Consider the Packrat

into the deserts of Arizona. And while I was there, my wife and I visited the Desert Museum, which I highly recommend anyone visiting Arizona there they go check that out because it's it's not really a museum, it's more of a botanical garden with some animals living in it, and uh, it really opens your eyes to how diverse a desert ecosystem actually is, how much life is there, even if it is life that is thriving on a

on a smaller level. You know, so many amazing varieties of CACTI got to see alive have Alina for the first time, which was which was on my list of things to do. But then I also learned for the first time that a pack rat is an act will than well. I I just kind of assume prior to this that when people said, oh, he's a pack right, he's a pack rat, that maybe we were referring to some vague, um myth or legend that rats like to collect items and store them somewhere. I had no idea.

I have to admit that it was an actual creature. Yeah, yeah, actually, um, I'm sure that a lot of our listeners know this. Listeners in the Southwest, right, because apparently pack rats um are a bit of a pestilence, a bit of a problem and um or something that people try to get rid of because they like to take up residents in cars sometimes and and choot through the wiring or just get into the house. Yeah, they like to set up camp and as well discussing this this episode, they do

collect objects. They like to use them to decorate their little homes and sometimes the often the objects they collect in an urban environment are not things you want them running off with, like parts to your vehicle, important parts or car keys or teeth. These kind of things can convantage We have pack rats in the area. They can be very destructive, but they are a very fascinating species,

like deceptively fascinating and deceptively useful. So we decided we would we take the time to to consider the pack rat and to examine some of the things that make this an interesting species, which you know, the next time you look out at a desert vista, you should consider these guys and how elaborate they make their homes. But before we talk about this, let's talk about where they actually roam in a bit about what they look like. Yeah, there are presently twenty one living species of pack rat

um or neatoma, occurring a wide rangement of habitats. You'll find them around the edge of the Arctic Circle, all the way the tropics of Nicaragua, throughout western Canada, most of the US Mexico, Central America, also known as trade rats or wood rats. Wherever they roam, though, they have two key requirements, right they need succulent plants for food and adequate shelter. And when I mean succulents, that of course mean cacti and tiny cacti and desert not delicious

succulent not not just delicious foods. That they are cactus laughters. They depend on the cactus. That's where they get most, if not all, of their water. Like these guys are in their natural environment, They're not going to go search for a stream to lap up water. They're getting it exclusively from the cacti that they're chewing on. And I dare say that these guys are actually pretty cute and cuddly looking. Yeah, they look like little mice, like they're not.

I mean, I don't know what one expect they. I guess you'd expected to have little pockets and and like chains and jewelry and kind of look like Hoggle and Labyrinth or something. But I have like a little grocery cart. Yeah, yeah, a little grocery cart full of junk pushing along. But no, they kind of to the untrained eye, they look just like a mouse of some sort. Yeah. They have grayish

brown fur with tawny undertones, white feet and undersides. They can be distinguished from their distant relative in no way rat by their blunt noses and long whiskers, and they usually measure anywhere from about eight inches long to fifteen

inches long, depending on the species or the subspecies. Um. The tail is another five to seven inches, and wood rats tails are more furred than scaly, and they have so they don't have that that that possum rat tail where it's just like a naked, squirmy worm type thing. The most of the time you see that and you kind of recoil from it, but this is more of a furry tail and they have extraordinary large round ears. Again, this is what makes them, I guess, uh, we can

put them in the cute category because of this. The tail is covered by loose skin which can be shed to escape or predator. That's that was really fascinating because it's it's kind of like a lizard, right, except it's not shedding the entire tail. It's just shedding the skin off of it, which sounds horrifying as well, but certainly of an owl is coming after you better that he

takes the skin off your tail than all of you. Yeah, it's a nat trick, right, and the and the owl get something out of it as well, right, Thanks for the memories. Um so. Yeah. And they are usually solitary, although a bit we'll talk a little bit about more how they deviate from solitary confinement of their of themselves.

What is interesting to the solitary because the idea of a pack rat is is we throw the term around in human environments is you often think of a person who lives alone and collects lots and lots of things. You're thinking hoarding territory, hoarding territory, which is a whole another podcast which we'll get to, but but much darker podcast than than what we're talking about here. Yeah, because these pack rats, um, they're not just trying to accumulate

for accumulation's sake. There seems to be a couple of different things going on for the for the reasons why they are accumulating debris. But let's first talk about these

guys as architects. So the big thing about the pack rat and the thing that fascinates us and and and ultimately the reason we're talking about them now is that they build little dens, little homes, And if you look at one of these houses, it kind of looks like a little dollhouse made out of sticks and garbage and just desert materials just cobbled together into this little home.

