November 13, 2012 • 23 mins
It's true: the word "packrat" is more than slang for hoarders and collectors. Join Robert and Julie as they discuss the pint-size rodent's love of decoration and den-building. Plus how do their toilets aid cowboys and archeologists? Tune in to find out.
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Speaker 1 (00:03):
Welcome to Stuff to Blow your Mind from how Stuff
Works dot com. Hey you welcome to Stuff to Blow
your Mind. My name is Robert Lamb and I'm Julie Douglas. Julie.
I just recently returned from a trip out west, out
into the deserts of Arizona. And while I was there,
(00:24):
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
(00:45):
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
(01:07):
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
(01:29):
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
(01:49):
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
(02:13):
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,
(02:36):
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
(02:58):
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
(03:20):
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
(03:41):
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
(04:03):
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.
(04:23):
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
(04:46):
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,
(05:07):
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
(05:29):
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
(05:50):
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.
(06:13):
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
(06:33):
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
(06:56):
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.
(07:16):
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,
(07:37):
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,
(07:58):
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
(08:21):
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
(08:43):
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
(09:03):
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
(09:26):
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.
(09:46):
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,
(10:09):
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
(10:31):
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
(10:51):
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
(11:14):
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
(11:36):
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
(11:57):
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
(12:19):
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
(12:41):
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
(13:03):
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
(13:23):
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
(13:45):
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.
(14:09):
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,
(14:34):
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,
(14:56):
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
(15:18):
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
(15:40):
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
(16:03):
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
(16:26):
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
(16:48):
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
(17:10):
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
(17:34):
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
(17:55):
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
(18:16):
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
(18:36):
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
(18:58):
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
(19:20):
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.
(19:44):
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
(20:05):
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,
(20:27):
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
(20:50):
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.
(21:10):
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
(21:32):
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,
(21:58):
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,
(22:22):
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,
(22:46):
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
(23:06):
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
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(23:27):
You can find our Twitter account by our handle blow
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on this and thousands of other topics. Is it how
Stuff Works dot com
Welcome to Stuff to Blow your Mind from how Stuff
Works dot com. Hey you welcome to Stuff to Blow
your Mind. My name is Robert Lamb and I'm Julie Douglas. Julie.
I just recently returned from a trip out west, out
into the deserts of Arizona. And while I was there,
(00:24):
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
(00:45):
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
(01:07):
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
(01:29):
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
(01:49):
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
(02:13):
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,
(02:36):
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
(02:58):
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
(03:20):
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
(03:41):
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
(04:03):
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.
(04:23):
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
(04:46):
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,
(05:07):
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
(05:29):
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
(05:50):
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.
(06:13):
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
(06:33):
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
(06:56):
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.
(07:16):
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,
(07:37):
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,
(07:58):
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
(08:21):
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
(08:43):
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
(09:03):
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
(09:26):
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.
(09:46):
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,
(10:09):
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
(10:31):
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
(10:51):
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
(11:14):
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
(11:36):
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
(11:57):
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
(12:19):
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
(12:41):
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
(13:03):
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
(13:23):
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
(13:45):
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.
(14:09):
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,
(14:34):
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,
(14:56):
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
(15:18):
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
(15:40):
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
(16:03):
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
(16:26):
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
(16:48):
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
(17:10):
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
(17:34):
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
(17:55):
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
(18:16):
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
(18:36):
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
(18:58):
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
(19:20):
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.
(19:44):
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
(20:05):
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,
(20:27):
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
(20:50):
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.
(21:10):
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
(21:32):
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,
(21:58):
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,
(22:22):
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,
(22:46):
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
(23:06):
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
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your mind on both of those, and we also tweet.
(23:27):
You can find our Twitter account by our handle blow
the Mind, and you can also drop us a line
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