I want you to close your eyes for a second. Just
picture the Caribbean. Oh, that's easy. White
sand or the turquoise water. Right. Exactly.
You're probably seeing that pristine travel brochure
version. Maybe there's a cruise ship docked way
out in the distance. Someone handing you a very
colorful drink with a little paper umbrella in
it. Yeah. Paradise. It is. Well, it's the modern
definition of paradise, but that's a really surface
level view of what those islands actually are.
It really is. Yeah. So let's peel back that layer.
of the all -inclusive resorts. I wanna zoom in
specifically on the islands of Antigua and Barbuda.
Okay, zooming in. And now we're gonna turn the
clock back. How far back are we talking? Oh,
way back. We aren't going to the Pirates. or
even to the arrival of Columbus. Right. We are
going back thousands of years. Before the very
first human footstep ever disturbed that white
sand. Exactly. To a time when those islands were
louder, wilder, and honestly much stranger than
they are today. A completely different world.
In this ancient version of Antigua, there's a
creature moving through the underbrush. And it
isn't a bird. It isn't a reptile. Right. Which
is what you'd expect on a remote island. Right.
It's a mammal. Yeah. And it is not small. Definitely
not small. We're talking about something the
size of a large house cat. Maybe even a small
dog. It's robust. It's furry. And it is the undisputed
king of the ground. And here's the real kicker
about this animal. It survived incredibly long
odds just to get there. Unbelievable odds. It
thrived for millennia. And then in the blink
of a geological eye, it vanished. Poof. Gone.
But that is not actually the strangest part of
this whole story. No, the strangest part is its
current status today. because usually when we
talk about extinct animals, you know, dinosaurs,
dodos, the woolly mammoths. We know their names.
Exactly. We know their names. We have the museum
t -shirts. We have the lunchboxes. The whole
branding package. But this creature, you can
go to a museum right now today. Like the University
of Florida or the Smithsonian. Yeah, and you
can literally hold its skull in your hands. We
have the bones. We have all the measurements.
We know exactly where it lived, what it ate,
who ate it. We have so much data. But if you
open the official rule book of zoology doesn't
exist it does not it's a biological reality But
legally it's a taxonomic boast So today we're
doing a deep dive into this ghost of the Caribbean.
I love that title a massive extinct rotant that
is technically completely nameless due to this
bizarre bureaucratic loophole that has lasted
for over 60 years. We're talking about the creature
that is known informally as Echplotomies. Echplotomies.
Or, as the scientific literature rather coldly
prefers to call it, Undescribed Species B. Undescribed
Species B. I mean, that sounds like a vitamin
supplement, not a giant island conqueror. It
really lacks a certain grandeur, doesn't it?
It's a terrible name for a king. It is. But the
story behind that lack of a name is almost as
fascinating as the animal itself. For this deep
dive, we're going to be heavily referencing a
specific Wikipedia entry that details the taxonomy,
the morphology, and the history of this creature.
And that entry is primarily built on the foundational
work of a paleontologist named Clayton E. Ray.
Clayton Ray, he's really the central detective
in this whole mystery. He absolutely is. Okay,
let's unpack this, because I'm reading the source
material and it sounds like something out of
a Kafka novel. It's very bureaucratic. How can
an animal be sitting in a drawer at Harvard,
fully fossilized, fully described in writing,
and yet the scientific community collectively
says, nope, never heard of it? To really wrap
your head around that, we have to talk about
the rules of the game. OK, the rules. Zoology
isn't just about going out into the field and
finding cool bones. I mean, that's part of it,
but it's also about paperwork. Lots of paperwork.
There is an official governing body called the
ICZN. Which stands for? The International Commission
on Zoological Nomenclature. Wow. Yeah, they are
basically the Supreme Court of Animal Names.
The Supreme Court of Taxonomy. I imagine their
meetings are very lively. They are incredibly
precise, let's put it that way. But they have
to be. Their job is to prevent total chaos. Think
about it. If we didn't have strict universal
rules, you'd have, say, five different scientists
discovering the exact same species of beetle
on five different expeditions. Then they'd all
give it a different name. Exactly. You'd have
five different names in the literature, and no
one would know that they were all talking about
the same bug. science would grind to a halt.
Okay, so I get why the ICZN exists. They need
a strict code on what counts as a legally published
name so everyone is on the same page. Right.
And that brings us to Clayton Ray. Enter our
detective. So rewind the clock to 1962. Clayton
Ray is a PhD student at Harvard University, and
he's writing his thesis on the rodents of the
Antilles. The Caribbean islands. Yes. He's examining
these subfossil and fossil collections from Antigua
and Barbuda. And as he's looking at these bones,
he realizes he's holding something entirely new.
It's not just another rat. No, this is a monster
rat. It's totally distinct from anything else
on record. So he does what a good scientist does.
He does the work. He does a brilliant job, actually.
