WEBVTT - From the Vault: The Remarkable Beaver, Part 1 0:00:06.320 --> 0:00:08.800 Hey, welcome to Stuff to Blow Your Mind. My name 0:00:08.880 --> 0:00:09.440 is Robert. 0:00:09.280 --> 0:00:12.400 Lamb and I am Joe McCormick. And it's Saturday, so 0:00:12.480 --> 0:00:14.720 we're going into the vault for an older episode of 0:00:14.720 --> 0:00:18.040 Stuff to Blow Your Mind. This one originally published May eighteenth, 0:00:18.120 --> 0:00:21.480 twenty twenty three, and it is part one of our 0:00:21.520 --> 0:00:26.119 series on the beaver, a truly remarkable animal, far more 0:00:26.160 --> 0:00:28.400 strange and amazing than you might imagine. 0:00:28.560 --> 0:00:30.800 Yeah, so have you skipped it the first time around, 0:00:30.840 --> 0:00:33.199 thinking I don't want to hear about beavers. Beavers are boring. Well, 0:00:33.200 --> 0:00:37.080 you were wrong. Beavers are exciting and allow us to 0:00:37.360 --> 0:00:40.640 prove this to you in this episode and the following. 0:00:43.520 --> 0:00:47.519 Welcome to Stuff to Blow your Mind, a production of iHeartRadio. 0:00:53.600 --> 0:00:56.360 Hey, welcome to Stuff to Blow your Mind. My name 0:00:56.480 --> 0:01:00.639 is Robert Lamb and I'm Joe McCormick. We've covered numerous 0:01:00.720 --> 0:01:05.080 examples of this before, but obviously, in days before photography 0:01:05.280 --> 0:01:10.040 and videography, one had to depend on illustrations and written 0:01:10.080 --> 0:01:14.080 descriptions to convey the reality of an organism, you know, 0:01:14.200 --> 0:01:17.959 be it a bird or a fish, what have you. 0:01:18.720 --> 0:01:21.840 But this is especially true for creatures that lived in 0:01:21.959 --> 0:01:25.880 lands beyond your direct experience. You know, what are the 0:01:26.319 --> 0:01:29.319 what are the mammals, what are the birds? Like on 0:01:29.440 --> 0:01:31.440 another continent. Well, you have to send people out in 0:01:31.440 --> 0:01:32.760 the world. They can, you know, to a certain extent. 0:01:32.800 --> 0:01:35.280 They can bring specimens back. Certainly, they can bring parts 0:01:35.280 --> 0:01:39.080 of specimens back, but it's those ill in some cases, 0:01:39.880 --> 0:01:44.560 but it's those illustrations that really bring things alive. Now, 0:01:44.920 --> 0:01:48.000 certainly there are some fine examples of naturalist illustration out there, 0:01:48.080 --> 0:01:51.640 especially from recent centuries. I mean there's some gorgeous, like 0:01:51.680 --> 0:01:55.000 you say, like Audubond illustrations and paintings that sort of thing. 0:01:55.520 --> 0:01:58.320 But there are also countless examples, and we've touched on 0:01:58.360 --> 0:02:02.760 these before in the show of rough or drawings, drawings 0:02:02.760 --> 0:02:04.280 that feel like, you know, there's been a game of 0:02:04.280 --> 0:02:08.720 telephone at play. And this is especially the case for 0:02:08.800 --> 0:02:13.960 examples found in various bestiaries and medieval manuscripts, among other places. 0:02:14.440 --> 0:02:18.320 And when we think of such misconstrued animals, you know, 0:02:18.320 --> 0:02:19.800 what do we tend to think about? You know, we 0:02:19.840 --> 0:02:24.000 think about the rhino, We think about the lion, the whale, 0:02:24.120 --> 0:02:28.600 the elephant, you know, great animals, apex, predators, and megafauna. 0:02:29.040 --> 0:02:31.400 But in this episode, in the next episode, at the 0:02:31.480 --> 0:02:34.320 very least, we're going to get into another creature that 0:02:34.360 --> 0:02:39.800 has also experienced extreme inaccuracy in historic illustration, and that 0:02:40.000 --> 0:02:43.640 is the common beaver. Based on just some of the 0:02:43.680 --> 0:02:47.120 images we've been looking at, a beaver might well be 0:02:47.560 --> 0:02:50.079 a kind of strange dog or a pig with a 0:02:50.440 --> 0:02:53.040 with perhaps a fish tail on its body, you know, 0:02:53.080 --> 0:02:56.200 a real hybrid feeling like it is, almost like it's 0:02:56.240 --> 0:03:02.200 a strange like dog mermaid. It might be in almost 0:03:02.240 --> 0:03:06.360 all respects a deer, like a creature with long legs 0:03:06.400 --> 0:03:11.359 and hooves. And it may also look like a strange 0:03:11.360 --> 0:03:15.519 and confused rodent with a great button seam running down 0:03:15.560 --> 0:03:19.880 its chest. It may even look like a weirdly serpentine lion. 0:03:20.520 --> 0:03:25.560 So Rob has been sharing medieval and Renaissance illustrations of 0:03:25.560 --> 0:03:29.320 beavers with me for a couple of days now, and 0:03:29.639 --> 0:03:31.640 I really do love all of them. But I do 0:03:31.680 --> 0:03:33.480 think the one I like the most is the one 0:03:33.480 --> 0:03:37.080 that's just straight up a deer with hooves, except it 0:03:37.160 --> 0:03:41.160 has razor blades for teeth, just like the rectangular razor blades. 0:03:41.720 --> 0:03:43.560 Yeah, yeah, this one. I had to go deep around 0:03:43.560 --> 0:03:46.080 this one because I was It initially came up in 0:03:46.120 --> 0:03:48.280 an image search and you know, I think it was 0:03:48.280 --> 0:03:50.040 maybe on a pinterest or something. I was like, I 0:03:50.080 --> 0:03:52.520 can't trust this. But I eventually looked it up in 0:03:52.600 --> 0:03:58.000 the catalog of illuminated manuscripts and it is a Northern 0:03:58.080 --> 0:04:04.440 Italian illustration from somewhere around the year fourteen forty. And yeah, 0:04:04.480 --> 0:04:07.320 it just looks like a It is labeled as a beaver, 0:04:07.720 --> 0:04:10.320 but it is in all respects a deer. So I 0:04:10.400 --> 0:04:13.720 was just really astounded, like here, especially as an image, 0:04:14.120 --> 0:04:18.960 that it not only gets the form wrong regarding the 0:04:19.040 --> 0:04:22.080 target organism, it gets everything about like the energy of 0:04:22.120 --> 0:04:24.280 the creature wrong, you know, because it's it's one thing 0:04:24.279 --> 0:04:26.120 if you have a depiction of a rhino that okay, 0:04:26.160 --> 0:04:28.599 it's like a big armor plated thing with four legs. 0:04:28.640 --> 0:04:31.080 It's like, all right, I mean that's it's an extravagant 0:04:31.160 --> 0:04:35.119 version of the truth. But this, it's like, how wrong 0:04:35.240 --> 0:04:36.560 did this game of telephone go? 0:04:37.160 --> 0:04:40.640 Right? With the right? You like, with deerors rhinoceros, you 0:04:40.680 --> 0:04:45.279 can see that beginning as a rhinoceros, but with embellishments, yes, 0:04:45.760 --> 0:04:48.000 But with the beaver, it's like, oh, I'm sorry, did 0:04:48.000 --> 0:04:50.640 you say beaver? I thought you asked for a depiction 0:04:50.839 --> 0:04:53.400 of a of a lion with a snake neck biting 0:04:53.440 --> 0:04:54.360 its own genitals. 0:04:54.920 --> 0:04:57.040 That's right, because and this is this is something we'll 0:04:57.040 --> 0:05:00.200 probably get into mostly in the next episode, But there 0:05:00.240 --> 0:05:04.760 is this pervasive myth that existed for a very long 0:05:04.800 --> 0:05:07.920 time that when pursued by hunters, a male beaver would 0:05:07.960 --> 0:05:10.360 chew off its own testicles. And so many of these images. 0:05:10.800 --> 0:05:14.840 Be your creature more dog or catlike, or or actually 0:05:14.880 --> 0:05:17.240 just a deer with razor sharp teeth, it is often 0:05:17.279 --> 0:05:21.599 depicted nine at its testicles. That at least we have 0:05:21.720 --> 0:05:24.400 some answers for in the next episode where that idea 0:05:24.480 --> 0:05:26.800 comes from and why it's so pervasive. 