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Hunting for dinosaurs showed me our place in the universe
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0:01 - 0:03How do you find a dinosaur?
-
0:04 - 0:06Sounds impossible, doesn't it?
-
0:07 - 0:08It's not.
-
0:08 - 0:12And the answer relies on a formula
that all paleontologists use. -
0:13 - 0:15And I'm going to tell you the secret.
-
0:15 - 0:18First, find rocks of the right age.
-
0:19 - 0:23Second, those rocks
must be sedimentary rocks. -
0:24 - 0:28And third, layers of those rocks
must be naturally exposed. -
0:29 - 0:30That's it.
-
0:30 - 0:33Find those three things
and get yourself on the ground, -
0:33 - 0:36chances are good
that you will find fossils. -
0:36 - 0:38Now let me break down this formula.
-
0:39 - 0:43Organisms exist only during certain
geological intervals, -
0:43 - 0:46so you have to find
rocks of the right age, -
0:46 - 0:48depending on what your interests are.
-
0:48 - 0:49If you want to find trilobites,
-
0:49 - 0:53you have to find the really,
really old rocks of the Paleozoic -- -
0:53 - 0:56rocks between a half a billion
and a quarter-billion years old. -
0:56 - 0:58Now, if you want to find dinosaurs,
-
0:58 - 1:01don't look in the Paleozoic,
you won't find them. -
1:01 - 1:02They hadn't evolved yet.
-
1:02 - 1:05You have to find the younger
rocks of the Mesozoic, -
1:05 - 1:07and in the case of dinosaurs,
-
1:07 - 1:11between 235 and 66 million years ago.
-
1:11 - 1:15Now, it's fairly easy to find rocks
of the right age at this point, -
1:15 - 1:18because the Earth is, to a coarse degree,
-
1:18 - 1:19geologically mapped.
-
1:20 - 1:22This is hard-won information.
-
1:22 - 1:25The annals of Earth history
are written in rocks, -
1:25 - 1:26one chapter upon the next,
-
1:26 - 1:29such that the oldest pages are on bottom
-
1:29 - 1:31and the youngest on top.
-
1:32 - 1:36Now, were it quite that easy,
geologists would rejoice. -
1:36 - 1:37It's not.
-
1:37 - 1:39The library of Earth is an old one.
-
1:39 - 1:42It has no librarian to impose order.
-
1:42 - 1:45Operating over vast swaths of time,
-
1:45 - 1:49myriad geological processes
offer every possible insult -
1:50 - 1:52to the rocks of ages.
-
1:52 - 1:55Most pages are destroyed
soon after being written. -
1:55 - 1:57Some pages are overwritten,
-
1:57 - 2:02creating difficult-to-decipher palimpsests
of long-gone landscapes. -
2:02 - 2:07Pages that do find sanctuary
under the advancing sands of time -
2:07 - 2:09are never truly safe.
-
2:09 - 2:13Unlike the Moon --
our dead, rocky companion, -
2:13 - 2:16the Earth is alive, pulsing
with creative and destructive forces -
2:16 - 2:19that power its geological metabolism.
-
2:20 - 2:22Lunar rocks brought back
by the Apollo astronauts -
2:22 - 2:25all date back to about the age
of the Solar System. -
2:26 - 2:28Moon rocks are forever.
-
2:29 - 2:33Earth rocks, on the other hand,
face the perils of a living lithosphere. -
2:33 - 2:35All will suffer ruination,
-
2:35 - 2:38through some combination
of mutilation, compression, -
2:38 - 2:40folding, tearing, scorching and baking.
-
2:41 - 2:46Thus, the volumes of Earth history
are incomplete and disheveled. -
2:47 - 2:51The library is vast and magnificent --
-
2:52 - 2:53but decrepit.
-
2:54 - 2:57And it was this tattered complexity
in the rock record -
2:57 - 3:00that obscured its meaning
until relatively recently. -
3:01 - 3:03Nature provided no card catalog
for geologists -- -
3:03 - 3:05this would have to be invented.