He measures the skulls. He painstakingly describes
the teeth, the morphology. He figures out exactly
where this giant fits in the mammalian family
tree. He maps it all out? He maps it out, and
he names it. He gives it the species name, Orizomis
hypoidemus. Orizomis hypoidemus. And he even
creates a brand new subgenus for it, which he
calls ecblutimus. So he typed this all up. He
types it all up, gets it bound into his thesis,
and he submits it to the faculty at Harvard.
He defends it, gets his PhD. He gets his doctorate.
And that physical thesis document goes right
into the Harvard Library archives. OK, so case
closed, right? The giant rat. has a name. It's
written down at Harvard. You would really think
so. But here is the massive loophole. I'm bracing
myself. According to the International Code of
Zoological Nomenclature. The Supreme Court. Right.
According to their rules, a universe of thesis,
especially one from 1962, is not legally considered
a published work. Wait, hold on. It's sitting
in the Harvard Library. Yes. Any researcher can
walk in, request it, and read it. They can. Other
scientists have literally cited it in their own
papers. How was that not considered published?
It all comes down to their strict definition
of public dissemination. Public dissemination.
The ICZN logic is that a thesis is essentially
an internal academic document. It's a final exam
for a student. An incredibly long final exam.
Exactly. But it wasn't printed in a recognized
scientific journal. It wasn't distributed to
thousands of libraries and universities globally.
It wasn't put out for the mass scientific public.
Right. In the legal taxonomic sense, it wasn't
made formally available. So because he didn't
take that specific cha... of his thesis and mail
it off to Nature or Science or the Journal of
Paleontology. The names don't count. That is
wild. Because he never formally published that
exact taxonomic description in a wide -release
format, the names Orizames, Hypememus, and Echblitemes
are legally considered unavailable names. Unavailable.
It's like a squatter. It's living in the house
of taxonomy. Everyone knows it's there, but it
doesn't actually have the deed to the property.
That seems... I mean, I get the need for rules,
but that just seems incredibly pedantic. It's
deeply pedantic. We've known about this animal
and its proposed name for over 60 years. Everyone
in the field knows what eculotomies is. They
do, but science relies on that pedantry to function
consistently across centuries and across language
barriers. I suppose. But you're right, it does
leave us in this weird, frustrating limbo where
we essentially have to use the name in quotation
marks. Which is why we're calling it a ghost
species. Exactly. It's fully visible to anyone
who opens the drawer, but legally, on paper,
it's invisible. Well, ghost or not, I really
want to talk about the name that Clayton Ray
tried to give it. We should. Because usually
when you read scientific names, they're just
dry Latin descriptors, right? Like largefoot
or redhead. They're very literal. But Ray got
surprisingly poetic with this one. He really
did. He wasn't just describing bones. He was
telling a story with the etymology. Let's break
that down. Start with this species name. OK.
The species name is Hypenemus. Hypenemus. Which
means what, exactly? It derives from the ancient
Greek word Hypanemos. Okay. And that translates
directly to Leeward. Leeward? As in the Leeward
Islands? Exactly. Geographically, Antigua and
Barbuda are part of the Leeward Islands chain
in the West Indies. So he's anchoring the animal
to its physical home right there in the name.
That's right. But the subgenus name, ekbletomys,
that's the one that really paints a vivid picture.
Ekbletomys. It's a portmanteau, right? It is.
It's a combination of two Greek words, ekbletos
and phlos. OK. Well, I know moos is the standard
root for mouse. Right. What is ekbletos? Ekbletos
means cast up or thrown out. Cast up. So put
it together. The cast up mouse. The cast up mouse.
That is so evocative. I mean, the cast up mouse,
it immediately makes me think of a shipwreck
or a a survivor washing ashore on a piece of
driftwood. Which is precisely what Ray intended
when he chose it. Really? Yes. He chose that
specific imagery because it hints at a very specific
scientific theory, the rafting theory. The idea
that this animal didn't just walk across a land
bridge to get to Antigua... No, it was washed
ashore. It was a literal castaway. We are definitely
going to get into the details of that voyage.
The source material calls it a Sinbad voyage,
which is... Just a fantastic phrase. It's an
epic journey. But before we send our giant rat
out to sea, I think we need to get a much better
handle on what this animal actually looked like.
Physically, you mean? Yeah, structurally. Because
earlier you said it was the size of a large house
cat. Give or take, yes. But when I say the words
rat or mouse to you, I think most people, myself
included, have very specific ingrained image.
Sure. We picture a subway rat. We'd picture a
pest, something small, skittish, darting along
a baseboard. Right, and you need to completely
erase that image from your mind for this. Erasing.
This is not a subway rat. Echblutomys belongs
to a group known as the orizomenes. Orizomenes?
The common name for that group is the rice rats.
Okay. But even within the rice rats, Echblutomys
was an absolute giant. So in the world of Caribbean
rodents, this was basically megafauna. It was.
