Hey, welcome to Stuff to Blow Your Mind. My name is Robert.

Hey, welcome to Stuff to Blow Your Mind. My name is Robert.

Lamb and I am Joe McCormick, and we are out this week, so we're bringing you an episode from the vault. Today's episode originally aired on December eighth, twenty twenty two, and it is part one of our series on the reptiles of the Galapagos Islands.

Lamb and I am Joe McCormick, and we are out this week, so we're bringing you an episode from the vault. Today's episode originally aired on December eighth, twenty twenty two, and it is part one of our series on the reptiles of the Galapagos Islands.

All right, let's dive right in.

All right, let's dive right in.

Welcome to Stuff to Blow Your Mind, production of iHeartRadio.

Welcome to Stuff to Blow Your Mind, production of iHeartRadio.

Hey, welcome to Stuff to Blow Your Mind. My name is Robert Lamb.

Hey, welcome to Stuff to Blow Your Mind. My name is Robert Lamb.

And I'm Joe McCormick, and today we're beginning a series of episodes on the reptiles of the Galapagos Islands. And Rob, this is not a topic we just landed on randomly. This is related to your recent travels, right.

And I'm Joe McCormick, and today we're beginning a series of episodes on the reptiles of the Galapagos Islands. And Rob, this is not a topic we just landed on randomly. This is related to your recent travels, right.

Yeah. I had the great pleasure in the fortune to visit some of the islands of the Galapagos Archipella go back in October. It was a fantastic family trip that we'd been planning for a long time, that we meant to do before the pandemic and then obviously we had to reschedule. But yeah, this is this was one of the top trips I've ever had the privilege to make. And now certainly I was visiting as a tourist. But one of the things about the Galapagos Islands that I love is so much of the tourism there is about the natural beauty of the place. It's about the environments, it's about the animals. And so if you're going all the way to the Galapagos Islands, you probably want to see some reptiles, you probably want to see some birds, et cetera. And they really facilitate that. The local guides are all terrific, all the ones that I interacted with very knowledgeable of everything going on there. And yeah, it was a trip just unlike any other, especially when when observing these various creatures, because it was kind of like being a Disney princess, like being in a Disney like a Disney princess scene in a movie, except instead of the princess being surrounded by cute squirrels, bunnies and birds that are singing, you're just constantly surrounded by this wonderfully bizarre cast of reptiles and elaborate birds, sea lions, etc. And it's unlike too, I have to say, it's unlike the vibe that I've encountered in places like the Grand Canyon, where there'll be wild animals there that are protected and so accustomed to humans that the humans can get like unnaturally and alarmingly close to those animals. There's a proximity to the animals on the Galapagos Islands that feels less artificial but also equally magical, if that makes sense. Again, not to say that you should attempt to touch any of the animals there, or or or infringe upon their personal space in any way, but there's this, Yeah, there's this feeling of proximity to nature that makes you feel like you are David Attenborough in a David Attenborough documentary, you know, creeping up for a close look at this animal or another.

Yeah. I had the great pleasure in the fortune to visit some of the islands of the Galapagos Archipella go back in October. It was a fantastic family trip that we'd been planning for a long time, that we meant to do before the pandemic and then obviously we had to reschedule. But yeah, this is this was one of the top trips I've ever had the privilege to make. And now certainly I was visiting as a tourist. But one of the things about the Galapagos Islands that I love is so much of the tourism there is about the natural beauty of the place. It's about the environments, it's about the animals. And so if you're going all the way to the Galapagos Islands, you probably want to see some reptiles, you probably want to see some birds, et cetera. And they really facilitate that. The local guides are all terrific, all the ones that I interacted with very knowledgeable of everything going on there. And yeah, it was a trip just unlike any other, especially when when observing these various creatures, because it was kind of like being a Disney princess, like being in a Disney like a Disney princess scene in a movie, except instead of the princess being surrounded by cute squirrels, bunnies and birds that are singing, you're just constantly surrounded by this wonderfully bizarre cast of reptiles and elaborate birds, sea lions, etc. And it's unlike too, I have to say, it's unlike the vibe that I've encountered in places like the Grand Canyon, where there'll be wild animals there that are protected and so accustomed to humans that the humans can get like unnaturally and alarmingly close to those animals. There's a proximity to the animals on the Galapagos Islands that feels less artificial but also equally magical, if that makes sense. Again, not to say that you should attempt to touch any of the animals there, or or or infringe upon their personal space in any way, but there's this, Yeah, there's this feeling of proximity to nature that makes you feel like you are David Attenborough in a David Attenborough documentary, you know, creeping up for a close look at this animal or another.

And maybe you are the camera lens. And I wonder if the difference with the Grand Canyon thing would be the difference between animals that are unfortunately habituated to human presence in all the wrong ways, like expecting you to have food, the calorie rich food sources and stuff, so they'll come up to you looking for that, versus a place where animals don't seem to flee from humans because they come from many generations of animals without natural land predators.

And maybe you are the camera lens. And I wonder if the difference with the Grand Canyon thing would be the difference between animals that are unfortunately habituated to human presence in all the wrong ways, like expecting you to have food, the calorie rich food sources and stuff, so they'll come up to you looking for that, versus a place where animals don't seem to flee from humans because they come from many generations of animals without natural land predators.

Yeah, yeah, and I believe that is the case with the Glapicos. So let's let's introduce everybody to the Glapico silence. If you're not familiar with the Glapagos Archipelago, it is a chain of islands in the eastern Pacific Ocean, roughly nine hundred and sixty six kilometers or six hundred miles off the coast of Ecuador. It consists of thirteen major islands a few smaller islands, and these were all formed by repeated volcanic eruptions. The process here is similar to that which produced the Hawaiian Islands, which we've discussed in the show before. So they're not formed all at once, but in a chain due to underlying volcanic activity berthing mountains and islands out of the ocean floor. So, as with the Hawaiian Islands, the islands here in the Galapagos are geologically quite young and their individual ages vary. Now, Joe, I'm not sure what age ranges you've come across for them when we get into the geologic age of the Galapagos Islands, but I've seen it vary a bit. The Galapagos Conservatory says, quote, probably no more than five million years with the younger volcanically active westernmost islands perhaps as young as hundreds of thous sin of years old.

Yeah, yeah, and I believe that is the case with the Glapicos. So let's let's introduce everybody to the Glapico silence. If you're not familiar with the Glapagos Archipelago, it is a chain of islands in the eastern Pacific Ocean, roughly nine hundred and sixty six kilometers or six hundred miles off the coast of Ecuador. It consists of thirteen major islands a few smaller islands, and these were all formed by repeated volcanic eruptions. The process here is similar to that which produced the Hawaiian Islands, which we've discussed in the show before. So they're not formed all at once, but in a chain due to underlying volcanic activity berthing mountains and islands out of the ocean floor. So, as with the Hawaiian Islands, the islands here in the Galapagos are geologically quite young and their individual ages vary. Now, Joe, I'm not sure what age ranges you've come across for them when we get into the geologic age of the Galapagos Islands, but I've seen it vary a bit. The Galapagos Conservatory says, quote, probably no more than five million years with the younger volcanically active westernmost islands perhaps as young as hundreds of thous sin of years old.

But the idea that none of the islands there today are are more than five million years.

But the idea that none of the islands there today are are more than five million years.

Old according to some of the dates that I was looking at these sighted dates, but just sort of casting a wide net, I did see some other dates out there, so you know, I can only speak to the ones I'm citing here.

Old according to some of the dates that I was looking at these sighted dates, but just sort of casting a wide net, I did see some other dates out there, so you know, I can only speak to the ones I'm citing here.

