March 22, 2025 • 49 mins
We are creatures of the epigean world: the world of light on Earth’s surface. But there is another world – a world beneath the surface. In this classic episode of Stuff to Blow Your Mind, Robert and Joe venture into the world of cave biology or biospeleology. (part 4 of 4, originally published 3/14/2024)
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Speaker 1 (00:06):
Hey, welcome to Stuff to Blow Your Mind. My name
is Robert Lamb. Today is Saturday, so we have a
vault episode for you. This is going to be part
four of our series, Part four of four titled Life
in the Hypogenean World. We're gonna wrap this one up today,
so let's dive right in. This originally published three fourteen,
twenty twenty four.
Speaker 2 (00:30):
Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.
Speaker 1 (00:40):
Hey, welcome to Stuff to Blow your Mind. My name
is Robert.
Speaker 3 (00:42):
Lamb, and I am Joe McCormick, and we're back with
the fourth and final part of our series on cave
biology and cave environments. If you haven't listened to the
other parts already, this will probably be a richer experience
if you go back and check those out first. In
the previous parts, we talked about some of the common
characteristics of cave environments, especially as they pertain to the
(01:05):
life forms that might inhabit caves. We talked about the
different types of organisms you find in caves, the ones
that are fully cave adapted versus the ones that are
only visitors. We talked about cave adapted organisms such as
the blind Mexican cavefish, also known as the Mexican tetra
the ome, which is a type of cave salamander found
(01:27):
in the Dynaric Alps. We talked about bat guano, We
talked about snakes that hide in caves and attack bats
as they come and go. We got into a lot
of great stuff, and today we're here to round out
the series.
Speaker 1 (01:41):
Yeah, with a lot of like a lot of our
multi part episodes, it's kind of like the first episode
is kind of like a lot of the initial information
you need, and then the second episode this is where
you find some of the core stuff that attracted us
to the topic to begin with. Part three we kind
of like fill in with a little more data some
other interest entries in said series in the fourth episode
(02:03):
or whatever the final episode happens to be. Generally, that's
where it's like, what's left. What's the thing that came
up in our research that we didn't know we were
going to be excited about, or or in some cases,
maybe what's the weird tangential connection that also came up
or we found ourselves drifting into in the in our journey. Oh,
I think that's a good way to characterize it. So
(02:25):
what have you got, rob Well? I mentioned this earlier.
I forget which of the earlier episodes, but I mentioned
the extinct cave bear in Passing, and I would just
kind of kept touching back in on the subject as
we were working on the other episodes, and finally I
was like, Yeah, we need to go in a little
deeper and talk about what is ultimately like a really
fascinating organism. There have been disagreements and mysteries regarding it,
(02:49):
and it is an organism that, while no longer with us,
does overlap with our ancestors. You know, it was an
ice age creature. Include did here for you, Joe a
reconstruction and image of what one of these bears would
have looked like potentially, And in a bit I'll get
into like what are some of the main anatomical features?
(03:11):
But just looking at you can tell this is a
very huge bear. If it doesn't look that different from say,
like a large you know, grizzly bear, brown bear of
some sort. Coloration is brownish, but one might notice that
the head is enormous. It has a much bigger head
than one might expect, certainly on an extant bear.
Speaker 3 (03:33):
Yeah, it looks a lot like a grizzly. Though I'm
no bear expert, it does appear to me in this
reconstruction to have a somewhat shorter snout and the and
the sort of boxier.
Speaker 1 (03:44):
Head boxier and I'm to understand would have been what
would have appeared wider as well. So we're talking about
Ursus spilaeus. It's a member of the Ursus genus, alongside
the brown bear, which includes grizzly subspecies, among others, the
polar bear, the American black bear, and the Asian black bear.
(04:07):
That means it's naturally a member of the larger Ursudae family,
which also includes the likes of giant pandas, short face
bears and others.
Speaker 3 (04:16):
Oh, I didn't realize pandas were technically in that family.
Speaker 1 (04:20):
Yeah, yeah, Like one of the interesting things about pandas
is that pandas are herbivores for the most part, but
they still have a carnivores digestive system, and they still
have like carnivore jeans, So they're pretty fascinating in their
own right. You know, it's easy to overlook how interesting
pandas are, especially if you go to a zoo and
(04:42):
you see one in captivity that is probably not doing
much other than sleeping or eating pamboo.
Speaker 3 (04:48):
The last time I went to a zoo, the thing
I saw that filled me with the most joy was
actually vicarious joy through a panda when I saw the
feeders through some new bamboo into the enclosure, and the
panda went up to the pile of bamboo and literally
just flopped in. It, just flopped down in its food, like, ah,
give it to me.
Speaker 1 (05:07):
It is literally their favorite thing, Yeah, rolling around in it.
More on this connection to the panda in a minute here,
but yeah, the cave bear when extinct. I do want
to highlight that the exact timing for this depends on
exactly what sources and what evidence you're looking at. I've
seen between twenty eight and twenty seven thousand years ago
(05:28):
during the last glacial maximum. I've seen twenty four thousand
years ago, and in some sources, some of the older sources,
you also see fifteen thousand years ago cited as an
extinction point. But I believe an earlier point in twenty eight,
twenty seven, maybe twenty four is generally favored by scientists today.
That's generally the range. The broader range in which I'm
(05:49):
tending to see the numbers and the sources I was
looking at. And the interesting thing about the cave bear, too,
is that this animal is a recent enough denizen of
the planet that we have been able to study its
soft tissue in addition to its bones, and it's actual
you know, we're able to study like the chemical composition
of its bones. There was even a frozen specimen discovered
in twenty twenty, I believe, and we've been able to
(06:10):
sequence its genome, so we're able to learn a fair
amount about what they were and what they did, though
certain mysteries remain about, you know, their exact lifestyles, their
interactions with other organisms and so forth. Well, let's come
back to the cave theme, right, because that's the umbrella
in which we're just under which we're discussing the cave bear. Here,
(06:32):
we're of course, not talking about an obligate cave dweller.
This is not a blind, hairless bear living in the depths,
as I'm suddenly realizing. As interesting as that might be,
I'm assuming some fantasy weaver has done something like that before.
But now this would have had at best been a
troglophilic creature.
Speaker 3 (06:52):
Okay, so the troglophilic creature enjoys visiting caves. It may
visit caves for a number of reasons, but it doesn't
live there permanently, and it's not biologically adapted to full
time life in the caves.
Speaker 1 (07:05):
Yeah, Like it's not just hanging out in there all
the time, eating bats or anything. But you know, the
cave moniker can be confusing with a lot of these
species because of course we speak of cave men either
in terms of prehistoric Homo sapiens or Neanderthals. Though even
with the latter, who certainly did utilize cave environments as
did humans, they used open air sites for various activities
(07:26):
as well, it seems, so it's not like they just
lived in caves or or and they're certainly not creatures
that were obligate cave dwellers. Plus, the cave moniker sometimes
has as much to do, if not more, to do
with the places where we've discovered the remains, because, as
we've touched on before, I think in this series and
probably in general, like caves are a great place for
(07:49):
remains to be preserved. To some degree, I saw a
paper that was quoting an expert on cave bears. It
was like the bears slept in caves and they had
the good fortune to die in them, something to that effect.
You know, they're like, fortunately for us, they died in
caves a lot, and so we have a lot of
remains to look at. But anyway, just because we have
(08:10):
come to refer to a creature as a cave animal,
it doesn't necessarily mean that it lived in caves. The
main example of this era would be the cave lion
or Panthera spileea, also known as the step lion, which
is now understood to have largely lived in open areas
and possibly woodlands. But we know them a lot of
(08:31):
We know a lot about them from skeletal remains found
in caves, thus cave lions.
Speaker 3 (08:37):
But it's not thought that that's where they spent a
huge amount of their time. It's more just like we
happen to have gotten some remains from caves.
Speaker 1 (08:45):
That's right, yeah, I mean there are remains found in
caves are apparently best understood as on one hand, perhaps
the accumulations or middens of extinct cave hyenas. These this
was all This is also known as the Ice Age
spotted hyena that would have scavenged carcasses and brought them
back to the caves where they lived, or at least
(09:07):
the cave openings where they lived. These would have been
This is an example of something that did live in
caves based on our current understanding, and so they would
have hoarded, scavenged, and killed prey in such places, while
also competing apparently with Neanderthals for some of the same
cave environments. Oh interesting, But back to the cave lion.
It is also thought that they might have ventured into
(09:28):
caves during the winter, especially in search of hibernating bears
that might in some cases be easier to pick off,
especially if they were desperate for the food. And they
also may have periodically entered caves in order to steal
food away from cave hyenas, though to be sure, it
seems like they largely preyed on larger wild herbivores like
(09:49):
the wild horse and the bison. Either way, cave lions
wound up in caves and cave environments helped preserve their
bones for future excavation by humans, who, at least at
first like, oh, this is a cave line, we found
it in a cave.
Speaker 3 (10:03):
But I assume you're saying that researchers do not believe
the same kind of naming error was made with cave bears.
The cave bears really do seem largely involved with caves.
Speaker 1 (10:13):
Yes, yes, that's the consensus. So you know, what were
cave bears. We talked a little bit about what they
look like already. They were very large bears, comparable to
or even larger than any of the bears we know today,
even the mighty polar bears and Kodiak bears, which depending
on who you're talking to, these are kind of like
the two extant species of bears that are often held
(10:36):
up as the biggest. So male cave bears could range
and wait. One estimate I saw was three fifty to
six hundred kilograms or seven hundred and seventy to three
hundred and twenty pounds. I've also seen like the four
hundred to one thousand kilogram estimate, about eight hundred and
eighty to two two hundred pounds. Again, it's going to vary.
(10:59):
The male were bigger than the females and so forth,
But anyway you cut it, big bears, big heavy bears.
Their weight would have fluctuated depending on where they were seasonally,
where their diet was, what the overall climate happened to be.
But yes, these were very large bears. And therefore, as
you can imagine, not just any cave is going to do.
