There's something about caves.
A shadowy opening in a limestone cliff that draws you in.
As you pass through the portal between light and dark,
you enter a subterranean world.
A place of perpetual gloom,
a place of earthy smells, of hushed silence.
Long ago in Europe,
ancient people also entered these underground worlds.
As witness to their passage,
they left behind mysterious engravings and paintings.
Like this panel of humans, triangles and zig-zags from Ojo Guareña in Spain.
You now walk the same path as these early artists.
And in this surreal, other-worldly place,
it's almost possible to imagine
that you hear the muffled foot-fall of skin boots on soft earth,
or you see flickering of a torch around the next bend.
When I'm in a cave,
I often find myself wondering, what drove these people to go so deep?
to brave dangerous and narrow passageways to leave their mark?
In this video clip,
that was shot half a kilometer, or about a third of a mile underground,
in the cave of Curon in Spain,
we found a series of red paintings on a ceiling
in a previously unexplored section of the cave.
As we crawled forward, military-style, with the ceiling getting ever-lower,
we finally got to a point where the ceiling was so low,
that my husband and project photographer, Dylan,
could no longer achieve focus on the ceiling with his DSLR camera.
So while he filmed me,
I kept following the trail of red paint with a single light,
and a point-and-shoot camera that we kept for that type of occasion.
Half a kilometer underground.
Seriously.
What was somebody doing down there with a torturous stone lamp?
(Laugher)
I mean --me, it makes sense, right?
But you know,
this is the kind of question that I'm trying to answer with my research.
I study some of the oldest art in the world.
It was created by these early artists in Europe,
between 10 thousand and 40 thousand years ago.
And the thing is,
is that I'm not just studying it because it's beautiful,
though some of it certainly is.
But what I'm interested in is the development of the modern mind,
of the evolution of creativity, of imagination, of abstract thought.
About what it means to be human.
While all species communicate in one way or another,
only we humans have really taken it to another level.
Our desire and ability to share and collaborate,
has been a huge part of out success story.
Our modern world is based on a global network of information exchange.
Made possible, in large part, by our ability to communicate.
In particular, using graphic or written forms of communication.
The thing is though,
that we've been building on the mental achievements
of those that came before us for so long,
that it's easy to forget that certain abilities haven't already existed.
It's one of the things I find most fascinating
about studying our deep history.
Those people didn't have the shoulders of any giants to stand on,
they were the original shoulders.
And while a surprising number of important inventions
come out of that distant time,
what I want to talk to you about today is the invention of graphic communication.
There are three main types of communication,
spoken, gestural -- so things like sign language,
and graphic communication.
Spoken and gestural are, by their very nature, ephemeral.
It requires close contact for a message to be sent and received.
And after the moment of transmission, it's gone forever.
Graphic communication, on the other hand, decouples that relationship,
and with its invention, it became possible for the first time,
for a message to be transmitted and preserved,
beyond a single moment in place and time.
Europe is one of the first places
that we start to see graphic marks regularly appearing
in caves, rock shelters, and even a few surviving open air sites.
But this is not the Europe we know today.
This was a world dominated by towering ice sheets
by towering ice sheets, three to four kilometers high,
with sweeping grass plains and frozen tundra.
This was the Ice Age.
Over the last century,
more than 350 Ice Age rock art sites have been found across the continent.
Decorated with animals, abstract shapes, and even the occasion human.
Like these engraved figures from Grotta dell'Addaura in Sicily.