-
3:06 - 3:10Five thousand years after the Sumerians
learned to record their thoughts -
3:10 - 3:11on clay tablets,
-
3:11 - 3:14the Earth's volumes remained
inscrutable to humans. -
3:14 - 3:17We were geologically illiterate,
-
3:18 - 3:21unaware of the antiquity
of our own planet, -
3:21 - 3:22and ignorant of our connection
-
3:22 - 3:24to deep time.
-
3:25 - 3:28It wasn't until the turn
of the 19th century -
3:28 - 3:31that our blinders were removed,
-
3:31 - 3:35first, with the publication
of James Hutton's "Theory of the Earth," -
3:35 - 3:39in which he told us that the Earth
reveals no vestige of a beginning -
3:39 - 3:41and no prospect of an end;
-
3:42 - 3:45and then, with the printing
of William Smith's map of Britain, -
3:46 - 3:48the first country-scale geological map,
-
3:48 - 3:49giving us for the first time
-
3:49 - 3:53predictive insight into where
certain types of rocks might occur. -
3:54 - 3:56After that, you could say things like,
-
3:56 - 3:59"If we go over there,
we should be in the Jurassic," -
3:59 - 4:02or, "If we go up over that hill,
we should find the Cretaceous." -
4:03 - 4:06So now, if you want to find trilobites,
-
4:06 - 4:08get yourself a good geological map
-
4:08 - 4:10and go to the rocks of the Paleozoic.
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4:11 - 4:13If you want to find dinosaurs like I do,
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4:13 - 4:16find the rocks of Mesozoic and go there.
-
4:17 - 4:20Now of course, you can only make
a fossil in a sedimentary rock, -
4:20 - 4:22a rock made by sand and mud.
-
4:22 - 4:24You can't have a fossil
-
4:24 - 4:27in an igneous rock formed
by magma, like a granite, -
4:27 - 4:30or in a metamorphic rock
that's been heated and squeezed. -
4:31 - 4:33And you have to get yourself in a desert.
-
4:33 - 4:36It's not that dinosaurs
particularly lived in deserts; -
4:36 - 4:38they lived on every land mass
-
4:38 - 4:40and in every imaginable environment.
-
4:41 - 4:44It's that you need to go to a place
that's a desert today, -
4:44 - 4:47a place that doesn't have
too many plants covering up the rocks, -
4:47 - 4:51and a place where erosion is always
exposing new bones at the surface. -
4:51 - 4:53So find those three things:
-
4:53 - 4:54rocks of the right age,
-
4:54 - 4:57sedimentary rocks, in a desert,
-
4:58 - 4:59and get yourself on the ground,
-
4:59 - 5:01and you literally walk
-
5:01 - 5:03until you see a bone
sticking out of the rock. -
5:05 - 5:08Here's a picture that I took
in Southern Patagonia. -
5:08 - 5:11Every pebble that you see
on the ground there -
5:11 - 5:13is a piece of dinosaur bone.
-
5:13 - 5:15So when you're in that right situation,
-
5:15 - 5:18it's not a question of whether
you'll find fossils or not; -
5:18 - 5:20you're going to find fossils.
-
5:20 - 5:24The question is: will you find something
that is scientifically significant? -
5:24 - 5:28And to help with that, I'm going to add
a fourth part to our formula, -
5:28 - 5:29which is this:
-
5:29 - 5:33get as far away from other
paleontologists as possible. -
5:33 - 5:35(Laughter)
-
5:35 - 5:37It's not that I don't like
other paleontologists. -
5:37 - 5:40When you go to a place
that's relatively unexplored, -
5:40 - 5:43you have a much better chance
of not only finding fossils, -
5:43 - 5:45but of finding something
that's new to science. -
5:46 - 5:48So that's my formula
for finding dinosaurs, -
5:48 - 5:50and I've applied it all around the world.
-
5:50 - 5:52In the austral summer of 2004,
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5:52 - 5:54I went to the bottom of South America,
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5:54 - 5:56to the bottom of Patagonia, Argentina,
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5:56 - 5:59to prospect for dinosaurs:
-
5:59 - 6:02a place that had terrestrial
sedimentary rocks of the right age, -
6:02 - 6:03in a desert,
-
6:03 - 6:06a place that had been barely visited
by paleontologists. -
6:07 - 6:08And we found this.