(11:19):
Cave has to be large enough to hold a bear. Now,
speaking of these caves, I was reading about them a
little bit. I was looking a few different sources. But
I've had this book on my shelf for years and
I hadn't really cracked it open. But it's by one
(11:40):
wolf Dee Storal titled Bear Myth, Animal and Icon. This author,
by the way, I think he's generally more considered an
anthropologist and an ethnobotanist, and I'm to understand his views
have ventured into some areas that may be considered more
esoteric and even controversial, but I don't think any of
that applies to this work. Okay, Anyway, the author here
(12:02):
points to another connection who is kind of similar to
something we discussed I believe in the last episode with
the with the Ohm, a connection between an actual cave
organism and traditions concerning the dragon. There's a cave in
Austria known as Drakenhole or Dragons hole so named because
(12:25):
the copious amounts of cave bear bones in there were
apparently interpreted during the Middle Ages as the bones of dragons.
The cave is located near a place called mix Nitz
and is associated with the legend of the dragon slayer
of mix Nitz. I was looking around. I couldn't find
what felt like a definitive analysis or retelling of this legend.
(12:47):
But I saw some ride ups where it seems like it's,
you know, you, on one level, your typical tale of
a dragon slayer. But it did seem based on the
one telling I found that the dragon slayer here uses
an ingenius trap rather than overt combat to kill the dragon.
Like it has to do with like a sharpened spikes
and left out to gouge into the dragon's flesh and
(13:10):
then it goes off and dies. That sort of thing,
you know, kind of your predator model of overcoming your foe.
Speaker 3 (13:16):
Oh that's my kind of tale. I always love a
monster trap.
Speaker 1 (13:20):
Yeah, so you're probably wondering, Okay, this cave is full
of cave bear bones. How many bones we're talking about?
You know, we're talking about like two or three individuals,
maybe a dozen individuals, you know, maybe a dusty old
set of cave bones near one corner a skull and
the other. No, no, no, we're talking about the bones
of an estimated thirty thousand cave bears. Thirty thousand.
Speaker 3 (13:41):
Wow.
Speaker 1 (13:42):
Yeah. Other bones were apparently also found in this particular cave,
including those those of the cave line apparently, but we're
mostly talking about cave bears here, and in quite an abundance.
Speaker 3 (13:54):
You have to think how long they would have been
accumulating there for it's unbelievable.
Speaker 1 (14:00):
Yeah, yeah, we would be dealing with a situation here
where the bears lived in these caves, hibernated in these caves,
and died in these caves for thousands and thousands of years.
So like recent genetic data apparently indicates that cave beer
populations in Europe, specifically along the Danube River were stable
for a good one hundred thousand years or more. So, yeah,
(14:22):
you're dealing with lots of bears living and dying in
these locations.
Speaker 3 (14:26):
That is incredible.
Speaker 1 (14:28):
Now, the caves, specifically this Austrian cave system, was apparently
excavated during the nineteenth century because the soil found inside
of these caves is rich, was rich in bones and
bear manure, that it accumulated over these vast periods of time,
and they proved usable as phosphate fertilizer, and there was
(14:49):
a shortage during this time period. Storal rites that sixty
trains with fifty cars each were filled with the stuff,
and also points out that a cave near vell Berg, Germany,
was also excavated for its cave bear riches during this
time period. Now, these aren't the only two European caves
that there's evidence of a lot of cave bear activity.
(15:11):
I read in passing examples of caves and for instance
Spain and Romania that also provided a great deal of
cave bear remains. Now speaking to their death in these caves,
because you know, it's one thing to sleep in the cave,
and there is evidence we'll get to that in a second.
There is evidence already of like the bears having lived
(15:32):
in and slept in the caves, but they also died there.
And I've read that it's thought that bears may have
frequently died during hibernation, especially during particularly trying time periods,
which we'll get to here, because if an individual couldn't
put on enough weight heading into winter and or environmental
conditions were particularly dire, they just might not emerge again
(15:55):
in the spring. Plus we already mentioned that in some
cases you might have predators venturing into those caves to
try and find an easy bear to pick off. And
it's any easy mathematics to imagine, like, Okay, if you
have a weakened bear in a hibernation state, one that
might not be surviving the winter anyway, like that's ideal
(16:17):
biomass to pick off. Now. I think everyone's familiar enough
with the fat bear week craze these days to know, yeah,
that bears have to pack it on, and we find
some sport and amusement in figuring out like which bears
are packing on the most and what do extant bears
(16:39):
eat in order to go into hibernation? Well, the answer
is what do you got? They're omnivores. Anything is on
the table, right. Yeah.
Speaker 3 (16:47):
I think a lot of the ones that we're familiar
with are these ones photographed in Alaska. From what I understand,
they're probably going to be eating a lot of like
river fish, like salmon.
Speaker 1 (16:56):
Yeah. Yeah. The cave bears, though, this would have been
a different matter. So research has differed at different times
on whether the bears were strictly herbivores, or if they
were mostly herbivores, at the very least, they seem to
have depended far more on the consumption of plant matter
than pretty much any extant bear, with the obvious exception
(17:19):
of the giant panda. These cave bears would have gone
out and eaten a lot of vegetation, and we see
that reflected in like they're just their anatomy. So I
was looking at the work of Alejandro Perez Ramos at
the University of Malaga in Spain. This would have been
a twenty twenty study. The researcher here points out that
(17:39):
the cave bears were built in such a way. Their
skulls were built in such a way that they could
only chew with their back teeth. So extant bears, the
bears we have today, can chew with the front as
well as the back, and therefore have the correct dental
build to eat vegetation or meat, switching back and forth
(18:01):
between the two depending on what's available. You know, so
if there are a lot of fish on hand, bam
the bear. You know, bears like grizzlies and so forth,
they're good to go. Get in there and eat that meat.
Dead whale. Likewise, get in there, scavenge some of that meat.
Oh what's this? You only have berries? Or oh, somebody
left the door open to their house. You know, they
(18:22):
can make do with what's available. But again not the
case with cave bears. A chemical analysis of cave bear
bones has also revealed a mostly plant based diet. So
the cave bear had evolved to a point at which
there was no going back in a swift manner anyway,
such as the demands brought on by sudden changes in climate,
(18:43):
and this would seem to be a major factor in
their extinction, if not the major factor in their extinction,
And this seems to be the answer that most of
the current research is pointing to. But it also reveals
some other interesting things about them. You know, the build
of their skull here, because they also had much larger
sinuses in exchange for that lack of robust front teeth.
(19:06):
And this is interesting, especially because extant bears are already
famous super smellers. I think if you've ever ventured into
bear territory, you have been warned. You know, don't leave say,
chapstick in your car, because a bear can smell that
and a bear will want to come see what kind
of sweet, delicious fruity food you have hidden away inside
(19:28):
of your automobile.
Speaker 3 (19:29):
Oh, I just imagining the bears going wild over like
the synthetic kinds of fruity flavors that you get in
all these products, Like what is fun bearry? I must
discover exactly.
Speaker 1 (19:41):
Yeah, I mean this is again with something we've touched
on already in this series. You know, like how difficult
or impossible it is for human beings to really put
themselves in the sense world of another organism that has,
you know, a sense array different from our own. And
smell is another one of those areas. So take, for instance,
(20:04):
a bloodhound, a canine. Canines in general, but specifically something
like a bloodhound is already pretty famous for being a
super smeller. That is just dogs in general, like their
sense of smell is just a different part of their being.
You know. You see that when you see a dog
like riding around with its human in a vehicle and
(20:25):
it has its head out the window, right, It's like
it's like all the psychedelics at that moment. And yet
I've seen it estimated that a bear and again not
a cave bear just bears in general, bears we have today.
I've read that their sense of smell is seven times
better than a bloodhound, and that would mean that their
sense of smell is thousands of times more powerful than
(20:48):
a human beings. And yet the cave bear likely had
an even keener sense of smell, if we can even
imagine such a thing. Likely great hearing as well, but
on the other hand, reduced eye sight and a smaller
brain that than you might expect with such a large head.
And I'm suspecting here that you know that would also
have to do with its mode of life at this
(21:11):
point in its evolution, like it's just going around eating
as much vegetation as it can, sifting through these various
sources of vegetation, but maybe not having to be as
clever and opportunistic as a true omnivore would be. But anyway,
all this would seem to be wound up in their
extinction as well, because somewhere around twenty four thousand years ago,
(21:36):
around the time when their age ended, the age of
the cave beer comes to an end, temperatures plummeted. This
would have been the last glacial maximum period cooler tempts
meant less time and less plant matter to bulk up
on before going into hibernation, so the cave bears likely
couldn't keep up. They couldn't bulk up, and again could
(21:57):
not adjust their diet like other bear species. The bear
species that survived these cold times were the ones that
could diversify, that could go in more on the meat
perhaps than they had been And in many cases, yeah,
this would mean that you would have cave bears crawling
into their caves to hibernate with or without young and
simply never getting back up again. I alluded to this earlier,
(22:20):
but yeah, in the caves that they called home, we
do have more than just their bones to speak of them.
So they, like a lot of animals, they ended up
leaving claw marks on the walls in some cases, and
they also dug shallow depressions in the floor, likely as
places to sleep, and you can find images of these
from various European cave systems. You know, they're not especially flashy,
(22:43):
but it's this sort of large bear shaped indention in
the ground. And yeah, many of these remained to this day,
and some of those claw marks, by the way, would
later be incorporated into the cave art of Homo sapiens.
Speaker 3 (22:57):
Oh interesting, Like you mean, like that human made their
art around pre existing claw marks in the walls and
made that part of the art.
Speaker 1 (23:06):
Yeah, yeah, Like I believe that's the case with some
of the art in France's Chauvet caves, where you have
depictions of cave bears, but also evidence of cave bears,
including claw marks. Now speaking of humans there, of course,
there's long been some mystery over exactly what sort of
relationships Theanderthals and Homo sapiens had with the cave bears.
(23:27):
I mean, we're humans. We can't help it. We find
out that we were alive at all during the same
time period, We're like, what about us? How do we
factor into this fascinating and majestic scenario? What were we doing?
