The size of a black bear, this Ice Age giant didn't build dams, but it guarded the water with a fearsome call just the same. Meet the world's most complete fossil giant beaver with Heather Lerner, the ancient DNA expert who brought her to life!

Get three extinct animals raised to life as monsters in D&D: https://www.scintilla.studio/extinction

Episode transcript: https://scintilla.studio/monster-extinction-giant-beaver/

Guides:

Dr. Heather Lerner, Curator of the Joseph Moore Museum

https://twitter.com/moore_museum

Join the conversation: www.twitter.com/SparkOtter

"Extinction Theme" by Alexandre Miller, The Boy King of Idaho

This is the tooth.

That's the tooth?!?

That is one tooth.

Yep.

This is the left encisor.

It is the size of a banana

Big banana.

You're looking at this and thinking

with the size of teeth like that, I

could take down some big trees.

Right?

Are you thinking that?

I am well, I am now.

Okay.

Well, you shouldn't be

thinking that cuz that's wrong.

I was mean right?

Ah,

here she is.

Wait,

What?

Ah!

This one right here?

I love this orientation.

She is coming right at you.

Welcome to Making a Monster:

Extinction, investigating the stories

of vanished species as we gather

them into a bestiary for 5th edition

Dungeons & Dragons called Book of

Extinction, coming to Kickstarter

in March of 2023 and previewing

now on the Mage Hand Press Patreon.

This is the sound of GenCon, where I spent

this last weekend sharing the book with

gamers and makers from all over the world.

But tucked away not too far from

the biggest 4 days in gaming is a

surprising gem of natural history.

Welcome to Richmond,

Indiana podcast listener.

I'm here on the trail of an ice age giant.

We're at the Joseph Moore

Museum at Earlham College.

Prehistoric megafauna are an integral

part of the fantasy genre, giant monsters

who awaken the kind of fear humans

only feel in the presence of an apex

predator more powerful than themselves.

This week I want to introduce you to

one of the most unexpectedly fascinating

creatures among that pantheon of ice

age beasts and her fascinating journey

through near time alongside an Egyptian

mummy, a mastodon, and maybe the most

dedicated graduate students in history.

Our guide on this journey

is Doctor Heather Lerner.

So I'm Heather Lerner.

I'm the director of the Joseph

Moore Museum, which is a regional

natural history museum at Earlham

College; also an associate professor

of biology and museum studies.

I was recruited from the Smithsonian

where I was working in ancient DNA.

And I came out here for an interview and

got to go into the museum and see the

world's most complete fossil giant beaver.

And I will confess at that

moment, I was, let's see, eight

months pregnant with twins.

And I thought the giant beaver

was pretty cool, but I mostly

identified with the giant ground

sloth , which, um, was not exactly

the reaction they were looking for.

Heather gave me an inside

tour of the Joseph Moore Museum,

including a lot of stuff the

general public doesn't get to see.

And in the interest of better

understanding the ancient megafauna in

Book of Extinction, Heather will introduce

us to the giant beaver in the order in

which a scientist of her caliber would

- starting with today and working backward

The giant beaver

is just an incredible creature.

And from the first moment that

I knew about it in my interview

here, I thought, "I know how to

get DNA out of really old things.

And I would love the challenge

of trying to sequence DNA from

the extinct giant beaver and see

what we could learn from that."

So I started there and then

started thinking, well, what,

why would that be useful?

Just cuz you can do something

doesn't mean you should do something,

which I have to tell my children.

just cuz you can doesn't mean you should.

Um, so I spent a while really

learning about beavers.

so we know there are two

species today of modern beavers.

There's the North American and the

Eurasian, they're closely related

to each other and to nothing

else , which makes it very hard to

figure out things about their past.

Why do they look the way they do?

Why do they do the things they do?

If we don't have that evolutionary

record, it just really hinders the

explanations that we can come up with.

So, um, one of the things you can do

to try to figure out close relatives

is to add in extinct species.

And it turns out that what beavers

are closely related to are a lot

of other extinct species , um,

which includes the giant beaver.

And the giant beaver is pretty cool

because it's part of the group of beavers

that you would be more familiar with in

terms of living an aquatic lifestyle.

That's what you think of when

you think of beavers, right?

Ponds, streams, that kind of thing.

Yeah.

Um, it turns out this is super cool.

There's a whole group of extinct

beavers that are called fossorial

or upland digging beavers.

Right.

Who knew?

It turns out people

who study fossils know.

So, um, there are maybe seven to

twelve genera of extinct fossorial,

terrestrial, upland, burrowing, beavers.

And they go back far enough in

time that we are not probably

gonna get DNA out of them.

so figuring out those relationships

is probably in terms of using

DNA, a loss cause, but Casteroides

ohioensis the giant beaver.

Was around until not that long ago.

So maybe 10,000 years ago.

And that is a tractable question

using ancient DNA techniques.

That's a timeline in which

things are preserved well

enough that you can get DNA.

So we set about trying to sequence

the giant beaver to help us figure

out those relationships in particular,

when did beavers become aquatic?

Since we know there's this whole Upland

group, when did this thing that we

associate with beavers become true.

So you can use lots of clues, like, um,

their body shape from the extinct species

and sort of piece things together there.

But unless, you know, when those

species really lived, it can be hard

to get that timeline of evolution.