0:05:26.760 --> 0:05:28.479 Right, So you've got to stick around for next time 0:05:28.520 --> 0:05:28.960 to hear that. 0:05:29.680 --> 0:05:33.440 Yeah, so let's start with what we know. Let's start 0:05:33.440 --> 0:05:36.000 with the reality. We're gonna start by talking about just 0:05:36.080 --> 0:05:40.000 basic beaver anatomy and behavior. And I probably don't have 0:05:40.080 --> 0:05:43.000 to tell most listeners out there what a beaver looks like. 0:05:43.120 --> 0:05:46.520 I mean, for starters, like, we have images all over 0:05:46.520 --> 0:05:49.520 the place of them, we have documentary footage. Many of 0:05:49.560 --> 0:05:53.440 you can go and see a live beaver at least 0:05:53.440 --> 0:05:56.120 in some sort of like a zoo environment, or you 0:05:56.200 --> 0:05:58.520 have seen them in the past. But on the other 0:05:58.600 --> 0:06:00.599 side of the coin, it's, like I said, still kind 0:06:00.600 --> 0:06:02.320 of have to tell you what a beaver looks like 0:06:02.839 --> 0:06:05.080 because the beaver is kind of in the same category 0:06:05.120 --> 0:06:07.680 as the spouting whale, as we discussed in some of 0:06:07.720 --> 0:06:10.599 our recent whale episodes, those particularly the ones on spouting 0:06:10.640 --> 0:06:16.960 and spouts. Because despite all this access to actual, solid 0:06:17.000 --> 0:06:20.080 documentary footage of the beaver, we still have this rich 0:06:20.160 --> 0:06:23.479 history of cartoon depictions of beavers that inevitably cloud our 0:06:23.560 --> 0:06:24.840 understanding of the creatures. 0:06:25.120 --> 0:06:27.200 I mean, I think you get a fairly accurate mental 0:06:27.240 --> 0:06:30.560 picture if you just cross a squirrel with a grizzly bear. 0:06:31.040 --> 0:06:34.080 You know, you mash those two up your most of 0:06:34.120 --> 0:06:36.320 the way there. But while that does get you sort 0:06:36.360 --> 0:06:39.880 of the shape the outline, right, that does not tell 0:06:39.880 --> 0:06:42.080 you everything you need to know about beavers. Beavers are 0:06:42.240 --> 0:06:46.680 much stranger and more beautiful than I realized. 0:06:47.240 --> 0:06:51.040 Yeah. Yeah, there's a lot of weird and wonderful aspects 0:06:51.080 --> 0:06:55.200 to their morphology, to their behavior, and a lot of 0:06:55.240 --> 0:06:57.880 this is stuff that our popular conceptions of the beaver 0:06:58.600 --> 0:07:00.680 don't get into. I mean, you know, they do get 0:07:00.680 --> 0:07:02.520 some of the things right, you know, the basic shape 0:07:02.560 --> 0:07:04.760 of the beaver is far better in cartoon than it 0:07:04.839 --> 0:07:07.840 is in many of these eliminated manuscripts. You know, some 0:07:07.920 --> 0:07:10.240 things hold up. Obviously, beavers are not going to sell 0:07:10.280 --> 0:07:12.960 you out to the White Witch. That's absolutely true. 0:07:13.680 --> 0:07:14.200 So C. S. 0:07:14.280 --> 0:07:16.120 Lewis was right on that count, even if he got 0:07:16.120 --> 0:07:19.840 the whole diet of the beaver wrong, because in Narnia, 0:07:19.920 --> 0:07:22.920 apparently beavers like to eat fish and chips. That's not 0:07:23.040 --> 0:07:26.400 happening in the actual natural world. 0:07:27.000 --> 0:07:29.040 On the other hand, I will say, there is the 0:07:29.160 --> 0:07:31.800 kind of food and organism usually seeks out to eat 0:07:31.840 --> 0:07:35.320 in its environment, versus what an animal will eat if 0:07:35.360 --> 0:07:37.720 given the opportunity. I kind of wonder. I feel like 0:07:37.720 --> 0:07:41.280 if you gave a beaver a basket of chips and 0:07:41.280 --> 0:07:43.360 some malt vinegar, I don't know they might get into that. 0:07:44.280 --> 0:07:46.240 All right, Well, let's start with the basics here. So 0:07:46.320 --> 0:07:50.280 beavers are rodents, and are in fact the second largest 0:07:50.320 --> 0:07:55.240 extent rodent, surpassed only by the mighty capybara. Beavers can 0:07:55.280 --> 0:07:58.720 weigh up to fifty kilograms or one hundred and ten pounds. 0:07:59.280 --> 0:08:01.920 There are two extant species of beaver. There's the North 0:08:01.960 --> 0:08:07.480 American beaver or castor canadensis and the Eurasian beaver caste 0:08:07.600 --> 0:08:13.760 or fiber. But the Castoridae family includes some impressive extinct 0:08:13.880 --> 0:08:17.240 species as well. In fact, there were giant beavers that 0:08:17.320 --> 0:08:21.400 lived during the Pleistocene, reaching weights of up to one 0:08:21.440 --> 0:08:24.000 hundred and twenty five kilograms or two hundred and seventy 0:08:24.040 --> 0:08:27.120 six pounds, So that is more than twice as big 0:08:27.480 --> 0:08:31.000 as extant beavers. Though I was