And did we ride them? Did we ride them? Did
we worship them? Yeah? There was this much popularized idea
that early humans worshiped cave bears, and it does seem
(23:50):
like there's some potential evidence for this, but apparently this
has long been disputed and sort of largely pushed out
of the way. This would have been the basis for
fictional works like the novel clan of the Cave Bear.
But there's still various mysteries along these lines. You know,
they will never know one d percent what our ancient
ancient ancestors really thought about these creatures. And it's also
(24:13):
easy to simplify what we thought about them that like, oh,
did we worship them? Or did we eat them? Or
did we run from them? And of course, you know,
even our prehistoric ancestors I think would have had the
mental complexity to do all three, depending on where you
are in a given day and so forth, I.
Speaker 3 (24:32):
Seem to I think it's been years now, but I
have a memory of coming across some interesting claims on
the internet about about, like, you know, prehistoric humans and
their specific beliefs regarding bears, And I was like, what's
the source of this, Like what's the evidence for it?
And I could never actually track it down, Like it
seems like there's just a lot of claims floating around
(24:54):
on the internet about about prehistoric humans and bears.
Speaker 1 (24:58):
Yeah, I mean, I guess I one level, Well, it's
like we do acknowledge the fact that human ancient humans
and prestark humans, they acknowledged these large creatures in their
natural world. Yeah, they had relationships with various creatures in
their natural world, and they seem to have superstitious and
or mythological ideas about them. We talked about some of
(25:21):
the earliest images and past episodes of the show where
these people would combine human and animal imagery into a
single entity. Though exactly what is meant by that, we're
not sure.
Speaker 3 (25:34):
Yeah, this actually came up in a listener mail I
did while you were out recently. A listener wrote in
about our episode on the loewenmine, you know this carving
that has been interpreted as depicting a sort of a
human body with the lion's head, though there's some dispute
about whether that's the correct interpretation of what it's supposed
to be, but that seems like a common interpretation, and
(25:55):
so yeah, this raised these interesting questions about like when
did we start forming ideas about creatures that did not
exist in nature.
Speaker 1 (26:04):
Yeah, it is hard for us to figure out the
exact artistic content. For example, going back to the Chouve
Cave in France, this is a cave that contains human
illustrations of cave bears among other animals, copious amounts of
cave bear bones, cave bear claw marks on the walls,
it has floor depressions made by the bears. But one
(26:25):
chamber here also apparently has a single cave bear skull
that seemed to have been placed on a stone slab
in the center of the chamber. But it's impossible to
say why this is the case, like were they worshiping
the bear or a particular bear, was it just a curiosity,
was it some form of superstition or what did it
(26:47):
represent some like tangible connection between these people and their
way of life to the bear or was it something
more abstract. Now apparently we do know from some skeletal
evidence this would be in rare cases some evidence of butchery.
And also there may have been another example that was
more directly tied to some sort of like hunting weapon,
(27:09):
but at least butchery evidence that shows that humans at
least sometimes hunted or killed or at least butchered cave bears,
but is pointed out in Andrew Curry's twenty ten Fate
of the Cave Bear article ver Smithsonian dot Com, citing
anthropologist Eric Trinkhaus, it's unlikely that human hunting impacted the
(27:30):
cave bear's existence or led to its extinction. Trenkiles points
out faced many Illethal threats during this time, and the
cave bear, if provoked, was certainly one of them. I mean,
just because it doesn't really eat meat doesn't mean that
an animal this big and this ferocious could not kill you.
(27:50):
So it's unlikely, according to this expert, that humans tangled
with it all that much. But they might have sometimes
gone after hibernating bears or hunted them in other isolated
events for one reason or another. So it happened, but
probably not all that often. Still there's again there's a
(28:12):
lot of room for some level of supernatural consideration of
the cave bear. Going back to the work of a
wolf Storrel in his book, he writes that Shirley quote,
any animal that can go in and out of the
womb of the Great Goddess without incident is surely also
a guardian of fertility and birth. Again, he's predominantly an
anthropologist and athnobotanist. So this is the book in its entirety,
(28:36):
is more about how we have thought about bears throughout history,
even getting into at least short entries on ewoks and
Fozzy Bear later on. But particularly he points to other
traditions along these lines of a female bear shaman character
a lady of the caves, and also reflects on up
(28:57):
to traditions of the ancient Greek god is Artemis, whose
domain includes both the hunt and childbirth and is also
associated with bears. M interesting, but of course we just
get increasing way into the domain of speculation in this. Yeah. Again,
I think most experts kind of dismissed the notion that
that that early Homo sapiens worshiped the cave bear to
(29:22):
any significant degree.
Speaker 3 (29:24):
By dismissed, I assume you mean not that they rule
it out, but they just say, we don't have super
strong evidence.
Speaker 1 (29:30):
Yeah. Yeah, that's the That's that's what I get from it,
because I think it would be silly to say, you know,
our ancestors didn't notice these things at all, or they
didn't care about like it seems like there's there's room
for there to be that connection. But do we have
the evidence of it.
Speaker 3 (29:45):
Yeah, it's just one of those mysteries. There's a lot
about the culture of prehistoric humans that's difficult to know
based on the evidence we have.
Speaker 1 (29:52):
Yeah, real quick in passing before we move on to
more important matters, I will say that Storrel has one entry,
actually a whole page in the book on gummy bears,
also apparently known as dancing bears, which apparently have Germanic
origins going back to nineteen twenty two and are quote
now part of the German way of life. Okay, he
(30:14):
doesn't get into this issue in this twenty eighteen book,
but I wonder what he would make of the increasing
use of bear shaped gummies as a delivery system for
CBD and cannabis and cannabis related products. And even before this,
I think, going back in the nineties, they were being
used in some cases to deliver vitamins, and today you
can get all manner of supplements in them. So like
(30:35):
the dancing bear kind of becomes this shumnistic item. Perhaps
once more you know that's funny, but no real connection
to the cave bear there.
Speaker 3 (30:45):
Sorry, What would you make also about the equivalency of
worms there, and the fact that the gummy worms are
typically larger than the bears. That suggests something about Shai
lude to me.
Speaker 1 (30:54):
Ah, yes, solid point. For some reason, I've gotten to
the point where I accept a bear shaped gummy is
an appropriate shape for some sort of chemical delivery system
as opposed to some of the other shape Like for
some reason, a worm is too silly for me, Like
it just seems like, why, what what are you doing?
It's ridiculous. Responsible kids eat candy worms, but bears, bears?
(31:19):
I don't know, Like are we at the point where
I just you know, we don't. I guess we don't
go through a lot of gummy bears. But it just
it's just like I would be suspicious of a gummy bear.
I would be like, be careful, you don't know what's
in that bear. But a pure gummy worm, you're saying
you're more likely to trust that, I guess, But now
I'm second guessing myself. I don't know. I'm just suspicious
(31:39):
of the whole gummy genre.
Speaker 3 (31:51):
Okay, well, I've got one more thing I want to
talk about. So we've discussed the ways that animals adapt
to cave environments, but I wanted to talk about a
fascinating idea I came across in a spielology paper, which is,
what if some of the natural holes and recessions in
rock that we call caves were actually formed in part
(32:15):
not by standard inorganic processes like you know, lava tube
solidification in volcanic rock or the dissolution of limestone by
water instead were formed in part by animals essentially eating
their way through the rock. Let's look at a paper,
So my source here is by Charles A. Lundquist and
(32:37):
William W. Varnado Junior, called Salt Ingestion Caves, published in
the International Journal of Spielology in the year two thousand
and six. So the authors kick things off by pointing
out that, of course animals need salt to survive. It
is a basic requirement in the body. Regular table salt
(32:57):
is known chemically as sodium chloride, and when we ingest it,
our bodies use both the sodium ions and the chloride
ions from that molecule for a number of functions. Salt
is necessary for our muscles to function properly, like we
need sodium so muscles can contract and relax. It's used
(33:18):
in our nervous systems to conduct impulses. It's used for
all kinds of things throughout the body, and most humans
get way more of it than we need because we
add supplemental salt to our food for taste. But of
course wild animals don't have the kind of ready access
to supplemental salt that we do in the wild. Carnivores
can usually get the salt they need by eating the
(33:41):
flesh of other animals, which naturally contains a good bit
of it, but for herbivores getting enough salt can be difficult.
The sodium content of most terrestrial plants is quite low,
and since ancient times, humans have noticed that animals, especially herbivores,
sometimes gather at what are called salt licks, or more broadly,
(34:03):
mineral licks, places where there are rocks or soils that
animals can consume in some way to supplement the mineral
content of their diet, including minerals such as sodium salt.
This can include a range of behaviors in the wild,
like licking salty rocks on a mountainside, eating exposed clays
(34:25):
or other sediments that have a desirable mineral content. And
because herbivores are drawn to these salty rocks and soils,
hunters have long known about them as good places to
find game. So what does this have to do with caves? Well,
the author's rite quote large vertebrate herbivores, when they find
a salt bearing layer of rock in a cliff face,
(34:47):
can over generations produce sizeable voids where they have removed
and consumed salty rock. These cavities that humans can enter
can have the characteristics of a cave as defined locally.
So that last sentence meaning that, you know, whatever people
call a cave, You know that varies from place to place,
but usually it means like a void in the rock
(35:09):
that's large enough for a person to go into to enter.
And those types of voids can indeed be created by
animals removing the rock by eating it.
Speaker 1 (35:21):
Wow, So you're saying that in some cases a cave
is naturally formed over geologic time by rain, water and
so forth. Other times a deer just licks it until
it's right a deer licked it into the side of
a mountain.
Speaker 3 (35:34):
That appears to be the case, according to these authors.
So they look at several case studies in the paper.