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6:09 - 6:11This is a femur, a thigh bone,
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6:11 - 6:14of a giant, plant-eating dinosaur.
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6:14 - 6:17That bone is 2.2 meters across.
-
6:17 - 6:19That's over seven feet long.
-
6:20 - 6:22Now, unfortunately,
that bone was isolated. -
6:22 - 6:25We dug and dug and dug,
and there wasn't another bone around. -
6:25 - 6:28But it made us hungry to go back
the next year for more. -
6:28 - 6:30And on the first day
of that next field season, -
6:30 - 6:34I found this: another two-meter femur,
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6:34 - 6:35only this time not isolated,
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6:35 - 6:38this time associated with 145 other bones
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6:39 - 6:40of a giant plant eater.
-
6:41 - 6:45And after three more hard,
really brutal field seasons, -
6:45 - 6:47the quarry came to look like this.
-
6:48 - 6:52And there you see the tail
of that great beast wrapping around me. -
6:52 - 6:55The giant that lay in this grave,
the new species of dinosaur, -
6:55 - 6:59we would eventually call
"Dreadnoughtus schrani". -
7:00 - 7:03Dreadnoughtus was 85 feet
from snout to tail. -
7:03 - 7:06It stood two-and-a-half stories
at the shoulder, -
7:06 - 7:10and all fleshed out in life,
it weighed 65 tons. -
7:11 - 7:15People ask me sometimes,
"Was Dreadnoughtus bigger than a T.rex?" -
7:15 - 7:18That's the mass of eight or nine T.rex.
-
7:19 - 7:22Now, one of the really cool things
about being a paleontologist -
7:22 - 7:25is when you find a new species,
you get to name it. -
7:25 - 7:28And I've always thought it a shame
that these giant, plant-eating dinosaurs -
7:28 - 7:33are too often portrayed as passive,
lumbering platters of meat -
7:33 - 7:34on the landscape.
-
7:34 - 7:35(Laughter)
-
7:36 - 7:37They're not.
-
7:37 - 7:40Big herbivores can be surly
and they can be territorial -- -
7:40 - 7:44you do not want to mess with a hippo
or a rhino or a water buffalo. -
7:45 - 7:50The bison in Yellowstone injure
far more people than do the grizzly bears. -
7:50 - 7:55So can you imagine a big bull,
65-ton Dreadnoughtus -
7:55 - 7:57in the breeding season,
-
7:57 - 7:58defending a territory?
-
7:59 - 8:01That animal would have been
incredibly dangerous, -
8:01 - 8:06a menace to all around, and itself
would have had nothing to fear. -
8:07 - 8:09And thus the name, "Dreadnoughtus,"
-
8:09 - 8:10or, "fears nothing".
-
8:12 - 8:13Now, to grow so large,
-
8:13 - 8:16an animal like Dreadnoughtus
would've had to have been -
8:16 - 8:17a model of efficiency.
-
8:17 - 8:21That long neck and long tail help it
radiate heat into the environment, -
8:21 - 8:23passively controlling its temperature.
-
8:23 - 8:27And that long neck also serves
as a super-efficient feeding mechanism. -
8:27 - 8:30Dreadnoughtus could stand
in one place and with that neck, -
8:30 - 8:32clear out a huge envelope of vegetation,
-
8:32 - 8:36taking in tens of thousands of calories
while expending very few. -
8:37 - 8:41And these animals evolved
a bulldog-like wide-gait stance, -
8:41 - 8:43giving them immense stability,
-
8:44 - 8:48because when you're 65 tons,
when you're literally as big as a house, -
8:48 - 8:50the penalty for falling over
-
8:50 - 8:51is death.
-
8:52 - 8:54Yeah, these animals are big and tough,
-
8:54 - 8:55but they won't take a blow like that.
-
8:55 - 8:58Dreadnoughtus falls over,
ribs break and pierce lungs. -
8:58 - 9:00Organs burst.