So using DNA, we can really anchor

that those trait evolutions in time.

So that's what we did.

We sequenced the mitochondrial genome,

um, of the extinct beaver and,

um, we're able to figure this out.

I just want, I just wanna

pause on how cool that sentence is.

That's an incredible amount of work.

It was

years in the making.

Yeah, so first we spent a year building

an ancient DNA lab here, which meant

all the physical labor of cleaning

out an entire room and taking every,

everything out of there all like

demolition work, plus painting everything

and, uh, trying to get it to be a

safe place to look at ancient DNA.

Because it turns out that we

are shedding DNA all the time.

as we walk around, we are just

discarding our DNA everywhere.

So if you wanna work on old things that

don't have a lot of their own DNA, you

don't wanna be adding your DNA to the mix.

I did not wanna sequence myself.

We wanted to sequence giant beaver.

So we needed that ancient DNA room.

So we spent a year doing

that, got that done.

And then we were gonna start the process

of taking the fossils, using a drummer

and drilling out the hardest pieces of the

fossils, which would be the pieces that

had the most resistance to degradation.

So they might have the best DNA in there.

Most intact.

We wanted to start that process and

there was a two week power outage.

We only had three weeks set to be together

to work on the project for that summer.

And that was two thirds of our.

Wow.

So we didn't do it that year we

ended up working on raptors instead,

which was a great fun project.

Um, but it did delay us a couple of

years to be able to, to be able to do

that process but it gave us time to

learn more about beavers because it

turns out there's lots to know which

I'm very excited that you want to

know all about beavers you do, right?

I do.

Yeah.

Okay, good.

That's what I'm here for.

That's great.

we're gonna have a great time.

So I'm gonna take you

into the collections.

We'll start with the modern beaver

just to kind of orient you and then

we'll take some of those things

with us and go find the fossils.

Perfect.

Okay.

Let's do it.

Great!

So the room

we're in is the mammal division.

Um, and we have, oh, maybe five

or 6,000 mammal specimens in here.

Right.

It doesn't, you just look like that.

Right.

. Yeah.

And that's because the way that we

prepare them is to, um, we remove

all the insides and then we keep the

skins preserved and then we put the

fossil or the skeletons in a box.

So it's all very tight and compact.

Yeah.

You, when you're thinking of museums are

thinking of taxidermy, which is posed

animals, so that they look lifelike

and that's an art form, and that is

amazing and important, but I can't

fit a lot of those posed puffed up

animals in this room, this size, right?

So we, we have study skins and there

are, you know, depending on the

size of the animal, there can be

a hundred of 'em on a single tray.

So we are gonna go look for

Castor canadensis which is

the modern beaver, right.

So that you can see it and touch it.

Yes.

Okay.

I get to touch stuff.

Okay.

Whoa.

We're gonna take

this out and put it over here.

Okay.

So this is a tray that has

a modern beaver pelt on it.

So it's just kind of folded

up like a little blanket.

Um, and you can see the tail here

on top can see that leather really

tail . Yes, we are excited about the

giant beaver, but it turns out modern

beavers are fairly big themselves.

Big . So what I want you to notice,

because you did wash your hands,

so I'm gonna allow you to touch it.

Thank you.

You can feel that

fur, what do you think of the fur?

Oh man.

Nowhere in my life, have I ever laid a

hand on mink, but I know that aquatic

animals have a hugely different

fur to, uh, to terrestrial animals.

Exactly.

Um, so we've got two different

lengths and textures here.

Already, um, kind a

Got that

guard fur on the outside,

. Lucas: And then a softer, it's so plush

underneath , I'm getting chills cuz

that's the kind of weirdo that I am like.

And I think you can

really identify with the people who

were trapping and selling beaver pelts.

This is incredibly warm, resilient, fur.

This is gonna get you through a winter

and winters were harsh, and we didn't

have access to all sorts of materials to

keep warm and protected from the elements.

It was a major concern.

And so just feeling this, I think you can

understand why they were so desirable,

but also just with them being so

desirable, why beavers faced such threats.

Um, so I wanted you to feel that.

The other thing I wanted to show you

is something that I learned when we

spent all this extra time learning

about beavers before sequencing.

They do have this amazing thing

and it's on their hind feet.

Um, and it's this adaptation

to two of their toes.

Um, and so this first toe here,

so there's this fleshy pad and

then there's this, this nail.

And what happens is when they, when

they bend their, their paw like this,

they trap their fur in between there.

And it's a comb and they do

that with this one as well.

And it's not as easily.

No, here it is.

Is that it?

Here it is.

Okay.

It's this one that has the

big fleshy pad and the claw.

And so it can squeeze that.

So it's that the claw is the

same, uh, or rather the opposite,

um, concave shape to the pads.

Convex.

Yeah.

So they nest within each other.

If you like, take your pointer finger

from each hand and sort of make a

little arc and attach them to each

other and you can squeeze between that.

Right.

Right.

And as they bend their, um, they flex that

squeezes, the pad against the, against the

nail your pad is attached to your nail.

You're not gonna run something between

your pad and your nail on your finger.

Huh.

Right.

Like you're not gonna, I mean, you

might run your fingers through your

hair but imagine if you could flex

down and actually turn that into a

tight comb, that's what they're doing.

Amazing.

And they do that with both of those toes.

