WEBVTT

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So this is a story

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about how we know what we know.

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It's a story about this woman,

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Natalia Rybczynski.

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She's a paleobiologist,

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which means she specializes
in digging up really old dead stuff.

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(Audio) Natalia Rybczynski: Yeah,
I had someone who called me

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Dr. Dead Things.

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Latif Nasser: And I think she's
particularly interesting

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because of where she digs that stuff up,

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way above the Arctic Circle
in the remote Canadian tundra.

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Now, one summer day in 2006,

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she was at a dig site called
the Fyles Leaf Bed,

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which is less than 10 degrees latitude
away from the magnetic north pole.

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(Audio) NR: Really, like, it's not going
to sound very exciting,

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because it was a day of walking
with your backpack and your GPS

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and notebook and just picking up
anything that might be a fossil.

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LN: And at some point,
she noticed something.

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(Audio) NR: Rusty, kind of rust-colored,

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about the size of the palm of my hand.

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It was just lying on the surface.

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LN: And at first she thought
it was just a splinter of wood,

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because that's the sort of thing
people had found

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at the Fyles Leaf Bed before,
prehistoric plant parts.

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But that night, back at camp...

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(Audio) NR: When I get out the hand lens,

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I'm looking a little bit
more closely and realizing

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it doesn't quite look like
this has tree rings.

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Maybe it's a preservation thing,

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but it looks really like bone.

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LN: Huh. So over the next four years,

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she went to that spot over and over,

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and eventually collected 30 fragments
of that exact same bone,

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most of them really tiny.

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(Audio) NR: It's not a whole lot.
It fits in a small Ziploc bag.

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LN: And she tried to piece them together
like a jigsaw puzzle,

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but it was challenging.

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(Audio) NR: Because it's broken up
into so many little tiny pieces,

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I'm trying to use sand and putty,

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and it's not looking good,

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so finally we had a 3D surface scanner.

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LN: Ooh!
NR: Yeah, right?

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(Laughter)

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LN: It turns out it was way easier
to do it virtually.

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(Audio) NR: It's kind of magical
when it all fits together.

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LN: How certain were you
that you had it right,

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that you had put it together
in the right way?

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Was there a potential that you
put it together a different way

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and you had, like,
a parakeet or something?

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(Audio) NR: (Laughs) Umm, no.
No, we got this.

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LN: What she had, she discovered,
was a tibia, a leg bone,

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and specifically one that belonged
to a cloven-hoofed mammal,

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so something like a cow or a sheep,

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but it couldn't have been either of those.

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It was just too big.

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(Audio) NR: The size of this thing,
it was huge. It's a really big animal.

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LN: So what animal could it be?

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Having hit a wall, she showed
one of the fragments

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to some colleagues of hers in Colorado,

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and they had an idea.

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(Audio) NR: We took a saw,
and we nicked just the edge of it,

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and there was this really interesting
smell that comes from it.

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LN: It smelled kind of like singed flesh.

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It was a smell that Natalia recognized
from cutting up skulls

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in her gross anatomy lab: collagen.

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Collagen is what gives
structure to our bones.

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And usually, after so many years,

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it breaks down.

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But in this case, the Arctic had acted
like a natural freezer and preserved it.

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Then a year or two later,

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Natalia was at a conference in Bristol,

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and she saw that a colleague of hers
named Mike Buckley

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was demoing this new process
that he called collagen fingerprinting.

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It turns out that different species
have slightly different structures

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of collagen, so if you get a collagen
profile of an unknown bone,

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you can compare it
to those of known species,

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and who knows, maybe you get a match.

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So she shipped him one of the fragments,

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FedEx.

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(Audio) NR: Yeah, you want to track it.
It's kind of important.

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(Laughter)

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LN: And he processed it, and compared it

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to 37 known and modern day mammal species.

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And he found a match.

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It turns out that
the 3.5 million-year old bone

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that Natalia had dug
out of the high Arctic

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belonged to...

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a camel.

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(Laughter)

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(Audio) NR: And I'm thinking, what?
That's amazing. If it's true.

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LN: So they tested
a bunch of the fragments,

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and they got the same result for each one.

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However, based on the size
of the bone that they found

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was such that it meant that this camel

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was 30 percent larger
than modern day camels.

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So this camel would have been
about nine feet tall,

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weighed around a ton.

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Yeah.

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Natalia had found a giant Arctic camel.

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(Laughter)

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Now, when you hear the word camel,

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what may come to mind is one of these,

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the Bactrian camel
of East and Central Asia.

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But chances are the postcard image
you have in your brain

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is one of these, the dromedary,

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quintessential desert creature --

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hangs out in sandy hot places
like the Middle East and the Sahara,

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has a big old hump on its back
for storing water

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for those long desert treks,

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has big, broad feet to help it
tromp over sand dunes.

