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  • Imagine being a fossil:

  • touring the world's great museums,

  • inspiring awe in onlookers of all ages,

  • posing for hordes of fawning photographers.

  • Sound like something you'd like?

  • Well, good luck!

  • At least 99.9% of creatures that have ever lived

  • aren't preserved in the fossil record.

  • But forget about them,

  • everyone else will,

  • and listen up!

  • If you want your corpse

  • in the exclusive 0.01% Club,

  • the Hall of Preserved Fossil Fame,

  • it will not be easy.

  • You better work!

  • Step one: die.

  • It's a cold, hard fact of fossilization.

  • Everything paleontologists find

  • was once alive and, at some point, died.

  • We'll skip the details

  • and assume you had a long, fulfilling life

  • so we can get to what is really important --

  • how you die.

  • There are many ways to become a fossil,

  • so let's highlight your top death options.

  • You could get yourself trapped in tree sap,

  • which, when hardens, turns into amber

  • and can survive intact for millions of years.

  • But unless you find a really big tree to sit under,

  • amber preservation will likely remain

  • the domain of insects and other very small animals.

  • Generally, the right place to be

  • if you want to end up a fossil

  • is wherever sediment is actively being deposited,

  • like a lake or an ocean floor.

  • A mountaintop or prairie?

  • Not good!

  • You need to get buried,

  • the faster the better,

  • because the longer you hang around on the surface,

  • the more likely you'll get eaten,

  • scavenged,

  • or otherwise destroyed

  • before ever having a chance to get preserved.

  • If you can get buried someplace

  • with little to no oxygen,

  • like a bog or a deep lake bottom,

  • even better.

  • That lack of oxygen will slow down your decay

  • and give you more time to fossilize.

  • So, let's say you're lucky enough to die

  • and get buried in a shallow sea

  • under muddy, sandy sediments.

  • What's your next move?

  • One option is a process

  • called permineralization.

  • While all your soft parts decay away,

  • your bones get saturated with mineral-rich waters.

  • Bit by bit, microscopic crystals precipitate

  • out of these waters

  • to fill in the empty spaces and pores in your bones.

  • Otherwise, you'd better hope

  • the sediments around you harden

  • while your bones decay away

  • and another sediment or mineral fills in the spaces

  • your bones leave behind,

  • creating a perfect cast of your skeleton.

  • Over time, the sediments around your fossil

  • will lithify or turn into rock.

  • But you're not in the clear yet!

  • Many things could happen

  • to those sedimentary rocks

  • that might destroy your chances

  • of getting discovered.

  • They could get uplifted into a mountain range

  • and eroded away

  • or carried along in an oceanic plate

  • and subducted back into the Earth's mantle,

  • melting your fossil into hot mush.

  • Fingers crossed your rock surroundings

  • will get gently lifted up

  • by plate tectonics,

  • sea levels will change,

  • and you'll end up under dry land

  • close to the surface,

  • but not so close

  • that erosion from wind and rain wipes you away

  • before someone can come find you.

  • The last step in this long process,

  • an intrepid paleontologist has to come find you.

  • Maybe she's a research scientist

  • scouting for fossils your age and type

  • or just an amateur collector

  • hoping for a fortuitous find.

  • She whacks away at layers of rock above you

  • or spots your fossil exposed

  • in a creek bank after a flood.

  • And there you are,

  • a magnificent scientific discovery,

  • millions of years in the making!

  • She and her colleagues gently extract you

  • from the surrounding sediment,

  • measure and photograph

  • all the bits and pieces they find,

  • and begin the complex task of reconstructing

  • how and when you lived

  • based on the evidence they find in your bones.

  • Paleontologists will be some of your biggest fans

  • along with all those admiring crowds at the museum.

  • You made it!

  • You spent years underground in obscurity,

  • shedding blood,

  • sweat,

  • tears,

  • and your internal organs.

  • You worked yourself to the bone

  • until your bones disintegrated

  • and were replaced by minerals and sediments.

  • But it was all worth it

  • because you're a famous fossil!

  • Now, you better hold that pose!

Imagine being a fossil:

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TED-ED】どうやって化石化するのか...自分自身 - Phoebe A. Cohen (【TED-Ed】How to fossilize...yourself - Phoebe A. Cohen)

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    keep seeing に公開 2021 年 01 月 14 日
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