So that one that has the fleshy

pad and the nail, and then this

one that has like a split nail.

So there's a hard piece

here and a hard piece there.

And, and, you know, That's

gonna do different things.

It's like two different types of comb

that they have so they can spread

oil and they can remove debris and

clean themselves, essentially with this

little tool that's on their hind feet.

In terms of, I guess, yardage,

if we're thinking about textiles.

Hmm.

Um, how much would you get from one?

That's a good question.

A little more than a

yard and it's doubled over.

So I'd say about a yard of fabric.

Yeah.

Amazing from just that one individual.

And this does look like an adult.

It is, it was a good

size and it was a male.

its weight was 57 pounds, 12 ounces.

Its total length was 46 and a half inches.

So that's pretty long.

Wow.

Yeah.

So we record information about the

animals when we collect them as much as

we possibly can, because like I said,

you can't go back and get that later.

So any information we have about the

habitat, it was in the things, it was

doing photographs, video recordings,

um, measurements, anything we can

get, we will keep with the animals

so that we have the most information.

So then there's a

digital record that's attached

to this particular specimen.

Incredible.

And like I said, we, in

addition to having the skin that you've

just been looking at or the pelt, um, we

also try to keep, um, the skeleton and so

this box has the skull for this one in it.

Oh

wow.

I wasn't ready for this.

So you can.

Re-articulate the jaws there.

And then you can see the, see that skull.

Amazing.

So that's a chomping.

Yeah.

And you can see the teeth here,

have this orange across them in the

front , um, that's probably related

to some iron deposit there and that's

common in rodents, um, to have that.

And that gives it real firm firmness to

the teeth that even our teeth don't have.

We have enamel, but we don't have

that particular hard structure.

Um, and that is so it's taking

iron from its environment and it's,

it's sequestering it

there yeah, we, we keep the iron in

our blood and they probably have iron in

their blood too, of course, being mammals.

But, um, they must be depositing

some of their teeth too.

That's incredible.

They have metal teeth, you're telling me?

Yeah, basically.

Yeah.

That's a good way of thinking of it.

Yes, that is correct.

yeah.

And that really, um, provides that

strength that they need for all

of the chewing that they would do.

Um, So I'm gonna put this back and we're

actually gonna take one of these skulls

with us and go find the skulls that

we have of the extinct giant beavers.

So you can see those right together

and we will eventually make it to the

world's most complete fossil giant beaver.

Let me paint another picture

here because we, this looks like

somebody's garage, but a garage that

they would've spent a lot of time in

and there are long, low tables in it.

And, uh, more of the filing

cabinets around the walls.

I'll also state for the record.

One of these cabinets is

labeled dinosaur bones.

yes.

You know, I need a career change.

six year old me would've

been losing his mind.

This entire cabinet

is dedicated to our giant beaver

to the most complete, and this

holds a copy of every bone in it.

So these are,

It's the best jigsaw puzzle!

It is.

It's actually really fun to put together.

Done that a few times.

Um, so this is the first

copy that we ever made.

Um, and it is made from creating

molds of each individual bone.

Um, except for the feet

we did those all together.

So many little bones in a foot, right?

And if you go find a giant beaver in

another museum, it's potentially a copy of

ours because we cast it in the 1980s, and

then many museums got copies from that.

Right.

And then we also created a new copy

of it a few years ago with the help of

two researchers who were then at the

Virginia Museum of Natural History who

came here and we made all new molds

because molds deteriorate over time.

And so do copies, um, and

some things had changed.

We needed to modify the skull a little

bit because it had been built up.

On our original, some clay had been added

and we needed to change that because

after finding more skulls, we knew

that some of the sutures were wrong.

Okay.

So in your skull, you have different bones

that come together to form that, right?

And they fuse together as

you grow and stop growing.

Once you stop growing, they fuse together.

So those lines we guessed

at based on modern beavers.

And it turns out when we found war

fossil skulls, we needed to change

that because they were not correct.

So this entire cabinet here is a copy

and I'm gonna look, it

would've been plaster of Paris.

Uh,

yeah, probably.

Yeah.

And now we're working in,

in silicone or, or 3d,

We've

done two different things.

One is that we are using silicone

molds, um, and then casting in resin.

Um, the other thing is that, so if you

come and play our giant beaver escape

game, which I know you would love, um,

you actually get to handle some of the

copies and those copies used to be cast,

which are very good for research, right?

They are very high quality,

scientifically accurate.

The kind of thing I will study off of

rather than bother the specimen itself.

And one of those disappeared.

So just a few weeks ago, we 3d,

scanned and printed copies because

now we can always reprint, but

the molds deteriorate over time.

And in fact, we don't have the molds

here, so I can't just make a backup copy.

Now that that one piece is gone.

Huh?

I'm gonna get into this cabinet here.

And I should be able to show you

the one that we actually sequence.

So in here you'll see

that we sampled for DNA.

whoa.

So anytime we

do something, we put a note in.

So round plug, meaning that

you drilled a very, very small, uh,

almost like a core sample.

Exactly.

So, so

then you would have a

tiny rod of, uh, fossil material.

, uh, not just like drilling it out and then

sort of taking the fossil saw dust, but

rather a

whole take the actual plug.