It was the largest known orizomene. How big is
megafauna when we're talking about a rat? Give
us a comparison. We often compare its scale to
another famous extinct Caribbean giant called
Megalomys dysmoresti. Megalomies, mega mouse.
Exactly. These animals were incredibly robust.
We are talking about a body length that could
potentially be over a foot long. And that's not
even counting a very long, thick tail. Wow. They
were heavy, muscular creatures. If you saw one
of these walking around today, your brain wouldn't
immediately register, eek, a mouse. Oh, what
would I think? You'd probably think, is that
a beaver? Or maybe a huge muskrat? It had real
physical presence. It had undeniable presence,
and we know this because of the skull. The source
material goes into a ton of detail about the
exact skull measurements, millimeters and ratios.
It gets very granular. And I know usually when
we start reading off millimeter measurements
of old bones, people's eyes tend to glaze over
a bit. Oh, absolutely. It sounds like dry data.
But in this case, those specific bone measurements
are everything, right? They're the only way we
know for sure that this isn't just the exact
same rat they found on the next island over.
That is the critical point. That's why the measurements
matter so much. Explain that. See, the Caribbean
historically had a few of these giant rats. We
mentioned megalomies, which lived on islands
like Martinique. So if you're a slightly lazy
scientist back in the day looking at a drawer
of big bones from Antigua, it would be very easy
to just shrug and say, eh, they're all just big
rats. They're all the same basic thing. Right.
Big rat A on Martinique, big rat B on Antigua,
probably the same species they just swam across.
But Ray didn't do that. Ray looked closer. He
looked at the holotype skull of Eclitmus, the
primary reference specimen, and he saw something
fundamentally structurally different from megalomus.
What did he see? He zeroed in on something called
the interorbital region. Okay, let's help everyone
visualize this. Where exactly is the interorbital
region on a skull? Okay, put your fingers on
your own temples. Right, fingers on temples.
Right between your eyes and your ears, that bridge
of bone that sits just behind the eye sockets.
I feel it. In most animals, and notably in the
neighboring giant megalomus, this area is quite
broad. It's wide. Yes. It forms a wide, sturdy
highway of bone connecting the face to the main
brain case. It's a wide forehead. Exactly. But
when Ray examined a cabal de mace, he found that
this exact space is aggressively constricted.
Constricted how? It is severely pinched inward.
In fact, it is narrower than in any other rice
rat known to science. Pinched like he was put
in a vice grip? Morphologically speaking, yes.
Imagine looking at the top of the skull and it
looks like an hourglass. OK, I see that. The
waist of that hourglass right between the eyes
is incredibly thin. That's the defining feature
of the skull roof of egg boltomies. But why does
that matter? I mean, is it just a cosmetic quirk?
Just a case of, oh, well, this family has a narrow
face. No, not at all. In biology, especially
in functional anatomy, form always follows function.
OK. That specific part of the skull, that interorbital
region, is where the temporal muscles attach.
The temporal muscles. Those are for chewing.
Yes. Those are the big, powerful muscles that
control the closing of the jaw. Oh, interesting.
So when you change the architecture of that skull
roof so drastically when you pinch it in, you
are fundamentally changing the leverage and the
structural integrity of the entire head. You're
changing how the machine works. Exactly. You
changed the bite force. So this narrow skull
implies that Ekbultemes was eating differently
than its neighbors, using its mouth in a totally
different way. It strongly implies a deep evolutionary
divergence in their diet and behavior, you don't
just develop a heavily pinched skull overnight.
It takes time. That kind of major structural
redesign takes hundreds of thousands, maybe millions
of years of complete genetic separation. Wow.
So that narrow hourglass shape proves beyond
a doubt that Ekbultemes isn't just a megalomys
that decided to move to Antigua. It's not a cousin
who just hopped a fairy. No, it represents a
completely separate lineage, a totally different
branch of the family tree that just happened
to end up in the same geographical neighborhood?
That is fascinating. And there's another detail
about the mouth architecture in the source material
that really stood out to me. The palate. Or the
teeth. Well, both really. Yeah. The palate is
described as being very short, barely extending
past the third molar. Right. And the insides
of the foramina, which are those holes in the
roof of the mouth, are also extremely short.
Yes, very compact. But the teeth are what really
caught my eye. The text says it had massive molars
but slender incisors. Yes. The dental profile
is incredibly telling. So translate that for
us. What does having huge back teeth but skinny
front teeth actually tell us about what this
giant rat was doing for dinner? Think about teeth
as tools in a toolbox. Okay. If you have huge
heavy complex grinding molars in the back of
your mouth, you are built to process something
tough. Like what? Maybe... coarse fibrous island
vegetation, maybe really hard seeds. You are
an anatomical grinder. The grinder. But then
look at the incisors, the front biting teeth.