It's it's it's really fascinating. And it's not just one of these things where we look at it and we're like, oh, it looks like a little home with little rooms for different uses. They actually use the different rooms for different things. It's very intentional. Beginning with what you could call the front door. Uh, usually they will use stands of troll or prickly pear cacti Yeah, the whole thing is is surrounded with prickly cactus bits that serve as a barrier.

And this is really interesting because, um, you have Native American tribes in the area that would depend on these living fences where they would take bits of cactus and sort of strap them together and make little fences out of the cacti. And the pack rat does the same thing and was doing the same thing long before humans occupied the area, right, So if a predator were to come to their nest, then it would be met by this,

you know, cacti, which would not feel so great. And the pack rats actually cut them into three to four inch long pieces and carry them to their nest sites in their mouth. So if you see a stand of saprickly pair and you see little score marks on it, you can tell that a pack rat has been there. Um. So the cacti does serve both as a nest protector and as food and also provides some really good installation. The temperature inside of that that pack rat den is

really stable and and it all comes from the installation. Okay, So the nest actually consists of two parts. There's the house, which is the collective material, which is mostly above ground, and then the nest itself, which is usually dug part way below grounds. So that's where we start to see these different chambers and these specialized areas for the pack

rat to live in. Right, they'll have several rooms that are devoted to food storing food because ultimately, if you're a rodent and you're living it rough out there in the world, you're gonna want to store away some food, right to survive the lean tie. And they'll have as much as three bushels of plant material stored away in there.

And then they have another area that is actually thought of as um We call it sometimes a daytime retreat, like a day room, which is very helpful during the more intensely heated summer months, right, But it's also used as a nursery sometimes, so it's like a bedroom slash nursery slash rump. This room, I guess, yeah, sort of like your guest room in your house perhaps is a multipurpose room. And then this is really interesting too. They

have a latrine. And and now that sounds kind of like if you're like, oh man, why would you have you know, the latrine as part of your nest. But well that humans have a ladder into talk. Since we started doing indoor plumbing and moved our bathrooms inside, everyone has a room that is devoted almost entirely to pooping. So you may you may not think of it that way, but that's what you have. What do you think it would do to us psychologically if we just renamed restroom

poop room everywhere wholesale? Yeah, like no matter where you went, and you just say I've got good of the pooper room, Yeah, it would. I mean the thing that gets me, it's one thing to call the bathroom. Okay, so bathroom all right, called a bathroom because it has a bathroom there. All right, fair enough, You're gonna put the spotlight on the thing that's most relaxing and has less to do with our

bodily functions, the restroom. Okay, Well you're going in there, you're well, you may be doing something RESTful, but it also there also might be a very stressful incidents going on inside that room. But what gets me is the water closet where it's where this is when you have have a room that only has a toilet in it, Like if anything is a pooper room, that's a pooper room. But we call it the water close. It's it's a magical little room that has a fountain and a waterfall

in it. It does some kind of love the I'm going to the multa closet, you see, but that is essentially what the pack rad has, a water closet because again the pack rick doesn't want to go outside during this horrible heat and uh and use the restroom elsewhere. She needs an indoor potty and that's what this room is. Well, if she went outside too, she would be subject to the predation from like we said, owls, snakes, and coyotes. So this is another reason to have an indoor latrine um.

And actually too, when they bring in some of their collectibles, they do bring it into the lutrine and the urinate on that, which creates a bit of a specimen that we'll talk about later on. That's very helpful to our understanding of the environment. I've I've heard it put that they'll bring in things to quote unquote decorate their house, and then as they tire of these decorations as they become old, or as we'll discuss a minute, when some of the elements that they used to decorate when they

lose their functionality. They dumped them into the latrine room, so not everything goes directly to the traine room. Sometimes it's like I'm kind of sick of that painting. I'm gonna put it in the poop chamber. Well, and see again, this is very intentional, right, It's interesting that they would be decorating in quotes right their dens and having a sort of revolving artwork or installation that eventually gets put into what we call the midden. This is the area

that they urinate on. And we'll talk more about the midden in a moment, but they also have been known to line their homes with leaves, yes, particularly bay leaves, you know, the type of leaf that you put in your spaghetti. Very aromatic, and you would think of this as a kind of wood rat potpourri or pack rat potpourri. You might think that at first, but it actually serves a far more important purpose, and that is to keep