Well, estimates vary a bit, but it also depends on what you're counting as the Galapagos Islands. For example, I was reading a passage in a book Galapagos a Natural History, second edition by John Creecher and Kevin Laughlin from Princeton University Press. That new edition is just out this year, in twenty twenty two, and there is a section in this book where the authors put forward the possibility that some species on the islands, including the famous giant tortoises, may have inhabited the Galapagos since before any of the Galapagos Islands existed. Now, how could that be possible? Well, here's what they argue. If you look around the area of the archipelago, especially east of the existing islands, you will see what are called sea mounts, which are submerged islands. They are areas where the ocean floor rises up to form a mountain, but that mountain does not break through the surface of the water. So it's not an island from our perspective, but it's sort of like an island just beneath the water. Now, what are these seamounts in the eastern part of the archipelago. Well, Creature and Laughlin write that they are quote eroded volcanic islands, and that they are possibly the original ancestral Galapagos. So they were once perhaps islands that did break above the surface, but have eroded over time. And the authors here cite a group of oceanographers and geologists led by a researcher named D. M. Christie, who put together some dates for these seamounts and said that the dates range from between five to not nine million years, which is older than any of the existing Galapagos islands today. So to read from this passage quote, as Christie's team pointed out, if the original Galapagos islands formed as much as nine million years ago, there has been more time for colonization and subsequent evolution than once believed. This is colonization by non human animals. There may well have been tortoises on the islands for longer than any of the present day islands have been in existence. Given regular, albeit accidental dispersal, new islands forming over the Hotspot will be colonized even as old islands erode and disappear beneath the sea from whence they came. So normally you're talking about an island group, you would imagine that, okay, well, the earliest it could have been colonized by animal species is whenever the islands we have today began. But in the case of the Galapagos, a lot of the evidence of the earliest colonization by animals could be under the waves. It could be lost because those islands aren't there anymore.

Well, estimates vary a bit, but it also depends on what you're counting as the Galapagos Islands. For example, I was reading a passage in a book Galapagos a Natural History, second edition by John Creecher and Kevin Laughlin from Princeton University Press. That new edition is just out this year, in twenty twenty two, and there is a section in this book where the authors put forward the possibility that some species on the islands, including the famous giant tortoises, may have inhabited the Galapagos since before any of the Galapagos Islands existed. Now, how could that be possible? Well, here's what they argue. If you look around the area of the archipelago, especially east of the existing islands, you will see what are called sea mounts, which are submerged islands. They are areas where the ocean floor rises up to form a mountain, but that mountain does not break through the surface of the water. So it's not an island from our perspective, but it's sort of like an island just beneath the water. Now, what are these seamounts in the eastern part of the archipelago. Well, Creature and Laughlin write that they are quote eroded volcanic islands, and that they are possibly the original ancestral Galapagos. So they were once perhaps islands that did break above the surface, but have eroded over time. And the authors here cite a group of oceanographers and geologists led by a researcher named D. M. Christie, who put together some dates for these seamounts and said that the dates range from between five to not nine million years, which is older than any of the existing Galapagos islands today. So to read from this passage quote, as Christie's team pointed out, if the original Galapagos islands formed as much as nine million years ago, there has been more time for colonization and subsequent evolution than once believed. This is colonization by non human animals. There may well have been tortoises on the islands for longer than any of the present day islands have been in existence. Given regular, albeit accidental dispersal, new islands forming over the Hotspot will be colonized even as old islands erode and disappear beneath the sea from whence they came. So normally you're talking about an island group, you would imagine that, okay, well, the earliest it could have been colonized by animal species is whenever the islands we have today began. But in the case of the Galapagos, a lot of the evidence of the earliest colonization by animals could be under the waves. It could be lost because those islands aren't there anymore.

The lost animal kingdoms of the Galapgos potentially. Now, when we're talking about the modern day Galapagos islands, some of the main ones, just to mention them real quick, you have Isabella, which is the largest. You have Santiago Fernandina, you have Santa Cruz, you have San Cristobol. I only really visited Santa Cruz and San Cristobal and a couple of smaller unoccupied by humans islands that were quite fascinating. And one of the things about these islands, and you've often counted this with volcanic island formations, is that they're defined by steep out elevation changes and the resulting islands that contain multiple micro climates due to this, So a visit to even a single Galapagos island is an encounter with multiple and varied ecosystems.

The lost animal kingdoms of the Galapgos potentially. Now, when we're talking about the modern day Galapagos islands, some of the main ones, just to mention them real quick, you have Isabella, which is the largest. You have Santiago Fernandina, you have Santa Cruz, you have San Cristobol. I only really visited Santa Cruz and San Cristobal and a couple of smaller unoccupied by humans islands that were quite fascinating. And one of the things about these islands, and you've often counted this with volcanic island formations, is that they're defined by steep out elevation changes and the resulting islands that contain multiple micro climates due to this, So a visit to even a single Galapagos island is an encounter with multiple and varied ecosystems.

Right, So you'll get different climates and different vegetation and so forth at different elevations on the island. So and that type of like what vegetation is flourishing therefore might vary with the seasons. So when the rainy season comes, you might get more blossoming of vegetation in the lower areas, but then other times animals might find the most fruitful foraging up in the highlands.

Right, So you'll get different climates and different vegetation and so forth at different elevations on the island. So and that type of like what vegetation is flourishing therefore might vary with the seasons. So when the rainy season comes, you might get more blossoming of vegetation in the lower areas, but then other times animals might find the most fruitful foraging up in the highlands.

Yeah. Yeah, So it's any one of these islands, you'll have you have sort of desert environments, you'll have highland lush environments, you'll have coastal environments, and these are these are This is one of the reasons that these islands are often singled out historically, but even in modern research is kind of a laboratory of evolution. Now, I'm going to keep referring back to Hawaii a little bit for a while because I think it's a nice sort of touchdown to compare, especially since we've talked about those islands on the show before as well. So when it comes to Hawaii, as we've discussed before, you have such geographic isolation that with those islands, so that there are actually no native land reptiles or amphibians there. So anything in the categorization of reptil or amphibian that you find there were introduced by subsequent human arrivals by boat or ultimately air. That's the Hawaiian Islands. We don't have the same situation with the glabgos islence for a few different reasons. So as far as humans go, first, human contact with Galapagos comes a bit later. We're talking about fifteen thirty five versus Hawaii's between one twenty four CE and eleven twenty CE. Also, Hawaii is a greater distance from the nearest continental land mass. And I should note that I think I've pointed this Alma show before, but there is some dispute on whether the Inca ever reached the island, but we can be certain that Europeans reached the island in fifteen thirty five.

Yeah. Yeah, So it's any one of these islands, you'll have you have sort of desert environments, you'll have highland lush environments, you'll have coastal environments, and these are these are This is one of the reasons that these islands are often singled out historically, but even in modern research is kind of a laboratory of evolution. Now, I'm going to keep referring back to Hawaii a little bit for a while because I think it's a nice sort of touchdown to compare, especially since we've talked about those islands on the show before as well. So when it comes to Hawaii, as we've discussed before, you have such geographic isolation that with those islands, so that there are actually no native land reptiles or amphibians there. So anything in the categorization of reptil or amphibian that you find there were introduced by subsequent human arrivals by boat or ultimately air. That's the Hawaiian Islands. We don't have the same situation with the glabgos islence for a few different reasons. So as far as humans go, first, human contact with Galapagos comes a bit later. We're talking about fifteen thirty five versus Hawaii's between one twenty four CE and eleven twenty CE. Also, Hawaii is a greater distance from the nearest continental land mass. And I should note that I think I've pointed this Alma show before, but there is some dispute on whether the Inca ever reached the island, but we can be certain that Europeans reached the island in fifteen thirty five.

Yeah, exactly three hundred years before Darwin did.

Yeah, exactly three hundred years before Darwin did.

By the way, Yeah yeah.

By the way, Yeah yeah.

So the story of the first confirmed human landing on the Galapagos is very interesting, so I wanted to tell it here. There was this Spanish clergyman named Tomas de Berlonga who was a bishop eventually served as the bishop of the Colony of Panama, and I've read it alleged in several sources that Berloga was responsible for introducing bananas or plantains to the New World, which is weird because despite how much we associate bananas with the Caribbean and South America, they are originally native to Southeast Asia. So it is alleged that this guy's responsible for bringing bananas over, but I'm not sure what the original source of this claim is. Anyway, in fifteen thirty five, Berloga was traveling by ship from Panama to Peru to help sort out some kind of horrible sounding squabble between the conquistador Francisco Pizarro and another conquistador over land and spoils after their conquest of the Inca Empire, so Burlonga's on the way down to try to help sort this out. But as his ship is traveling south along the coast during the first half of the journey, it is suddenly struck by a dead calm that prevents the ship from sailing further, and then it gets dragged far off course out to sea by strong ocean currents, and just when supplies, including fresh water, are about to run out, the crew sits land. Their prayers have been answered, but like so many early visitors, these Spaniards are almost instantly dejected by what they find. The first island where they land is found to have not a single drop of fresh water, and there's also no pasture where their horses can graze, just a bunch of giant tortoises and weird iguanas. But there were other islands nearby, so the crew tried to sail to another one to continue the search for water. Unfortunately, on the way they were once again becalmed and could not sail for several days, while just languishing there on the ship, nearly dying of thirst. Finally the wind picked up again and they were able to reach a second island, where once again they found no fresh water. They tried to dig a well, but when they struck groundwater, they found it to be as bitter as the sea. And here I want to read from the retelling of this story by the famous naturalist William Biebe in his book Galapagos World's End, published in nineteen twenty four, BB writes, in their extremity, they had recourse to a plant which has saved many a thirsty man and animal, And by chewing the fruit and juicy stalks of the cactus they kept themselves alive.

