JINGMAI O'CONNOR: I think at this point,
people know that birds are dinosaurs.
But now, as we get more and more fossils of dinosaurs
closely related to birds, we now realize
that evolution is so much more complex than that.
I guess you could also say, they're just birds.
Yeah, my birds have claws and teeth,
but I don't think I'd be able to come up
with something as cool and as crazy
as these specimens have shown us.
And I think that is such a thrill, such an excitement.
Paleontology is not what it was in the 20th century.
50 years ago, mostly what paleontologists were doing
was digging up bones, drawing them,
comparing them to each other.
I feel like this is different, giving it a name.
It was less a biological science than it
has become in these days.
And it's amazing, because now, we
have all these new ways of studying dinosaurs.
It's no longer just manly men who go to the field and dig.
Now, you have girls like me.
My name is Jingmai O'Connor.
And I'm a vertebrate paleontologist
who specializes in the study of Mesozoic birds
from the Age of Dinosaurs.
I grew up in Pasadena just outside LA.
And I basically never left the nest until I finished my PhD
and went to China.
My mom is the hardest working person I know.
She wasn't a typical Chinese mom who wanted
us to be a doctor or a lawyer.
She wanted us to be scientists.
Not only did she do her PhD with four kids,
which having done a PhD, I know that it's not easy.
We didn't have babysitters.
She would drag us with her into the lab,
and she would set us up in one corner.
Like, I have to do my experiments.
here's some glass and a blow torch.
Knock yourself out.
So I kind of spent the age from 8 to 12 going on field trips
with my mom when she had to go collect samples.
So yeah, I grew up surrounded by science.
And my mom was just such an influential person to me
that I decided to also be a geologist.
And I will admit this was just because I didn't
know what I wanted to do.
And then later, as a geology student,
I discovered paleontology and fell in love.
One of the papers I remember being assigned
was the paper on microraptor.
It has huge wings formed by feathers
on its arms and its legs.
So it's this four-winged dinosaur.
I mean, how cool is that?
And I was, like, wow, there's such crazy fossils coming out
of China.
This would be a way of combining my love of China
and Chinese culture with paleontology,
my new fascination and obsession.
I work at the Institute of Vertebrate Paleontology
and Paleoanthropology of the Chinese Academy of Sciences,
which is in Beijing, and I would say definitely
one of the top 10 places to study paleontology
in the entire world.
So I work on a number of research questions.
First of all, how did birds first
arise within the Dinosauria?
I mean, evolution is like a bush, not really a tree.
It's a bush.
And within that bush, there is one lineage to modern birds.
So we start off with, say, 50 features
that we see in living birds--
the primary flight feathers attaching
to the hand, the reproductive system
and their respiratory system.
They also have a highly modified digestive system.
Some of the features that evolved in the modern avian
lineage also evolved independently
in other Mesozoic birds.
There's all this diversity.
So that will take careful study to really tease out
the differences.
So bird fossils are rare, but in China, you
have just a ton of fossil birds.
In fact, over half of the entire Mesozoic diversity of birds
comes from a single region in China,
mostly in Liaoning Province.
The rocks that yield all the animals that
are part of this major ecosystem are all formed in lakes.
So in lakes, if something falls to the bottom,
it is less likely to be disturbed
and it's definitely going to get buried.
Birds and pterosaurs fall into the lake
and then got slowly buried by the lake sediments.
And it's preserved in full articulation,
which means the hip bone's connected to the leg bone.
And not only do you have the entire skeleton,
but you also have soft tissues very commonly preserved.
So we can really explore any fossil
we have to the utmost of its potential.
When I first look at a new specimen,
you look over for what is unique about that specimen
and how does it fit in with a larger picture of evolution.
Some specimens have something very striking about them
that it just jumps out.
For example, I had a microraptor-- it's actually
kind of an ugly specimen.
The bones are very badly preserved.
But the reason that the specimen is very cool
is because it preserves bird inside the stomach.
So this tells us microraptor caught this bird
and just basically gulped it down whole.
So when we described that first microraptor with the bird
in the stomach, a lot of people said, oh,
so microraptor must also have lived in trees.
But somebody described a microraptor
that had fish remains in the stomach.
And another specimen preserves a lizard in the stomach.
So that kind of threw a wrench into the whole hypothesis
that microraptor was living in trees
and that's how the lineage evolved flight.
But sometimes, if you want to see a small anatomical feature,
you need to look under a microscope.
This was the case with the specimen of Eoconfuciusornis.
This specimen preserved what I thought was ovarian follicles.
So we took a little sample, demineralized it,
stained them with the same chemicals
that we used to stain modern tissues,
and looked at the sample under a microscope.
And what we saw was that they are ovarian follicles.
I was, like, "Yes."
They have all these tiny, tiny little follicles.
And then when they're about to make a clutch,
these follicles will start to deposit yolk
and get big very quickly, just like we see in living birds.
They can form yolk very rapidly.
This is a product of higher metabolic rate.
So we hypothesize that Confuciusornis and kin
had a high metabolic rate.
The ability to grow fast is also a product
of your higher metabolic rate.
So we looked at the bone structure
to see if I was right about my hypothesis.
You see that the bone grew fast, almost like in living birds.
They reach adult size within the first year.
So the data from the soft tissues of the ovary
agreed with the data that we saw from cutting the bones
and looking at the bone tissue.
So that was cool.
Every time I get a specimen that preserved
some weird soft tissue, I'm, like, all right--
this one preserved lungs.
Then we learned everything about bird lungs.
Or this one preserves what I interpret as ovarian follicles.
Now I have to learn everything about the ovary.
And it's just cool how you can't understand
some of the skeletal structures until you see the soft tissue
structures, like feathers.
Here we have a bird called Jeholornis prima, which lived
about 120 million years ago.
And actually, this is my favorite early Cretaceous bird.
Now, the most challenging thing about this specimen
is that it has this extremely elongate tail.
And this is weird, because all living birds, the bony part
of the tail is very short.
We would expect evolution to be moving in that direction.
And, I thought, it has feathers along the entire length
of the tail.
So it also would have created drag,
meaning it would resist your ability to fly.
It was one of these weird mysteries of avian evolution
until we identified eight specimens that
preserved the feathers.
We actually found that the tail feathers had been reduced.
So you no longer had feathers along the entire length
of the tail.
You only had feathers in two patches.
It doesn't look like it has a lot of aerodynamic properties.
However, if you make the tail longer,
you're actually making the tail more effective as a stabilizer
during flight.
So the elongated tail in Jeholornis
actually allowed it to fly better.
We just couldn't tell that until we had soft tissue preserved.
For a long time, we were trying to fit
everything that flew into one evolutionary path
towards modern birds.
Now, we actually know that flight
evolved within dinosaurs at least three times,
maybe even four times.
So it's a very complicated evolutionary picture.
And this is just something that we've
learned within the last decade.
So maybe 10 years from now, it's going
to be, like, oh, flight evolved in dinosaurs 10 times.
Who knows?
But in terms of the evolutionary story of birds themselves,
I find it so fascinating how this simple process
of natural selection could produce
the incredible diversity that we see today.
That's insane.
It's mind blowing.
My mom, she said every generation
needs to be better than the one before it.
And so every paper I work on, every specimen, you're
really focusing on some tiny, little puzzle piece
that then, other later generations have that knowledge
at their fingertips.
And that's why paleontology is so exciting, because 100
years from now, paleontologists will still
be having exciting new stuff to work on.
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