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Paleontology,

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a science geared towards small children.

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Focused on digging up dinosaurs

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while sporting a "Jurassic Park" costume.

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Skulls are popped out of the ground

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and put on display for public gawking.

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The relevance of this, beyond clickbait,
coloring books and monster movies,

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is unknown.

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No ...

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Wait.

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That's not paleontology at all.

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Paleontology is nothing less
than the study of past life.

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All past life.

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From ancestors to alien forms.

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It involves fundamental questions
like "who are we,"

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and "how did we get here,"

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using the broadest possible
definition of "we" --

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life itself.

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Dinosaurs, a category of birds,

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are just a small percentage of that.

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(Laughter)

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Yet they get the most media attention.

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[The incredible diversity of ancient life,
Dinosaurs, Paleontology]

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It's a very accurate meme;
I didn't even make this one.

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This is just the truth.

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Anyway, most of us paleontologists
consider dinosaurs to be a gateway drug.

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There is so much cooler stuff
in the fossil record,

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and we know so much about it.

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Let's go on a brief, dinosaur-free tour

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of the last four billion years.

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(Laughter)

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First up, genetic material.

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Viruses, basically,
started producing proteins

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and wrecking their environment.

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The Earth was infected with life.

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Some of these new bacteria
learned how to eat sunshine,

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producing oxygen,

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pulling carbon from the air,

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and destroying the iron food
of other microbes,

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by turning it into rust.

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This went on for billions of years.

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Some bacteria consumed other bacteria,

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gaining their power
to turn oxygen into energy,

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becoming the precursors
of animals and plants.

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But as a result,
there were climate shocks,

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from hot to cold and back again,

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which ended up turning the Earth
into a snowball covered with glaciers.

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The technical term for this time period
is "Snowball Earth."

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(Laughter)

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Seven hundred, eight hundred
million years ago.

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Anyway, microbes banded together,

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creating multicellular life.

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Six hundred million years ago,

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geometric colonies appeared,
sucking microbes from the water.

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These were soon replaced
by the ancestors of modern animals.

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The Cambrian explosion.

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Lobster relatives ate other animals,

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capturing them using their grasping arms.

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Armored wriggling clam worms
crawled across the seafloor and into it,

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creating new ecosystems.

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Our tadpole-like ancestors
flitted along ancient coastlines,

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while their eel-like relatives
with gnashing throat teeth

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swam above the ice-cream cone corals
of the first reefs,

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dodging school-bus-sized krakens

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and hungry sea scorpions.

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Plant fungus came onto land.

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But then the glaciers returned,
killing pretty much everything.

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But mass extinctions open opportunities.

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Jawless fishes invaded the ocean,

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sporting points, prongs,
and finally, fins.

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Spiders, scorpions, snails
and worms came onto land.

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Somewhere around China,
a fish developed jaws,

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and its descendants drove jawless fishes,

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sea scorpions and branching plankton

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to extinction.

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Some of these fishes,

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which had arm bones in their fins,

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sprouted fingers,

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seven or eight per flipper.

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On land, plants became trees,

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growing massive

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or spreading their spores
only once before dying.

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But then the glaciers came back again

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and it was mass extinction number two.

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It was the age of weird fishes
and plated sea lilies.

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Sharks with wings.

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Sharks with buzz saw jaws.

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Sharks with fins covered in tiny teeth.

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Sharks with crushing tooth plates.

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Bony fishes that looked like
modern angelfish and eels

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for the first time.

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Wetlands developed,

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sporting ten-foot-long millipedes
and giant dragon flies.

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These spread across the supercontinent
of Pangaea and died,

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creating coal,

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leading to a 100-million-year Ice Age.

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Finally, vertebrates made it onto land
on a permanent basis,

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leading to alligator-like amphibians

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and saber-toothed protomammals.

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But then, volcanoes erupted
all over Siberia,

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everything almost died,

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and it was mass extinction number three.

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(Laughter)

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The day life nearly died.

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A single, lonely tusked mammal
survived and thrived,

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but it was soon replaced
by galloping crocodiles.

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In the ocean, marine reptiles,

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giant rafts made of the living
relatives of sea urchins,

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and armored squids, ammonoids
of every kind and form.

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But then, Pangaea started to split apart,

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forming a sea of lava

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that would one day become
the Atlantic Ocean,

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spewing toxic gas into the atmosphere

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and mass extinction number four.

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(Laughter)

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Yeah, there's actually
a lot more than these five,

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these are the big ones.

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(Laughter)

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So, finally, there were
whale-sized fishes,

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and modern fishes mobbed corals,

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made gigantic by using
their captured algae to eat sunshine.

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Crabs, stingrays and other fishes
with crushing teeth appeared,

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smashing shells

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and leading to an arms race
between predators and prey.

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There was an explosion
of marine biodiversity.

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Mammals climbed trees, flew,

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and did a lot of other things
that are seemingly sort of modern.

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They were feeding on the first flowers
pollinated by the first bees.

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There were ecological revolutions
on land and at sea,

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leading to the modern world.

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Except that an asteroid hit Mexico,

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and then that triggered volcanoes
on the other side of the world in India,

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and everything almost died again.

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(Laughter)

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But -- there's always a but,
because we're still here --

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mammals arose from the ashes,

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became small under extreme heat,
and then ever larger.

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There were palm trees
and snakes in the Arctic.

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Predatory deer dogs frolicked
along ancient rivers,

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while their relatives
returned to the ocean

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to become the first otter-like whales.

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Not hyenas and other sort of carnivores

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were chased off by giant
long-necked rhinos.

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Everything at this point
seems kind of familiar,

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but not really.

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In Antarctica, an ice age started,

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forming the first permanent polar ice cap
in two hundred million years.

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This dried out the rest of the world,

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but it allowed the rise of grasses,
of rodents, of cats.

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Somewhere in Africa,

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an ape started walking
across the new savannah.

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Oh, and there were giant
saber-toothed salmon,

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I just have to mention that.

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(Laughter)

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So, we know all of this happened,

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and so much more.

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How?

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Why?

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Paleontology is a thriving science

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at the intersection of multiple
other fields and technologies.

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There is no bigger data
than the fossil record,

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and we mine every bit of it.

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We use CAT scans,

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we use isotopes,

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we use genomes,

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we use robots,

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we use mathematical simulations,

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and all kinds of analytics.

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We maximize all of it
so that we can understand the past,

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and how evolution works.

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It also lets us make
predictions for the future.

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What will happen after the next
mass extinction?

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What weird things will show up?

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Will mammals get smaller again?

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Will there even be mammals?

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In sum,

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we have learned a lot about dinosaurs.

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But there's so much left to learn

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from the other 99.9 percent of things
that have ever lived.

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And that's paleontology.

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Thank you.

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(Applause and cheers)