So the story of the first confirmed human landing on the Galapagos is very interesting, so I wanted to tell it here. There was this Spanish clergyman named Tomas de Berlonga who was a bishop eventually served as the bishop of the Colony of Panama, and I've read it alleged in several sources that Berloga was responsible for introducing bananas or plantains to the New World, which is weird because despite how much we associate bananas with the Caribbean and South America, they are originally native to Southeast Asia. So it is alleged that this guy's responsible for bringing bananas over, but I'm not sure what the original source of this claim is. Anyway, in fifteen thirty five, Berloga was traveling by ship from Panama to Peru to help sort out some kind of horrible sounding squabble between the conquistador Francisco Pizarro and another conquistador over land and spoils after their conquest of the Inca Empire, so Burlonga's on the way down to try to help sort this out. But as his ship is traveling south along the coast during the first half of the journey, it is suddenly struck by a dead calm that prevents the ship from sailing further, and then it gets dragged far off course out to sea by strong ocean currents, and just when supplies, including fresh water, are about to run out, the crew sits land. Their prayers have been answered, but like so many early visitors, these Spaniards are almost instantly dejected by what they find. The first island where they land is found to have not a single drop of fresh water, and there's also no pasture where their horses can graze, just a bunch of giant tortoises and weird iguanas. But there were other islands nearby, so the crew tried to sail to another one to continue the search for water. Unfortunately, on the way they were once again becalmed and could not sail for several days, while just languishing there on the ship, nearly dying of thirst. Finally the wind picked up again and they were able to reach a second island, where once again they found no fresh water. They tried to dig a well, but when they struck groundwater, they found it to be as bitter as the sea. And here I want to read from the retelling of this story by the famous naturalist William Biebe in his book Galapagos World's End, published in nineteen twenty four, BB writes, in their extremity, they had recourse to a plant which has saved many a thirsty man and animal, And by chewing the fruit and juicy stalks of the cactus they kept themselves alive.

They took a page from the tortoise playbook. There.

They took a page from the tortoise playbook. There.

Yeah, not all withstood these privations. One man and two horses died of thirst, and so the first grave on the Galapagos was dug. Sunday came and the bishop celebrated high Mass on those desolate shores, where as he said, quote, it looked as though God had caused it to rain stone ones, brutal doom metal bishop. And then BB goes on sea. Lions slipped through the creaming surf and looked curiously at the little group of strange beings, and long winged seabirds poised and swooped above the cross and the Spanish flag planted side by side among the cactus and thorny scrub. So I think BB's taken a little liberty with the storytelling there, but all plausible, you know, given the local flora and fauna.

Yeah, not all withstood these privations. One man and two horses died of thirst, and so the first grave on the Galapagos was dug. Sunday came and the bishop celebrated high Mass on those desolate shores, where as he said, quote, it looked as though God had caused it to rain stone ones, brutal doom metal bishop. And then BB goes on sea. Lions slipped through the creaming surf and looked curiously at the little group of strange beings, and long winged seabirds poised and swooped above the cross and the Spanish flag planted side by side among the cactus and thorny scrub. So I think BB's taken a little liberty with the storytelling there, but all plausible, you know, given the local flora and fauna.

Yeah, desolate beaches, weird sea lions hanging about. Well, I guess the sea lions are generally described you as weird. They would have certainly been exposed to sea lions already, but in my books, sea lions are inherently strange but also very amusing to watch.

Yeah, desolate beaches, weird sea lions hanging about. Well, I guess the sea lions are generally described you as weird. They would have certainly been exposed to sea lions already, but in my books, sea lions are inherently strange but also very amusing to watch.

They're just playfully rolling about while these people have church, dying of thirst. So finally, after the worship service, the Spaniards did find some small amount of fresh water. I've seen what they found, alternately described as spring water and as little pools collected in cup shaped depressions in the rocks. And using this water, either the spring water or the rock pools, they filled up their containers and they departed again for the coast of Peru. Now, Burlanga made a number of observations while on the island, writing, according to an eighteen eighty four translation of his letters, that the animals of the Galapagos were quote so silly that they did not know how to flee, and that as a result, wild animals were easily caught in the hand.

They're just playfully rolling about while these people have church, dying of thirst. So finally, after the worship service, the Spaniards did find some small amount of fresh water. I've seen what they found, alternately described as spring water and as little pools collected in cup shaped depressions in the rocks. And using this water, either the spring water or the rock pools, they filled up their containers and they departed again for the coast of Peru. Now, Burlanga made a number of observations while on the island, writing, according to an eighteen eighty four translation of his letters, that the animals of the Galapagos were quote so silly that they did not know how to flee, and that as a result, wild animals were easily caught in the hand.

Well, that does match up, I think with the reality of visiting the Glabgos Islands even today. Not that you should be chasing any of the animals and certainly not catching them in the hand. But yeah, there is this, like I said, there's this sense that they don't necessarily understand what we are and they're not threatened by us unless we get too close, and then a lot of these animals will let you know. So, yeah, don't get too close to the sea lions wherever you find your sea lions. Don't get too close to the tortoises of the Iguanas.

Well, that does match up, I think with the reality of visiting the Glabgos Islands even today. Not that you should be chasing any of the animals and certainly not catching them in the hand. But yeah, there is this, like I said, there's this sense that they don't necessarily understand what we are and they're not threatened by us unless we get too close, and then a lot of these animals will let you know. So, yeah, don't get too close to the sea lions wherever you find your sea lions. Don't get too close to the tortoises of the Iguanas.

Now, Rob, you mentioned that the tourism at the Galapagos today is almost entirely centered around the island's natural beauty and biological and ecological significance. You know, this is a place where you go to see the natural landscape and the flora and fauna. You're not going there to see to go to six Flags Galapagos.

Now, Rob, you mentioned that the tourism at the Galapagos today is almost entirely centered around the island's natural beauty and biological and ecological significance. You know, this is a place where you go to see the natural landscape and the flora and fauna. You're not going there to see to go to six Flags Galapagos.

Right right, Yeah, Yeah, I mainly mean, yeah, you're not going to find that. You're not going to find I didn't really see much in the way of like a party boat kind of culture that you find in a lot of locations. It's you know that there is there is culture there. There's some great restaurants, there's there's great local culture. And the people who live there were on the whole very friendly and and I loved interacting with them quite a bit. But yeah, it's when people go to the Galapagos. I mean, the main selling point, the big deal for everyone seems to be the natural world that is avail to you there.

Right right, Yeah, Yeah, I mainly mean, yeah, you're not going to find that. You're not going to find I didn't really see much in the way of like a party boat kind of culture that you find in a lot of locations. It's you know that there is there is culture there. There's some great restaurants, there's there's great local culture. And the people who live there were on the whole very friendly and and I loved interacting with them quite a bit. But yeah, it's when people go to the Galapagos. I mean, the main selling point, the big deal for everyone seems to be the natural world that is avail to you there.

And despite this modern appreciation for the natural beauty and wondrous ecological significance of the Galapagos, a recurring theme among early visitors is a reaction exactly the opposite. So in the novel Galapagos, Kurt Vonnegut wrote that the early Spanish explorers quote did not claim the islands for Spain any more than they would have claimed Hell for Spain.

And despite this modern appreciation for the natural beauty and wondrous ecological significance of the Galapagos, a recurring theme among early visitors is a reaction exactly the opposite. So in the novel Galapagos, Kurt Vonnegut wrote that the early Spanish explorers quote did not claim the islands for Spain any more than they would have claimed Hell for Spain.

