0:00:07.633,0:00:10.073 There's something about caves. 0:00:11.253,0:00:13.057 A shadowy opening in a limestone[br]cliff that draws you in. 9:59:59.000,9:59:59.000 As you pass through the portal[br]between light and dark, 9:59:59.000,9:59:59.000 you enter a subterranean world. 9:59:59.000,9:59:59.000 A place of perpetual gloom, 9:59:59.000,9:59:59.000 a place of earthy smells,[br]of hushed silence. 9:59:59.000,9:59:59.000 Long ago in Europe, 9:59:59.000,9:59:59.000 ancient people also entered[br]these underground worlds. 9:59:59.000,9:59:59.000 As witness to their passage, 9:59:59.000,9:59:59.000 they left behind mysterious[br]engravings and paintings. 9:59:59.000,9:59:59.000 Like this panel of humans, triangles[br]and zig-zags from Ojo Guareña in Spain. 9:59:59.000,9:59:59.000 You now walk the same path[br]as these early artists. 9:59:59.000,9:59:59.000 And in this surreal, other-worldly place, 9:59:59.000,9:59:59.000 it's almost possible to imagine 9:59:59.000,9:59:59.000 that you hear the muffled foot-fall[br]of skin boots on soft earth, 9:59:59.000,9:59:59.000 or you see flickering of a torch[br]around the next bend. 9:59:59.000,9:59:59.000 When I'm in a cave, 9:59:59.000,9:59:59.000 I often find myself wondering,[br]what drove these people to go so deep? 9:59:59.000,9:59:59.000 to brave dangerous and narrow[br]passageways to leave their mark? 9:59:59.000,9:59:59.000 In this video clip, 9:59:59.000,9:59:59.000 that was shot half a kilometer,[br]or about a third of a mile underground, 9:59:59.000,9:59:59.000 in the cave of Curon in Spain, 9:59:59.000,9:59:59.000 we found a series[br]of red paintings on a ceiling 9:59:59.000,9:59:59.000 in a previously unexplored[br]section of the cave. 9:59:59.000,9:59:59.000 As we crawled forward, military-style,[br]with the ceiling getting ever-lower, 9:59:59.000,9:59:59.000 we finally got to a point[br]where the ceiling was so low, 9:59:59.000,9:59:59.000 that my husband and project[br]photographer, Dylan, 9:59:59.000,9:59:59.000 could no longer achieve focus[br]on the ceiling with his DSLR camera. 9:59:59.000,9:59:59.000 So while he filmed me, 9:59:59.000,9:59:59.000 I kept following the trail of red paint[br]with a single light, 9:59:59.000,9:59:59.000 and a point-and-shoot camera[br]that we kept for that type of occasion. 9:59:59.000,9:59:59.000 Half a kilometer underground. 9:59:59.000,9:59:59.000 Seriously. 9:59:59.000,9:59:59.000 What was somebody doing down there[br]with a torturous stone lamp? 9:59:59.000,9:59:59.000 (Laugher) 9:59:59.000,9:59:59.000 I mean --me, it makes sense, right? 9:59:59.000,9:59:59.000 But you know, 9:59:59.000,9:59:59.000 this is the kind of question that[br]I'm trying to answer with my research. 9:59:59.000,9:59:59.000 I study some of[br]the oldest art in the world. 9:59:59.000,9:59:59.000 It was created by these[br]early artists in Europe, 9:59:59.000,9:59:59.000 between 10 thousand[br]and 40 thousand years ago. 9:59:59.000,9:59:59.000 And the thing is, 9:59:59.000,9:59:59.000 is that I'm not just studying it[br]because it's beautiful, 9:59:59.000,9:59:59.000 though some of it certainly is. 9:59:59.000,9:59:59.000 But what I'm interested in[br]is the development of the modern mind, 9:59:59.000,9:59:59.000 of the evolution of creativity,[br]of imagination, of abstract thought. 9:59:59.000,9:59:59.000 About what it means to be human. 9:59:59.000,9:59:59.000 While all species communicate[br]in one way or another, 9:59:59.000,9:59:59.000 only we humans have really taken it[br]to another level. 9:59:59.000,9:59:59.000 Our desire and ability[br]to share and collaborate, 9:59:59.000,9:59:59.000 has been a huge part of out success story. 9:59:59.000,9:59:59.000 Our modern world is based on a global[br]network of information exchange. 9:59:59.000,9:59:59.000 Made possible, in large part,[br]by our ability to communicate. 9:59:59.000,9:59:59.000 In particular, using graphic[br]or written forms of communication. 9:59:59.000,9:59:59.000 The thing is though, 9:59:59.000,9:59:59.000 that we've been building[br]on the mental achievements 9:59:59.000,9:59:59.000 of those that came before us for so long, 9:59:59.000,9:59:59.000 that it's easy to forget that certain[br]abilities haven't already existed. 