We do grind it up then, but we do

take the plug . And one of the reasons

you're trying to do that plug is that

you wanna get past the really hard

enamel on the outside of the teeth

into the soft protected material

where the DNA should be preserved.

And what's very cool about teeth is

that it's one of the few places in your

body that you retain pluripotent cells.

So cells that can become anything.

Cells that are very open to suggestion.

They generally don't do anything else, but

you know, whatever they do in your teeth.

Um, but if you need cells that are

activate-able, that's a place to get them.

And what that does mean is that

they are less, um, less bound up.

And so that DNA can be super good.

And it means that there's

a lot of DNA in there.

So that's why we're aiming for teeth.

This I believe is the one that we got

DNA out of, which is somewhat surprising.

You see, we sampled it on the

14th of May, 2015, Micha Ahmed and

Jacob Paris and me, they get their

names written out and I'm just HRL.

So that's the one that we got,

uh, two thirds of the genome

from, the mitochondrial genome.

Yeah.

And actually this is the ulna,

the tooth did not end up working.

Okay.

And what what's interesting about

that is we did a lot of work trying to

figure out exactly where we would have

the most, the highest likelihood of,

um, getting DNA and what turned out

to happen is that wasn't so useful?

The most important thing was it

was collected more recently, which

meant that it had had less time out

of its deposition environment to

accumulate damage or to deteriorate.

So like I said, we're trying to keep

things so that stable temperature

and humidity, because when you have

fluctuations is when DNA gets damaged.

Well, we don't really have stable,

uh, temperature and humidity here.

And so over time, things just deteriorate.

Um, so one of the things we're

really actively working on trying

to improve conditions so that

things will be useful for longer.

So the most recently collected specimen

is the one that worked , but I know

an awful lot about DNA preservation.

So let's take this one over.

This is the tooth.

That's the tooth?!?

That is one tooth.

Yep.

This is the left encisor.

It is the size of a banana

Big banana.

Thin, but very long.

Yeah.

Okay.

So let's just do this for a second.

We want you to see the

modern beaver, right.

You remember with the

little chompers, right?

Okay.

And then let's put that

next to the giant beaver.

This skull came from a four foot

50 pound beaver, and yet it is, um, the

size of two clenched fists, I would say.

Well, it

fits in my outstretched hand.

Right?

you know, the base of the skull

is at the base of your Palm and the tip

of the nose is at your index finger.

Yeah.

And then this one.

Like we don't

watch it like a football here.

You're looking at this and thinking

with the size of teeth like that, I

could take down some big trees.

Right?

Are you thinking that?

I am well, I am now.

Okay.

Well, you shouldn't be

thinking that cuz that's wrong.

I was mean right?

This is, it was, it was exactly.

Okay.

So what's really interesting about

this, um, is that they probably

didn't have that, um, same.

They didn't have that

same tooth structure.

They probably were not able

to chew off pieces of wood.

They were not chopping down trees.

We have two lines of evidence that tell

us this oh three, maybe number one.

We have not found any pieces of

wood, fossilized wood, with the

marks of giant beaver teeth on them.

That's, you know, absence of evidence

is not, right, evidence of absence.

Sure.

So we're gonna hold off on that,

but we haven't found that, um, we

haven't found any big dams or lodges

in context with a giant beaver.

Okay.

So that's more absence of evidence.

Um, the other thing is that you can,

like I said, these organisms hold

a signature of their environment.

You can look and see

what they were eating.

I could figure out what you are eating

from the stable isotopes in your hair.

Okay.

That was significantly less creepy

than I thought it was going to be,

talked about plugs drilled from teeth.

I'm not, I'm not

gonna take a plug of your teeth.

that's Nope.

I'm really far more interested in

the fossils, but if we wanted to

and people have done this, they have

looked at the signature of the foods

people are eating from their hair and

fingernails and you can see where like

what your favorite fast food is because

different fast food places are getting

their beef from different places.

Wow.

And that holds the

signature of the environment, the food,

it was eating the place it was living.

You literally are what you eat.

Yes, you are.

that?

Yeah, that is correct.

So, um, there was a really neat study

that came out in 20, 20 same year as

our, um, as our DNA study and they

were looking at a different species of

beaver, not so giant about two-thirds

the size of the modern beaver.

And that's a Dipoides, is the genus.

And they were curious, what

was this, this animal eating?

And then they were comparing it to

Casteroides, to our extinct giant

beaver and to Castor the modern beaver.

What they're doing is trying to figure

out, um, there are different options for

what these species could be eating, right?

You're in an aquatic environment.

And we have evidence that Dipoides

was in an aquatic environment.

It, um, evidence of,

uh, chewed, chewed wood.

So that's pretty strong, right?

Find Dipoides, you find some things

that look like maybe it was a lodge?

They could be eating bark, they could be

eating, you know, the, the layer right

underneath the bark, the stuff that has

good nutrients in it could be eating that.

So they could have been eating any

of the other plants that around them.

We know that they're vegetarian or

we assume they are given rodents,

um, long evolutionary history of

being vegetarian, um, or herbivores.

So they could have been eating

mosses and lichens and other things

that would be in this Tundra area

where the species was found, they

could be eating trees or shrubs.

They could also be eating

the, like the leafy vegetation

that would be in the ponds.

Right.

So macrophytes, that green fleshy stuff.

And so you can look at the

carbon and nitrogen isotopes in

those different types of plants.