I haven't read this novel, but I did see it in bookstore. There was a nice bookstore on one of the islands in the Galapagos, and they had it there. They were probably had several Darwin related books, and then they had Vonneguts Galapagos, and I was tempted to pick it up, but then I was like, I don't know if I'm in the mid post apocalyptic literature at the moment.

I haven't read this novel, but I did see it in bookstore. There was a nice bookstore on one of the islands in the Galapagos, and they had it there. They were probably had several Darwin related books, and then they had Vonneguts Galapagos, and I was tempted to pick it up, but then I was like, I don't know if I'm in the mid post apocalyptic literature at the moment.

I've actually never read that one either, but so, yeah, it just seemed like the Spanish were not very interested for a while. There were apparently no notable mineral riches to mine, at least that they were aware of, no people living there to conquer or enslave. There was very little fresh water, so the Spanish just did not seem very interested in these islands. And during the seventeenth century it seems like the Galapagos largely served as a base for people who didn't want to be found, for pirates and privateers. Privateers would attack Spanish ships to steal the gold that the Spanish had stolen from the Incas, or just pirates who attacked and raided coastal settlements on the mainland.

I've actually never read that one either, but so, yeah, it just seemed like the Spanish were not very interested for a while. There were apparently no notable mineral riches to mine, at least that they were aware of, no people living there to conquer or enslave. There was very little fresh water, so the Spanish just did not seem very interested in these islands. And during the seventeenth century it seems like the Galapagos largely served as a base for people who didn't want to be found, for pirates and privateers. Privateers would attack Spanish ships to steal the gold that the Spanish had stolen from the Incas, or just pirates who attacked and raided coastal settlements on the mainland.

Yeah. Yeah, when it comes to the human history of the Glavigos, it's easy to sort of think, oh, well, Darwin and then you sort of fast forward to today. But yeah, there's a lot of bloody history there. It was an extreme location that, like you said, didn't have a lot seemingly to offer except as a place of refuge for people engaged in various bloody activities. Sometimes it seemed like a place for utopian ideals, and of course those sorts of ventures don't always turn out well either. So yeah, there's there's a very interesting human history there that is not all just bird watching by any means.

Yeah. Yeah, when it comes to the human history of the Glavigos, it's easy to sort of think, oh, well, Darwin and then you sort of fast forward to today. But yeah, there's a lot of bloody history there. It was an extreme location that, like you said, didn't have a lot seemingly to offer except as a place of refuge for people engaged in various bloody activities. Sometimes it seemed like a place for utopian ideals, and of course those sorts of ventures don't always turn out well either. So yeah, there's there's a very interesting human history there that is not all just bird watching by any means.

Mm hmm. Though, continuing the theme of like the the lack of appeal of the islands too many people who first arrived there, Charles Darwin himself wrote of his first impression of San Cristobal Island that quote, nothing could be less inviting.

Mm hmm. Though, continuing the theme of like the the lack of appeal of the islands too many people who first arrived there, Charles Darwin himself wrote of his first impression of San Cristobal Island that quote, nothing could be less inviting.

That's that's that's funny because they are on San Cristobal Island. You know, there's like a statue of Charles Darwin and the ship with his hand out and I had my I got my picture made with this, of course. But there, yeah, there are statues of Darwin all over the islands.

That's that's that's funny because they are on San Cristobal Island. You know, there's like a statue of Charles Darwin and the ship with his hand out and I had my I got my picture made with this, of course. But there, yeah, there are statues of Darwin all over the islands.

Nice. Now, well, yeah, I mean, you know, Darwin warmed up, you know, he there's a lot to learn there. But but yeah, apparently first setting eyes on it, he was like, h not cool.

Nice. Now, well, yeah, I mean, you know, Darwin warmed up, you know, he there's a lot to learn there. But but yeah, apparently first setting eyes on it, he was like, h not cool.

Yeah, that's not the quote. That's like on a plaque beside this statue.

Yeah, that's not the quote. That's like on a plaque beside this statue.

Now, regarding this story about Burlonga's accidental landfall in the Galapagos being the first confirmed human visit, It is important to stress that this is the first visit by humans we're sure about, but there are all kinds of interesting arguments about whether or not others had been there before, and their theories of contact regarding the Incas, Pacific peoples and so forth. But I think all of these are speculative and the evidence is questionable. There was certainly no permanent human settlement in pre Columbian times, and the earliest arrivals by humans appear to be by accident.

Now, regarding this story about Burlonga's accidental landfall in the Galapagos being the first confirmed human visit, It is important to stress that this is the first visit by humans we're sure about, but there are all kinds of interesting arguments about whether or not others had been there before, and their theories of contact regarding the Incas, Pacific peoples and so forth. But I think all of these are speculative and the evidence is questionable. There was certainly no permanent human settlement in pre Columbian times, and the earliest arrivals by humans appear to be by accident.

Yeah, you get into that situation though, where if earlier peoples had come there, they probably wouldn't have stuck around, and what would they have left behind, what evidence would there be, So yeah, we're left to speculation. Now, coming back around to the reptiles, which is going to be the main thing we're talking about in these episodes. Again, the Hawaiian Islands no native reptiles, but we have these fascinating examples of reptiles on the Galapagos. So while reptiles never had a chance to reach the Hawaiian Islands on their own, the Galapagos Islands are in just the right position. It seems to have been gifted some wandering, lost at sea reptiles, and yet at the same time isolated enough that they were able to evolve there unmolested for a very long time. So it's kind of fascinating to think about that. Like if they had been in any other location, you know, there might have been a situation where, yes, humans would have found this place and colonized it much earlier. It might be in a position where these reptiles would not have reached it of their own power or by the power of wind and water, which seems to be the case. I think the main examples of terrestrial reptiles reaching the Galapagos Islands, they tend to involve rafting. They tend to involve animals being just swept out to see via rivers in South America. And then a number of those animals are going to perish, but some of them are going to find themselves cast upon a deserted island, and from there they begin to find ways to survive and these new forms evolve.

Yeah, you get into that situation though, where if earlier peoples had come there, they probably wouldn't have stuck around, and what would they have left behind, what evidence would there be, So yeah, we're left to speculation. Now, coming back around to the reptiles, which is going to be the main thing we're talking about in these episodes. Again, the Hawaiian Islands no native reptiles, but we have these fascinating examples of reptiles on the Galapagos. So while reptiles never had a chance to reach the Hawaiian Islands on their own, the Galapagos Islands are in just the right position. It seems to have been gifted some wandering, lost at sea reptiles, and yet at the same time isolated enough that they were able to evolve there unmolested for a very long time. So it's kind of fascinating to think about that. Like if they had been in any other location, you know, there might have been a situation where, yes, humans would have found this place and colonized it much earlier. It might be in a position where these reptiles would not have reached it of their own power or by the power of wind and water, which seems to be the case. I think the main examples of terrestrial reptiles reaching the Galapagos Islands, they tend to involve rafting. They tend to involve animals being just swept out to see via rivers in South America. And then a number of those animals are going to perish, but some of them are going to find themselves cast upon a deserted island, and from there they begin to find ways to survive and these new forms evolve.

Well, this sounds like a perfect transition to the marine iguana.

Well, this sounds like a perfect transition to the marine iguana.

Robert You ready, Yeah, let's talk about the marine iguana. Probably not the most famous denizen of the islands, but at least number two.

Robert You ready, Yeah, let's talk about the marine iguana. Probably not the most famous denizen of the islands, but at least number two.

Yeah, yeah, and certainly maybe the most salient in my brain because specifically, to come back to Darwin, Charles Darwin's discussion of the marine iguana, or the scientific name ambly Rincus Christadis in the Voyage of the Beagle has long stuck in my head. So of course, the Voyage of the Beagle is the common name used to refer to the published writings of Charles Darwin after his sales on the HMS b Gole with Captain Fitzroy, and this chapter on the Galapagos in the Voyage of the Beagle is very famous, but the subsection on the marine iguana has long stuck in my head, notably for the weird disrespect with which Darwin treats these animals. So I want to read a few selections as we go about here from this passage in the Beagle, with some abridgments. But to start off, this is what Darwin says talking about the marine iguana. It is extremely common on all the islands throughout the group, and lives exclusively on the rocky sea beaches, being never found at least I never saw one even ten yards in shore. It is a hideous looking creature of a dirty black color, stupid and sluggish in its movements. And in his journal he refers to them initially as quote large disgusting, clumsy lizards.