9:59:59.000,9:59:59.000 It's one of the things[br]I find most fascinating 9:59:59.000,9:59:59.000 about studying our deep history. 9:59:59.000,9:59:59.000 Those people didn't have the shoulders[br]of any giants to stand on, 9:59:59.000,9:59:59.000 they were the original shoulders. 9:59:59.000,9:59:59.000 And while a surprising number[br]of important inventions 9:59:59.000,9:59:59.000 come out of that distant time, 9:59:59.000,9:59:59.000 what I want to talk to you about today[br]is the invention of graphic communication. 9:59:59.000,9:59:59.000 There are three[br]main types of communication, 9:59:59.000,9:59:59.000 spoken, gestural -- [br]so things like sign language, 9:59:59.000,9:59:59.000 and graphic communication. 9:59:59.000,9:59:59.000 Spoken and gestural are,[br]by their very nature, ephemeral. 9:59:59.000,9:59:59.000 It requires close contact for a message[br]to be sent and received. 9:59:59.000,9:59:59.000 And after the moment of transmission,[br]it's gone forever. 9:59:59.000,9:59:59.000 Graphic communication, on the other hand,[br]decouples that relationship, 9:59:59.000,9:59:59.000 and with its invention, it became possible[br]for the first time, 9:59:59.000,9:59:59.000 for a message to be[br]transmitted and preserved, 9:59:59.000,9:59:59.000 beyond a single moment in place and time. 9:59:59.000,9:59:59.000 Europe is one of the first places 9:59:59.000,9:59:59.000 that we start to see graphic marks[br]regularly appearing 9:59:59.000,9:59:59.000 in caves, rock shelters, and even[br]a few surviving open air sites. 9:59:59.000,9:59:59.000 But this is not the Europe we know today. 9:59:59.000,9:59:59.000 This was a world dominated[br]by towering ice sheets 9:59:59.000,9:59:59.000 by towering ice sheets, three to four[br]kilometers high, 9:59:59.000,9:59:59.000 with sweeping grass plains[br]and frozen tundra. 9:59:59.000,9:59:59.000 This was the Ice Age. 9:59:59.000,9:59:59.000 Over the last century, 9:59:59.000,9:59:59.000 more than 350 Ice Age rock art sites[br]have been found across the continent. 9:59:59.000,9:59:59.000 Decorated with animals, abstract shapes,[br]and even the occasional human. 9:59:59.000,9:59:59.000 Like these engraved figures[br]from Grotta dell'Addaura in Sicily. 9:59:59.000,9:59:59.000 They provide us with a rare glimpse[br]into the creative world 9:59:59.000,9:59:59.000 into the creative world and imagination[br]of these early artists. 9:59:59.000,9:59:59.000 Since their discovery, 9:59:59.000,9:59:59.000 it's been the animals that have received[br]the majority of the study. 9:59:59.000,9:59:59.000 Like this black horse from [br], Spain. 9:59:59.000,9:59:59.000 Or this unusual purple bison[br]from La Pasiega. 9:59:59.000,9:59:59.000 But for me, it was the abstract shapes,[br]what we call geometric signs, 9:59:59.000,9:59:59.000 that drew me to study the art. 9:59:59.000,9:59:59.000 The funny this is, that at most sights, 9:59:59.000,9:59:59.000 the geometric signs far outnumber[br]the animal and human images. 9:59:59.000,9:59:59.000 But when I started on this back in 2007, 9:59:59.000,9:59:59.000 there wasn't even a definitive list[br]of how many shapes there were, 9:59:59.000,9:59:59.000 nor was there a strong sense 9:59:59.000,9:59:59.000 of whether the same ones appeared[br]across space or time. 9:59:59.000,9:59:59.000 Before I could even[br]get started on my questions, 9:59:59.000,9:59:59.000 my first step was to compile a database 9:59:59.000,9:59:59.000 of all known geographic signs[br]from all of the rock art sites. 9:59:59.000,9:59:59.000 The problem was that while they were[br]well documented at some sights, 9:59:59.000,9:59:59.000 usually the ones[br]with the very nice animals, 9:59:59.000,9:59:59.000 there was also a large number of them[br]where it was very vague -- 9:59:59.000,9:59:59.000 there wasn't a lot[br]of description or detail. 9:59:59.000,9:59:59.000 Some of them hadn't been visited[br]in half a century, or more. 9:59:59.000,9:59:59.000 These were the ones[br]that I targeted for my field work. 9:59:59.000,9:59:59.000 Over the course of two years,[br] 9:59:59.000,9:59:59.000 my faithful husband Dylan and I[br]each spent over 300 hours underground, 9:59:59.000,9:59:59.000 hiking, crawling and wriggling[br]around 52 sites 9:59:59.000,9:59:59.000 in France, Spain, Portugal and Sicily. 