reading they seem to 0:08:31.040 --> 0:08:35.640 have had smaller brains, among other morphological differences. But yeah, 0:08:35.679 --> 0:08:38.760 so they were bigger, and you know, maybe to some 0:08:38.800 --> 0:08:41.439 extent they didn't have to or had not yet developed 0:08:41.960 --> 0:08:45.720 these very impressive behaviors and abilities that we'll get into 0:08:45.720 --> 0:08:49.080 concerning modern beavers. Now, one note on these guys. They 0:08:49.080 --> 0:08:53.000 were still smaller than the fifteen hundred kilogram or thirty 0:08:53.040 --> 0:08:58.679 three hundred pound giant pacaranas of South America. Extant pacaranas 0:08:58.880 --> 0:09:01.680 only get up to light thirty three pounds or fifteen kilograms, 0:09:01.800 --> 0:09:03.920 and they can still be found in the western Amazonian 0:09:04.040 --> 0:09:08.280 River basin. But the giant ones, they were pretty massive. 0:09:08.640 --> 0:09:12.680 A lot of rodents of unusual size in freehistory, all. 0:09:12.640 --> 0:09:15.600 Right, So no beavers today in that territory, but beavers 0:09:15.600 --> 0:09:16.800 can still get pretty chunky. 0:09:17.360 --> 0:09:19.960 That's right. Yeah, they're pretty big, And this is like 0:09:19.960 --> 0:09:24.080 a fact. I frequently forget that they're the second biggest rodent. 0:09:24.360 --> 0:09:26.360 The kappy bear is easy to remember, but it's sometimes 0:09:26.400 --> 0:09:28.679 it's easy to forget who's coming in second. Now, it's 0:09:28.720 --> 0:09:33.240 extremely important to note that beavers are semi aquatic, having 0:09:33.240 --> 0:09:37.480 evolved to thrive in various freshwater habitats, so a number 0:09:37.520 --> 0:09:39.560 of the things we're going to be discussing about them 0:09:40.240 --> 0:09:43.280 line up with their habitat. For instance, they can hold 0:09:43.280 --> 0:09:47.840 their breath for fifteen minutes. They have transparent third eyelids 0:09:47.920 --> 0:09:51.520 called nicitating membranes to aid them in their swims, much 0:09:51.600 --> 0:09:56.520 like manatees. They also famously have long, flat black tails. 0:09:56.559 --> 0:09:59.560 We know this from the cartoons obviously, and these aid 0:09:59.559 --> 0:10:02.480 them in their swimming, but they can also use them 0:10:02.520 --> 0:10:05.360 to sound an alarm by slapping the water slapping the 0:10:05.360 --> 0:10:07.960 surface of the water, and they also use them to 0:10:08.080 --> 0:10:12.120 balance when they're carrying wood or other loads across the ground. 0:10:13.160 --> 0:10:15.120 For any of you out there who watch a lot 0:10:15.120 --> 0:10:18.079 of animal videos on Instagram and so forth, you may 0:10:18.080 --> 0:10:23.520 have seen videos of adorable beavers carrying carrots around and 0:10:23.840 --> 0:10:26.240 if you're not looking closely enough, you might think they're 0:10:26.320 --> 0:10:29.240 dragging their tails, But if you will look closely, you 0:10:29.280 --> 0:10:32.360 can see that the tail is off the ground and 0:10:32.400 --> 0:10:33.520 it's helping them balance. 0:10:34.080 --> 0:10:36.320 One of the things I've noticed about watching beavers try 0:10:36.360 --> 0:10:39.480 to move objects around is how much more gracefully they 0:10:39.480 --> 0:10:41.440 do it in the water than on the land. So 0:10:41.480 --> 0:10:44.800 these are semi aquatic mammals, but I don't know, it 0:10:44.800 --> 0:10:47.480 seems to me that the water is where they're really 0:10:47.520 --> 0:10:50.760 in their element. They can swim fast and gracefully, even 0:10:50.840 --> 0:10:55.320 carrying like an unwieldy branch that's kind of unbalanced or something. 0:10:56.000 --> 0:10:57.800 They do that all quite well in the water, and 0:10:57.840 --> 0:11:01.040 then once you see them sort of toddling along across 0:11:01.080 --> 0:11:04.400 the dry land that it looks much more comical and awkward. 0:11:05.160 --> 0:11:06.800 Yeah, and this is going to be important to keep 0:11:06.800 --> 0:11:09.440 in mind when we talk about the amazing ways that 0:11:09.480 --> 0:11:14.400 they transform an environment to better fit their needs and desires. 