Yeah, yeah, and certainly maybe the most salient in my brain because specifically, to come back to Darwin, Charles Darwin's discussion of the marine iguana, or the scientific name ambly Rincus Christadis in the Voyage of the Beagle has long stuck in my head. So of course, the Voyage of the Beagle is the common name used to refer to the published writings of Charles Darwin after his sales on the HMS b Gole with Captain Fitzroy, and this chapter on the Galapagos in the Voyage of the Beagle is very famous, but the subsection on the marine iguana has long stuck in my head, notably for the weird disrespect with which Darwin treats these animals. So I want to read a few selections as we go about here from this passage in the Beagle, with some abridgments. But to start off, this is what Darwin says talking about the marine iguana. It is extremely common on all the islands throughout the group, and lives exclusively on the rocky sea beaches, being never found at least I never saw one even ten yards in shore. It is a hideous looking creature of a dirty black color, stupid and sluggish in its movements. And in his journal he refers to them initially as quote large disgusting, clumsy lizards.

I mean they do lay around in clumps, which I could imagine some seeing this as being kind of gross looking. But in the same and this on the same note, the way they kind of lounge around sometimes they they seem oddly human in the way like one all sometimes have an arm slung over the shoulder of another, like it's like it's two, like as an old married couple staring out at the sunset or something. Puppy pile, yeah, yeah, kind of a puppy pile. And and there is kind of an awkwardness to them sometimes when they move around on land. But I don't know, that's kind of charming more than anything.

I mean they do lay around in clumps, which I could imagine some seeing this as being kind of gross looking. But in the same and this on the same note, the way they kind of lounge around sometimes they they seem oddly human in the way like one all sometimes have an arm slung over the shoulder of another, like it's like it's two, like as an old married couple staring out at the sunset or something. Puppy pile, yeah, yeah, kind of a puppy pile. And and there is kind of an awkwardness to them sometimes when they move around on land. But I don't know, that's kind of charming more than anything.

So early chroniclers often use the same kind of terms. They call this animal ugly, hideous. Some of them make bizarre value statements, such as comparing them to devils or imps of darkness. Uh Darwin himself in the Beagle quote say description by a previous author, a Captain Colnett, who visited the Galapagos, who says in the part of his work that Darwin quotes, quote, they go to sea in herds of fishing and sun themselves on the rocks, and maybe called alligators in miniature and elsewhere. Coln It marveled at their ugliness, writing quote, so disgusting is their appearance that no one on board could be prevailed upon to take them as food. Not even sailors would eat them. And I'm going to say I take personal offense to all this. I think marine iguanas are beautiful. I want to hug and kiss them. I know I shouldn't. I would never do that, but I want to.

So early chroniclers often use the same kind of terms. They call this animal ugly, hideous. Some of them make bizarre value statements, such as comparing them to devils or imps of darkness. Uh Darwin himself in the Beagle quote say description by a previous author, a Captain Colnett, who visited the Galapagos, who says in the part of his work that Darwin quotes, quote, they go to sea in herds of fishing and sun themselves on the rocks, and maybe called alligators in miniature and elsewhere. Coln It marveled at their ugliness, writing quote, so disgusting is their appearance that no one on board could be prevailed upon to take them as food. Not even sailors would eat them. And I'm going to say I take personal offense to all this. I think marine iguanas are beautiful. I want to hug and kiss them. I know I shouldn't. I would never do that, but I want to.

Yeah, they do look kind of like yemps, but I think in a good way. We often thought that they looked kind of like tiny godzillas. Something about the shape of their their heads and their snouts, and of course the little, you know, protrusions on the top of their head gives them kind of a kaiju appearance. And there's so many things about them. There's a lot of times you know they're lounging around, they're not doing anything, but then when they are moving about, even on the land, they can be quite amusing. Like, for instance, if one is making a bee line for something, especially if one is coming out of the water or it's time to go to the water. Sometimes something will seem to get in the way of their their journey, like maybe a sea lion or a human wanders into their path, and they'll just kind of stop and they'll they won't skitter out of the way or anything, but there just kind of wait until whatever it did is has moved on, and then they'll keep going. So there's this kind of like laid back care free of energy to these creatures.

Yeah, they do look kind of like yemps, but I think in a good way. We often thought that they looked kind of like tiny godzillas. Something about the shape of their their heads and their snouts, and of course the little, you know, protrusions on the top of their head gives them kind of a kaiju appearance. And there's so many things about them. There's a lot of times you know they're lounging around, they're not doing anything, but then when they are moving about, even on the land, they can be quite amusing. Like, for instance, if one is making a bee line for something, especially if one is coming out of the water or it's time to go to the water. Sometimes something will seem to get in the way of their their journey, like maybe a sea lion or a human wanders into their path, and they'll just kind of stop and they'll they won't skitter out of the way or anything, but there just kind of wait until whatever it did is has moved on, and then they'll keep going. So there's this kind of like laid back care free of energy to these creatures.

They're kind of wasted away again in Margueritaville.

They're kind of wasted away again in Margueritaville.

Yeah.

Yeah.

Yeah, by the way, you mentioned their stubby little snouts. That's actually what the genus name means, ambly Rincus means blunt snout.

Yeah, by the way, you mentioned their stubby little snouts. That's actually what the genus name means, ambly Rincus means blunt snout.

Ah. Well, we'll come back to the blunt snout of that.

Ah. Well, we'll come back to the blunt snout of that.

However, to come back to Darwin's writings on the marine Iguaana his unseemly anti iguana prejudice aside, he does make some correct observations about them. For example, Captain Colnet remembers said that they go a fishing in sea herds. You know they're going to go out and catch fish. Darwin says, I don't know about that. He challenges the idea that they eat fish, and in fact we now know they do not. Instead, Darwin observes that these animals seem to subsist on a kind of seaweed or algae which cannot be found on land, and he reasons that this explains why they evolved to go to sea in the first place.

However, to come back to Darwin's writings on the marine Iguaana his unseemly anti iguana prejudice aside, he does make some correct observations about them. For example, Captain Colnet remembers said that they go a fishing in sea herds. You know they're going to go out and catch fish. Darwin says, I don't know about that. He challenges the idea that they eat fish, and in fact we now know they do not. Instead, Darwin observes that these animals seem to subsist on a kind of seaweed or algae which cannot be found on land, and he reasons that this explains why they evolved to go to sea in the first place.

Yeah, and this is spot on, of course, and we'll get into it more in a bit, but yeah, and it's also very observable if you're watching the creatures, because sometimes they're going to be eating algae that's under the water and perhaps out of you. But other times it's algae, especially as the tides change, it's like partially in partially out of the water, so you can see them they're munching, grazing on the algae on the rock.

Yeah, and this is spot on, of course, and we'll get into it more in a bit, but yeah, and it's also very observable if you're watching the creatures, because sometimes they're going to be eating algae that's under the water and perhaps out of you. But other times it's algae, especially as the tides change, it's like partially in partially out of the water, so you can see them they're munching, grazing on the algae on the rock.

Though as a side note, Darwin says one dissected iguana stomach did have a piece of crab in it, though he thinks this might have been eaten by accident, and he compares this to cases where a vegetarian tortoise has a caterpillar in its stomach, because the caterpillar was just on the leafy vegetation the tortoise was eating. In fact, we've done whole segments about this on the show before, about herbivores eating animals accidentally or even sometimes on purpose.

Though as a side note, Darwin says one dissected iguana stomach did have a piece of crab in it, though he thinks this might have been eaten by accident, and he compares this to cases where a vegetarian tortoise has a caterpillar in its stomach, because the caterpillar was just on the leafy vegetation the tortoise was eating. In fact, we've done whole segments about this on the show before, about herbivores eating animals accidentally or even sometimes on purpose.

Yeah.

Yeah.