9:59:59.000,9:59:59.000 And it was totally worth it. 9:59:59.000,9:59:59.000 We found new, undocumented geometric signs[br]at 75 percent of the sites we visited. 9:59:59.000,9:59:59.000 This is the level of accuracy[br]I knew I was going to need 9:59:59.000,9:59:59.000 if I wanted to start answering[br]those larger questions. 9:59:59.000,9:59:59.000 So let's get to those answers. 9:59:59.000,9:59:59.000 Barring a handful of outliers,[br]there are only 32 geometric signs. 9:59:59.000,9:59:59.000 Only 32 signs across[br]a 30 thousand year time span, 9:59:59.000,9:59:59.000 and the entire continent of Europe. 9:59:59.000,9:59:59.000 That is a very small number. 9:59:59.000,9:59:59.000 Now if these were random[br]doodles or decorations, 9:59:59.000,9:59:59.000 we would expect to see[br]a lot more variation, 9:59:59.000,9:59:59.000 but instead what we find[br]are the same signs, 9:59:59.000,9:59:59.000 repeating across both space and time. 9:59:59.000,9:59:59.000 Some signs start out strong,[br]before losing popularity and vanishing, 9:59:59.000,9:59:59.000 while other signs are later inventions. 9:59:59.000,9:59:59.000 But 65 percent of those signs stayed[br]in use during that entire time period. 9:59:59.000,9:59:59.000 Thigns like lines, rectangles, trianagles,[br]ovals and circles. 9:59:59.000,9:59:59.000 Like we see here[br]from the end of the Ice Age 9:59:59.000,9:59:59.000 at a 10 thousand-year-old site,[br]high in Pyrenees Mountains. 9:59:59.000,9:59:59.000 And while certain signs span[br]thousands of kilometers, 9:59:59.000,9:59:59.000 other signs had restricted[br]distribution patterns, 9:59:59.000,9:59:59.000 with some being limited[br]to a single territory, 9:59:59.000,9:59:59.000 like we see here with these[br]divided rectangles 9:59:59.000,9:59:59.000 that are only found in northern Spain, 9:59:59.000,9:59:59.000 and what some researchers have speculated 9:59:59.000,9:59:59.000 could be some sort[br]of family or clan signs. 9:59:59.000,9:59:59.000 On a side note, 9:59:59.000,9:59:59.000 there is surprising degree similarity[br]in the earliest rock art 9:59:59.000,9:59:59.000 found all the way from France and Spain[br]to Indonesia and Australia. 9:59:59.000,9:59:59.000 With many of the same signs[br]appearing in such far-flung places, 9:59:59.000,9:59:59.000 especially in the 30 thousand[br]to 40 thousand-year range, 9:59:59.000,9:59:59.000 it's starting to seem increasingly likely 9:59:59.000,9:59:59.000 that this convention actually traces back[br]to a common point of origin in Africa, 9:59:59.000,9:59:59.000 but that I'm afraid, is a subject[br]for a future talk. 9:59:59.000,9:59:59.000 So back to the matter at hand. 9:59:59.000,9:59:59.000 There could be no doubt that these signs[br]were meaningful to their creators, 9:59:59.000,9:59:59.000 like these 25 thousand-year-old[br]___________ sculptures 9:59:59.000,9:59:59.000 from La Roque de Venasque in France. 9:59:59.000,9:59:59.000 We might not know what they meant[br]but the people of the time certainly did. 9:59:59.000,9:59:59.000 The repetition of the same signs,[br]for so long, and at so many sites, 9:59:59.000,9:59:59.000 tells us that the artists[br]were making intentional choices, 9:59:59.000,9:59:59.000 If we're talking about geometric shapes, 9:59:59.000,9:59:59.000 with specific, culturally recognized,[br]agreed upon meanings, 9:59:59.000,9:59:59.000 than we could very well be looking 9:59:59.000,9:59:59.000 at one of the oldest systems of graphic[br]communication in the world. 9:59:59.000,9:59:59.000 I'm not talking about writing yet. 9:59:59.000,9:59:59.000 There's just not enough[br]characters at this point, 9:59:59.000,9:59:59.000 to have represented all of the words[br]in the spoken language, 9:59:59.000,9:59:59.000 something which is a requirement[br]for a full writing system. 9:59:59.000,9:59:59.000 Nor do we see the signs[br]repeating regularly enough 9:59:59.000,9:59:59.000 to suggest that they were[br]some sort of alphabet. 