the pest down. It's basically they're fumigating the den, right, so they don't want ectoparasites hanging around, particularly where they sleep, so they line this area with those bay leaves, and that really acts as a repellent, which I thought was completely fascinating. So not only do you have artwork that is revolving, artwork that you know, disappears and goes into littering when they get tired of it, but you've got

these nice fragrant bay leaves scenting the den. Yeah. I also found it interesting that sometimes they have roommates, like non rodent roommates such as box turtles, skinks, lizards, well know, sometimes other rodents, but which you also see with the with beavers as that recall, um, the other animal that is generally the beloved animal that that builds houses out

of craft that it finds. Yeah, well, because the beaver is like, oh, then the beaver is we look at the beaver, is this uh, this industrious creature that's doing good in the world. But the pack rat is a past The pack rat is a destroyer, right, but they're basically doing their own thing that it's just to what extent they interfere with human plans. Well that's because beavers don't try to how wire your car. Yeah well yeah

yet yet. Um so I found it interesting that the pack rats may have some other creatures living around, Like I mean, a pack rat that lives with the box turtle. That that's the reality show right there. That are a sitcom set up that I would watch. Yeah, um, and we have you know, said that they're primarily solitary, but the fact of the matter is is that they are largely natural inning all these societies, and they live in a pretty loosely cooperative society. So when the pups are weaned,

this is really interesting. Males babies, by the way, one to four babies, the males will actually leave the den and they will go off into the hinter lands, but the females will move to adjacent stick houses, remaining close to their mother. And then when the matriarch dies, one of her daughters actually will inherit the stick home and a single wood rat can um maintain this home for several generations, for the same family for decades and decades.

Oh wow, Now this this leads to an idea in my mind, what if you had Downton Abbey all pack rats already would be great? Like's Maggie h Maggie Smith? Is that her name? The dowurs on there right right? Yeah? As a pack rat, I think that would be great. Well, they would have an awesome art collection already, you know, that um again, another great idea for a show there. But you know what, this is all sort of pointing to this idea that pack rats aren't just collecting things.

They are actually giving us a clue of how um, how the earth once was. And we can look at them not just as architects, but as archaeologists. And we're gonna take a quick break, but when we get back, we're going to discuss this idea a bit more. All Right, we're back, and we are already inside the pack rats again.

We've talked about their latrine room, the midden, where they urinate coviously on old bits of art and uh and uh and by which I mean bits of plant pollen, animal bones in more recent years, lots of human artifacts, pieces of cars. There's one story about the man's false teeth going missing, and they showed up in one of these dens, anything that catches their fancy, and they were gathering the stuff from a wide territory. Yeah, but a hundred mile radius is where they gather all of these

different materials. And so when a pack rat urinates on its collections, the high calcium oxalate content of the urine helps to solidify and preserve the items in a hard, resinous or vitreous looking like material called midden. Yeah, their urine is very viscous too, just to throw that im engine in your mind. Yeah, and the midden kind of looks like peanut brittle. It's been described as at or

chocolate bar filled with nuts. And there's even one account of um people who were seeking out the gold rush back in the eighteen hundreds, UM getting to a part of the landscape that they were traveling through UM and not having enough to eat and actually finding the midden and using nuts as a Yeah, they said it looked like, well, kind of like twistlers. I guess which I'm eating today because it's Halloweens were recording it. Yes, I guess you

could say like a honey. Yeah, looking if I look on the package, Um, well no, I guess there're no ingredients on this. This is a fun size. But um, yeah, it wouldn't be surprised if the midden midden materials like ten percent. But but yeah, you've given a long enough time though, this stuff will actually will crystallize into something.

It's almost like amber. And consider too that pack rats have been doing this for at least forty tho years we found midden material that's forty thou years old, So inadvertently in their garbage, they have preserved some fascinating pidbits about the history of the planet. Much like with archaeologist when you look at human settlements, if you can find where they're throwing away their garbage, gold mine, because that

gives you this insight into their daily life. What were they eating, what were they using, what was their life consisting of outside of uh, you know, religious iconography and what have you. What was the what was their daily life consisting of? With the with the pack rat, although it's more of a more of an insight into past climates,

especially in dry western North America. Yeah, and actually, previous to the nineteen sixties, when midden was discovered and it was discovered that you could actually strike archaeological gold here and use this to to look into the past, they weren't quite sure what some of the atmospheres or environments

were during different eras. So in the nineteen sixties it was discovered that these deposits left in caves and crevices by pack rats contained these assemblages of fossil plants, and that's when they began to say, okay, um, we can look at this and we can figure out what's happening