And then you can look at the tissues of

that animal and see how they compare.

And there's a lot of other

science going on behind there.

Right?

You don't just lay down exactly

what you're eating your body,

modifies it a little bit.

And so you have to do some corrections

and things, but from this, they

were able to show that it does look

like Dipoides, I know we're taking a

detour here to a different species,

but it is important and relevant.

You can cut it if you need

to , but it looks like that one

was basically a generalist in the

sense that yes, it could do some

woody plants and those macrophytes.

Pretty cool.

Yeah.

They were also using information

from Casteroides and this is

where it gets really interesting.

doesn't look like they

were eating woody things.

Their signature shows much more

strongly in the macrophyte.

So then you start looking at those

teeth again and thinking, okay,

so not having the super strong

orange piece on those teeth, maybe

they really weren't doing that.

Maybe they weren't cutting down trees.

Maybe that absence of evidence is

because they're, they weren't doing it.

So start looking at those teeth again,

when you see this, um, the front teeth

have this sort of, um, inverted V shape

or like a little, little mountain shape

and where they, the two teeth meet is

almost like if you're gonna cut a piece

of paper and you just open the scissors

a little bit and sort of push it at

the paper and slice that paper apart.

Like this is a good slicing thing.

And you think about reeds,

you think about grasses?

You wanna cut those?

You just slice right through it

with this kind of a tooth structure.

Cool.

Right.

So rather than having a

metal knife in its mouth, it

has, uh, a pair of bone scissors.

Yeah.

Amazing.

it also has these wonderful molars and

those look like nice grinding teeth.

They're not in my opinion, that

dissimilar from the modern beaver.

Um, but modern beavers are

also gonna be eating that,

um, fleshy vegetation as well.

So in the summer, when you can

get it, you wanna eat stuff that

has the highest reward value.

So the most nutrients and,

you know, we need fiber.

Everybody needs fiber, but you

don't want it all to be fiber.

Like you don't wanna go heavily on the

tree side, if you don't have to really go

for the fleshy stuff, if you can get it.

So they're eating the fleshy plants,

but then they're caching those

twigs underwater to keep them cool.

And to last over the winter.

And that's why we have beavers

today is that they have that

adaptation of being able to make

it through those long dark winters.

And when they create those dams and

they create bigger bodies of water,

those bodies of water don't fully

freeze over so they can maintain an

open access underneath the water.

It can hide their food down

there, cause all the green plants

they're, they're not edible.

They're not growing in the winter.

They're covered in snow.

But if you can keep 'em in your

underwater refrigerator, all winter.

You can survive because

they don't really hibernate.

They kinda slow down, but they do

need to eat throughout the winter.

It's kind of a bummer that the giant

beaver doesn't seem to have been

using trees and building dams and

lodges because that probably is a

major contributor to its demise.

It wasn't able to handle

the warming of the climate.

It wasn't able to handle the

drying out of the climate.

It needed those big waterways,

you know, the, you find a lot

more Casteroides in the areas

south and around the great lakes.

So they just, they weren't able to

make it through that changing climate.

And so they did become extinct.

The end of the Pleistocene.

There's another really cool adaptation,

but I think we should go see the

most complete fossil giant fever.

Okay.

Let's do it.

We weren't in the museum?

We were behind the

scenes now we can go to the public side.

Let's go over here.

Pass the whooping crane pass.

Oh,

I'm gonna say it.

Uh, the, the, the most

complete skeleton of a fo-, shoot.

Yep.

World's most complete fossil giant beaver.

World's most complete

fossil giant beaver.

I got it.

You got it.

I think,

it is really nice to say,

ah,

here she is.

Wait,

what?

. Ah,

This one right here.

I love this orientation.

She is coming right at you.

Oh, she?

Yep.

We can tell from her pelvis

and her size that she's a she.

So when I first got here, she was turned

sideways and you could just see her from

the side, which you haven't even seen yet.

Yep.

And then we were doing some, you know,

renovations, new exhibit kind of stuff.

This whole exhibit is all new

signage, um, designed by our students.

Um, and we rotated her.

And for the first time we saw her

coming at us and we said, "Oh, that's

the way you need to approach her.

You need to think about a giant

beaver approaching you, or you

approaching a giant beaver."

Yes.

And there she is.

This is her.

This is her.

Yep.

This is not a copy.

In fact, we don't have an assembled copy.

I showed you that cabinet again, it's

all in different boxes so that we can

get them out and lay them out and, and

measure different things and look at them.

Right.

Like I said, taxidermy, not

so great for scientific study.

Also mounted, specimens, not

so great for scientific study.

It's a little hard to see every

single piece and rotate it and measure

all the things you wanna measure.

We have done it, you know, for

the Mastodon, we did measure all

the different parts so that we

could determine the size of it.

Question is scale.

I, uh, yes.

Lifting up that femur a little different,

but, um, so we actually have her on

exhibit in most places you will not see.

Well, I mean, nowhere else will you see.

The world's most complete, complete

fossil giant beaver , but we do

have her right here on exhibit.

Incredible.

You made a comment

before about seeing the skull of

an animal and thinking, gosh, it

seems bigger when I see it alive.

And if you think about it, very few

people are just the size of their bones.

In fact, no one is except a skeleton.

