Penny Chisholm: The tiny creature that secretly powers the planet
佩妮 · 奇斯霍姆: 秘密为地球提供动力的微小生物
Penny Chisholm studies an extremely tiny microorganism that plays an enormous role in ocean ecosystems. Discovered only three decades ago, it has defined her career and inspired her to think differently about life on Earth. Full bio
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to a tiny microorganism
that made it possible for us to evolve,
our dependency on fossil fuel.
three billion billion billion
until 35 years ago.
might have looked something like this.
into the one we enjoy today,
of Prochlorococcus evolved
of oxygen and hydrogen.
out of the atmosphere
and proteins and amino acids,
that larger organisms could evolve.
in their carbon bonds.
in the form of coal and oil.
from those ancient microbes,
all of life on earth.
using the solar energy
out of sunlight and carbon dioxide.
with the plants on land:
the pastures, the crops.
with billions of tons of animals.
200 meters of the ocean,
open ocean ecosystem.
live among them and eat them,
to feed on them at night,
and wait for them to die and settle down
one percent of all the plants on land,
as much as all of the plants on land,
50 billion tons of carbon
into their bodies
and all that to maintain.
and grow and divide.
little photosynthesis machines.
of different species of phytoplankton,
of a human hair.
some of the more beautiful ones,
species of phytoplankton.
of schmutz on a microscope slide.
to you in a minute.
how they were discovered.
in my lab called flow cytometry
for studying cells like cancer cells,
for this off-label purpose
and it was beautifully suited to do that.
in this tiny little capillary tube,
according to their size
to whatever pigments they might have,
or whether you stain them.
when you shine blue light on it.
for several years
ones that I showed you,
well wouldn't it be really cool
like this out on a ship
of phytoplankton would look like.
in flow cytometry,
from the company
they would take it back.
that I was working with at the time,
to take this thing apart,
and take it off to sea.
because we thought the ship's vibrations
of the focusing of the laser,
distributions across the ocean.
one cell at a time in real time
that was very exciting.
some faint signals
really behaving like noise.
the width of a human hair
on that same sample,
photosynthetic cell on the planet.
to give them the name Prochlorococcus,
by these little cells
to study them and nothing else,
has really paid off.
including bringing me here.
we and others, many others,
across the oceans
over wide, wide ranges
in what are called the open ocean gyres.
as the deserts of the oceans,
Prochlorococcus cells per liter.
like we do in our cultures,
has a billion Prochlorococcus in it,
of them on the planet.
more than the human population
as much as all of the crops on land.
in the global ocean.
as we were studying them
across so many different habitats?
are different ecotypes.
to the high-light intensities
to the low light in the deep ocean.
in the bottom of the sunlit zone
photosynthesizers of any known cell.
that there are some strains
at the cooler temperatures
and kept finding more and more diversity,
how diverse are these things?
possible to sequence their genomes
and look at their genetic makeup.
the genomes of cultures that we have,
individual cells from the wild
hundreds of Prochlorococcus.
has roughly 2,000 genes --
of the human genome --
a thousand of those in common
for each individual strain
that the cell might have thrived in,
or high or low temperature,
nutrients that limit them
that they come from.
it comes with these built-in apps.
if you're an iPhone person.
and they don't have x's.
you can't get rid of them.
of apps to draw upon
for your particular lifestyle and habitat.
you'll have a lot of travel apps,
you might have a lot of financial apps,
what you want to hear.
couple days in Vancouver
you just need an umbrella.
something about how you live your life,
of a Prochlorococcus cell
in its environment.
through its day or its week,
sequenced hundreds of these cells,
federation, as we call it.
of the human genome.
regions of the oceans
than is healthy --
a masterpiece they are,
of years of evolution.
all of our human ingenuity
in the form of organic carbon,
in those carbon bonds.
exactly how they do this,
our dependency on fossil fuels,
that we're burning
for the earth to bury those,
in the blink of an eye
in the atmosphere.
what is that going to do
that my beloved microbes are doomed,
will expand as the ocean warms
for Prochlorococcus of course --
that we've undertaken,
to be reduced in numbers,
the zooplankton that feed the fish
my muse for the past 35 years,
of other microbes out there
so they can tell their stories, too.
ABOUT THE SPEAKERPenny Chisholm - Microbial oceanographer, author
Penny Chisholm studies an extremely tiny microorganism that plays an enormous role in ocean ecosystems. Discovered only three decades ago, it has defined her career and inspired her to think differently about life on Earth.
Why you should listen
Penny Chisholm (whose scientific works are published under the name Sallie Chisholm) has been studying microscopic plants called phytoplankton since she was an undergraduate. After she joined the MIT faculty, in the 1980s she was lucky enough to be involved in the discovery of the smallest and most abundant phytoplankter on the planet: Prochlorococcus. Less that 1/100th the width of a human hair, this tiny photosynthetic microbe thrives in the sunlit surface waters across large swaths of the global ocean, where it uses the sun's energy to release oxygen, consume carbon dioxide and grow. There are an estimated three billion billion billion of these tiny cells in the global ocean where they provide sustenance for other microorganisms and fuel ocean food webs. "Prochlorococcus has been my muse for more than 30 years," Chisholm says. "It has taught me an enormous amount about the role of photosynthesis in shaping our planet, and about the power of diversity. Most important, it has taught me to be humbled by the mind-blowing complexity of the natural world."
Chisholm is one of ten Institute Professors at MIT and has received many honors for her research on Prochlorococcus, including the 2011 National Medal of Science awarded by President Obama at the White House. She has also co-authored a series of children's books about the role of photosynthesis in shaping our world.
Penny Chisholm | Speaker | TED.com