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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)