One is a site referenced in some literature about the
Altai Mountains in Asia. The authors are talking about reports
from surveys of the Altai Mountains, specifically of a mountain
bearing shale formations near the confluence of the Kan River
(35:57):
and the Charch River. Apparently, the shale here is very salty,
and they quote a commentary by an author named Carl
Friedrich von Eltibor from eighteen twenty six, who writes of
the shale quote, all livestock of the Kalmuks find this rock,
which gives the mountain an ash gray appearance, very desirable,
(36:19):
and consume it in not small amounts, so that one
not infrequently finds grottos built in this way. Of course,
a grotto refers to a small cave, and this author
mentions that both domestic and wild animals come to this
mountain to eat the shale. Another example they mention is
a place in the United States. It's called rock House Cave.
(36:43):
It's a cave situated within the rock of a small
bluff in the US state of Mississippi. They say that
the entrance is roughly ten feet wide, but then the
cave actually widens once you go inside. It roughly doubles
in width. It's just about tall enough for an adult
to stand up, and it reaches about fifteen feet deep
into the bluff. And they say the surrounding rock is
(37:05):
mostly what the authors characterize as a soft, fine grained sandstone.
They say it is of the Kataboulah formation, and it's
got a significant amount of sodium chloride in it. The
authors also say there's no evidence that water solution caused
the formation of this cave, and instead it appears that
it was caused by many generations of animals removing the
(37:28):
walls by licking. They say there is a rough surface
on the walls that seems to quite possibly have been
created just by animals licking it away over time. They
say it was probably first wild deer and possibly bison
that opened this cave up, and then maybe cattle later.
Speaker 1 (37:44):
Oh wow.
Speaker 3 (37:45):
But the most amazing example they cite is one from
eastern Africa. This so, there's an extinct volcano on the
border between Kenya and Uganda. This volcano is called Mount
elgon or Elgonyi, and on the side of this mountain
there are what I've read described elsewhere as ballroom sized caves,
(38:08):
large sizable caves that appear to have been at least
in part excavated by elephants. Elephants inside caves, Yes, yes,
so there there is some question about the role of
the elephants in creating the caves, but there is no
question that the cave that the elephants do go into
the caves and consume rocks that has been directly observed.
(38:31):
That's the thing that happens. So the most famous of
the Mount Elgon caves is known as Katoomb Cave k
t u M and the authors propose that these caves
were formed in part by water solution, but also in
part because wild herbivores literally eat the rocks away and
remove them from the caverns.
Speaker 1 (38:52):
Yeah, this is this is amazing. I have I've actually
seen footage of this. I don't remember which elephant documentary
I saw this in Problem maybe More and One watched
a lot of elephant documentaries at one point, and my
son's upbringing when he was super into elephants. But it's
it is amazing to behold. And these are large caves,
you know, starters elephants have to fit in them. But yeah,
(39:15):
I think ballroom seems appropriate based on the footage as
I remember it, because these look like the kind of
caverns that you might have filmed like a B movie
in or perhaps an episode of Star Trek took place in. Yeah, yeah,
I can see that.
Speaker 3 (39:29):
Now elephants are not the only animals that go into
these caves to eat the to like consume parts of
the walls and eat the rocks. Apparently, also buffaloes, antelopes,
and sometimes monkeys have been observed to go into the
caves and eat some of the some of the soft
rocks that line the walls. The authors say specifically Katoomb
Cave to give you a better idea about the size
(39:51):
of one of the big caves. Here, they say that
the rock face that the elephants generally go to to
get to get their minerals from is about one hundred
and sixty meters into the mountain from the entrance, so
that's a deep cave. And they say that what happens
is the elephants go in and they usually loosen pieces
(40:12):
of rock from the walls of the cave with their tusks,
so they're like digging against the walls with their tusks.
These pieces fall to the floor, and then they pick
up the pieces with their trunks, and then they put
the piece in their mouth and chew it up crush
it with their teeth. Now, what was not fully resolved
at the time of this paper, and from what I
can tell, has still not been fully resolved, is what
(40:35):
are the relative contributions of the different processes to how
large the caves are like, are the caves predominantly formed
by inorganic solution and erosion of the rock by water
flow and then supplemented is that excavation supplemented by elephants
and other animals removing some amount of rock? Or are
(40:57):
the elephants and other animals primarily respectible for hollowing out
the caves and there's just some solution by water going on?
Also what role may have been played by like human
mining and other factors. So the authors look at several
analyzes of this, and they quote one researcher named Ian
Redmond who did a study of the cave in nineteen
(41:19):
eighty four. Redmond did several months of field observations, watching
the elephants and analyzing even the mineral content of their droppings.
Redmond wrote, quote, the volume of Katumb cave is on
the order of one point three million gallons or about
five million liders. If for the sake of conservative argument,
(41:40):
we suppose that elephant excavations averaged just one quart per week,
it would have taken only one hundred thousand years for
them to dig Katum. The theory of elephants, spieleogenesis cave
creation is entirely plausible. Wow, yeah, amazing to consider. The
authors also they cite another study, this one by researchers
(42:02):
named Donald McFarlane and Joyce Lundberg. This was from two
thousand and four where after field observations, these researchers suggested
a multi step process for cave formation that would go
like this. They summarize it as follows. So, first of all,
there is a cliff that forms. There's like water flowing
(42:23):
off of the mountain they say, off of a cap
rock layer, and it erodes some material from underneath. Then
after that they say that some more material clay sized
material sediment is removed from the floor of the cave
by groundwater sapping. And then they also say more mass
(42:43):
is removed from the cave by animal excavation. And then
at some point there are collapses within the cave. They write,
quote collapse of overlying beds makes piles of broken material
which are removed by action of water and animal geoff
rock eating. And then finally they say step four is repeat.
(43:05):
This whole process repeats over and over again. So they're
saying that it's a combination of material being removed by
water flow and then the cavern collapsing as material is
removed and supporting walls are removed, and then animals also
remove parts of the walls and remove some of the
collapsed material from above, and it just keeps going on.
Speaker 1 (43:27):
Like that because those animals, they don't care about the
structural integrity of the cave. They just want to get
that salt right. It's all they want is they're fix now.
Speaker 3 (43:36):
Ultimately, the authors of this analysis, McFarlane and Lundberg, were
unable to say what the relative masses of rock removed
by water versus geophagi were, but they seem to believe
that the amount removed by the animals was significant. And
then coming back to the parent paper, the one by
Lundquist and Varnido Junior, they bring up something that was
(43:58):
interesting when thought about. When I was thinking about it,
in parallel to our discussion of batguana, is a kind
of alternative sunlight or base of the food chain in
deeper limestone caves. Speaking of the Mount Elgun caves, the
authors here note that quote a common feature in most
of the larger caves is the quantity of dung deposited
(44:19):
by beasts which have come to the caves from time
immemorial to lick or otherwise consume the agglomerate walls. Traces
of elephants using the caves are most common, and their
tusk marks are clearly recognizable where they have gouged the rock.
So actually a couple interesting parallels there, the connection to
the seeing where the elephants with their tusks have like
(44:42):
cut gashes in the rock in the walls of the caves,
kind of like the marks on the cave walls left
by the cave bears. But also all the poop, all
the poop of all the visitors accumulating over the thousands
of years.
Speaker 1 (44:55):
Yeah, it's crazy, and you know all this also reminds
me of episode we did a while back on giant sloths,
a particular variety of giant sloth that would have dug
itself kind of a burrow into a like deep into burrow,
creating eventually over time as they reuse these spaces a
(45:16):
kind of tunnel in the earth.
Speaker 3 (45:18):
Funny you should mention that because the fourth case study
that the authors bring up in this paper is evidence
related to what's called Mylodon Cave in Patagonia in Chile.
They say that it is possible that this is a
case of cave formation by salt ingestion long ago, this
time implicating extinct giant ground sloths. This is fully speculative,
(45:41):
but they do highlight this as a possibility, explaining where
this cave came from.
Speaker 1 (45:45):
Wow.
Speaker 3 (45:46):
But to come back and conclude the look at the
Mount Elgon caves. So they say, what we do know
is that animals come to these caves to consume mineral
laden soil and rocks, so these caves could be thought
of as massive salt licks or mineral licks. There are
generally no permanent streams running out of the caves, so
that that's not an option for removal of cave material
(46:10):
by like permanent water passage. Some water does appear to
run out of the caves during flooding events, but how
much rock material is removed during these events in this
way is uncertain, so we still in the end don't
know the relative amounts. We don't know how much of
the cave formation is due to water solution versus how
(46:34):
much is due to animals eating the rock. But they
think that both processes contribute, and their judgment in the
end is that the contribution of the elephants is the
primary process.
Speaker 1 (46:47):
Wow.
Speaker 3 (46:47):
Either way, it's amazing to imagine elephants going into caves
to eat the rocks.
Speaker 1 (46:52):
Yeah, it's amazing. And you know, we shouldn't cast too
much judgment. Like you mentioned earlier, humans very often don't
have to worry about getting enough salt we eat at
a restaurant. Once we get like a colossal salt bomb, right,
we get we get more than enough salt. We get
an unhealthy amount of salt ingested into our bodies. But
(47:14):
if we didn't have those food sources, we might be
out there looking the sides of mountains just like these
various herbivores are. Assuming we also didn't eat copious amounts
of meat on top of that, which is another factor
to consider here.
Speaker 3 (47:30):
Yeah, all right, well does that do it for this
exploration of caves. I'm sure we'll be back in the future.
Speaker 1 (47:36):
Yeah, there's all I mean, we've we've covered caves in
the past. Yeah, we'll be back in the future. And
there are a number of fascinating cave organisms that we
didn't cover in these episodes. And if you have favorites
right in, we'd love to hear from you, because we
could always venture back into the caves. You know, we
don't reside there all the time, but we we go
in from time to time in order to discuss something interesting.
(47:58):
All right, as as usual, we'll just remind you that
Stuff to Blow Your Mind is primarily a science and
culture podcast, with core episodes on Tuesdays and Thursdays, listener
mail on Mondays, short form episode on Wednesdays, and on Fridays.
We set aside most serious concerns. Just talk about a
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(48:21):
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(48:42):
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(49:03):
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Speaker 3 (49:05):
Huge thanks as always to our excellent audio producer JJ Posway.
If you would like to get in touch with us
with feedback on this episode or any other, to suggest
a topic for the future, or just to say hello,
you can email us at contact at stuff to Blow
your Mind dot com.