But after introducing them, Darwin goes on to describe the animals in detail, describing their movements with a strange mix of admiration and disgust. So here's what he says. Quote. When in the water, this lizard swims with perfect ease and quickness by a serpentine movement of its body and flattened tail, the legs being motionless and closely collapsed on its sides. A seman on board sank one with a heavy weight attached to it, thinking thus to kill it directly, But when an hour afterwards he drew up the line, it was quite active. Their limbs and strong claws are admirably adapted for crawling over the rugged and fissured masses of lava which everywhere form the coast. In such situations, a group of six or seven of these hideous reptiles may oftentimes be seen on the black rocks a few feet above the surf, basking in the sun with outstretched legs. And then he goes on to note a strange, perplexing, almost contradictory observation about their behavior. So, while the iguanas go to sea in order to forage, that's how they make a living, They swim out in the water, get the algae and eat it. He found that he could not scare them into the water. If he approached one, it would back away from him until it reached the edge of a rock hanging over the water. But once at that point it would stop retreating. It would just let him approach and catch it, rather than flee into the water. And here we come to the infamous iguana chucking scene of the Voyage of the Beagle. Darwin writes, I threw one several times as far as I could into a dep pool left by the retiring tide, but it invariably returned in a direct line to the spot where I stood. It swam near the bottom with a very graceful and rapid movement, and occasionally aided itself over the uneven ground with its feet. As soon as it arrived near the edge, but still being underwater, it tried to conceal itself in the tufts of seaweed, or it entered some crevice. As soon as it thought the danger was past, it crawled out on the dry rocks and shuffled away as quickly as it could. I several times caught this same lizard by driving it down to a point, and though possessed of such perfect powers of diving and swimming, nothing would induce it to enter the water, And as often as I threw it in, it returned in the manner above described. Now, this is indeed a really odd bit of behavior, right.

But after introducing them, Darwin goes on to describe the animals in detail, describing their movements with a strange mix of admiration and disgust. So here's what he says. Quote. When in the water, this lizard swims with perfect ease and quickness by a serpentine movement of its body and flattened tail, the legs being motionless and closely collapsed on its sides. A seman on board sank one with a heavy weight attached to it, thinking thus to kill it directly, But when an hour afterwards he drew up the line, it was quite active. Their limbs and strong claws are admirably adapted for crawling over the rugged and fissured masses of lava which everywhere form the coast. In such situations, a group of six or seven of these hideous reptiles may oftentimes be seen on the black rocks a few feet above the surf, basking in the sun with outstretched legs. And then he goes on to note a strange, perplexing, almost contradictory observation about their behavior. So, while the iguanas go to sea in order to forage, that's how they make a living, They swim out in the water, get the algae and eat it. He found that he could not scare them into the water. If he approached one, it would back away from him until it reached the edge of a rock hanging over the water. But once at that point it would stop retreating. It would just let him approach and catch it, rather than flee into the water. And here we come to the infamous iguana chucking scene of the Voyage of the Beagle. Darwin writes, I threw one several times as far as I could into a dep pool left by the retiring tide, but it invariably returned in a direct line to the spot where I stood. It swam near the bottom with a very graceful and rapid movement, and occasionally aided itself over the uneven ground with its feet. As soon as it arrived near the edge, but still being underwater, it tried to conceal itself in the tufts of seaweed, or it entered some crevice. As soon as it thought the danger was past, it crawled out on the dry rocks and shuffled away as quickly as it could. I several times caught this same lizard by driving it down to a point, and though possessed of such perfect powers of diving and swimming, nothing would induce it to enter the water, And as often as I threw it in, it returned in the manner above described. Now, this is indeed a really odd bit of behavior, right.

Yeah, so it would seem. Now, before we get into that, I want to just mention I want to make two comments about Darwin's riding here. First of all, I do get the impression that perhaps Darwin was not a cat person or had a cat, because like, this is the same, the same situation I think any cat owner can attest to. It's like I tried to put the cat where I wanted it to be, and it did not want to be there. So strange. But on the other hand, I do love the part where he talks about how graceful they are in the water, because that is also a huge tree getting to watch these lizards swim about, because it's I mean, it's unlike anything you see with any other species on the planet. There's this graceful, indeed serpentine movement to them. There whatever awkwardness you might observe on the land is not present in the water, and it's it's like watching a strange aquatic little dragon move about.

Yeah, so it would seem. Now, before we get into that, I want to just mention I want to make two comments about Darwin's riding here. First of all, I do get the impression that perhaps Darwin was not a cat person or had a cat, because like, this is the same, the same situation I think any cat owner can attest to. It's like I tried to put the cat where I wanted it to be, and it did not want to be there. So strange. But on the other hand, I do love the part where he talks about how graceful they are in the water, because that is also a huge tree getting to watch these lizards swim about, because it's I mean, it's unlike anything you see with any other species on the planet. There's this graceful, indeed serpentine movement to them. There whatever awkwardness you might observe on the land is not present in the water, and it's it's like watching a strange aquatic little dragon move about.

Well, I think it's also about the way that like they anatomically modify themselves to move in the water versus on land, because as Darwin says, they collapse their legs to the side and almost become a snake in the water.

Well, I think it's also about the way that like they anatomically modify themselves to move in the water versus on land, because as Darwin says, they collapse their legs to the side and almost become a snake in the water.

Yeah, but with their heads up in a way that like you wouldn't mistake it for a snake. Like the profile of the swimming marine iguana is unlike anything certainly that I've ever seen. So it really stands out in your mind, like your mind instantly is identifying that this is something different, This is something novel.

Yeah, but with their heads up in a way that like you wouldn't mistake it for a snake. Like the profile of the swimming marine iguana is unlike anything certainly that I've ever seen. So it really stands out in your mind, like your mind instantly is identifying that this is something different, This is something novel.

I agree, and having seen not in person but seen plenty of video of it. They are beautiful when they're swimming. But to come back to this odd behavior, so Darwin says, Okay, these things they go in the water all the time, that's how they eat. They go down in the water, they eat, they come back. How come I can't scare one into the water or get it to stay in the water by throwing it in. I throw it in, the water just comes back out. Darwin comes up with the guests about wyat acts this way. He says, quote, perhaps this singular piece of apparent stupidity may be accounted for by the circumstance that this reptile has no enemy whatever on shore, whereas it's at sea it must often fall prey to the numerous sharks, hence probably by a fixed and hereditary instinct that the shore is its place of safety. Whatever the emergency may be, it there takes refuge. So, okay, that's an interesting guess. He says. It has natural predators in the water, but not on land, so it just feels safer on land, even if here I am threatening it on land, because it's just acting out of instinct.

I agree, and having seen not in person but seen plenty of video of it. They are beautiful when they're swimming. But to come back to this odd behavior, so Darwin says, Okay, these things they go in the water all the time, that's how they eat. They go down in the water, they eat, they come back. How come I can't scare one into the water or get it to stay in the water by throwing it in. I throw it in, the water just comes back out. Darwin comes up with the guests about wyat acts this way. He says, quote, perhaps this singular piece of apparent stupidity may be accounted for by the circumstance that this reptile has no enemy whatever on shore, whereas it's at sea it must often fall prey to the numerous sharks, hence probably by a fixed and hereditary instinct that the shore is its place of safety. Whatever the emergency may be, it there takes refuge. So, okay, that's an interesting guess. He says. It has natural predators in the water, but not on land, so it just feels safer on land, even if here I am threatening it on land, because it's just acting out of instinct.

Yeah, yeah, it would seem to be a decent theory. And indeed on land that nothing really messes with them except when they're smaller. And when they're smaller there you know, like and this is the case with a number of iguanas and lizards, like until they reach a certain size, they're on the menu for various other creatures and birds and whatnot. But once they reach a certain maturity. Yeah, they can just bask where they want. Nothing's going to mess with them.

Yeah, yeah, it would seem to be a decent theory. And indeed on land that nothing really messes with them except when they're smaller. And when they're smaller there you know, like and this is the case with a number of iguanas and lizards, like until they reach a certain size, they're on the menu for various other creatures and birds and whatnot. But once they reach a certain maturity. Yeah, they can just bask where they want. Nothing's going to mess with them.