They are slender, relatively delicate for an
animal this size. Now, compare that toolbox to
the neighbor, megalomies. Megalomies had noticeably
smaller molars, but absolutely massive, thick,
robust front incisors. So megalomies was using
its front teeth. as the primary tool. Yes. Megalomies
might have been cracking up in really hard nuts
or gnawing through tough wood using those big
front teeth almost like chisels. So Megalomys
is a cracker, and Iqblotemis is a grinder. Exactly.
And this tells us that even though they were
both giant rats living on Caribbean islands relatively
close to each other, they had evolved to fill
completely different ecological niches. They
weren't just carbon copies of the same survival
strategy. Not at all. It really emphasizes the
idea that the Caribbean wasn't just this generic
uniform basket of tropical islands. Each island
was its own world. Each one was a unique, isolated
laboratory of evolution. Laboratory is the perfect
word for it. Isolation is what breeds biological
innovation. Because there's no gene flow from
the outside. Right. When you stick a small animal
on a remote island and just leave it completely
alone for a million years, it starts to get weird.
It has to. It solves the basic problems of survival
in highly unique, localized ways. Atblitomies
solved the problem of surviving on ancient Antigua
by becoming a massive, narrow -skulled grinding
machine. But to become a weird islander, you
first have to actually get to the island. Ah,
yes, the hardest part. Which brings us to section
three of our outline, The Voyage. The Sinbad
Voyage. I just love that Clayton Rae used that
specific comparison, because if you pull up a
map, Antigua and Barbuda are, well... they are
not close to South America. They are deeply isolated.
They're way up the northern end of the Lesser
Antilles chain. To get there from the mainland
coast to South America, you have to cross a tremendous
amount of open ocean. So, logically, the most
obvious theory for how a rat gets there would
be island hopping, right? Like stepping stones
across a pond. Yeah. You swim or drift a short
distance from Venezuela to Trinidad, then you
establish a population there, then maybe a few
generations later, some wash over to Grenada.
Then St. Vincent, St. Lucia, Martinique, Dominica,
Guadalupe. Right, just working your way up the
chain, island by island, over thousands of years.
That is the intuitive theory. It feels logical
and safe. But Ray totally rejected that idea
for ectyltomize. He did. He looked at the data
and said, no, that's not what happened. Why?
I mean, taking it in short hops seems infinitely
easier than doing it in one massive shot. Ray
looked closely at the geology and the bathymetry.
the ocean depth of the region, even during the
Pleistocene Epoch, the Ice Age, when global sea
levels were drastically lower because so much
water was locked up in the polar ice caps. The
islands would have been bigger then, right? More
exposed land? They were larger, yes. But the
deep ocean channels between those islands, those
remained. They were still massive, turbulent
water barriers. So it wasn't a land bridge situation?
Not at all. Ray calculated that to get from the
South American mainland all the way up to Barbuda
by hopping, this specific lineage of a rat would
have to successfully cross at least seven distinct
deep water ocean barriers. Seven times they'd
have to brave the open ocean and win. Seven consecutive
miracles. You have to launch a few individuals
into the water. They have to land safely on the
next island. establish a viable colony, thrive
there, outcompete whatever's already living there.
And then eventually launch another population
into the water to the next island. Right. And
Ray argued that the mathematical probability
of doing that seven times in a row, and crucially,
without leaving any fossil trace of this specific
lineage on the intermediate island. Because we
don't find Ichblochemies on Grenada or St. Vincent.
Exactly. To do all that without leaving a trace
is statistically, practically impossible. So
that's where the quote comes from. Yes. Ray wrote
that a series of successful sequential voyages
like that would be, quote, no less wondrous than
those of Sinbad. So if they didn't hop from island
to island, they must have. rafted in one straight
shot. The rafting theory, also known in biogeography
as the sweepstakes route. Sweepstakes route.
That name implies that most people who enter
the sweepstakes lose. Almost everyone loses.
A sweepstakes route is a high stakes, extremely
low probability dispersal event. Okay, I need
you to really paint the picture for us here.
Because when you say rafting rat, my brain immediately
goes to a cartoon. Like a rat tying some twigs
together with vines and raising a little leaf
sail? Exactly. Stuart Little on the high season.
What is a natural raft actually like? OK, you
have to picture the great massive river systems
of the South American continent. Like the Orinoco
or the Amazon. Exactly. Imagine a massive catastrophic
storm, a huge hurricane system, or maybe just
unprecedented seasonal flooding high up in the
mountains or the rainforest. The water levels
rise rapidly. The river swells enormously. It
becomes a torrent and it starts undercutting
its own muddy bank. And the land just collapses
into the churning water. Huge intact chunks of
the forest floor. We are talking about dense
mats of vegetation, tightly interlocked tree
roots, fallen trunks, vines, thick soil. Like
floating islands of dirt and wood. Yes. Some
might be the size of living room. Some might
be the size of a whole house or even larger.
