(upbeat music)
- Hi everybody, I'm Jen Sheridan,
the curator of amphibians and reptiles
at the Carnegie Museum of Natural History,
and today we're gonna be talking with
Matt Lamanna, the vertebrate
paleontology curator.
Is that your official title?
- Something like that, yeah.
- Okay, so we're trying out this new
curators interviewing curators,
or science staff
interviewing science staff,
and I'm gonna ask Matt a few questions
and we're just gonna have a conversation.
So, first of all, Matt,
I would love to know what
you've been working on
the last couple of weeks
since we've been working from home.
- Sure, yeah, so I'm very fortunate
in that I can do a lot
of my research from home.
And I've been, in particular,
trying to finish up
a couple of scientific papers,
drafts of scientific papers,
about a group of dinosaurs
called megaraptorids.
And this is a group that was pretty common
in the southern hemisphere continents
in the cretaceous period,
the third and final period
of the Age of Dinosaurs.
They were the kind of top predators
in a lot of their environments,
or at least we think they were.
But one thing that's really
cool about megaraptorids
is we don't know a whole lot about them
because their fossil
record is pretty poor,
so every time we have a
new specimen of this group
it has the potential to tell us
something we didn't
know before about their,
say, their evolutionary relationships,
their, kind of what they tell us
about the shape of the world at that time.
In other words, could dinosaurs
migrate from place x to place y?
Something like that.
Even things as fundamental
as what they looked like.
We actually don't know
even what certain parts of the skeleton
of these dinosaurs really looked like.
And so it's been really, really fun
and exciting to work on those.
I have actually a couple
of replica fossils
here at home of megaraptorids,
and so I'll show off one.
- So while you're getting
that, I have a question.
So is it, as their name
would sort of imply to me
as a non-paleontologist,
are they raptors that are very large?
- Well, so it's a really funny story,
and it sort of tells you about
how paleontology goes sometimes.
So I, when the first one
of these things was found
back in 1998 it was known
from only four bones.
And the scientists that named it
didn't really know what it was,
as you can imagine with just,
I mean think about you study frogs.
You have the whole organism,
you have its behavior, its
calls, its soft tissue anatomy.
In the best case scenario
we paleontologists
are dealing with maybe a whole skeleton
and like a little bit of soft tissue
like skin or feathers
or something like that.
And in most cases we're dealing
with tiny, tiny, tiny bits of skeleton.
So as you can imagine,
what we do is sort of
fraught with uncertainty
a lot of the time.
It's one of the most frustrating things
about vertebrate paleontology,
but also one of the most fun,
because we get to be,
in some sense, artists
in addition to scientists.
- Yeah, so, that kinda
leads me to another thing,
and I'm sorry to interrupt you,
and we can come back, but this
is really interesting to me,
because one of the things
I was thinking about is
I have this idea that in paleontology,
at least vertebrate paleontology,
kinda like you just said,
you're often really, you're
spending most of your time
either digging up bones
or describing species
from one to a handful of bone fragments,
so how accurate is that?
How often do you have
lots of bone fragments
or parts of the skeleton to work with?
And how often is it
just one or a few bones?
- It varies a ton.
The vast majority of dinosaur fossils,
and that's what I know best are dinosaurs,
are very incomplete, and so it does limit
kind of the amount of information
that you can get out of them,
and the reliability of the conclusions
that you can draw from them.
However, especially in recent years,
and especially from places
like northeastern China,
we've started to get whole
skeletons of dinosaurs,
sometimes with residues
of feathers or skin
or things like that.
And naturally, the more
we've got of a fossil animal
the more we can learn about it.
So the better our,
I often joke that
invertebrate paleontology,
whoever has the best toys wins.
And that's--
(laughing)
And you know, with the
fossils being the toys.
And I've definitely worked on
extremely poorly
represented fossils before,
but I've also had the pleasure to work on
some really extraordinary fossils, too.
And naturally, we can say a lot more about
the really complete ones than we can
about the really fragmentary ones.
- So what would be the
minimum number of bones
or fragments you would
need to actually describe
something as new?
- Another good question.
The standard has increased with time.
There was a, back in the
day people would name
new dinosaur species based on
isolated teeth, for instance.
As you can imagine, especially
in the case of dinosaurs,
that where their teeth are
relatively homogeneous,
relatively, they relatively
all look the same,
compared to mammals, for instance,
you can imagine that
this has led to a lot of
taxonomic problems later
in history as features
that were once unique to
that, quote, unquote, species
have been found to characterize
lots of different things.
And so what remains true throughout time
is that the species, the fossil species
that are named on the best material
are most likely to last,
to stand the test of time.
But in terms of a minimum number,
there really isn't one.
Once in a while somebody will still name,
say, a new dinosaur on the basis
of a single tooth or something like that.