during these tens and tens of thousands of years UM. So, for instance, since numerous vegetation zones occur over relatively short distances in places like the Grand Canyon, the newly discovered pac rat middens became a really good tool for comparing the Pleistocene vegetation zones with modern ones. And they did this by using radiocarbon dating. Yeah, so they could look through all those layers and try to figure out what

was going on when. And then in addition to that, the urine actually acted as a bactor aside, so the organic material was preserved really well. Now, when future generations look back, I can't help but think they'll be a gap though, the period during which cowboys ate all of the candied urine cakes that the that the pack rats left for them in their in their debts, a gap

in the midden fossil record. Yeah. All you have to do is look through there, I'm sure evidence in the caves and their droppings to try to find out what was going on. Now, one a little bit about the pack rat that we neglected to mention earlier is that, Okay, you have an animal here that lives almost exclusively on cacti. It's just eating loads and loads of cactus and its skintting most of its water from the cactus. But there's

several different toxic plants thrown in here as well. I mean you have the juniper, the stage brush, the UK. There's a lot of toxin in there, so that the animal has to be able to withstand a certain amount of toxin, but also interestingly enough sort of manage its diet depending on what the toxin levels are. Yeah, and this is interesting. Some species or subspecies have actually evolved their their kidneys to be able to excrete some of

the toxins out really well. But what we're talking about specifically here are food rats in the deserts of the US and the Southwest, where again there's very few food resources and you can't really be picky about what's available. So they have found, they were found, but they have developed, i should say, methods of dealing with this rather toxic appetite. They'll sample a number of different toxic items so they're not just chowneling down on one thing and potentially getting

an overload of one particular toxin. They're eating smaller meals, which is kind of you know, as humans, we can understand that if the food is horrible, you eat less of it. They'll increase the time between meals, which makes sense too, because there's something toxic in there, you want to let your body work through it a little bit

before you hit it again. And then if water is available again they get most of their water through cacti, but if there is a water source available, then they will drink more water to help compensate for the toxins, to try to flush it out. Yeah, it's kind of like some like college kids, I guess on a on a weekend, you know, drink more water, watch what you eat,

and and make sure you recharge between toxic excess. Now, biology Professor Denise Deering actually compared wood rats or pack rats that eat only a single plant, and these are called specialists, these these wood rats, and so they would eat something like juniper and that wasn't a big deal for them because again that their kidneys in their livers had evolved enzymes that could break this down. But what

you're talking about are those generalists, those wood rats. And that's where she discovered that they had these different behavioral responses in place to try to manage the amount of toxins in their bloodstream, which so it's actually pretty clever because you think about it, they get the sustenance, but they don't keel over with a belly full of poison. Um. They get to manage that process. And so she said that there's a possibility that they have a sort of

poison detection system in place. So the generalists are they're they're more smart in their management of toxic diet, whereas the the specialists are just hardy. They're kind of like the Shane mcgallan's of the rodent world, where they could they just have a higher tolerance. Well, they just keep hitting that one plan over and over again. So it makes sense that they would evolve to be able to

deal with it. Um. But Deering actually says that other researchers have found receptors in the guts of other rodents, and she thinks that rodents um, particularly the wood rats, may be able to detect bitter taste in their gut receptors. Yeah, so should they eat it and then their figures out what's going on, and then then they get the signal we need to drink some water, We need to space things out exactly, or let's just not eat a whole bunch of this. Let's not gorge on this because you

know this is toxic. So that's pretty fascinating getting a similar thing in my own stomach from the twistle and the twist at this point. Yeah, alright, So there there, that's the pack rat for you. Again. I'm sure a number of you, you guys and gals out there live in areas with the pack rat rooms. You may have some crazy pack rat stories that have either been handed down to you or that you've you've encounted yourself. We would love to hear about those, so be sure to

write in with with those tales. And again, if you head out to Arizona spending any time between Phoenix and Tucson, go check out the Desert Museum. It's really fascinating. You'll learn a lot of stuff, uh, and you get a lot of walking and hiking done as well, and you get to see you have Alina, which which is a treat which is not a pig really more kin to a guinea any pig type of creature. But but it looks kind of I guess did you ride one. I

did not write one. They're they're vicious. They will they'll tusk you man. But yeah, so go check that out. Anyone out there listening to us, if you would like to share any of your tales with us about the pack Rat, or if you want to talk about any other episodes we've done in the past, you can find us on Facebook and tumbler. We are stuff to blow your mind on both of those, and we also tweet.

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