Wow. These massive mats float rapidly down the
swollen river and eventually get blasted right
out into the ocean. And if our little rat ancestor
just happened to be sitting on that particular
piece of land when it gave way. There's suddenly
a passenger on an ocean voyage. And I'm guessing
this is not a luxury cruise. It is an absolute
nightmare. I can't even imagine. You are drifting
helplessly in the strong Caribbean currents.
The sun is beating down on you relentlessly.
Tropical sun. No canopy cover. No shade. And
worse, you have absolutely no fresh water. Just
whatever rain happens to fall. Right. You are
constantly battered by salt spray, which is dehydrating
you further. You have to endure ocean storms
that are actively trying to break your fragile
raft apart. And you have to survive this horrific
ordeal for, realistically, how long? To drift
from the mouth of the Orinoco all the way up
to the Leeward Islands, you are looking at weeks.
Weeks? Maybe even a full month at sea. A month
on a floating tangle of roots with no water.
And here is the truly crucial mind -bending part
of the sweepstakes. It cannot just be one tough
male rat that survives this. Because one male
rat does not build a population on a new island.
Exactly. You need at least a pregnant female
to survive the trip. Or a breeding pair that
somehow both make it. The odds against that seem
genuinely astronomical. It feels impossible.
It is effectively impossible in any human timeframe.
If you stood on the beach for a lifetime, you'd
never see it happen. But here is the magic of
deep geological time. If you give the impossible
a million years to happen, it eventually becomes
inevitable. Exactly. If you roll the multi -sided
dice every single major flood season for two
million years, eventually one day you roll that
perfect double six. So one day, against literally
all the odds in the universe, this battered,
shrinking raft of vegetation, with a very thirsty,
very traumatized, pregnant rat clinging to it,
crashes onto the pristine white limestone shores
of Barbuda, cast up, Now you see why he chose
that name. It hits so much harder now. It really
was physically cast up by the sea. And once they
finally stumble off that raft onto the dry land,
the entire game of survival changes. They are
in a totally new world. And Ray actually had
a very strong theory about exactly who was on
that original raft, didn't he? Where they originally
came from on the mainland. He did. By closely
analyzing the skull morphology, he pointed to
a mainland species called Orizomys albigularis
as the closest living relative. OK. As a quick
aside, taxonomy never sleeps. So today, that
specific species has actually been moved by geneticists
into a new genus called Nephelomys. Nephelomys.
But the common name is really the key detail
here. They're known as the cloud forest rats.
Cloud forest, that sounds cold and wet. It is.
These are rats that live high up in the Andes
Mountains and in the cool high altitude highlands
of Panama and Venezuela. They live in misty,
chilly, wet mountainous forests. Exactly. It
seems like the exact opposite of a sun -baked
Caribbean beach on Antigua. It is as different
an environment as you can get, but they share
the underlying skull architecture with our island
giant. So they have that same robust brain case,
the specific crests on the bone? Yes. Which heavily
implies that the small ancestor of eclatomace
somehow washed down from those cool mountains
during a flood, survived the brutal tropical
ocean crossing, and then had to immediately adapt
to a radically different, dry, scrubby climate
on Antigua. Talk about culture shock. You go
from the misty, cool Andes to a limestone scrub
forest at sea level in the Caribbean. It's extreme.
And that intense environmental pressure combined
with the isolation is what drove the gigantism.
The gigantism. because they didn't start out
giant. No, the ancestor was relatively small.
This transformation is an example of a classic
biological principle called the island rule.
The island rule. Is that the one where small
things get big and big things get small? Exactly
that. Foster's rule. If you are a large animal
on the mainland, like an elephant, and you get
trapped on an island - You shrink. Right. You
become a dwarf elephant over generations because
there simply isn't enough food or land to support
massive bodies. But if you are a small animal,
like a rat - You get huge. Why? Why is - bigger,
suddenly better for a rat on an island. It's
a combination of several factors. First and foremost,
a total lack of predators. Right. On the South
American mainland, if you are a rat, you stay
small so you can hide in tiny crevices from jaguars,
ocelots, foxes, eagles. Everything wants to eat
you. But on ancient Antigua, there are no mammalian
carnivores. None. No wild cats, no wolves. You
are perfectly safe. You don't need to scurry
and hide in tiny holes anymore. You can relax.
Okay, safety is one thing. Second is competition.
If there are limited resources and you are slightly
bigger than your siblings, you can physically
bully other members of your own species to get
the best food. Size gives you dominance. And
third, which is very important for our grinding
rat, is metabolic efficiency. A larger body mass
with a longer digestive tract actually helps
you process the coarser, lower quality vegetation
that you find on a dry island. Which perfectly
aligns with those massive grinding molars we
talked about earlier. Exactly. It all fits together.
So over thousands and thousands of generations,
this little, terrified, cloud forest refugee
slowly puffs up into the giant, confident Ekbultemis.