- Okay.
- Yeah, it's,
but the ideal is much more than that.
Like a significant part of a skeleton
or a skull or something that,
the bottom line is it has to
show what we call autapomorphy,
is on other words, unique derived features
that nothing else has.
And once in a while you'll
find a really bizarre jaw
or hind limb or something like that
that shows features that nothing else has.
And at least according to
the current state of the art
in dinosaur paleontology
you would be justified
in naming something based on that.
But long story short, the
more you have the better.
- Okay, so let's see your replica
or whatever you have there.
- Oh yeah, yeah.
So I have my camera off.
So you'll have to tell me
if I've got it in view.
- Is that a claw?
(voice muffled)
- Yeah, this is a claw.
- No.
- Yeah, yeah, yeah.
- What?
Is that life size?
- Yeah, yeah, yeah.
So here's my hand at the
same size as this for scale.
You can see,
you can see hopefully that it's
broken off at the tip here,
and so it would have extended
quite a bit further in life,
probably something like
this, but remember, too,
this is just the bony core of the claw,
and just like us, just
like humans or your cat
or whatever it might be,
the claw would be covered in keratin,
the same stuff your
fingernails are made of,
so it would have been even longer in life.
Probably the bony part
may be out to about here,
hopefully you can see
that, tell me if you can't,
and then maybe with
keratin maybe out to here,
or something like that.
So you're talking about an
animal that was wielding on its,
and this claw goes on the thumb,
an animal that was
wielding claws that were
probably 15 inches long
when this thing was alive.
In other words,
it can mess you up really bad.
- So how big
does that make the animal?
- Well so, it's interesting,
that's the next logical question.
But these animals are really interesting
because they seem to have
outlandishly humongous claws
on the first and second digits,
the first and second fingers,
of the hand, the forefoot.
So that's the claw that goes on the thumb,
what we would call digit one,
'cause we count from the
inside to the outside.
And the claw on digit
two is almost as big.
So it would look like the
thing was running with scissors
or something like that,
with two giant blades on
its first two fingers.
But what's really crazy is these guys,
these animals have,
they're three fingered,
like T-Rex is famously two fingered,
megaraptorids are three fingered,
we know that for sure,
because we have complete
hands of megaraptorids.
And the third finger actually
carries a much smaller claw.
So in this animal here,
we have the third claw,
the claw that goes on the third digit,
and it's only about this long.
So, I don't know if you can tell, but I,
this is roughly maybe three inches long
or something like that.
So you've got this massive
15-inch claw on the thumb,
a claw that's almost as
big on the second finger,
and then, and then this little kinda
rinky-dink claw on the third finger.
There's actually some evidence--
- How many fingers do you
go from the inside out?
- Yes, yeah, so thumb is number one,
pointer finger's number two,
middle finger's number three,
and so in a dinosaur, of
course, because most of 'em,
most predatory dinosaurs
have three fingers,
it's actually our pointer finger
is the middle finger in a dinosaur.
But if,
in all vertebrates, in all
animals, all vertebrate animals,
all tetrapods at least, you
count inside to outside.
So thumb is one, pointer finger's two,
middle finger's three, ring
finger four, and pinky five.
- And are these bipedal
or are the quadrupeds?
- No these were undoubtedly
bipedal for sure.
And so just to answer your question,
which I didn't really answer before,
these are big animals but not giant.
You would expect that
with a claw like that
that if you scale that up
from a T-Rex or something
you're looking at a meat eating dinosaur
that's probably 70 feet long.
But as it turns out they
don't scale that way.
They have proportionately
giant hands and giant claws,
and so the animal to
which this claw pertained
was likely about maybe 20 to 25 feet long.
So big as a predatory
dinosaur goes, but not giant.
A T-Rex, by comparison,
can be 42 feet long.
- What about compared to,
I'm trying to think of like,
at that size I don't have a good,
this is gonna show my (voice muffled)
tell it to me in meters
and then tell it to me
in relation to a (voice muffled) animal.
- Sure, so in meters it'd be
maybe seven to eight meters long,
and in terms of,
yeah, but you're talking like, again,
a T-Rex can be 12 to 13 meters long.
So these are gigantic animals.
The big predatory dinosaurs are.
In terms of mass a megaraptorid would be
bigger than a polar bear for sure,
but yeah, so these are
big formidable animals,
but I guess my point is,
even as big and formidable as they are
they were not giant as
predatory dinosaurs go.
There are lots and lots of different kinds
that were way bigger.
T-Rex, a group called carcharodontosaurids
that were probably the mass of
one or two elephants put together.
Another group called
spinosaurids, which got humongous
and strangely have aquatic adaptations.
They seem to have spent a
lot of their time in water,
which is really cool.
