Brought to you by the reinvented two thousand twelve camera. It's ready. Are you welcome to Stuff you should know? From how Stuff Works dot Com? Hey there, welcome to the podcast. I'm Chris Polette. I'm one of the editors here and with me, as always, is staff writer Josh Fark. You don't know, okay. I thought we would talk about what happens when animals evolve in isolation, and basically it starts with the theory of evolution and how we're all related exactly. Yeah, and like you said, you hit upon this theory. I think we should say that not everyone subscribes to evolution, but if you're a scientist, you most likely do. Um. There are a few ways to to go about uh evolving, and one of them is through evolution and isolation. Um. For that to happen, you have to go through a speci event. And what that is is just when one species becomes two or more species, for example, bears. You want to talk about bears, Sure we can talk about bears. Okay, Well, the black bear is the parent species of the polar bear, and it makes sense if you think about it. There bears, right, So surely all bears are related, But how did polar bears become white? Wire black bears still black? I think evolutionary biologists tend to believe that it was because of a parapatric speciation event. And parapatrick speciation occurs when UM, a species becomes so spread out geographically that members in different areas are are living in different environments undergoing different experiences. So the black bear up north had a fur coat that stood out like a sore thumb against the the white landscape, the snow covered landscape, so they evolved to be white. Uh, that's not enough. That doesn't cover speciation entirely. For speciation to be complete, you have to go through reproductive isolation. And this just means where the members of the species no longer can produce offspring. It can be because they developed different genitalia. It can be because they've developed different time to the year to make different locations to made in. Either way, if reproductive isolation occurs, aspeciation event has taken place, okay, um, So basically they just have to uh, they just have to be different enough where they're no longer able to reproduce with one another, and then gradually, you know, become a different species altogether. That's exactly right. And there's also some other really interesting aspects to evolution. One of THEE know you know a lot about that's the evolutionary bottleneck, right, that's true. This is when a group gets completely or I guess nearly completely cut off from the main group, so you know, they are reproducing only with one another. Um. It's it's like a bottleneck if you think, like a sodo bottle. UM. But you know that can cause some problems because if there's a genetic defect, it can be passed down from generation through generation. Uh. You mentioned in the article a group of Amish people in Pennsylvania who uh, who had smaller than had a trade for smaller than normal brains micro and cephali um. And uh, you know that can be fatal. So obviously, uh, you know, in this case, this very small group of people having that trade be passed down, it was was fatal to that group. Not a desired trade either, No, definitely not. But you know, Josh, one of the other examples that you used in the article that I thought was really cool was the iguanas that were displaced by Hurricane Maryland. UM. And that that's sort of an evolutionary bottleneck. And it's also an example of a different kind of uh speciation ala Patrick, which is, you know, they're cut off by a geographical boundary. In this case, they're on an island, separated by you know, the main group by water, and these these the small group of iguanas uh floated from Guadaloupe to Anguilla um. And I think that's I think that's really cool because you know, it's a completely scientific study. There are no or there were no iguanas on Anguilla before this happens. It's a completely natural experiment, right right. You know, they it wasn't forced. Um. They just happened to notice that the these iguanas are going to go there, and so they found out we're gonna find out if there will be a bottleneck. And also the island rule um, which is funny that this is an island, but uh yeah, the the island rule would give them a chance to see if these iguanas will grow larger or smaller as a result of being cut off from the main genetic body of iguanas UM. So it's gonna give give scientists a chance to see evolution up close and personal. As it were. Ironically, it was a gift from God to conduct a natural experiment on evolution. There you go. Well, you can read all about this and what happens when animals evolved in isolation on how stuff works dot com. For more on this and thousands of other topics, visit how stuff works dot com. Let us know what you think. Send an email to podcast that How stuff works dot com brought to you by the reinvented two thousand twelve Camri. It's ready, are you

Brought to you by the reinvented two thousand twelve camera. It's ready. Are you welcome to Stuff you should know? From how Stuff Works dot Com? Hey there, welcome to the podcast. I'm Chris Polette. I'm one of the editors here and with me, as always, is staff writer Josh Fark. You don't know, okay. I thought we would talk about what happens when animals evolve in isolation, and basically it starts with the theory of evolution and how we're all related exactly. Yeah, and like you said, you hit upon this theory. I think we should say that not everyone subscribes to evolution, but if you're a scientist, you most likely do. Um. There are a few ways to to go about uh evolving, and one of them is through evolution and isolation. Um. For that to happen, you have to go through a speci event. And what that is is just when one species becomes two or more species, for example, bears. You want to talk about bears, Sure we can talk about bears. Okay, Well, the black bear is the parent species of the polar bear, and it makes sense if you think about it. There bears, right, So surely all bears are related, But how did polar bears become white? Wire black bears still black? I think evolutionary biologists tend to believe that it was because of a parapatric speciation event. And parapatrick speciation occurs when UM, a species becomes so spread out geographically that members in different areas are are living in different environments undergoing different experiences. So the black bear up north had a fur coat that stood out like a sore thumb against the the white landscape, the snow covered landscape, so they evolved to be white. Uh, that's not enough. That doesn't cover speciation entirely. For speciation to be complete, you have to go through reproductive isolation. And this just means where the members of the species no longer can produce offspring. It can be because they developed different genitalia. It can be because they've developed different time to the year to make different locations to made in. Either way, if reproductive isolation occurs, aspeciation event has taken place, okay, um, So basically they just have to uh, they just have to be different enough where they're no longer able to reproduce with one another, and then gradually, you know, become a different species altogether. That's exactly right. And there's also some other really interesting aspects to evolution. One of THEE know you know a lot about that's the evolutionary bottleneck, right, that's true. This is when a group gets completely or I guess nearly completely cut off from the main group, so you know, they are reproducing only with one another. Um. It's it's like a bottleneck if you think, like a sodo bottle. UM. But you know that can cause some problems because if there's a genetic defect, it can be passed down from generation through generation. Uh. You mentioned in the article a group of Amish people in Pennsylvania who uh, who had smaller than had a trade for smaller than normal brains micro and cephali um. And uh, you know that can be fatal. So obviously, uh, you know, in this case, this very small group of people having that trade be passed down, it was was fatal to that group. Not a desired trade either, No, definitely not. But you know, Josh, one of the other examples that you used in the article that I thought was really cool was the iguanas that were displaced by Hurricane Maryland. UM. And that that's sort of an evolutionary bottleneck. And it's also an example of a different kind of uh speciation ala Patrick, which is, you know, they're cut off by a geographical boundary. In this case, they're on an island, separated by you know, the main group by water, and these these the small group of iguanas uh floated from Guadaloupe to Anguilla um. And I think that's I think that's really cool because you know, it's a completely scientific study. There are no or there were no iguanas on Anguilla before this happens. It's a completely natural experiment, right right. You know, they it wasn't forced. Um. They just happened to notice that the these iguanas are going to go there, and so they found out we're gonna find out if there will be a bottleneck. And also the island rule um, which is funny that this is an island, but uh yeah, the the island rule would give them a chance to see if these iguanas will grow larger or smaller as a result of being cut off from the main genetic body of iguanas UM. So it's gonna give give scientists a chance to see evolution up close and personal. As it were. Ironically, it was a gift from God to conduct a natural experiment on evolution. There you go. Well, you can read all about this and what happens when animals evolved in isolation on how stuff works dot com. For more on this and thousands of other topics, visit how stuff works dot com. Let us know what you think. Send an email to podcast that How stuff works dot com brought to you by the reinvented two thousand twelve Camri. It's ready, are you