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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 call me "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, 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: ... 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 ...
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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: It's broken up
into so many little tiny pieces,
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I'm trying to use sand and putty,
and it's not looking good.
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So finally, we used 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'd
put it together a different way
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and have, like, a parakeet or something?
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(Laughter)
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(Audio) NR: (Laughs) Um, 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
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from cutting up skulls
in her gross anatomy lab:
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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,
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,
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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,
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and compared it 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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it meant that this camel 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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(Audience reacts)
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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
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for storing water
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
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, you're going to have
different body sizes.
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You'll 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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So those ones you probably
would not recognize.
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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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(Laughter)
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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 a half million years ago,
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it was on average 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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could 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
make the camel so well-suited
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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,
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you start with an idea in your mind
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
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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(Laughter)
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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
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)