Yeah, well, at least in the ancestral environment of the Glasogos. Now introduced to dogs and pigs and all that stuff that humans brought there will prey on them. So I decided to follow up on this and see has there been any sub sequent research about this behavior in marine iguanas that could confirm or deny Darwin's guess about the evolutionary reasoning there. And I found a paper that addresses exactly this topic. It is by Edmund S. Hobson called Remarks on Aquatic Habitats of the Galapagos Marine Iguana, including submergence times, cleaning, symbiosis, and the Shark Threat. This was published in a journal called Copeia in nineteen sixty nine, and it seems that sharks do occasionally eat the iguanas as Darwin guest. A report of the contents of shark's stomachs in nineteen oh three by Heller did find some marine iguanas in there, but Hobson thinks that the threat to iguanas by sharks is mostly exaggerated, given that he and his colleagues directly observed iguanas and sharks swimming in the same waters side by side, and he says almost all the time they just ignore one another entirely. To read from Hobson quote to the contrary, the general situation finds sharks swimming slowly among smaller fishes with no overt sign that they regard these animals as prey. Certainly, sharks are efficient predators when they do attack, but situations evoking attack are relatively infrequent. At Narborough Island, I saw white tipped sharks and a gray shark pass within a few meters of surface swimming iguanas, with no indication that they regarded the iguanas as prey. George Barlow and I made a similar observation involving a large hammer head at Hood Island. So if it's not a fear of sharks, what explains this behavior?

Yeah, well, at least in the ancestral environment of the Glasogos. Now introduced to dogs and pigs and all that stuff that humans brought there will prey on them. So I decided to follow up on this and see has there been any sub sequent research about this behavior in marine iguanas that could confirm or deny Darwin's guess about the evolutionary reasoning there. And I found a paper that addresses exactly this topic. It is by Edmund S. Hobson called Remarks on Aquatic Habitats of the Galapagos Marine Iguana, including submergence times, cleaning, symbiosis, and the Shark Threat. This was published in a journal called Copeia in nineteen sixty nine, and it seems that sharks do occasionally eat the iguanas as Darwin guest. A report of the contents of shark's stomachs in nineteen oh three by Heller did find some marine iguanas in there, but Hobson thinks that the threat to iguanas by sharks is mostly exaggerated, given that he and his colleagues directly observed iguanas and sharks swimming in the same waters side by side, and he says almost all the time they just ignore one another entirely. To read from Hobson quote to the contrary, the general situation finds sharks swimming slowly among smaller fishes with no overt sign that they regard these animals as prey. Certainly, sharks are efficient predators when they do attack, but situations evoking attack are relatively infrequent. At Narborough Island, I saw white tipped sharks and a gray shark pass within a few meters of surface swimming iguanas, with no indication that they regarded the iguanas as prey. George Barlow and I made a similar observation involving a large hammer head at Hood Island. So if it's not a fear of sharks, what explains this behavior?

Well, if I would a venture a guess, I'd say it has to do with temperature, that they're thermic reasons at play here.

Well, if I would a venture a guess, I'd say it has to do with temperature, that they're thermic reasons at play here.

Great thinking, and this is exactly what Hobson concludes. Hobson argues that the best explanation for this apparently weird behavior observed by Darwin is that the water's cold, you know, they have to go in there to get food, but they don't want to spend any more time in there than they have to because it's cold and they're reptiles. To read from Hobson, citing another researcher named Bartholomew quote. Bartholomew in nineteen sixty six offered a more plausible explanation after noting that iguanas basking on the rocks ashore have a preferred body temperature of thirty five to thirty seven degrees celsius, over ten degrees celsius above that of the sea. He suggested that iguanas which are taken from the rocks and thrown into the water immediately return to land simply because they are reluctant to cool off. And I love this explanation. It also does seem plausible to me. But I love this because it highlights something about human thinking that even Darwin himself was not immune to. And Rob, I think you'll know exactly what I'm talking about here. When humans are trying to come up with explanations for an animal behavior or a feature of an animal body or something, I think humans are way too quick to jump to two types of explanations, those involving mating and those involving predation, sex and violence. Just in our brains, sex and violence are more salient explanations than all kinds of other pressures that exist in nature and do drive animal body plans and animal behaviors. Things having to do with just base physical realities of the world, like maintaining body temperature, thermoregulation, access to oxygen, all kinds of things like that that explain tons about the natural world. It's just our brains just don't jump to those things as quickly when we're looking for a why.

Great thinking, and this is exactly what Hobson concludes. Hobson argues that the best explanation for this apparently weird behavior observed by Darwin is that the water's cold, you know, they have to go in there to get food, but they don't want to spend any more time in there than they have to because it's cold and they're reptiles. To read from Hobson, citing another researcher named Bartholomew quote. Bartholomew in nineteen sixty six offered a more plausible explanation after noting that iguanas basking on the rocks ashore have a preferred body temperature of thirty five to thirty seven degrees celsius, over ten degrees celsius above that of the sea. He suggested that iguanas which are taken from the rocks and thrown into the water immediately return to land simply because they are reluctant to cool off. And I love this explanation. It also does seem plausible to me. But I love this because it highlights something about human thinking that even Darwin himself was not immune to. And Rob, I think you'll know exactly what I'm talking about here. When humans are trying to come up with explanations for an animal behavior or a feature of an animal body or something, I think humans are way too quick to jump to two types of explanations, those involving mating and those involving predation, sex and violence. Just in our brains, sex and violence are more salient explanations than all kinds of other pressures that exist in nature and do drive animal body plans and animal behaviors. Things having to do with just base physical realities of the world, like maintaining body temperature, thermoregulation, access to oxygen, all kinds of things like that that explain tons about the natural world. It's just our brains just don't jump to those things as quickly when we're looking for a why.

Yeah, I think modern reptile enthusiasts, especially any who have been engaged in keeping of reptiles, they'll be pretty quick to tell you, Oh, yeah, temperature is important, temperature regulation. You know, the lizards, snakes, they want their warm places, and they're certainly going to realize that. But yeah, this is an easy, easy trap to fall into. I should also say I did go into the water in the Galapagos snorkeling once, and it is, to me a non iguana, quite cold. So I can in some way at least understand how they feel about it.

Yeah, I think modern reptile enthusiasts, especially any who have been engaged in keeping of reptiles, they'll be pretty quick to tell you, Oh, yeah, temperature is important, temperature regulation. You know, the lizards, snakes, they want their warm places, and they're certainly going to realize that. But yeah, this is an easy, easy trap to fall into. I should also say I did go into the water in the Galapagos snorkeling once, and it is, to me a non iguana, quite cold. So I can in some way at least understand how they feel about it.

Yeah, so Mark me is convinced I think that iguana kept swimming back and crawling out of the water after Darwin threw it in because it was getting cold and it wanted to it wanted to warm back up on the rocks.

Yeah, so Mark me is convinced I think that iguana kept swimming back and crawling out of the water after Darwin threw it in because it was getting cold and it wanted to it wanted to warm back up on the rocks.

Yeah, and let I say, they're pretty chill, but they're like, no, it's too cold. I would like to get out, and he's like, I'm throwing you back in. He's like, too cold. I wish to get out. It's not time. It's not time. I will get in the water when I am warmed up enough to do so. Now getting into a little bit about the evolution of the marine reptiles, it's very fascinating, especially again thinking of them as this really largely singular occurrence in the modern world. So I was looking at a few different sources. One of these was Marine Reptiles by Resmussen at Hall from twenty eleven published in Peel one. They point out here that lizards make up sixty percent of all reptiles, but very few lizard species compared to say, turtles and snakes, are present in our oceans. And this isn't getting so much into the issue of prehistoric aquatic reptiles, which do include extinct squa mats, like the mosasaur. The mososaurs, which were actually distant relatives of modern iguanas and monitor lizards, were pretty fascinating in and of themselves. They were gigantic, They reached links of up to twelve meters or forty feet. They swam in earth oceans roughly sixty six million years ago. They hunted other marine reptiles, and it's possible they gave birth to live young in the water, though I'm not sure this is certain. There's various studies out there about possible egg finds of the mosasaurs, but it's worth mentioning here to drive home the difference between today's marine reptile and those of the past, and especially you know, thinking about sea turtles, thinking to about the marine iguana. These are animals that, to varying degrees, are great in the water, but they still must return to shore to complete some vital stage of their life, certainly with sea turtles. With the marine iguana, it's more living on the shore but then going into the water to graze and feed. Yeah, so of extent lizards that are in any way aquatic, there are only a few extreme examples, and this includes the Western Pacific mangrove monitor, which is a carnivore. But as the authors here point out, the Galapagos marine iguana is the most aquatic of all extents lizards. It basks, breeds and lays eggs on land, et cetera, but it has to go into the water to feed. It is, by other definitions, the only squaw mate that's actually able to exploit the re sources of the ocean in a meaningful way. So the aforementioned monitor lizard, for example, can catch fish, but it also feeds on terrestrial meats as well. I should also note that there are other iguanas on the Glabgos Island islands, to be sure, including seven smaller species and three species of land iguanas in the genus Conolophus. They include the beautiful and rare Galapagos pink iguana, which is a most special creature. Included a picture of this for you, Joe and everyone out there. You should look up a picture of the Galapagos pink iguana. This is not something I got to see when I was there, because it lives in a very remote part of the islands. Not not even even locals don't usually get to see this creature.