You have all sorts of muscles and

tendons and cartilage and fluid

and a whole layer of fat and skin

all over the top of those bones.

So just that alone is gonna add, you know,

depending on the particular organism,

half inch to an inch all the way around.

So it's really much bigger when

this animal was fleshed out and we

have some great illustrations, um,

Corbin Rainbolt was a student here

and he is a renowned paleo artist.

Um, and he did the artwork for our,

for this exhibit when he was a student.

And he has also continued to work with

us afterward and done drawings for us

because lots of times I need something

that shows the difference between

a modern and an extinct organism.

And so I, I need them in

context with each other.

I need a particular orientation and,

and Corbin does that kind of work.

In fact, what I'm wearing is

. . . Lucas: Hey!

A giant beaver mini skirt.

She's been here the whole time!

Yep.

Pretty cool.

That is fabulous, Heather!

And you can

get your own on red bubble.

You can also get a t-shirt and

other thing, a notebook or whatever.

exactly you day before.

I dunno.

You may have to buy a

couple different sizes.

So this is the world's most

complete fossil giant beaver.

It is not however, the type specimen.

I got it wrong.

I thought that's what it was.

It's not.

The type specimen is

no longer in existence.

It was lost in a fire.

And this one was also

almost lost in a fire.

So these are all these stories

are all wrapped up together.

um, she was found by some

farmers in the Eastern part

of Randolph county in Indiana.

They were opening up a ditch

to drain a swampy area.

It was locally known as "The Dismal."

And the contractor who was doing

this work came upon the skeleton.

And this is neat.

It said, "On account of its standing in

its natural position and its wonderful

tusks, it awakened a desire to save

all the parts that might be found."

That was written by Joseph Moore in

1890 when he described this specimen.

This contractor found this animal

and thought this doesn't look

like anything I've seen before.

look at those giant chompers, right?

Yeah.

And they wanted to know what it was.

They brought the skull into town,

the farmer whose property, it was

brought it into town and started asking

around and nobody knew what it was.

No one had seen anything

just like this before.

And you remember that giant

football in my arm for that skull.

If you found that you would be

wondering what the heck as well.

So no one knew what it was.

Somebody said, put it up

in the window of the bank.

Someone coming in or out will surely know.

So they put it up in

the window of the bank.

No one knew.

Finally someone said, take

it down to Earlham college.

If anyone will know it'll be Joseph Moore.

So they brought it down to

him and he immediately said,

"Well, I am not totally sure.

However, I do believe it's a giant beaver.

But the giant beaver has been described

from a fragment of tooth and jaw.

That's all that's ever

been found of it before.

And you have a whole skull school.

Is there anymore?"

And they said, "Oh yes, the

whole thing, it's right there!"

So they went back.

The contractor knew exactly where it was.

They dug the entire thing up.

It is seven eighths

complete, as I've said.

And so you can look at her and you can

see a slightly different coloration.

where you can see what's real.

And then that darker color, right, that

other matrix that we use to fill in the

parts that we're missing so that you have

what looks like a full skeleton here.

But very little of that

is that dark color, right?

There are a few of the

vertebra and the neck there.

Um, there's a little bit of the,

of the shoulder blade, um, a little

bit in the toes, but for the most

part, this is a complete skeleton.

So she, Joseph Moore purchased her

with some of his own money, some money

that was donated and brought her here

and she's remained here ever since.

Like I said, two different sets of

molds have been made from her so

that she can be shared throughout

the world and be studied more easily.

Um, but we did almost lose her in 1924.

Um, she was in Lindley hall, which was

where the museum was housed at the time.

And that night, um, just after

I wanna say midnight, um, the

building went up in flames.

The floors were wood and

they had just been oiled.

And so it went up hot and fast.

Students were awoken by the sounds

of this and ran out of their dorms.

Students worked in the museum

then just as they do today.

And they knew the incredible

value of this giant beaver.

And they ran into the burning building,

picked her up and carried her out.

We have a, a copy of a letter written by

one of those students after spending hours

doing this, went back to his dorm room and

sat down and wrote home to his mommy and

poppy to tell them about what happened.

And to say, I just, I don't

think I can settle down to sleep.

I don't know what the rest

of the semester's gonna be

look like, gonna look like.

This building burned.

This building also housed the

registrar and all the records.

A lot of the work was really saving

the, the specimens of the museum.

So we do, we are the caretakers

for an Egyptian woman, um,

Ta'an, she's, um, she's mummified

and she is in the museum here.

She was rescued.

The giant beaver was rescued

and you know, anything else

they could get their hands on.

In 1952, Jim cope, reestablished this

museum in the space that we have here.

And she was put back on display.

So there was about 25 years when

she was off exhibit, um, or at least

not in the Joseph Moore museum.

Right.

So she's back on display.

Wow, incredible.

So our students now know

the most important specimens that we have

and the order that you would save them.

they also know.

To be very careful with their own

selves and do not die in a fire.

that fire, the 1924 Linley fire did claim

the life of at least one firefighter.

And, um, it was deemed to be arson.

There are several hypotheses.

One was a disgruntled janitor who had

been fired, who would've known the

schedule of the oiling of the floors.

And would've known the best time

to take the whole building down.

Um, another hypothesis, since

all the registrar records were

burned, was that it was a student

hoping to erase their record.

And we don't know to this day, who did it.