0:11:15.000 --> 0:11:16.720 Oh but before we get into that, we of course 0:11:16.800 --> 0:11:18.920 have to talk about the teeth of the beaver. This 0:11:19.040 --> 0:11:23.760 is something that is generally an important part of cartoon 0:11:23.800 --> 0:11:27.240 imagery concerning the beaver. A lot of times cartoon beavers 0:11:27.280 --> 0:11:30.120 will speak with a kind of whistle in their voice. 0:11:30.679 --> 0:11:32.360 But we also tend to get it quite wrong. 0:11:32.679 --> 0:11:34.800 Okay, so I'm trying to picture the cartoon beaver. I 0:11:34.880 --> 0:11:38.120 think what we always see is an overbite with two 0:11:38.320 --> 0:11:41.520 kind of square shaped teeth grouped right together in the middle, 0:11:41.600 --> 0:11:46.080 like a person's front two teeth, but large and overlapping 0:11:46.120 --> 0:11:47.880 the bottom lip. Is that about it? 0:11:48.360 --> 0:11:49.440 Yeah? Yeah, pretty much. 0:11:49.960 --> 0:11:51.560 The truth is much more shocking. 0:11:52.920 --> 0:11:58.000 Yeah, yeah, they have these. You know, if you look 0:11:58.000 --> 0:12:01.080 at a skull of a beaver, it's pretty markable because 0:12:01.360 --> 0:12:05.160 it's like this, the really kind of exaggerated rodent skull 0:12:05.960 --> 0:12:09.520 with just incredible incisors, you know, with these these two 0:12:09.520 --> 0:12:12.440 big shovel like teeth coming down from the top, two 0:12:12.480 --> 0:12:15.800 big shovel like teeth coming up from the bottom, and 0:12:15.800 --> 0:12:18.640 then the rest of the the back teeth or much 0:12:18.640 --> 0:12:21.640 further back, you know, giving them some ample room to 0:12:21.720 --> 0:12:24.200 do the kind of woodwork that they need to do 0:12:24.600 --> 0:12:25.559 with those chompers. 0:12:26.200 --> 0:12:29.840 The skull is a powerful bone hinge, and it's like 0:12:30.000 --> 0:12:35.240 it's like a kind of alien biotechnological set of bolt cutters, 0:12:35.280 --> 0:12:37.720 except the bolt cutters are orange teeth. 0:12:38.440 --> 0:12:40.319 That's right, The orange is key. This is something I 0:12:40.400 --> 0:12:43.439 almost never see in like a cute c illustration or 0:12:43.480 --> 0:12:47.800 a cartoon depiction of a beaver. So, yeah, these teeth 0:12:47.840 --> 0:12:51.520 have thick layers of enamel, which has this orange colorization 0:12:51.760 --> 0:12:56.200 because while other rodents boast magnesium enriched tooth enamel, beavers 0:12:56.240 --> 0:12:59.760 have iron enriched enamel. They're like, I mean, it's it's 0:12:59.800 --> 0:13:03.600 like something out of a comic book, right. The iron 0:13:03.600 --> 0:13:07.240 makes their teeth stronger against this the pure mechanical stress 0:13:07.320 --> 0:13:09.560 that they put them through. We should also note that 0:13:09.600 --> 0:13:12.880 these teeth continue to grow throughout their lives, to the 0:13:12.880 --> 0:13:15.000 point where they have to gnaw them down on trees 0:13:15.040 --> 0:13:18.080 to keep them down. But yeah, they're just super resilient, 0:13:18.240 --> 0:13:21.520 always growing, and they're also more resilient to acid as 0:13:21.559 --> 0:13:23.200 well based on their composition. 0:13:23.760 --> 0:13:25.880 Just some tough, rusty looking teeth. 0:13:26.440 --> 0:13:39.400 Yeah, yeah, the orange is really quite shyy okay. Another 0:13:39.600 --> 0:13:43.400 essential biological aspect of the beaver before getting into their behavior, 0:13:43.880 --> 0:13:47.600 is that they have a cloaca. So most mammals do 0:13:47.679 --> 0:13:50.920 not have a cloeca. There are some exceptions, you know, 0:13:50.920 --> 0:13:55.440 you look at the monotremes, golden moles, marsupial moles, ten 0:13:55.480 --> 0:14:00.640 rex just a few examples, but mammals have most lost 0:14:00.760 --> 0:14:04.240 these general purpose openings over the course of their evolution, 0:14:04.640 --> 0:14:07.599 but in beaver's they seem to be present as a 0:14:07.800 --> 0:14:12.360 case of secondary evolution, perhaps as an adaptation I've read against. 