Yeah, and let I say, they're pretty chill, but they're like, no, it's too cold. I would like to get out, and he's like, I'm throwing you back in. He's like, too cold. I wish to get out. It's not time. It's not time. I will get in the water when I am warmed up enough to do so. Now getting into a little bit about the evolution of the marine reptiles, it's very fascinating, especially again thinking of them as this really largely singular occurrence in the modern world. So I was looking at a few different sources. One of these was Marine Reptiles by Resmussen at Hall from twenty eleven published in Peel one. They point out here that lizards make up sixty percent of all reptiles, but very few lizard species compared to say, turtles and snakes, are present in our oceans. And this isn't getting so much into the issue of prehistoric aquatic reptiles, which do include extinct squa mats, like the mosasaur. The mososaurs, which were actually distant relatives of modern iguanas and monitor lizards, were pretty fascinating in and of themselves. They were gigantic, They reached links of up to twelve meters or forty feet. They swam in earth oceans roughly sixty six million years ago. They hunted other marine reptiles, and it's possible they gave birth to live young in the water, though I'm not sure this is certain. There's various studies out there about possible egg finds of the mosasaurs, but it's worth mentioning here to drive home the difference between today's marine reptile and those of the past, and especially you know, thinking about sea turtles, thinking to about the marine iguana. These are animals that, to varying degrees, are great in the water, but they still must return to shore to complete some vital stage of their life, certainly with sea turtles. With the marine iguana, it's more living on the shore but then going into the water to graze and feed. Yeah, so of extent lizards that are in any way aquatic, there are only a few extreme examples, and this includes the Western Pacific mangrove monitor, which is a carnivore. But as the authors here point out, the Galapagos marine iguana is the most aquatic of all extents lizards. It basks, breeds and lays eggs on land, et cetera, but it has to go into the water to feed. It is, by other definitions, the only squaw mate that's actually able to exploit the re sources of the ocean in a meaningful way. So the aforementioned monitor lizard, for example, can catch fish, but it also feeds on terrestrial meats as well. I should also note that there are other iguanas on the Glabgos Island islands, to be sure, including seven smaller species and three species of land iguanas in the genus Conolophus. They include the beautiful and rare Galapagos pink iguana, which is a most special creature. Included a picture of this for you, Joe and everyone out there. You should look up a picture of the Galapagos pink iguana. This is not something I got to see when I was there, because it lives in a very remote part of the islands. Not not even even locals don't usually get to see this creature.

The first thing that popped into my head is it looks kind of like a hot dog.

The first thing that popped into my head is it looks kind of like a hot dog.

Yeah, yeah, it's you know, it's it's it's it's a specially it's an iguana pink. But yeah, these are these are rare and beautiful creatures. But again, the marine iguana is the real standout here. The other iguanas are a lot of fun to watch too, if you if you visit, but yeah, the marine iguana is special. The average adult is around one point two meters in length, so they're not huge, and they're found on virtually every island of the Galapagos. So coming back to the question, how did any of these lizards get to the Far Flow and Galapagos islands, The answer, according to Resmussen at all is probably that they're all related to iguanas from South America that were washed from the South American mainland, again perhaps by river floods, and carried out to the Galapagos. And again this is where the Galapagos's isolation yet closer proximity to a continental mainland comes into play. The theory is also in part supported by the fact that as distinct as the four bigger iguanas of the Galapagos Islands, including the marine iguana are They are closely related and they actually can breed with one another to produce hybrids, so hybrids have been reported according to Resmussen. At all, the marine iguanas spend quite a bit of time in the water, though foraging for their food. As adults, they feed almost exclusively on the red and green algae. It's been pointed out they're not above at least trying out the odds scrap of this, that or the other, and perhaps that accounts for the crab claw that Charles Darwin reported. And there's at least one population of the marine iguanas that has been observed to supplement their diet with land plants. But for the most part, their hindgut has evolved to thrive on the algae like they're bound to the algae. This is not just a this is not just a lifestyle choice at this point, and their bodies have adapted in other key ways as well to allow this marine diet due to the considerable selection pressure that's been applied to them, which is quite literally the selection pressure of being cast upon a resource depleted island. So we mentioned their flattened tail that's one of the adaptations. And it's not like you don't find flattened tails and other lizard species, but this is clearly something that seems to help out there swimming. They also have limited webbing on their feet, which I saw kind of two different takes on this in the literature I was looking at. On one hand, there's the argument like, yeah, it's partially web feet, this is going to help them swim, But others say, well, the webbing is not that extensive. It maybe helps a little bit, but let's not overstress its importance.

Yeah, yeah, it's you know, it's it's it's it's a specially it's an iguana pink. But yeah, these are these are rare and beautiful creatures. But again, the marine iguana is the real standout here. The other iguanas are a lot of fun to watch too, if you if you visit, but yeah, the marine iguana is special. The average adult is around one point two meters in length, so they're not huge, and they're found on virtually every island of the Galapagos. So coming back to the question, how did any of these lizards get to the Far Flow and Galapagos islands, The answer, according to Resmussen at all is probably that they're all related to iguanas from South America that were washed from the South American mainland, again perhaps by river floods, and carried out to the Galapagos. And again this is where the Galapagos's isolation yet closer proximity to a continental mainland comes into play. The theory is also in part supported by the fact that as distinct as the four bigger iguanas of the Galapagos Islands, including the marine iguana are They are closely related and they actually can breed with one another to produce hybrids, so hybrids have been reported according to Resmussen. At all, the marine iguanas spend quite a bit of time in the water, though foraging for their food. As adults, they feed almost exclusively on the red and green algae. It's been pointed out they're not above at least trying out the odds scrap of this, that or the other, and perhaps that accounts for the crab claw that Charles Darwin reported. And there's at least one population of the marine iguanas that has been observed to supplement their diet with land plants. But for the most part, their hindgut has evolved to thrive on the algae like they're bound to the algae. This is not just a this is not just a lifestyle choice at this point, and their bodies have adapted in other key ways as well to allow this marine diet due to the considerable selection pressure that's been applied to them, which is quite literally the selection pressure of being cast upon a resource depleted island. So we mentioned their flattened tail that's one of the adaptations. And it's not like you don't find flattened tails and other lizard species, but this is clearly something that seems to help out there swimming. They also have limited webbing on their feet, which I saw kind of two different takes on this in the literature I was looking at. On one hand, there's the argument like, yeah, it's partially web feet, this is going to help them swim, But others say, well, the webbing is not that extensive. It maybe helps a little bit, but let's not overstress its importance.

Well, I'm no marine iguana expert, but it seems to me, at least when I've seen images of them swimming, it doesn't seem like they paddle with their feet much at all that I recall, but maybe they do sometimes.

Well, I'm no marine iguana expert, but it seems to me, at least when I've seen images of them swimming, it doesn't seem like they paddle with their feet much at all that I recall, but maybe they do sometimes.

Something that everyone agrees on, though, is that their claws have become more powerful to allow them to grip the rocks and the surf during feeding. And this is certainly key because if you're observing one from the shore, or if you're looking at images or footage of them, or if you're snorkeling, you get to see one underwater. I did not get to see one underwater. Firsthand. But either way, when they're feeding, they're often in an area where the the you know, the surf is disrupting them and would make it difficult to feed if they were not able to hold on and latch on. And then of course when they get in or out of the surf, they're going to need to keep from being swept up anyway. So yeah, they got to have those powerful claws to aid them.