, you know, especially micro organisms will

be able to do. Like I was reading something of the day researching stuff about plastics, and there are some some predictions that like you know, you know, like tens and thousands of years, like you know, you'll you'll eventually have microbes that can can really break down plastics in a way that we can't. We don't see today because it's some new material. But give him enough time, they'll figure it out. Yeah. In the meantime, maybe just bring

your bags off to use plastic. Yeah, yeah, that's always always a good idea. So, speaking of plastic bags, we've got a plastic bag here full of reader mail. Let me grab when happen. They didn't really readers, some of them are readers, but listeners primarily listeners, I guess. Um. Yeah, so we got one here from Alicia. Oh. Alicia, she was the one who wrote into for to share her favorite bit of cosmos. Yeah. Yeah, she's one of She's a fan of some of our more cosmic entries in

the podcast series. Here and she says, Hey, Alison and Robert, this is a little something that I remembered after listening to your podcasts about the birth of stars and planets. Though this one this is more relevant to the death of stars. I just wanted to share my favorite factoid ever from cosmology. It was on casts the quote plasma soup unquote that resulted from the Big Bang consisted of

only very small particles like protons, electrons, et cetera. But there weren't any heavier elements that would have higher atomic numbers. But from what I can tell from my simplistic understanding of physics, when stars began to coalesce, the force of gravity pulling on the outside of the stars would cause immense amounts of pressure on the particles in the middle,

causing the nuclear fusion reactions and creating heavier and heavy elements. Thus, large stars will be able to create heavier, large, heavier elements closer to their centers. Then, if the star dies and becomes a supernova, it sends its particles scattering far and wide throughout the galaxy to later clampman become part of other stars, planets, and what have you. While I'm normally not a romantic. This literally means that we are all made of star dust. So yeah, that's that's awesome.

You know, we're all we're all star stuff. So that's that's kind of meat. It kind of you know, builds the soul like community of the universe. You know, we are the universe and the universe is us. Yeah, thanks Felicia and uh oh, and then we have another one here from uh oh thoughts from Alison ladder Milk. At first, that would really be cheap. You're writing in your own fan now sending anything listener will This one's from Natalie. Oh, Natalie, we even about right. Oh yeah, this's a long one.

There we go. Not as long as someone and if you just read some of the highlighted carts, okay, um, she says, first of all, I just want to say I'm a big fan of the show. I'm addicted to listening to the podcast just before bed or in the quiet moments of my free time. So we should really keep the yelling down. You might be trying to get to sleep. Um, that's I'll keep paying money. Your topics

are always very engaging and informative. Whenever I listen, I feel like I'm getting a brush up on concepts I missed while zoning out in high school science classes. Which is great, that's totty much as part of the whole mission Here, she says, I just finished listening to your podcast, A World Changing Science Experiments, Part two and was very interested in section on Pavlov and his experiments with dogs,

but had to send any meddle. Let you know I side. Now, let you know a side of path Law that is generally unknown to most. I just graduated in May two ten from CVE Denver with a bachelor's degree in psychology, and during my history of psychology class, we discussed path Law's work in great detail. I was surprised and disturbed to find that Pavlov used children orphans in fact, in the same manner as dogs and his experiments. I had

never heard. Yeah, and once he discovered that he could condition any unconditioned response, he wanted to see if humans humans would react in the same way. She goes on to say, much of my surprise, my professor showed a video of path Law working with both his children and his dogs, or both his dogs and these children. Despite this discovery, I'm still a fan of Pavlov's as his work was pivotal and understanding learning and behavior in humans

and other animals. Again, I love the show and that's great because that's I mean, that's always my experience with finding out more about science and science experiments is that it's always a little bit amazing and a little bit creepy,

depends on which side you look at it, you know. Yeah, So share your amazing stories or creepy stories with us, whether you're on Facebook, we're at a stuff from the science Lab, or Twitter we're on lab stuff, or send us an email and science stuff it has stuff first dot com. Yeah, let us know what you're up to and check out those sites and you'll be able to see what we're up to. All right, thanks for listening, Guys for more on this and thousands of other topics

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