Wow.

I wish someone's diary with a

confession would be found, right?

Yeah.

That is an incredible story.

Part of the reason that I knew I had

to come up here was I'm writing a

book for fantasy authors, essentially.

And to tell them that, Hey, there

was an Egyptian woman and a giant

beaver who survived a fire in

Indiana in the fifties like that

is, uh, you can't write this stuff.

She, she has some

pretty incredible history and some

real, real champions who would

risk their own lives to save her.

So you were asking what

a type specimen is.

Yeah.

And when I referenced how Joseph

Moore said, "Well, I think this is

a giant beaver, but the description

of giant beaver is based off of

the fragment of a tooth and a jaw."

That's it.

He then turned around and wrote a

paper that described this specimen,

but he could not name it because it

had already been named as Casteroides

ohioensis from that tiny little bit.

Wow.

So Joseph Moore

has an amazing paper that is really

descriptive about this entire skeleton,

but it is not the type specimen.

Type specimen is,

the individual for

which the species is described from.

We define this species to be something

that has these particular morphological.

Which are based on a tooth and a jaw.

What's very interesting is the

extraordinary bias in museum collections,

which mirrors the collecting tradition

that museums are built upon, which

is the collecting tradition of white

men going and documenting the world

around them and primarily collecting

male individuals of species and

describing species based on the males.

So the vast majority of

type specimens are males.

The vast majority of specimens

and collections are also males.

And that holds true even for species

and you might be thinking, okay,

well the males have bigger tusks.

They've got antlers.

They're very pretty, they're flashy.

Right?

We're gonna collect them.

They're also the ones that

may be more aggressive.

So they may be more easy to catch

because they might approach you

and you might be able to shoot

them or catch them or whatever.

Even controlling for that.

We do not collect in equal

numbers, males and females

what I think is really important

is to be able to describe the

variation within a species.

And when you boil it all down to the

type, the one, the original you miss

what makes up the beauty of species,

which is the unique traits, the range

from light brown to dark brown that

you see in the pelts, from the length

of the fur, from the lengths of the

tails, from the behavior, there's so

much beauty and, um, flavor that when

you focus on a type specimen, you lose.

What you didn't know about that I

said I was gonna tell you before,

and then I didn't is a very

cool feature of the giant beaver.

You're giving me the eyebrows.

And from what we talked about

before that didn't get eyebrows.

I know this is gonna be cool.

You look

inside of the modern beaver

and you can see the brain case.

Yes.

Right.

You look inside and you can see

there's an opening in the nose.

Right.

You have openings in your

nose too, for obvious reasons.

Um, there's some breathing purposes

going on there and there's maybe

some more airspaces in this skull.

It's a little hard to see because.

Skull, and it has an

exterior bone structure.

This giant beaver.

In my other hand, you can see is

because of the way it's been preserved.

You can see a lot more inside and you

can see there's a big opening in here.

Big open space in there

where the spine would've.

That?

That is where the spine, you can

see on the, on the, where the

vertebra come off, that hole, the,

the FRA at the back of the skull.

So there's a big opening in there and

you can sort of stick your finger down

in and see, it goes pretty far down.

And then you can look up its nose

and you can see in the modern beaver

that opening stops maybe an inch

or so in, in the giant beaver.

There are all of these pockets

of openings and they connect

way back in here into the skull.

So that brain case opening is very

small compared to this other giant

opening in the front of the skull.

But there's this big opening behind the

nose, reminiscent of whales of things that

communicate underwater, things that have

resonant chambers for making big sounds.

I mean, we don't know for sure.

But it really kind of makes you

think that the giant beaver was

making a lot of sounds clicks and

words, and maybe big booms and

maybe it was resonating in there.

We don't know the soft structures

that would've been in there because

those have not been preserved someday

as the Tundra thaws, we're going to

find a fully fleshed, giant beaver.

And the first thing I wanna

know is what's inside that big.

What do those structures look like?

There is a researcher, Beth

Rinaldi, and she got a 3d.

She got a CT scan of giant beaver

skull and was not this one, not this

one and was able to print, essentially

print that empty space and turn it

into a horn so that she could play

the sound of the giant beaver horn.

And when we go downstairs, I'll

see if I have that recording on

my phone and play it for you.

Because I went to her house once I heard

that and I happened to be passing through

Kansas, which, where she was at the

time I sent her an email immediately and

said, I'm going to be there in December.

Can I come to your house?

and she said, sure.

so I showed up and I'm

coming to your house.

Exactly.

And she played the giant

beaver horn for me.

Stay tuned for more about how

this ice age giant becomes a D&D monster,

but I just want to briefly tell you

how you can take it home to your table.

The giant beaver is one of more than a

dozen Plieistocene megafauna appearing

in Book of Extinction, a bestiary of

extinct species for 5th edition coming

to Kickstarter in March of 2023.

You can get the most recent playtest

release of Book of Extinction by joining

the Mage Hand Press Patreon family of

nerds at Patreon dot com slash m f o v.

The giant beaver appears alongside

the giant short-faced kangaroo, the

glyptodon, and the saber-toothed tiger.

You'll also meet prehistoric

lycanthropes like the dire werewolf,

the cave werebear, and the weremammoth.

That's Patreon dot com slash m f o v.