0:14:12.640 --> 0:14:14.920 It may have to do with the watery environments they 0:14:14.920 --> 0:14:19.480 find themselves in, protecting themselves against infections that might occur 0:14:19.840 --> 0:14:22.680 due to the state of that water. But it's also 0:14:22.720 --> 0:14:25.280 something and this will become important, I believe in the 0:14:25.280 --> 0:14:27.480 next episode as well. It can make it difficult to 0:14:27.520 --> 0:14:31.040 sex a beaver, as males and females look pretty much 0:14:31.080 --> 0:14:34.080 the same, unless the female happens to be pregnant or 0:14:34.160 --> 0:14:37.360 nursing at the time that you're trying to sex them. 0:14:37.400 --> 0:14:39.440 And when I say you, I of course mean people 0:14:39.480 --> 0:14:42.640 who have authority and expertise to be out in the 0:14:42.680 --> 0:14:45.520 wild trying to sex a beaver. You know, leave it 0:14:45.560 --> 0:14:47.880 to the professional biologists. 0:14:47.440 --> 0:14:50.640 Leave it to beaver scientists. Yes, so these. 0:14:50.560 --> 0:14:55.320 Various features aid the beaver in its primary enterprise of 0:14:55.440 --> 0:15:00.400 ecosystem engineering. We all know that beavers build dams, you know, 0:15:00.440 --> 0:15:03.240 this is, of course is true of the cartoons. But 0:15:03.720 --> 0:15:07.120 what does that really mean? Why? Why are beavers building dams? 0:15:07.120 --> 0:15:11.040 What are they accomplishing, So they actively alter their ecosystem 0:15:11.120 --> 0:15:14.960 via the blockage of rivers and streams with structures of 0:15:15.040 --> 0:15:19.480 like you know, sticks, mud, chunks of trees, that sort 0:15:19.520 --> 0:15:23.440 of thing, all cobbled together to dam up the water, 0:15:23.520 --> 0:15:26.520 and this allows them to create new lakes, new ponds, 0:15:26.560 --> 0:15:31.880 whole floodplains. Meanwhile, the lodges they construct for themselves are 0:15:31.920 --> 0:15:33.880 also made out of this kind of stuff, branches and 0:15:33.960 --> 0:15:36.880 mud and so forth, and they can only be accessed 0:15:36.880 --> 0:15:40.480 from underwater entrances in their constructed ponds. 0:15:41.080 --> 0:15:43.040 Yeah, so this is something I don't know if I 0:15:43.120 --> 0:15:45.640 realized before. I think a lot of people assume that 0:15:46.520 --> 0:15:50.200 beavers live in their dams, but I think the better 0:15:50.240 --> 0:15:54.040 way to think about it is beavers construct dams in 0:15:54.160 --> 0:15:59.440 order to block waterways, which causes the area upstream of 0:15:59.480 --> 0:16:02.880 the dams to deepen and have a more lake like 0:16:03.040 --> 0:16:06.640 environment rather than a flowing river or stream. And then 0:16:06.800 --> 0:16:09.680 in that flooded area that is where they build the 0:16:09.760 --> 0:16:12.520 lodge they live in. So they sort of create a 0:16:12.600 --> 0:16:16.200 flooded area which can it can serve multiple purposes, one 0:16:16.240 --> 0:16:19.440 to house the lodge, but then also they can sort 0:16:19.440 --> 0:16:21.920 of dig out from there. I think you're about to 0:16:21.920 --> 0:16:22.840 mention something about this. 0:16:23.400 --> 0:16:26.440 Yeah, they're a lot like humans. Human beings do this 0:16:26.560 --> 0:16:29.640 with their modern technology. They come to say a dry 0:16:29.760 --> 0:16:33.760 desert environment or a swamp environment, and they're like, you know, 0:16:33.800 --> 0:16:36.400 what would go great here? What I would like for 0:16:36.600 --> 0:16:38.440 my purposes of living here. I'd love it to be 0:16:38.520 --> 0:16:40.800 just like a nice little park with some nice grass, 0:16:40.960 --> 0:16:43.560 you know, and maybe a few trees. I'm going to 0:16:43.680 --> 0:16:47.080 change everything so that it fits my needs. So the 0:16:47.120 --> 0:16:50.680 primary purpose for the beaver dam is to create a 0:16:50.720 --> 0:16:54.760 protective body of water for that lodge, making it even 0:16:54.800 --> 0:16:57.920 more difficult for predators to get at them. And even 0:16:58.000 --> 0:17:00.840 if predators were to get to them, they have that 