And it essentially becomes the dominant terrestrial
mammal of the entire island system. I really
want to talk about what that daily life was actually
like for them. The ecology. Yeah, because reading
the source material, we actually have a surprisingly
vivid detailed picture of the exact ecosystem
Iqbaltami's lived in. We do. We know its neighbors.
And we know this thanks to... of all things,
fossilized owl vomit. Yes, the absolute glamour
of paleontology. That's amazing. We honestly
owe almost everything we know about the small
extinct animals of the Caribbean to the burrowing
owl. Okay, you have to explain that process for
us. How exactly does an owl become the premier
fossil collector of the Caribbean? It's a field
of study called taphonomy. The study of how organisms
die, decay, and become fossilized over time.
And owls happen to be fantastic natural taphonomic
agents. Because of how they eat. Right. Owls
swallow their smaller prey whole. Rats, lizards,
little birds down the hatch in one piece. Gruesome.
But their stomach acids, while they digest all
the meat and soft tissue, they can't handle the
hard stuff. They can't digest bones, teeth, or
fur. So they have to get rid of it. So a few
hours after eating, the owl regurgitates a dense,
compact little pellet that contains all the clean,
perfectly concentrated bones of whatever it just
ate. It's literally like a pre -packaged, perfectly
curated museum exhibit just waiting to be found.
Precisely. And here's the key. These burrowing
owls, Athene cunicularia, they tend to live in
limestone caves or under rocky overhangs. And
they roost in the exact same spot year after
year. generation after generation for millennia.
So over thousands of years, these pellets just
drop to the cave floor and pile up. A mountain
of data. They break down, they get buried in
the fine cave dust and sediment, and they preserve
an absolutely perfect high resolution snapshot
of everything that was living and scurrying around
in the immediate area. So when Clayton Ray was
doing his field work excavating those sites in
Barbuda places with great names like Two Foot
Bay and Suffers. Or Mill Reef and Indian Creek
over on Antigua. Right. When he was digging there,
he was essentially just digging through thousands
of years of ancient owl toilets. That is factually
correct, yes. He described finding these distinct
layers of red to yellow, unconsolidated sediment.
Loose dirt? Loose, dry dirt that was absolutely
packed with thousands of microbones. So let's
use that data to reconstruct the scene. Let's
imagine it's, say, 2 ,000 years ago on Barbuda.
OK. We're standing outside the caves at Two Foot
Bay at twilight. What are we seeing and hearing
around us? Well, first of all, it's a very busy,
very noisy ecosystem. It is not quiet. OK. Based
directly on what we found in those owl pellets,
the ground all around you is just alive with
reptiles. Lots of lizards. Everywhere. You have
thecidactylus rapicata. Thecidactylus, what is
that? The common name is the turnip -tailed gecko.
Turnip tails. There are these big, chunky, very
vocal nocturnal geckos. So you hear them barking
and clicking. OK, clicking geckos. You also have
fast -moving ground lizards. It's darting through
the leaves, like fallidocilis grazoldi. Try saying
that three times fast. I won't. And up in the
branches, you have anolis litchi, the large tree
anoles. So there is just constant rustling in
the dry leaves. The ground is moving. And what
about the birds? The limestone cliffs and caves
would be echoing. The pellets show huge numbers
of seabirds nesting right there, especially shearwaters.
The puffinous species. Right. And shearwaters,
if you've never heard them, they make this incredibly
eerie, ghostly, wailing call when they return
to their nests at night. It sounds like a crying
baby or something, doesn't it? Like a crying
baby or a ghost moaning. It's very unsettling.
Creepy ambience. Very. Now, add the bats. The
sediment is full of bat bones. So the sky is
full of them. Huge swarms of mormoups and nautilus
bats sw - whirling around the cave entrances
at dusk, catching insects. And frogs. Yes, the
tiny whistling frogs, Aliferidactylus johnstoni,
calling constantly from the damp spot. So it
is an absolute cacophony. It is wild. We've got
peeping frogs, squeaking bats, wailing ghost
birds, clicking geckos. And moving through the
middle of all this noise and chaos is our giant
capillutomys. The king of the ground. It's big,
and compared to a skittish mainland rat, it's
probably relatively slow moving. It has no reach.
It's just lumbering along, foraging for tough
seeds. Maybe occasionally raiding one of those
shearwater nests on the ground to eat an egg.
And of course, occasionally getting snatched
up in the dark by a very ambitious burrowing
owl. Which frankly is impressive, because burrowing
owls are not huge birds. They are relatively
small, long -legged owls. So taking down a cat
-sized rat is a big deal. It suggests the owls
were probably mostly hunting the juveniles, the
younger rats, because of full -grown, heavy adult
ecboltomus might literally be too heavy for a
burrowing owl to lift. But the sheer number of
bones shows that this rat was a staple, everyday
food source. It was the primary protein bar of
the island ecosystem. Everything relied on it.