Patron or not, you can get the first

three monsters in the Book of Extinction

- the passenger pigeon, the great auk,

and the Tasmanian tiger - right now at

Scintilla dot Studio slash extinction.

Pay what you want for it, and anything

we earn will be donated to the

Center for Biological Diversity to

support their protecting endangered

species and wild places world wide.

All those links are in the description.

So I figured at some

point you were gonna ask me about

my experience playing Dungeons and

Dragons, which is not vast, and what

I thought about this animal as yeah.

You know, a real creature and

what its special traits are.

And also as a, as a magical creature.

So I've been thinking about

that for a little bit, and

I really think that ability.

That sound ability is pretty cool.

And I mean, just as an

actual living creature, the

ability to make those sounds.

And, and first as I, you know, my thought

processes have, have changed over time.

Um, you know, like I was pointing

out before with ASOS, we used to

think they were tail draggers.

Now we think that their tails were upright

and we used to think they were maybe just

green and scaly, you know, we think, oh,

they could have been all different colors.

Right.

They could have had lots of different.

And we've changed our opinion of

what the giant beaver looked like.

I've been understanding more, um,

about her and I think a lot about her

impact on the environment around her.

And I was thinking if you're not cutting

down trees, you're not building dams.

You're not building lodges.

You're not like the ecosystem

engineer of the modern beaver.

What are you really doing anyway?

but I do think.

that she was keeping those

ponds clear of vegetation.

If she was eating a lot of reeds

and macrophytes, all that pond,

weed, those ponds, weren't those

dense places that you think of.

Now, when you're thinking of a wetland

where you can't get up to the water,

there's so much vegetational around it

and they get filled in pretty quickly.

I bet with her insatiable appetite.

She was really moving a lot

of vegetation out of there.

And I would bet with those incredibly

strong back legs, she could have been

moving stuff out of the bottom of the

ponds and keeping them big and open.

And she could have been making sounds that

would've carried in these big spaces and

maybe through waterways as well, because

she would've been clearing the waterways.

Cuz I was thinking you make a sound

underwater in a, in a stream, in a pond.

It's not gonna carry very far, cuz

there's so much stuff around in there

that we'd just soak up that sound.

I maybe not, maybe she was moving

things around and creating a space

that would let her sounds travel.

So I think if she were mythical that

her sounds, if they were clicks and

words, Might do slashing damage.

I think that maybe if it was more

of a resonant chamber, she could be

making a boom that would flatten you.

I think that she's got some powers

with the, with her massive airspace.

When did you start playing?

What's the what's.

What, what kind

of a part of your life at first?

Okay.

I first played a game in graduate

school with some friends um, and

I think maybe it was maybe a more

traditional game, definitely more

traditional than my next game ion.

It was, I don't know anything about it.

Sure.

This is my level of experience,

but what I do know is.

Fighting random things.

I just wasn't, I wasn't super into it.

I felt like I wasn't sure

I wasn't doing it right.

I didn't know what I was doing.

There was so much fighting

and there was like weapons

and I wasn't really into that.

And then I became director of the Joseph

Moore museum many years down the road.

And I took students to New Zealand

for a study abroad program.

And one of my students was a DM who

is also a great natural historian.

loves organisms loves knowing about the

natural world and when he understood

or when they understood what I really

like, they were able to design a game

that was perfect for me, which was, I

just wanna hang out with the animals.

I want to talk with them.

I want to do things with them.

And if there are animals

around, I am into it.

but when they're not like, okay,

when's the good stuff happening.

So in this game, my goal was to make

friends with every animal we found.

And so everywhere we went, I

asked if I could look for animals.

I asked if I could talk to animals.

And I got very lucky with some early roles

and we met a giant bear and I rolled a.

And so that bear became part of our group.

that bear, every time you

did a check, that bear was

still fully part of our group.

every time I happened to get a

great role and we approached a

town with this giant bear yeah.

And needed to get in and the gatekeepers

like, well, um, uh, no, right.

I don't think so.

And we, right.

And then I said, I'm sorry,

we don't have a bear.

That's uncle.

And it turned out that my deceit

or whatever that's called, I

rolled really well on that.

And so then uncle Jim was just

uncle Jim came into the town

with us and stuck with us.

okay.

And that made a great game.

So McGee Catlett was that student

and they did an incredible

job as a, as a DM for me.

And it got me very interested in

playing or, and now my husband,

who's a physics professor here.

Just started running

a game for our family.

We have three kids.

And so he's been learning how to run a

game so that we can adventure together.

Thanks for listening to

Extinction.

Many thanks to Heather Lerner and the

Joseph Moore Museum at Earlham College for

providing this behind the scenes tour and

opening my eyes to the hidden possibilites

in paleo art and DNA reconstruction.

The extinction of megafauna tells

us so much about how we relate to

the natural world, and I'm excited

to add what I learned from this

trip to the Book of Extinction.

Do you like maybe things that get

going on ways to get involved with

the museum work that you're doing,

that you want people to know?

Yeah, I would say one

thing is you can see her yourself.

We are just off I 70.

So if you're ever traveling across

the country and many people.

You'll be on I 70.

Yeah.

So we're pretty easy to find we're

open every afternoon from one to five

except Tuesday and Thursday year round.

And we also have an escape game that

features the giant beaver and your

goal during the escape game is to

rescue the giant beaver from a fire.