0:17:00.960 --> 0:17:04.000 underwater escape route in the event of an attack. That's 0:17:04.040 --> 0:17:06.320 the that's the only way in and out now. It's 0:17:06.680 --> 0:17:10.000 worth noting, however, that especially in parts of Eurasia, beavers 0:17:10.040 --> 0:17:12.720 don't always have the same predator threat they once did. 0:17:13.119 --> 0:17:15.359 But they build anyway because no one told them not to. 0:17:15.880 --> 0:17:18.960 And also, more seriously, like, even though they are not 0:17:19.040 --> 0:17:21.440 predators now, I mean that's you know, any kind of 0:17:21.480 --> 0:17:25.919 evolutionary change would occur over a much vaster period of 0:17:25.920 --> 0:17:29.840 time than the removal of their predators. 0:17:29.359 --> 0:17:32.359 Amounts to right, So an environment full of say like 0:17:32.440 --> 0:17:35.000 gray wolves and bears may have shaped them. And even 0:17:35.000 --> 0:17:37.480 if there are many fewer of these predators than there 0:17:37.520 --> 0:17:40.080 once was, that they are still the animal made by 0:17:40.080 --> 0:17:40.680 that world. 0:17:41.200 --> 0:17:44.320 Right. For instance, they're still certainly nocturnal creatures. I mean 0:17:44.320 --> 0:17:47.320 they're also active, you know, dusk and dawn a little bit, 0:17:47.359 --> 0:17:51.600 but during the day proper, they're inside, they're resting, and 0:17:51.720 --> 0:17:54.680 part of that is to avoid predators. Now you mentioned earlier, 0:17:54.760 --> 0:17:57.000 Joe that you even just looking at videos, you can 0:17:57.040 --> 0:18:00.000 tell that they're more awkward on land than they are 0:18:00.080 --> 0:18:04.040 in the water. And that's of course another big important 0:18:04.200 --> 0:18:08.040 aspect of their damming of waterways, creating this sort of 0:18:08.119 --> 0:18:12.359 vast flood plain, like turning a stream going through a 0:18:12.440 --> 0:18:16.280 forest or something to this effect into kind of a 0:18:16.320 --> 0:18:21.240 flooded forest environment. This opens up speedy water routes back 0:18:21.280 --> 0:18:23.920 to their lodge. From perspective, feeding grounds. 0:18:24.119 --> 0:18:26.199 Yes, sort of the same way. You can imagine it 0:18:26.280 --> 0:18:30.879 like humans creating roads, like paved roads between say the 0:18:30.960 --> 0:18:33.520 farms that they work during the day and the houses 0:18:33.560 --> 0:18:36.399 they live in. But beavers would do this by instead 0:18:36.440 --> 0:18:39.240 creating flooded areas. Especially they can sort of like dig 0:18:39.280 --> 0:18:42.240 out channels along the bottom that the water from these 0:18:42.240 --> 0:18:45.879 flooded areas can run into, allowing them to have a 0:18:45.960 --> 0:18:48.840 sort of canals like roads made of water where they 0:18:48.840 --> 0:18:51.480 can move quickly, where they can move submerged, which is 0:18:52.119 --> 0:18:54.760 safer and better for them than trying to move awkwardly 0:18:54.800 --> 0:18:55.439 over land. 0:18:56.119 --> 0:18:58.879 Yeah. Now, in doing this, of course, they alter the 0:18:58.920 --> 0:19:02.920 ecosystem local ecosystem in a major way, opens up opportunities 0:19:02.920 --> 0:19:06.480 for various other organisms as well, and also discuss some 0:19:06.560 --> 0:19:10.359 of the potential downsides at least for some organisms in 0:19:10.359 --> 0:19:12.600 a bit. But at any rate, this cements the beaver's 0:19:12.640 --> 0:19:18.240 place as a keystone species. Beaver's just just completely change 0:19:18.320 --> 0:19:22.359 the immediate environment, produces more open water, higher water tables. 0:19:23.000 --> 0:19:25.800 And yeah, it's this entire system they have going for 0:19:25.840 --> 0:19:28.440 them here. It's just so fascinating. You can if you 0:19:28.480 --> 0:19:32.280 look online, you can find some some side profiles, some 0:19:32.400 --> 0:19:36.200 cutaways of what the lodge looks like, and it's pretty ingenious. 0:19:36.520 --> 0:19:38.200 It also serves as a place for them to store 0:19:38.280 --> 0:19:42.200 food and even provides refuge during frozen months. They don't 0:19:42.320 --> 0:19:45.800 hibernate properly, but they can hold up in there. 