Speaker 2 (49:27):
Stuff to Blow Your Mind is production of iHeartRadio. For
more podcasts from my heart Radio, visit the iHeartRadio app,
Apple Podcasts, or wherever you listen to your favorite shows.
Hey, welcome to Stuff to Blow Your Mind. My name
is Robert Lamb. Today is Saturday, so we have a
vault episode for you. This is going to be part
four of our series, Part four of four titled Life
in the Hypogenean World. We're gonna wrap this one up today,
so let's dive right in. This originally published three fourteen,
twenty twenty four.
Speaker 2 (00:30):
Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.
Speaker 1 (00:40):
Hey, welcome to Stuff to Blow your Mind. My name
is Robert.
Speaker 3 (00:42):
Lamb, and I am Joe McCormick, and we're back with
the fourth and final part of our series on cave
biology and cave environments. If you haven't listened to the
other parts already, this will probably be a richer experience
if you go back and check those out first. In
the previous parts, we talked about some of the common
characteristics of cave environments, especially as they pertain to the
(01:05):
life forms that might inhabit caves. We talked about the
different types of organisms you find in caves, the ones
that are fully cave adapted versus the ones that are
only visitors. We talked about cave adapted organisms such as
the blind Mexican cavefish, also known as the Mexican tetra
the ome, which is a type of cave salamander found
(01:27):
in the Dynaric Alps. We talked about bat guano, We
talked about snakes that hide in caves and attack bats
as they come and go. We got into a lot
of great stuff, and today we're here to round out
the series.
Speaker 1 (01:41):
Yeah, with a lot of like a lot of our
multi part episodes, it's kind of like the first episode
is kind of like a lot of the initial information
you need, and then the second episode this is where
you find some of the core stuff that attracted us
to the topic to begin with. Part three we kind
of like fill in with a little more data some
other interest entries in said series in the fourth episode
(02:03):
or whatever the final episode happens to be. Generally, that's
where it's like, what's left. What's the thing that came
up in our research that we didn't know we were
going to be excited about, or or in some cases,
maybe what's the weird tangential connection that also came up
or we found ourselves drifting into in the in our journey. Oh,
I think that's a good way to characterize it. So
(02:25):
what have you got, rob Well? I mentioned this earlier.
I forget which of the earlier episodes, but I mentioned
the extinct cave bear in Passing, and I would just
kind of kept touching back in on the subject as
we were working on the other episodes, and finally I
was like, Yeah, we need to go in a little
deeper and talk about what is ultimately like a really
fascinating organism. There have been disagreements and mysteries regarding it,
(02:49):
and it is an organism that, while no longer with us,
does overlap with our ancestors. You know, it was an
ice age creature. Include did here for you, Joe a
reconstruction and image of what one of these bears would
have looked like potentially, And in a bit I'll get
into like what are some of the main anatomical features?
(03:11):
But just looking at you can tell this is a
very huge bear. If it doesn't look that different from say,
like a large you know, grizzly bear, brown bear of
some sort. Coloration is brownish, but one might notice that
the head is enormous. It has a much bigger head
than one might expect, certainly on an extant bear.
Speaker 3 (03:33):
Yeah, it looks a lot like a grizzly. Though I'm
no bear expert, it does appear to me in this
reconstruction to have a somewhat shorter snout and the and
the sort of boxier.
Speaker 1 (03:44):
Head boxier and I'm to understand would have been what
would have appeared wider as well. So we're talking about
Ursus spilaeus. It's a member of the Ursus genus, alongside
the brown bear, which includes grizzly subspecies, among others, the
polar bear, the American black bear, and the Asian black bear.
(04:07):
That means it's naturally a member of the larger Ursudae family,
which also includes the likes of giant pandas, short face
bears and others.
Speaker 3 (04:16):
Oh, I didn't realize pandas were technically in that family.
Speaker 1 (04:20):
Yeah, yeah, Like one of the interesting things about pandas
is that pandas are herbivores for the most part, but
they still have a carnivores digestive system, and they still
have like carnivore jeans, So they're pretty fascinating in their
own right. You know, it's easy to overlook how interesting
pandas are, especially if you go to a zoo and
(04:42):
you see one in captivity that is probably not doing
much other than sleeping or eating pamboo.
Speaker 3 (04:48):
The last time I went to a zoo, the thing
I saw that filled me with the most joy was
actually vicarious joy through a panda when I saw the
feeders through some new bamboo into the enclosure, and the
panda went up to the pile of bamboo and literally
just flopped in. It, just flopped down in its food, like, ah,
give it to me.
Speaker 1 (05:07):
It is literally their favorite thing, Yeah, rolling around in it.
More on this connection to the panda in a minute here,
but yeah, the cave bear when extinct. I do want
to highlight that the exact timing for this depends on
exactly what sources and what evidence you're looking at. I've
seen between twenty eight and twenty seven thousand years ago
(05:28):
during the last glacial maximum. I've seen twenty four thousand
years ago, and in some sources, some of the older sources,
you also see fifteen thousand years ago cited as an
extinction point. But I believe an earlier point in twenty eight,
twenty seven, maybe twenty four is generally favored by scientists today.
That's generally the range. The broader range in which I'm
(05:49):
tending to see the numbers and the sources I was
looking at. And the interesting thing about the cave bear, too,
is that this animal is a recent enough denizen of
the planet that we have been able to study its
soft tissue in addition to its bones, and it's actual
you know, we're able to study like the chemical composition
of its bones. There was even a frozen specimen discovered
in twenty twenty, I believe, and we've been able to
(06:10):
sequence its genome, so we're able to learn a fair
amount about what they were and what they did, though
certain mysteries remain about, you know, their exact lifestyles, their
interactions with other organisms and so forth. Well, let's come
back to the cave theme, right, because that's the umbrella
in which we're just under which we're discussing the cave bear. Here,
(06:32):
we're of course, not talking about an obligate cave dweller.
This is not a blind, hairless bear living in the depths,
as I'm suddenly realizing. As interesting as that might be,
I'm assuming some fantasy weaver has done something like that before.
But now this would have had at best been a
troglophilic creature.
Speaker 3 (06:52):
Okay, so the troglophilic creature enjoys visiting caves. It may
visit caves for a number of reasons, but it doesn't
live there permanently, and it's not biologically adapted to full
time life in the caves.
Speaker 1 (07:05):
Yeah, Like it's not just hanging out in there all
the time, eating bats or anything. But you know, the
cave moniker can be confusing with a lot of these
species because of course we speak of cave men either
in terms of prehistoric Homo sapiens or Neanderthals. Though even
with the latter, who certainly did utilize cave environments as
did humans, they used open air sites for various activities
(07:26):
as well, it seems, so it's not like they just
lived in caves or or and they're certainly not creatures
that were obligate cave dwellers. Plus, the cave moniker sometimes
has as much to do, if not more, to do
with the places where we've discovered the remains, because, as
we've touched on before, I think in this series and
probably in general, like caves are a great place for
(07:49):
remains to be preserved. To some degree, I saw a
paper that was quoting an expert on cave bears. It
was like the bears slept in caves and they had
the good fortune to die in them, something to that effect.
You know, they're like, fortunately for us, they died in
caves a lot, and so we have a lot of
remains to look at. But anyway, just because we have
(08:10):
come to refer to a creature as a cave animal,
it doesn't necessarily mean that it lived in caves. The
main example of this era would be the cave lion
or Panthera spileea, also known as the step lion, which
is now understood to have largely lived in open areas
and possibly woodlands. But we know them a lot of
(08:31):
We know a lot about them from skeletal remains found
in caves, thus cave lions.
Speaker 3 (08:37):
But it's not thought that that's where they spent a
huge amount of their time. It's more just like we
happen to have gotten some remains from caves.
Speaker 1 (08:45):
That's right, yeah, I mean there are remains found in
caves are apparently best understood as on one hand, perhaps
the accumulations or middens of extinct cave hyenas. These this
was all This is also known as the Ice Age
spotted hyena that would have scavenged carcasses and brought them
back to the caves where they lived, or at least
(09:07):
the cave openings where they lived. These would have been
This is an example of something that did live in
caves based on our current understanding, and so they would
have hoarded, scavenged, and killed prey in such places, while
also competing apparently with Neanderthals for some of the same
cave environments. Oh interesting, But back to the cave lion.
It is also thought that they might have ventured into
(09:28):
caves during the winter, especially in search of hibernating bears
that might in some cases be easier to pick off,
especially if they were desperate for the food. And they
also may have periodically entered caves in order to steal
food away from cave hyenas, though to be sure, it
seems like they largely preyed on larger wild herbivores like
(09:49):
the wild horse and the bison. Either way, cave lions
wound up in caves and cave environments helped preserve their
bones for future excavation by humans, who, at least at
first like, oh, this is a cave line, we found
it in a cave.
Speaker 3 (10:03):
But I assume you're saying that researchers do not believe
the same kind of naming error was made with cave bears.
The cave bears really do seem largely involved with caves.
Speaker 1 (10:13):
Yes, yes, that's the consensus. So you know, what were
cave bears. We talked a little bit about what they
look like already. They were very large bears, comparable to
or even larger than any of the bears we know today,
even the mighty polar bears and Kodiak bears, which depending
on who you're talking to, these are kind of like
the two extant species of bears that are often held
(10:36):
up as the biggest. So male cave bears could range
and wait. One estimate I saw was three fifty to
six hundred kilograms or seven hundred and seventy to three
hundred and twenty pounds. I've also seen like the four
hundred to one thousand kilogram estimate, about eight hundred and
eighty to two two hundred pounds. Again, it's going to vary.
(10:59):
The male were bigger than the females and so forth,
But anyway you cut it, big bears, big heavy bears.
Their weight would have fluctuated depending on where they were seasonally,
where their diet was, what the overall climate happened to be.
But yes, these were very large bears. And therefore, as
you can imagine, not just any cave is going to do.