It really paints such a beautiful picture of
a highly functional, entirely self -contained
world. It does. You know, we so often think of
islands as these fragile, broken ecosystems just
waiting for humans to arrive and mismanage them.
But this was working perfectly find without us.
It was a perfectly balanced equation. The lizards,
the giant grinding rats, the owls, the bats.
They had all been dancing this intricate evolutionary
dance together for thousands of years. Until
the music completely stopped. Until the music
stopped. And this brings us to the harsh reality.
Section five of our outline. The extinction event.
The end of the line. We know, obviously, that
eclatomace is gone today. The big question is,
who killed it? Well, in paleontology globally,
we argue about extinction causes all the time.
Was it an asteroid? Was it a volcano? Was it
climate change? Right. But when you are studying
the extinction of endemic Caribbean mammals,
the answer is almost always painfully the same.
And the definitive evidence for that answer is
buried right there in the dirt of those caves,
isn't it? It is written clearly in the stratigraphy,
the physical layers of the cave floor. Walk us
through those layers because this is fascinating.
Think of the cave floor deposit as a giant layer
cake of history. Okay, a cake. The thickest,
bottom -most layer of that cake is that yellow
to red loose sediment we just talked about. The
owl pellet layer. Right. That thick layer represents
the old world. It is absolutely packed with the
bones of Ekbuldemiz, the native geckos, the local
bats. And chronologically, how much time does
that yellow layer cover? It spans many thousands
of years. It dates from the late Quaternary,
the Pleistocene Ice Age, all the way up through
the Holocene. Meaning it continues right up through
the arrival of the very first humans in the Caribbean.
Yes, that's a crucial point. The giant rat actually
survived the first waves of human arrival. Who
were they? The Amerindians, primarily the Saladoid
peoples, they arrived in Antigua and Barbuda
roughly around 2500 BCE. So they shared the island.
They did. We actually find Ekwodamese bones mixed
into the archaeological middens, the ancient
trash heaps of these indigenous peoples. Meaning
they were hunting and eating the giant rats.
They were. It was a large, meaty animal. But
hunting them didn't wipe them out. No. The overall
population of the rats might have dipped slightly,
but they had coexisted for a very long time.
The indigenous hunting and agricultural practices
were relatively low impact compared to what came
later. They didn't completely clear cut the habitat.
Exactly. The giant rat and the indigenous humans
shared those islands for over three millennia.
OK, so looking back at our soil cake, we have
this thick yellow layer showing humans and giant
rats living together. Then what happens is you
move up the dirt. Then you hit a very sharp,
very sudden line in the soil. The yellow dirt
just stops abruptly. And right above it, sitting
on top, you get a distinct layer of very dark,
organic, rich sediment. The dark layer. That
sounds incredibly ominous. It is the stark boundary
line of the colonial era. And in that dark sediment
layer, Ekboldimis just vanishes. The bones disappear
completely. It is entirely absent from the upper
record. And what replaces it in that dark soil?
Raddus. Raddus. The European rats. Specifically,
Raddus raddus, the black rat, and Raddus norvegicus,
the brown rat. The ship rats. And crucially,
raddus does not cross oceans by rafting on random
mats of vegetation. No. Raddus travels comfortably
in the holds of massive wooden sailing ships.
The sudden appearance of Raddus bones in that
upper layer is the definitive geological marker
for the arrival of Europeans post -1500 AD. It
is amazing. in a sad way, that the geology is
that incredibly precise. Yeah. You can literally
drag your finger up the cave wall and see the
exact moment Columbus and the subsequent colonizers
arrived. It is a stark, devastating line in the
earth. One world ends entirely, and a completely
different one begins. So why exactly is the European
rat such an unstoppable killer in this scenario?
I mean, think about it. Ekbultemis is a giant.
It's the size of a cat. Rattus is relatively
small. Sure. In a one -on -one cage match, I
am absolutely betting my money on the giant Caribbean
rat. And in a pure physical cage match, you'd
be right. Agultamese wins easily. But evolution
and extinction isn't a cage match, it is a numbers
game. A numbers game. And Rattus is the ultimate
biological cheat code in the numbers game. How
so? Unpack their strategy. First and foremost,
rapid reproduction. They breed fast. Insanely
fast. An island giant like Ekbultemes, having
lived with zero predators for millions of years,
almost certainly evolved a very slow life history.
Because they didn't need to replace themselves
quickly. Right. They likely had fewer babies'
poo litter, a much longer gestation period, and
took a longer time to reach sexual maturity.
Whereas the European rat... Explodes in population.
The giants simply could not reproduce fast enough
to sustain their numbers under new pressure.
They just swarmed them. Swarmed. Second... Rattus
is a highly aggressive, hyper -adaptable generalist.