-
9:00 - 9:01If you're a big 65-ton Dreadnoughtus,
-
9:01 - 9:04you don't get to fall down
in life -- even once. -
9:06 - 9:09Now, after this particular
Dreadnoughtus carcass was buried -
9:09 - 9:14and de-fleshed by a multitude
of bacteria, worms and insects, -
9:14 - 9:16its bones underwent a brief metamorphosis,
-
9:16 - 9:18exchanging molecules with the groundwater
-
9:18 - 9:21and becoming more and more
like the entombing rock. -
9:22 - 9:24As layer upon layer
of sediment accumulated, -
9:24 - 9:27pressure from all sides
weighed in like a stony glove -
9:27 - 9:32whose firm and enduring grip held
each bone in a stabilizing embrace. -
9:34 - 9:35And then came the long ...
-
9:36 - 9:37nothing.
-
9:38 - 9:41Epoch after epoch of sameness,
-
9:41 - 9:43nonevents without number.
-
9:44 - 9:47All the while, the skeleton lay
everlasting and unchanging -
9:47 - 9:49in perfect equilibrium
-
9:49 - 9:51within its rocky grave.
-
9:52 - 9:54Meanwhile, Earth history unfolded above.
-
9:54 - 9:57The dinosaurs would reign
for another 12 million years -
9:57 - 10:01before their hegemony was snuffed out
in a fiery apocalypse. -
10:02 - 10:04The continents drifted. The mammals rose.
-
10:04 - 10:06The Ice Age came.
-
10:07 - 10:09And then, in East Africa,
-
10:09 - 10:15an unpromising species of ape
evolved the odd trick of sentient thought. -
10:16 - 10:19These brainy primates were not
particularly fast or strong. -
10:20 - 10:22But they excelled at covering ground,
-
10:22 - 10:24and in a remarkable diaspora
-
10:24 - 10:27surpassing even the dinosaurs' record
of territorial conquest, -
10:27 - 10:29they dispersed across the planet,
-
10:29 - 10:32ravishing every ecosystem
they encountered, -
10:33 - 10:36along the way, inventing culture
and metalworking and painting -
10:36 - 10:37and dance and music
-
10:38 - 10:39and science
-
10:40 - 10:44and rocket ships that would eventually
take 12 particularly excellent apes -
10:44 - 10:46to the surface of the Moon.
-
10:49 - 10:53With seven billion peripatetic
Homo sapiens on the planet, -
10:53 - 10:54it was perhaps inevitable
-
10:54 - 10:59that one of them would eventually
trod on the grave of the magnificent titan -
10:59 - 11:02buried beneath the badlands
of Southern Patagonia. -
11:03 - 11:04I was that ape.
-
11:05 - 11:08And standing there, alone in the desert,
-
11:09 - 11:10it was not lost on me
-
11:10 - 11:13that the chance of any one individual
entering the fossil record -
11:13 - 11:15is vanishingly small.
-
11:16 - 11:18But the Earth is very, very old.
-
11:18 - 11:22And over vast tracts of time,
the improbable becomes the probable. -
11:22 - 11:25That's the magic of the geological record.
-
11:25 - 11:28Thus, multitudinous creatures
living and dying on an old planet -
11:28 - 11:30leave behind immense numbers of fossils,
-
11:30 - 11:32each one a small miracle,
-
11:33 - 11:35but collectively, inevitable.
-
11:37 - 11:39Sixty-six million years ago,
an asteroid hits the Earth, -
11:40 - 11:42and wipes out the dinosaurs.
-
11:43 - 11:45This easily might not have been.
-
11:45 - 11:48But we only get one history,
and it's the one that we have. -
11:48 - 11:50But this particular reality
was not inevitable. -
11:50 - 11:53The tiniest perturbation
of that asteroid far from Earth -
11:53 - 11:56would have caused it to miss
our planet by a wide margin. -
11:57 - 12:00The pivotal, calamitous day during which
the dinosaurs were wiped out, -
12:00 - 12:03setting the stage
for the modern world as we know it -
12:03 - 12:05didn't have to be.
-
12:05 - 12:07It could've just been another day --
-
12:07 - 12:09a Thursday, perhaps --
-
12:10 - 12:15among the 63 billion days
already enjoyed by the dinosaurs. -
12:15 - 12:17But over geological time,
-
12:17 - 12:20improbable, nearly impossible events
-
12:20 - 12:21do occur.