(11:19):
Cave has to be large enough to hold a bear. Now,
speaking of these caves, I was reading about them a
little bit. I was looking a few different sources. But
I've had this book on my shelf for years and
I hadn't really cracked it open. But it's by one
(11:40):
wolf Dee Storal titled Bear Myth, Animal and Icon. This author,
by the way, I think he's generally more considered an
anthropologist and an ethnobotanist, and I'm to understand his views
have ventured into some areas that may be considered more
esoteric and even controversial, but I don't think any of
that applies to this work. Okay, Anyway, the author here
(12:02):
points to another connection who is kind of similar to
something we discussed I believe in the last episode with
the with the Ohm, a connection between an actual cave
organism and traditions concerning the dragon. There's a cave in
Austria known as Drakenhole or Dragons hole so named because
(12:25):
the copious amounts of cave bear bones in there were
apparently interpreted during the Middle Ages as the bones of dragons.
The cave is located near a place called mix Nitz
and is associated with the legend of the dragon slayer
of mix Nitz. I was looking around. I couldn't find
what felt like a definitive analysis or retelling of this legend.
(12:47):
But I saw some ride ups where it seems like it's,
you know, you, on one level, your typical tale of
a dragon slayer. But it did seem based on the
one telling I found that the dragon slayer here uses
an ingenius trap rather than overt combat to kill the dragon.
Like it has to do with like a sharpened spikes
and left out to gouge into the dragon's flesh and
(13:10):
then it goes off and dies. That sort of thing,
you know, kind of your predator model of overcoming your foe.
Speaker 3 (13:16):
Oh that's my kind of tale. I always love a
monster trap.
Speaker 1 (13:20):
Yeah, so you're probably wondering, Okay, this cave is full
of cave bear bones. How many bones we're talking about?
You know, we're talking about like two or three individuals,
maybe a dozen individuals, you know, maybe a dusty old
set of cave bones near one corner a skull and
the other. No, no, no, we're talking about the bones
of an estimated thirty thousand cave bears. Thirty thousand.
Speaker 3 (13:41):
Wow.
Speaker 1 (13:42):
Yeah. Other bones were apparently also found in this particular cave,
including those those of the cave line apparently, but we're
mostly talking about cave bears here, and in quite an abundance.
Speaker 3 (13:54):
You have to think how long they would have been
accumulating there for it's unbelievable.
Speaker 1 (14:00):
Yeah, yeah, we would be dealing with a situation here
where the bears lived in these caves, hibernated in these caves,
and died in these caves for thousands and thousands of years.
So like recent genetic data apparently indicates that cave beer
populations in Europe, specifically along the Danube River were stable
for a good one hundred thousand years or more. So, yeah,
(14:22):
you're dealing with lots of bears living and dying in
these locations.
Speaker 3 (14:26):
That is incredible.
Speaker 1 (14:28):
Now, the caves, specifically this Austrian cave system, was apparently
excavated during the nineteenth century because the soil found inside
of these caves is rich, was rich in bones and
bear manure, that it accumulated over these vast periods of time,
and they proved usable as phosphate fertilizer, and there was
(14:49):
a shortage during this time period. Storal rites that sixty
trains with fifty cars each were filled with the stuff,
and also points out that a cave near vell Berg, Germany,
was also excavated for its cave bear riches during this
time period. Now, these aren't the only two European caves
that there's evidence of a lot of cave bear activity.
(15:11):
I read in passing examples of caves and for instance
Spain and Romania that also provided a great deal of
cave bear remains. Now speaking to their death in these caves,
because you know, it's one thing to sleep in the cave,
and there is evidence we'll get to that in a second.
There is evidence already of like the bears having lived
(15:32):
in and slept in the caves, but they also died there.
And I've read that it's thought that bears may have
frequently died during hibernation, especially during particularly trying time periods,
which we'll get to here, because if an individual couldn't
put on enough weight heading into winter and or environmental
conditions were particularly dire, they just might not emerge again
(15:55):
in the spring. Plus we already mentioned that in some
cases you might have predators venturing into those caves to
try and find an easy bear to pick off. And
it's any easy mathematics to imagine, like, Okay, if you
have a weakened bear in a hibernation state, one that
might not be surviving the winter anyway, like that's ideal
(16:17):
biomass to pick off. Now. I think everyone's familiar enough
with the fat bear week craze these days to know, yeah,
that bears have to pack it on, and we find
some sport and amusement in figuring out like which bears
are packing on the most and what do extant bears
(16:39):
eat in order to go into hibernation? Well, the answer
is what do you got? They're omnivores. Anything is on
the table, right. Yeah.
Speaker 3 (16:47):
I think a lot of the ones that we're familiar
with are these ones photographed in Alaska. From what I understand,
they're probably going to be eating a lot of like
river fish, like salmon.
Speaker 1 (16:56):
Yeah. Yeah. The cave bears, though, this would have been
a different matter. So research has differed at different times
on whether the bears were strictly herbivores, or if they
were mostly herbivores, at the very least, they seem to
have depended far more on the consumption of plant matter
than pretty much any extant bear, with the obvious exception
(17:19):
of the giant panda. These cave bears would have gone
out and eaten a lot of vegetation, and we see
that reflected in like they're just their anatomy. So I
was looking at the work of Alejandro Perez Ramos at
the University of Malaga in Spain. This would have been
a twenty twenty study. The researcher here points out that
(17:39):
the cave bears were built in such a way. Their
skulls were built in such a way that they could
only chew with their back teeth. So extant bears, the
bears we have today, can chew with the front as
well as the back, and therefore have the correct dental
build to eat vegetation or meat, switching back and forth
(18:01):
between the two depending on what's available. You know, so
if there are a lot of fish on hand, bam
the bear. You know, bears like grizzlies and so forth,
they're good to go. Get in there and eat that meat.
Dead whale. Likewise, get in there, scavenge some of that meat.
Oh what's this? You only have berries? Or oh, somebody
left the door open to their house. You know, they
(18:22):
can make do with what's available. But again not the
case with cave bears. A chemical analysis of cave bear
bones has also revealed a mostly plant based diet. So
the cave bear had evolved to a point at which
there was no going back in a swift manner anyway,
such as the demands brought on by sudden changes in climate,
(18:43):
and this would seem to be a major factor in
their extinction, if not the major factor in their extinction,
And this seems to be the answer that most of
the current research is pointing to. But it also reveals
some other interesting things about them. You know, the build
of their skull here, because they also had much larger
sinuses in exchange for that lack of robust front teeth.
(19:06):
And this is interesting, especially because extant bears are already
famous super smellers. I think if you've ever ventured into
bear territory, you have been warned. You know, don't leave say,
chapstick in your car, because a bear can smell that
and a bear will want to come see what kind
of sweet, delicious fruity food you have hidden away inside
(19:28):
of your automobile.
Speaker 3 (19:29):
Oh, I just imagining the bears going wild over like
the synthetic kinds of fruity flavors that you get in
all these products, Like what is fun bearry? I must
discover exactly.
Speaker 1 (19:41):
Yeah, I mean this is again with something we've touched
on already in this series. You know, like how difficult
or impossible it is for human beings to really put
themselves in the sense world of another organism that has,
you know, a sense array different from our own. And
smell is another one of those areas. So take, for instance,
(20:04):
a bloodhound, a canine. Canines in general, but specifically something
like a bloodhound is already pretty famous for being a
super smeller. That is just dogs in general, like their
sense of smell is just a different part of their being.
You know. You see that when you see a dog
like riding around with its human in a vehicle and
(20:25):
it has its head out the window, right, It's like
it's like all the psychedelics at that moment. And yet
I've seen it estimated that a bear and again not
a cave bear just bears in general, bears we have today.
I've read that their sense of smell is seven times
better than a bloodhound, and that would mean that their
sense of smell is thousands of times more powerful than
(20:48):
a human beings. And yet the cave bear likely had
an even keener sense of smell, if we can even
imagine such a thing. Likely great hearing as well, but
on the other hand, reduced eye sight and a smaller
brain that than you might expect with such a large head.
And I'm suspecting here that you know that would also
have to do with its mode of life at this
(21:11):
point in its evolution, like it's just going around eating
as much vegetation as it can, sifting through these various
sources of vegetation, but maybe not having to be as
clever and opportunistic as a true omnivore would be. But anyway,
all this would seem to be wound up in their
extinction as well, because somewhere around twenty four thousand years ago,
(21:36):
around the time when their age ended, the age of
the cave beer comes to an end, temperatures plummeted. This
would have been the last glacial maximum period cooler tempts
meant less time and less plant matter to bulk up
on before going into hibernation, so the cave bears likely
couldn't keep up. They couldn't bulk up, and again could
(21:57):
not adjust their diet like other bear species. The bear
species that survived these cold times were the ones that
could diversify, that could go in more on the meat
perhaps than they had been And in many cases, yeah,
this would mean that you would have cave bears crawling
into their caves to hibernate with or without young and
simply never getting back up again. I alluded to this earlier,
(22:20):
but yeah, in the caves that they called home, we
do have more than just their bones to speak of them.
So they, like a lot of animals, they ended up
leaving claw marks on the walls in some cases, and
they also dug shallow depressions in the floor, likely as
places to sleep, and you can find images of these
from various European cave systems. You know, they're not especially flashy,
(22:43):
but it's this sort of large bear shaped indention in
the ground. And yeah, many of these remained to this day,
and some of those claw marks, by the way, would
later be incorporated into the cave art of Homo sapiens.
Speaker 3 (22:57):
Oh interesting, Like you mean, like that human made their
art around pre existing claw marks in the walls and
made that part of the art.
Speaker 1 (23:06):
Yeah, yeah, Like I believe that's the case with some
of the art in France's Chauvet caves, where you have
depictions of cave bears, but also evidence of cave bears,
including claw marks. Now speaking of humans there, of course,
there's long been some mystery over exactly what sort of
relationships Theanderthals and Homo sapiens had with the cave bears.
(23:27):
I mean, we're humans. We can't help it. We find
out that we were alive at all during the same
time period, We're like, what about us? How do we
factor into this fascinating and majestic scenario? What were we doing?