9:59:59.000,9:59:59.000 But what we do have[br]are some intriguing one-offs 9:59:59.000,9:59:59.000 like this panel from La Pasiega in Spain[br]known as "The Inscription", 9:59:59.000,9:59:59.000 with its symmetrical markings on the left, 9:59:59.000,9:59:59.000 possible stylized representations[br]of hands in the middle, 9:59:59.000,9:59:59.000 and what looks a bit like[br]a bracket on the right. 9:59:59.000,9:59:59.000 The oldest systems of graphic[br]communication in the world -- 9:59:59.000,9:59:59.000 Sumerian cuneiform, Egyptian hieroglyphs,[br]the earliest Chinese script, 9:59:59.000,9:59:59.000 all emerged between four thousand[br]and five thousand years ago, 9:59:59.000,9:59:59.000 with each coming into existence[br]from an earlier protosystem 9:59:59.000,9:59:59.000 made of counting marks[br]and pictographic representations, 9:59:59.000,9:59:59.000 where the meaning[br]and the image were the same. 9:59:59.000,9:59:59.000 So a picture of a bird would really have[br]represented that animal. 9:59:59.000,9:59:59.000 It's only later that we start to see[br]these pictographs become more stylized, 9:59:59.000,9:59:59.000 until they almost become unrecognizable. 9:59:59.000,9:59:59.000 And that we also start to see 9:59:59.000,9:59:59.000 more symbols being invented to represent[br]all those missing words in the language -- 9:59:59.000,9:59:59.000 things like pronouns, adverbs, adjectives. 9:59:59.000,9:59:59.000 So knowing all this, 9:59:59.000,9:59:59.000 it seems highly unlikely the geometrics[br]signs from Ice Age Europe 9:59:59.000,9:59:59.000 were truly abstract written characters. 9:59:59.000,9:59:59.000 Instead what's much more likely 9:59:59.000,9:59:59.000 is that these early artists[br]were also making counting marks, 9:59:59.000,9:59:59.000 maybe like this row lines[br]from Reparo de Za Minica in Sicily, 9:59:59.000,9:59:59.000 as well as creating stylized[br]representations 9:59:59.000,9:59:59.000 of things from the world around them. 9:59:59.000,9:59:59.000 Could some of the signs[br]be weaponry or housing? 9:59:59.000,9:59:59.000 Or what about celestial objects[br]like star constellations? 9:59:59.000,9:59:59.000 Or maybe even rivers, mountains,[br]trees-- landscape features. 9:59:59.000,9:59:59.000 Possibly like this black peniform[br]surrounded by strange bell-shaped signs 9:59:59.000,9:59:59.000 from the site of El Castillo, in Spain. 9:59:59.000,9:59:59.000 The term peniform means[br]"feather-shaped" in Latin, 9:59:59.000,9:59:59.000 but could this actually be[br]a depiction of a plant or a tree? 9:59:59.000,9:59:59.000 Some researchers have begun 9:59:59.000,9:59:59.000 to ask these questions[br]about certain signs at specific sites, 9:59:59.000,9:59:59.000 but I believe the time has come[br]to revisit this category as a whole. 9:59:59.000,9:59:59.000 The irony in all of this, of course, 9:59:59.000,9:59:59.000 is that having just carefully classified[br]all the signs into a single category, 9:59:59.000,9:59:59.000 I have a feeling that my next step[br]will involve breaking it back apart 9:59:59.000,9:59:59.000 as different types of imagery[br]are identified and separated off. 9:59:59.000,9:59:59.000 Now don't get me wrong, 9:59:59.000,9:59:59.000 the later creation[br]of fully-developed writing 9:59:59.000,9:59:59.000 was an impressive feat in its own right, 9:59:59.000,9:59:59.000 but it's important to remember 9:59:59.000,9:59:59.000 that those early writing systems[br]didn't come out of a vacuum. 9:59:59.000,9:59:59.000 And that even five thousand years ago, 9:59:59.000,9:59:59.000 people were already building[br]on something much older, 9:59:59.000,9:59:59.000 with its origins stretching back[br]tens of thousands of years -- 9:59:59.000,9:59:59.000 to the geometric signs[br]of Ice Age Europe and far beyond, 9:59:59.000,9:59:59.000 to that point, deep in our[br]collective history, 9:59:59.000,9:59:59.000 when someone first came up with the idea[br]of making a graphic mark, 9:59:59.000,9:59:59.000 and forever changed the nature[br]of how we communicate. 9:59:59.000,9:59:59.000 Thank you. 9:59:59.000,9:59:59.000 (Applause)