Name: 【TED】Karen Lloyd: This deep-sea mystery is changing our understanding of life (This deep-sea mystery is changing our understanding of life | Karen Lloyd)
Uploaded: 2018-03-01T04:36:44.000Z
Duration: 13 min 9 s
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I'm an ocean microbiologist at the University of Tennessee,

and I want to tell you guys about some microbes

Adverbs of degree

that they're challenging our assumptions about what life is like on Earth.

Please raise your hand if you've ever thought it would be cool

to go to the bottom of the ocean in a submarine?

Most of you, because the oceans are so cool.

if the reason you raised your hand to go to the bottom of the ocean

is because it would get you a little bit closer

trying to determine how deep we can go into the Earth

and still find something, anything, that's alive,

because we still don't know the answer to this very basic question

So in the 1980s, a scientist named John Parkes, in the UK,

He believed that there was a vast, deep, and living microbial biosphere

that extends hundreds of meters into the seafloor,

but the only problem is that nobody believed him,

is that ocean sediments may be the most boring place on Earth.

there's no fresh food deliveries for literally millions of years.

to know that that is a bad place to go looking for life.

But in 2002, [Steven D'Hondt] had convinced enough people

that he was on to something  that he actually got an expedition

on this drillship, called the JOIDES Resolution.

And he ran it along with Bo Barker Jørgensen of Denmark.

some really without contamination from surface microbes.

This drill ship is capable of drilling thousands of meters underneath the ocean,

and the mud comes up in sequential cores, one after the other --

This is being carried by scientists such as myself who go on these ships,

and we process the cores on the ships and then we send them home

to our home laboratories for further study.

got these first precious deep-sea pristine samples,

and they saw images that looked pretty much like this,

which is actually taken from a more recent expedition

You can see the hazy stuff in the background.

and the bright green dots stained with the green fluorescent dye

Now I've got to tell you something really tragic about microbes.

They all look the same under a microscope,

You can take the most fascinating organisms in the world,

like a microbe that literally breathes uranium,

So we can't use their looks to tell them apart.

And I'll teach you guys how to do it right now.

So I made up some data, and I'm going to show you some data that are not real.

This is to illustrate what it would look like

if a bunch of species were not related to each other at all.

has a list of combinations of A, G, C and T,

sort of randomly jumbled, and nothing looks like anything else,

and these species are totally unrelated to each other.

from a gene that these species happen to share.

The chances of getting so many of those vertical columns

where every species has a C or every species has a T,

So we know that all those species had to have had a common ancestor.

which y'all already knew were related, because, I mean, obviously.

But we're also related to things that we don't look like,

like pine trees and Giardia, which is that gastrointestinal disease

you can get if you don't filter your water while you're hiking.

We're also related to bacteria like E. coli and Clostridium difficile,

【TED】Karen Lloyd: This deep-sea mystery is changing our understanding of life (This deep-sea mystery is changing our understanding of life | Karen Lloyd)

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【TED】Karen Lloyd: This deep-sea mystery is changing our understanding of life (This deep-sea mystery is changing our understanding of life | Karen Lloyd)

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bacteria