-
12:21 - 12:24Along the path from our wormy,
Cambrian ancestors -
12:24 - 12:26to primates dressed in suits,
-
12:26 - 12:31innumerable forks in the road
led us to this very particular reality. -
12:32 - 12:36The bones of Dreadnoughtus
lay underground for 77 million years. -
12:37 - 12:38Who could have imagined
-
12:38 - 12:41that a single species of shrew-like mammal
-
12:41 - 12:43living in the cracks of the dinosaur world
-
12:43 - 12:45would evolve into sentient beings
-
12:45 - 12:48capable of characterizing
and understanding -
12:48 - 12:51the very dinosaurs they must have dreaded?
-
12:53 - 12:56I once stood at the head
of the Missouri River -
12:57 - 12:58and bestraddled it.
-
12:59 - 13:01There, it's nothing more
than a gurgle of water -
13:01 - 13:06that issues forth from beneath a rock
in a boulder in a pasture, -
13:06 - 13:08high in the Bitterroot Mountains.
-
13:08 - 13:11The stream next to it
runs a few hundred yards -
13:11 - 13:13and ends in a small pond.
-
13:14 - 13:17Those two streams -- they look identical.
-
13:18 - 13:20But one is an anonymous trickle of water,
-
13:20 - 13:23and the other is the Missouri River.
-
13:24 - 13:27Now go down to the mouth
of the Missouri, near St. Louis, -
13:27 - 13:30and it's pretty obvious
that that river is a big deal. -
13:31 - 13:33But go up into the Bitterroots
and look at the Missouri, -
13:33 - 13:38and human prospection does not
allow us to see it as anything special. -
13:39 - 13:41Now go back to the Cretaceous Period
-
13:41 - 13:43and look at our tiny, fuzzball ancestors.
-
13:43 - 13:45You would never guess
-
13:45 - 13:47that they would amount
to anything special, -
13:47 - 13:49and they probably wouldn't have,
-
13:49 - 13:51were it not for that pesky asteroid.
-
13:52 - 13:55Now, make a thousand more worlds
and a thousand more solar systems -
13:55 - 13:56and let them run.
-
13:57 - 13:59You will never get the same result.
-
13:59 - 14:03No doubt, those worlds would be
both amazing and amazingly improbable, -
14:03 - 14:06but they would not be our world
and they would not have our history. -
14:06 - 14:09There are an infinite number of histories
that we could've had. -
14:09 - 14:12We only get one, and wow,
did we ever get a good one. -
14:12 - 14:14Dinosaurs like Dreadnoughtus were real.
-
14:15 - 14:18Sea monsters like the mosasaur were real.
-
14:19 - 14:23Dragonflies with the wingspan of an eagle
and pill bugs the length of a car -
14:23 - 14:25really existed.
-
14:27 - 14:29Why study the ancient past?
-
14:31 - 14:32Because it gives us perspective
-
14:33 - 14:34and humility.
-
14:35 - 14:38The dinosaurs died in the world's
fifth mass extinction, -
14:38 - 14:42snuffed out in a cosmic accident
through no fault of their own. -
14:43 - 14:47They didn't see it coming,
and they didn't have a choice. -
14:48 - 14:51We, on the other hand, do have a choice.
-
14:52 - 14:56And the nature of the fossil record
tells us that our place on this planet -
14:56 - 14:59is both precarious
and potentially fleeting. -
14:59 - 15:03Right now, our species is propagating
an environmental disaster -
15:03 - 15:07of geological proportions
that is so broad and so severe, -
15:07 - 15:09it can rightly be called
the sixth extinction. -
15:10 - 15:12Only unlike the dinosaurs,
-
15:13 - 15:15we can see it coming.
-
15:15 - 15:17And unlike the dinosaurs,
-
15:18 - 15:19we can do something about it.
-
15:20 - 15:23That choice is ours.
-
15:23 - 15:25Thank you.
-
15:25 - 15:32(Applause)
- Title:
- Hunting for dinosaurs showed me our place in the universe
- Speaker:
- Kenneth Lacovara
- Description:
-
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 15:49
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene approved English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe | ||
Brian Greene edited English subtitles for Hunting for dinosaurs showed me our place in the universe |
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