And did we ride them? Did we ride them? Did
we worship them? Yeah? There was this much popularized idea
that early humans worshiped cave bears, and it does seem
(23:50):
like there's some potential evidence for this, but apparently this
has long been disputed and sort of largely pushed out
of the way. This would have been the basis for
fictional works like the novel clan of the Cave Bear.
But there's still various mysteries along these lines. You know,
they will never know one d percent what our ancient
ancient ancestors really thought about these creatures. And it's also
(24:13):
easy to simplify what we thought about them that like, oh,
did we worship them? Or did we eat them? Or
did we run from them? And of course, you know,
even our prehistoric ancestors I think would have had the
mental complexity to do all three, depending on where you
are in a given day and so forth, I.
Speaker 3 (24:32):
Seem to I think it's been years now, but I
have a memory of coming across some interesting claims on
the internet about about, like, you know, prehistoric humans and
their specific beliefs regarding bears, And I was like, what's
the source of this, Like what's the evidence for it?
And I could never actually track it down, Like it
seems like there's just a lot of claims floating around
(24:54):
on the internet about about prehistoric humans and bears.
Speaker 1 (24:58):
Yeah, I mean, I guess I one level, Well, it's
like we do acknowledge the fact that human ancient humans
and prestark humans, they acknowledged these large creatures in their
natural world. Yeah, they had relationships with various creatures in
their natural world, and they seem to have superstitious and
or mythological ideas about them. We talked about some of
(25:21):
the earliest images and past episodes of the show where
these people would combine human and animal imagery into a
single entity. Though exactly what is meant by that, we're
not sure.
Speaker 3 (25:34):
Yeah, this actually came up in a listener mail I
did while you were out recently. A listener wrote in
about our episode on the loewenmine, you know this carving
that has been interpreted as depicting a sort of a
human body with the lion's head, though there's some dispute
about whether that's the correct interpretation of what it's supposed
to be, but that seems like a common interpretation, and
(25:55):
so yeah, this raised these interesting questions about like when
did we start forming ideas about creatures that did not
exist in nature.
Speaker 1 (26:04):
Yeah, it is hard for us to figure out the
exact artistic content. For example, going back to the Chouve
Cave in France, this is a cave that contains human
illustrations of cave bears among other animals, copious amounts of
cave bear bones, cave bear claw marks on the walls,
it has floor depressions made by the bears. But one
(26:25):
chamber here also apparently has a single cave bear skull
that seemed to have been placed on a stone slab
in the center of the chamber. But it's impossible to
say why this is the case, like were they worshiping
the bear or a particular bear, was it just a curiosity,
was it some form of superstition or what did it
(26:47):
represent some like tangible connection between these people and their
way of life to the bear or was it something
more abstract. Now apparently we do know from some skeletal
evidence this would be in rare cases some evidence of butchery.
And also there may have been another example that was
more directly tied to some sort of like hunting weapon,
(27:09):
but at least butchery evidence that shows that humans at
least sometimes hunted or killed or at least butchered cave bears,
but is pointed out in Andrew Curry's twenty ten Fate
of the Cave Bear article ver Smithsonian dot Com, citing
anthropologist Eric Trinkhaus, it's unlikely that human hunting impacted the
(27:30):
cave bear's existence or led to its extinction. Trenkiles points
out faced many Illethal threats during this time, and the
cave bear, if provoked, was certainly one of them. I mean,
just because it doesn't really eat meat doesn't mean that
an animal this big and this ferocious could not kill you.
(27:50):
So it's unlikely, according to this expert, that humans tangled
with it all that much. But they might have sometimes
gone after hibernating bears or hunted them in other isolated
events for one reason or another. So it happened, but
probably not all that often. Still there's again there's a
(28:12):
lot of room for some level of supernatural consideration of
the cave bear. Going back to the work of a
wolf Storrel in his book, he writes that Shirley quote,
any animal that can go in and out of the
womb of the Great Goddess without incident is surely also
a guardian of fertility and birth. Again, he's predominantly an
anthropologist and athnobotanist. So this is the book in its entirety,
(28:36):
is more about how we have thought about bears throughout history,
even getting into at least short entries on ewoks and
Fozzy Bear later on. But particularly he points to other
traditions along these lines of a female bear shaman character
a lady of the caves, and also reflects on up
(28:57):
to traditions of the ancient Greek god is Artemis, whose
domain includes both the hunt and childbirth and is also
associated with bears. M interesting, but of course we just
get increasing way into the domain of speculation in this. Yeah. Again,
I think most experts kind of dismissed the notion that
that that early Homo sapiens worshiped the cave bear to
(29:22):
any significant degree.
Speaker 3 (29:24):
By dismissed, I assume you mean not that they rule
it out, but they just say, we don't have super
strong evidence.
Speaker 1 (29:30):
Yeah. Yeah, that's the That's that's what I get from it,
because I think it would be silly to say, you know,
our ancestors didn't notice these things at all, or they
didn't care about like it seems like there's there's room
for there to be that connection. But do we have
the evidence of it.
Speaker 3 (29:45):
Yeah, it's just one of those mysteries. There's a lot
about the culture of prehistoric humans that's difficult to know
based on the evidence we have.
Speaker 1 (29:52):
Yeah, real quick in passing before we move on to
more important matters, I will say that Storrel has one entry,
actually a whole page in the book on gummy bears,
also apparently known as dancing bears, which apparently have Germanic
origins going back to nineteen twenty two and are quote
now part of the German way of life. Okay, he
(30:14):
doesn't get into this issue in this twenty eighteen book,
but I wonder what he would make of the increasing
use of bear shaped gummies as a delivery system for
CBD and cannabis and cannabis related products. And even before this,
I think, going back in the nineties, they were being
used in some cases to deliver vitamins, and today you
can get all manner of supplements in them. So like
(30:35):
the dancing bear kind of becomes this shumnistic item. Perhaps
once more you know that's funny, but no real connection
to the cave bear there.
Speaker 3 (30:45):
Sorry, What would you make also about the equivalency of
worms there, and the fact that the gummy worms are
typically larger than the bears. That suggests something about Shai
lude to me.
Speaker 1 (30:54):
Ah, yes, solid point. For some reason, I've gotten to
the point where I accept a bear shaped gummy is
an appropriate shape for some sort of chemical delivery system
as opposed to some of the other shape Like for
some reason, a worm is too silly for me, Like
it just seems like, why, what what are you doing?
It's ridiculous. Responsible kids eat candy worms, but bears, bears?
(31:19):
I don't know, Like are we at the point where
I just you know, we don't. I guess we don't
go through a lot of gummy bears. But it just
it's just like I would be suspicious of a gummy bear.
I would be like, be careful, you don't know what's
in that bear. But a pure gummy worm, you're saying
you're more likely to trust that, I guess, But now
I'm second guessing myself. I don't know. I'm just suspicious
(31:39):
of the whole gummy genre.
Speaker 3 (31:51):
Okay, well, I've got one more thing I want to
talk about. So we've discussed the ways that animals adapt
to cave environments, but I wanted to talk about a
fascinating idea I came across in a spielology paper, which is,
what if some of the natural holes and recessions in
rock that we call caves were actually formed in part
(32:15):
not by standard inorganic processes like you know, lava tube
solidification in volcanic rock or the dissolution of limestone by
water instead were formed in part by animals essentially eating
their way through the rock. Let's look at a paper,
So my source here is by Charles A. Lundquist and
(32:37):
William W. Varnado Junior, called Salt Ingestion Caves, published in
the International Journal of Spielology in the year two thousand
and six. So the authors kick things off by pointing
out that, of course animals need salt to survive. It
is a basic requirement in the body. Regular table salt
(32:57):
is known chemically as sodium chloride, and when we ingest it,
our bodies use both the sodium ions and the chloride
ions from that molecule for a number of functions. Salt
is necessary for our muscles to function properly, like we
need sodium so muscles can contract and relax. It's used
(33:18):
in our nervous systems to conduct impulses. It's used for
all kinds of things throughout the body, and most humans
get way more of it than we need because we
add supplemental salt to our food for taste. But of
course wild animals don't have the kind of ready access
to supplemental salt that we do in the wild. Carnivores
can usually get the salt they need by eating the
(33:41):
flesh of other animals, which naturally contains a good bit
of it, but for herbivores getting enough salt can be difficult.
The sodium content of most terrestrial plants is quite low,
and since ancient times, humans have noticed that animals, especially herbivores,
sometimes gather at what are called salt licks, or more broadly,
(34:03):
mineral licks, places where there are rocks or soils that
animals can consume in some way to supplement the mineral
content of their diet, including minerals such as sodium salt.
This can include a range of behaviors in the wild,
like licking salty rocks on a mountainside, eating exposed clays
(34:25):
or other sediments that have a desirable mineral content. And
because herbivores are drawn to these salty rocks and soils,
hunters have long known about them as good places to
find game. So what does this have to do with caves? Well,
the author's rite quote large vertebrate herbivores, when they find
a salt bearing layer of rock in a cliff face,
(34:47):
can over generations produce sizeable voids where they have removed
and consumed salty rock. These cavities that humans can enter
can have the characteristics of a cave as defined locally.
So that last sentence meaning that, you know, whatever people
call a cave, You know that varies from place to place,
but usually it means like a void in the rock
(35:09):
that's large enough for a person to go into to enter.
And those types of voids can indeed be created by
animals removing the rock by eating it.
Speaker 1 (35:21):
Wow, So you're saying that in some cases a cave
is naturally formed over geologic time by rain, water and
so forth. Other times a deer just licks it until
it's right a deer licked it into the side of
a mountain.
Speaker 3 (35:34):
That appears to be the case, according to these authors.
So they look at several case studies in the paper.
One is a site referenced in some literature about the
Altai Mountains in Asia. The authors are talking about reports
from surveys of the Altai Mountains, specifically of a mountain
bearing shale formations near the confluence of the Kan River
(35:57):
and the Charch River. Apparently, the shale here is very salty,
and they quote a commentary by an author named Carl
Friedrich von Eltibor from eighteen twenty six, who writes of
the shale quote, all livestock of the Kalmuks find this rock,
which gives the mountain an ash gray appearance, very desirable,
(36:19):
and consume it in not small amounts, so that one
not infrequently finds grottos built in this way. Of course,
a grotto refers to a small cave, and this author
mentions that both domestic and wild animals come to this
mountain to eat the shale. Another example they mention is
a place in the United States. It's called rock House Cave.