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So how on earth would one of these guys

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end up in the High Arctic?

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Well, scientists have known
for a long time, turns out,

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even before Natalia's discovery,

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that camels are actually
originally American.

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(Music: The Star Spangled Banner)

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(Laughter)

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They started here.

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For nearly 40 of the 45 million years
that camels have been around,

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you could only find them in North America,

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around 20 different species, maybe more.

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(Audio) LN: If I put them all in a lineup,
would they look different?

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NR: Yeah, so you're going
to have different body sizes.

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You're going to have some
with really long necks,

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so they're actually
functionally like giraffes.

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LN: Some had snouts, like crocodiles.

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(Audio) NR: The really primitive,
early ones would have been really small,

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almost like rabbits.

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LN: What? Rabbit-sized camels?

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(Audio) NR: The earliest ones.

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And so those ones you probably
would not recognize. Yeah.

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LN: Oh my God, I want a pet rabbit-camel.

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(Audio) NR: I know,
wouldn't that be great?

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LN: And then about three
to seven million years ago,

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one branch of camels
went down to South America,

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where they became llamas and alpacas,

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and another branch crossed over
the Bering Land Bridge

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into Asia and Africa.

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And then around the end
of the last ice age,

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North American camels went extinct.

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So scientists knew all of that already,

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but it still doesn't fully explain
how Natalia found one so far north.

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Like, this is, temperature-wise,
the polar opposite of the Sahara.

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Now, to be fair,

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three and half million years ago,
it was on average

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22 degrees Celsius warmer than it is now.

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So it would have been boreal forest,

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so more like the Yukon or Siberia today.

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But still, like, they would have
six-month-long winters

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where the ponds would freeze over.

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You'd have blizzards.

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You'd have 24 hours a day
of straight darkness.

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Like, how? How?

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How is it that one of these
Saharan superstars

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ever have survived
those arctic conditions?

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(Laughter)

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Natalia and her colleagues
think they have an answer,

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and it's kind of brilliant.

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What if the very features that we imagine

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make the camel so well-suited
to places like the Sahara

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actually evolved to help it
get through the winter?

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What if those broad feet were meant
to tromp not over sand

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but over snow, like a pair of snowshoes?

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What if that hump --
which, huge news to me,

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does not contain water, it contains fat --

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(Laughter)

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was there to help the camel
get through that six-month-long winter,

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when food was scarce?

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And then, only later, long after
it crossed over the land bridge

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did it retrofit those winter features
for a hot desert environment?

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Like, for instance, the hump
may be helpful to camels in hotter climes

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because having all your fat in one place,

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like a, you know, fat backpack,

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means that you don't have
to have that insulation

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all over the rest of your body.

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So it helps heat dissipate easier.

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It's this crazy idea,

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that what seems like proof of the camel's
quintessential desert nature

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could actually be proof
of its High Arctic past.

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Now, I'm not the first person
to tell this story.

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Others have told it as a way
to marvel at evolutionary biology

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or as a keyhole into the future
of climate change.

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But I love it for a totally
different reason.

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For me, it's a story about us,

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about how we see the world

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and about how that changes.

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So I was trained as a historian.

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And I've learned that actually
a lot of scientists are historians, too.

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They make sense of the past.

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They tell the history of our universe,
of our planet, of life on this planet.

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And as a historian, you start
with an idea in your mind

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of how the story goes.

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(Audio) NR: We make up stories,
and we stick with it,

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like the camel in the desert, right?

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That's a great story!
It's totally adapted for that.

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Clearly, it always lived there.

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LN: But at any moment, you could
uncover some tiny bit of evidence.

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You could learn some tiny thing

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that forces you to reframe
everything you thought you knew.

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Like, in this case, this one scientist
finds this one shard

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of what she thought was wood,

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and because of that, science has a totally
new and totally counterintuitive theory

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about why this absurd,
Dr. Seuss-looking creature

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looks the way it does.

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And, for me, it completely upended
the way I think of the camel.

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It went from being
this ridiculously niche creature

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suited only to this
one specific environment,

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to being this world traveler

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that just happens to be in the Sahara

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and could end up virtually anywhere.

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(Applause)

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This is Azuri.

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Azuri, hi, how are you doing?

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OK, here, I've got
one of these for you here.

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So Azuri is on a break
from her regular gig

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at the Radio City Music Hall.

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(Laughter)

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That's not even a joke.

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Anyway --

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But really, Azuri is here
as a living reminder

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that the story of our world

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is a dynamic one.

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It requires our willingness
to readjust, to reimagine.

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(Laughter)

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Right, Azuri?

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And really that we're all
just one shard of bone away

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from seeing the world anew.

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Thank you very much.

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(Applause)