0:19:46.320 --> 0:19:48.200 One of the things I've read about is that they 0:19:49.280 --> 0:19:53.000 often can store lots of food, so they're vegetarians that 0:19:53.119 --> 0:19:56.960 eat actually like you know, parts of trees, vegetation from 0:19:56.960 --> 0:19:59.800 all around them, which they can keep stored in the 0:19:59.840 --> 0:20:05.080 world water underneath the pond created by their dams, and 0:20:05.119 --> 0:20:08.000 that's an interesting thing. They can raise the water level 0:20:08.119 --> 0:20:13.000 in order to help protect areas of food storage in 0:20:13.119 --> 0:20:16.240 the water for the winter, because by raising the water level, 0:20:16.320 --> 0:20:19.360 they create more area underneath that won't freeze over when 0:20:19.400 --> 0:20:20.320 the weather gets cold. 0:20:20.720 --> 0:20:25.160 Yeah, and these lodges and dams that they can even 0:20:25.160 --> 0:20:28.960 though the beavers themselves tend to only live about I 0:20:28.960 --> 0:20:32.560 think eight years max, a single lodge and dam can 0:20:32.600 --> 0:20:35.919 be maintained over generations, so the lodges may end up 0:20:35.960 --> 0:20:39.120 with like several stories to them, and the dams can 0:20:39.119 --> 0:20:42.560 get quite massive. There's an Alberta area dam that was 0:20:42.560 --> 0:20:47.280 built apparently in the nineteen seventies. Initially wasn't discovered till 0:20:47.280 --> 0:20:49.199 around two thousand and seven because it's just out in 0:20:49.200 --> 0:20:51.320 the middle of nowhere. It's not like in downtown Alberta. 0:20:51.400 --> 0:20:54.600 It's like out in the boonies and it's thought to 0:20:54.600 --> 0:20:57.879 be the world's largest beaver dam known beaver Dam anyway, 0:20:57.960 --> 0:21:01.440 covering a good half mile. There's actually an Alice Obscure 0:21:01.520 --> 0:21:03.919 article about it. If anyone's interested. Just look up world's 0:21:03.960 --> 0:21:06.920 largest beaver dam and you can see some like aerial photographs. 0:21:07.600 --> 0:21:09.439 You know, something interesting I was reading about was the 0:21:09.520 --> 0:21:14.919 role of beavers in maintaining ecosystem health by allowing for 0:21:15.000 --> 0:21:18.760 a greater diversity of different types of plant life to thrive. 0:21:18.840 --> 0:21:21.200 I think sort of in the same way that forest 0:21:21.280 --> 0:21:23.879 fires you might think of them as purely destructive. Of 0:21:23.920 --> 0:21:27.200 course they are destructive, but you know, forest fires occur 0:21:27.800 --> 0:21:31.560 naturally all the time, and when a forest burns, that 0:21:31.600 --> 0:21:35.520 creates sort of new opportunities for new types of plants 0:21:35.520 --> 0:21:38.040 and other life forms to thrive in a place that 0:21:38.160 --> 0:21:40.080 was once covered up by you know, a lot of 0:21:40.119 --> 0:21:43.679 tree canopy. So in the areas around beaver dams and lodges, 0:21:43.760 --> 0:21:46.120 they will clear out lots of the trees. They literally 0:21:46.240 --> 0:21:48.280 chew them down and they'll fall, and you know, the 0:21:48.320 --> 0:21:51.120 beavers will do what they will with them. But this 0:21:51.160 --> 0:21:54.520 creates all kinds of opportunities for other plants and other 0:21:54.800 --> 0:21:57.840 life forms that wouldn't normally thrive in the forest to 0:21:58.800 --> 0:21:59.680 have a shot. 0:22:00.119 --> 0:22:04.800 Yeah. Yeah, the paper that I came across was talking 0:22:04.840 --> 0:22:07.000 about sort of like the pros and cons. I have 0:22:07.040 --> 0:22:09.400 another one I'll get into about some of the potential benefits, 0:22:09.400 --> 0:22:13.280 but just to give you a full idea of sort 0:22:13.280 --> 0:22:17.040 of the rodent altered landscape we're talking about here, I 0:22:17.080 --> 0:22:20.200 was looking at a twenty fifteen paper published in IOP 0:22:20.400 --> 0:22:24.240 conference series, or presented in the IOP conference series Earth 0:22:24.240 --> 0:22:28.800