(36:43):
It's a cave situated within the rock of a small
bluff in the US state of Mississippi. They say that
the entrance is roughly ten feet wide, but then the
cave actually widens once you go inside. It roughly doubles
in width. It's just about tall enough for an adult
to stand up, and it reaches about fifteen feet deep
into the bluff. And they say the surrounding rock is
(37:05):
mostly what the authors characterize as a soft, fine grained sandstone.
They say it is of the Kataboulah formation, and it's
got a significant amount of sodium chloride in it. The
authors also say there's no evidence that water solution caused
the formation of this cave, and instead it appears that
it was caused by many generations of animals removing the
(37:28):
walls by licking. They say there is a rough surface
on the walls that seems to quite possibly have been
created just by animals licking it away over time. They
say it was probably first wild deer and possibly bison
that opened this cave up, and then maybe cattle later.
Speaker 1 (37:44):
Oh wow.
Speaker 3 (37:45):
But the most amazing example they cite is one from
eastern Africa. This so, there's an extinct volcano on the
border between Kenya and Uganda. This volcano is called Mount
elgon or Elgonyi, and on the side of this mountain
there are what I've read described elsewhere as ballroom sized caves,
(38:08):
large sizable caves that appear to have been at least
in part excavated by elephants. Elephants inside caves, Yes, yes,
so there there is some question about the role of
the elephants in creating the caves, but there is no
question that the cave that the elephants do go into
the caves and consume rocks that has been directly observed.
(38:31):
That's the thing that happens. So the most famous of
the Mount Elgon caves is known as Katoomb Cave k
t u M and the authors propose that these caves
were formed in part by water solution, but also in
part because wild herbivores literally eat the rocks away and
remove them from the caverns.
Speaker 1 (38:52):
Yeah, this is this is amazing. I have I've actually
seen footage of this. I don't remember which elephant documentary
I saw this in Problem maybe More and One watched
a lot of elephant documentaries at one point, and my
son's upbringing when he was super into elephants. But it's
it is amazing to behold. And these are large caves,
you know, starters elephants have to fit in them. But yeah,
(39:15):
I think ballroom seems appropriate based on the footage as
I remember it, because these look like the kind of
caverns that you might have filmed like a B movie
in or perhaps an episode of Star Trek took place in. Yeah, yeah,
I can see that.
Speaker 3 (39:29):
Now elephants are not the only animals that go into
these caves to eat the to like consume parts of
the walls and eat the rocks. Apparently, also buffaloes, antelopes,
and sometimes monkeys have been observed to go into the
caves and eat some of the some of the soft
rocks that line the walls. The authors say specifically Katoomb
Cave to give you a better idea about the size
(39:51):
of one of the big caves. Here, they say that
the rock face that the elephants generally go to to
get to get their minerals from is about one hundred
and sixty meters into the mountain from the entrance, so
that's a deep cave. And they say that what happens
is the elephants go in and they usually loosen pieces
(40:12):
of rock from the walls of the cave with their tusks,
so they're like digging against the walls with their tusks.
These pieces fall to the floor, and then they pick
up the pieces with their trunks, and then they put
the piece in their mouth and chew it up crush
it with their teeth. Now, what was not fully resolved
at the time of this paper, and from what I
can tell, has still not been fully resolved, is what
(40:35):
are the relative contributions of the different processes to how
large the caves are like, are the caves predominantly formed
by inorganic solution and erosion of the rock by water
flow and then supplemented is that excavation supplemented by elephants
and other animals removing some amount of rock? Or are
(40:57):
the elephants and other animals primarily respectible for hollowing out
the caves and there's just some solution by water going on?
Also what role may have been played by like human
mining and other factors. So the authors look at several
analyzes of this, and they quote one researcher named Ian
Redmond who did a study of the cave in nineteen
(41:19):
eighty four. Redmond did several months of field observations, watching
the elephants and analyzing even the mineral content of their droppings.
Redmond wrote, quote, the volume of Katumb cave is on
the order of one point three million gallons or about
five million liders. If for the sake of conservative argument,
(41:40):
we suppose that elephant excavations averaged just one quart per week,
it would have taken only one hundred thousand years for
them to dig Katum. The theory of elephants, spieleogenesis cave
creation is entirely plausible. Wow, yeah, amazing to consider. The
authors also they cite another study, this one by researchers
(42:02):
named Donald McFarlane and Joyce Lundberg. This was from two
thousand and four where after field observations, these researchers suggested
a multi step process for cave formation that would go
like this. They summarize it as follows. So, first of all,
there is a cliff that forms. There's like water flowing
(42:23):
off of the mountain they say, off of a cap
rock layer, and it erodes some material from underneath. Then
after that they say that some more material clay sized
material sediment is removed from the floor of the cave
by groundwater sapping. And then they also say more mass
(42:43):
is removed from the cave by animal excavation. And then
at some point there are collapses within the cave. They write,
quote collapse of overlying beds makes piles of broken material
which are removed by action of water and animal geoff
rock eating. And then finally they say step four is repeat.
(43:05):
This whole process repeats over and over again. So they're
saying that it's a combination of material being removed by
water flow and then the cavern collapsing as material is
removed and supporting walls are removed, and then animals also
remove parts of the walls and remove some of the
collapsed material from above, and it just keeps going on.
Speaker 1 (43:27):
Like that because those animals, they don't care about the
structural integrity of the cave. They just want to get
that salt right. It's all they want is they're fix now.
Speaker 3 (43:36):
Ultimately, the authors of this analysis, McFarlane and Lundberg, were
unable to say what the relative masses of rock removed
by water versus geophagi were, but they seem to believe
that the amount removed by the animals was significant. And
then coming back to the parent paper, the one by
Lundquist and Varnido Junior, they bring up something that was
(43:58):
interesting when thought about. When I was thinking about it,
in parallel to our discussion of batguana, is a kind
of alternative sunlight or base of the food chain in
deeper limestone caves. Speaking of the Mount Elgun caves, the
authors here note that quote a common feature in most
of the larger caves is the quantity of dung deposited
(44:19):
by beasts which have come to the caves from time
immemorial to lick or otherwise consume the agglomerate walls. Traces
of elephants using the caves are most common, and their
tusk marks are clearly recognizable where they have gouged the rock.
So actually a couple interesting parallels there, the connection to
the seeing where the elephants with their tusks have like
(44:42):
cut gashes in the rock in the walls of the caves,
kind of like the marks on the cave walls left
by the cave bears. But also all the poop, all
the poop of all the visitors accumulating over the thousands
of years.
Speaker 1 (44:55):
Yeah, it's crazy, and you know all this also reminds
me of episode we did a while back on giant sloths,
a particular variety of giant sloth that would have dug
itself kind of a burrow into a like deep into burrow,
creating eventually over time as they reuse these spaces a
(45:16):
kind of tunnel in the earth.
Speaker 3 (45:18):
Funny you should mention that because the fourth case study
that the authors bring up in this paper is evidence
related to what's called Mylodon Cave in Patagonia in Chile.
They say that it is possible that this is a
case of cave formation by salt ingestion long ago, this
time implicating extinct giant ground sloths. This is fully speculative,
(45:41):
but they do highlight this as a possibility, explaining where
this cave came from.
Speaker 1 (45:45):
Wow.
Speaker 3 (45:46):
But to come back and conclude the look at the
Mount Elgon caves. So they say, what we do know
is that animals come to these caves to consume mineral
laden soil and rocks, so these caves could be thought
of as massive salt licks or mineral licks. There are
generally no permanent streams running out of the caves, so
that that's not an option for removal of cave material
(46:10):
by like permanent water passage. Some water does appear to
run out of the caves during flooding events, but how
much rock material is removed during these events in this
way is uncertain, so we still in the end don't
know the relative amounts. We don't know how much of
the cave formation is due to water solution versus how
(46:34):
much is due to animals eating the rock. But they
think that both processes contribute, and their judgment in the
end is that the contribution of the elephants is the
primary process.
Speaker 1 (46:47):
Wow.
Speaker 3 (46:47):
Either way, it's amazing to imagine elephants going into caves
to eat the rocks.
Speaker 1 (46:52):
Yeah, it's amazing. And you know, we shouldn't cast too
much judgment. Like you mentioned earlier, humans very often don't
have to worry about getting enough salt we eat at
a restaurant. Once we get like a colossal salt bomb, right,
we get we get more than enough salt. We get
an unhealthy amount of salt ingested into our bodies. But
(47:14):
if we didn't have those food sources, we might be
out there looking the sides of mountains just like these
various herbivores are. Assuming we also didn't eat copious amounts
of meat on top of that, which is another factor
to consider here.
Speaker 3 (47:30):
Yeah, all right, well does that do it for this
exploration of caves. I'm sure we'll be back in the future.
Speaker 1 (47:36):
Yeah, there's all I mean, we've we've covered caves in
the past. Yeah, we'll be back in the future. And
there are a number of fascinating cave organisms that we
didn't cover in these episodes. And if you have favorites
right in, we'd love to hear from you, because we
could always venture back into the caves. You know, we
don't reside there all the time, but we we go
in from time to time in order to discuss something interesting.
(47:58):
All right, as as usual, we'll just remind you that
Stuff to Blow Your Mind is primarily a science and
culture podcast, with core episodes on Tuesdays and Thursdays, listener
mail on Mondays, short form episode on Wednesdays, and on Fridays.
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(48:21):
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(49:03):
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Speaker 3 (49:05):
Huge thanks as always to our excellent audio producer JJ Posway.
If you would like to get in touch with us
with feedback on this episode or any other, to suggest
a topic for the future, or just to say hello,
you can email us at contact at stuff to Blow
your Mind dot com.
Speaker 2 (49:27):
Stuff to Blow Your Mind is production of iHeartRadio. For
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