They will eat literally anything. So they stole
the food. They absolutely would have outcompeted
Iqbaltomys for the seeds and plants it relied
on. But much worse, European rats are notorious
egg and nest predators. They likely hunted and
ate the juvenile Iqbaltomys right out of their
nest before they could ever grow into giants.
So they cut off the next generation. And finally,
perhaps the most deadly factor, disease. Biological
warfare. Almost certainly. Bratis carries a whole
host of continental pathogens, fleas and viruses
that the native isolated island rodents had absolutely
zero immune defense against. It's the exact same
tragic story as the human populations of the
Americas encountering European diseases. It is
a terrible parallel. Yes. So the extinction wasn't
a giant battle. It wasn't a bang. It was just
a whimper, a slow choking, inevitable squeeze,
a deadly squeeze, but one that happened incredibly
fast in geological. time. Within just a few short
decades of European ships dropping anchor, a
unique biological lineage that had successfully
survived for millions of years was completely
wiped out. And it wasn't just limited to Antigua
and Barbuda, was it? The outline mentions this
mysterious, undescribed species bee showing up
elsewhere. Yes. And this is where the scale of
the tragedy really widens. What did they find?
In recent years, archaeologists digging in middens
on other islands, specifically Guadalupe, Montserrat,
and Marie Galante, have found the scattered bones
of a very similar massive rice rat. Also labeled
undescribed species bee. Exactly. The morphology
is so close that it strongly suggests that either
Agbultimus itself or its very, very close cousins
were actually the dominant ground mammals across
that entire section of the Lua chain. They weren't
just a localized fluke. They were a regional
empire. They were a massive evolutionary success
story. They had conquered multiple islands. They
were everywhere. And they all fell to the exact
same enemy. The dark sediment layer is found
in the caves of all those islands. The story
is identically grim across the board. The wooden
ships arrive. The European rats disembark. The
native giants completely disappear. It really
brings us right back to the start of this entire
conversation. The profound irony of this animal's
existence. It is deeply, deeply ironic. If you
just take a step back and look at the resume
of the species. Let's review it. It starts out
as a small, shivering rat in the high, misty
cloud forests of the Andes. It gets swept into
a raging river, survives a brutal, seemingly
impossible Sinbad voyage across the ocean on
a tangle of roots, a literal miracle of survival
at sea. It washes ashore, a cast away. It conquers
an entirely new alien landscape. It fundamentally
changes its own biology. It reshapes its skull,
alters its teeth, and blows up its body size
to completely master that limestone terrain.
It survives massive Caribbean hurricanes. It
survives the rising sea levels at the end of
the global ice age when the islands shrink. It
even survives the arrival of the first spear
-wielding human hunters living alongside them
for thousands of years. It survives all of that.
But it could not survive the year 1500 AD. It
could not survive the globalization of the common
rat. And now, the final, most bitter irony of
all? It can't even survive the rigid bureaucracy
of human science. It sits quietly in a museum
drawer, permanently unnamed. A literal ghost
species. It really is a poignant reminder that
extinction doesn't just physically erase the
living animal from the earth. Sometimes, it eventually
erases the very memory of the animal from our
records. Which is terrifying. Think about it.
If Clayton Ray hadn't been incredibly diligent
in the 1960s, if he hadn't written that specific
brilliant thesis, we wouldn't even know enough
today to call it undescribed species B. It would
just be a box of weird oversized bones gathering
dust on a shelf. Just a geological anomaly nobody
bothered to look at closely. And that is the
one thought that I really cannot shake as we
wrap this up. We only know about this specific
ghost because Ray was diligent, but How many
other drawers are out there? Oh, that is the
big open question in paleontology. I mean, every
major natural history museum in the world, London,
Paris, New York, Washington, D .C., they all
have massive labyrinthine basements full of what
they call unprocessed material. Millions of specimens,
boxes of bones collected hastily by explorers
in the 1800s, fragile fossils dug out of quarries
in the 1920s that got packed away during a war
and never opened again. They're all just sitting
there in the dark. waiting for a story. Exactly.
How many other forgotten ghost species are currently
hiding in plain sight? How many other impossible
Sinbad voyages are locked away in a steel cabinet
right now, just waiting for a curious grad student
to pull open the drawer, take the millimeter
measurements, and finally write the right paper?
We tend to romanticize exploration. We think
it means going out into the unmapped jungle with
a machete and a pith helmet. But sometimes the
most important exploration is just going down
into the climate -controlled basement with a
pair of digital calipers and a strong cup of
coffee. The history of life on Earth is far from
finished. It is still being written, and a huge
chunk of it is going to be found quietly waiting
in the archives. I couldn't agree more. Well,
here is to epitomies. The cast -up mouse. May
it one day finally get its official name on the
deed. Here, here, I hope so too. Thanks for taking
this deep dive with us today. It was my absolute
pleasure. And we will catch you all on the next
one.