♪
NARRATOR: It creeps!
It crawls!
It's this big, blobby yellow thing.
NARRATOR: It's slime mold!
♪
A slithering shape-shifter like no other on this planet.
AUDREY DUSSUTOUR (translated): It reminded us
of this alien organism from a '50s movie
that ate people. (people screaming)
MOVIE ANNOUNCER: "The Blob"!
NARRATOR: This one-celled wonder has no brain.
TANYA LATTY: No brain, no organs, no neurons.
Yet it's able to do some of the behaviors
we normally associate with animals with brains.
NARRATOR: How does it solve a maze?
It is amazing.
NARRATOR: Escape captivity?
Compete for resources?
Build efficient networks?
DUSSUTOUR (translated): You start to think, does this organism
possess intelligence?
MICHAEL LEVIN: All of these are fundamental components
to being smart.
NARRATOR: No brain?
No problem.
LEVIN: Clearly now, we see
that this can be done by one cell.
NARRATOR: Can this ancient organism shed new light
on the evolutionary origins of intelligence?
LATTY: We can think of them as how intelligence started
way back.
NARRATOR: "The Secret Mind of Slime,"
next, on "NOVA."
♪
ANNOUNCER: Major funding for "NOVA" is provided by the following:
♪
NARRATOR: Lurking in the forest's shadowy undergrowth
lies an unlikely predator.
It creeps along, stalking its prey.
Yet it is not an animal.
It has a fondness for dark, humid places,
yet it is not a fungus
nor a plant.
It's a single-celled organism,
but not a bacterium.
♪
It's known as slime mold.
It has no eyes, no mouth, no stomach,
no legs.
Yet it can "see," "smell,"
and move around
through its pulsating network of veins,
gorging itself on bacteria,
fungi,
yeasts,
and growing exponentially.
This strange yet humble creature holds secrets that have
biologists, neuroscientists, and mathematicians
scratching their heads.
Because this organism, without a brain or a nervous system,
seems capable of making choices,
solving complex problems,
and devising strategies.
And it is forcing scientists to rethink intelligence
as something that does not imply a need for a brain.
♪
Tanya Latty is a researcher at the University of Sydney
who studies slime mold.
LATTY: You can find slime mold all over the place.
They're in leaf litter, they're in the soil,
they're on bits of wood.
They're small structures that almost look like mushrooms.
NARRATOR: Not only is Tanya an expert on slime mold,
she's one of its biggest fans.
How could you not love them? (laughs)
It's this big, blobby, yellow thing, you know,
it's just fundamentally cool.
(laughs): I stand by that!
"Slime Mold Identification and Appreciation."
There it is.
NARRATOR: She even follows them on Facebook.
LATTY: The spores are gorgeous.
They're, they're beautiful.
♪
The slime molds might be one of the most abundant things
in the soil.
There are spores everywhere.
♪
NARRATOR: Biologists have puzzled
over where exactly this creature fits
into the great tree of life.
LATTY: Slime molds branched off from that tree
before the plants, the fungi, and the animals.
They're single-celled organisms, but the type of cell they have
is quite different from bacteria.
There's at least 900 different species of slime mold
that we know about,
and that number is probably a massive underestimate.
♪
The slime mold most people think about
is Physarum polycephalum.