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Thank You Very Much for Sharing Us This Beautiful Movie. Aside from The Thank you very much for sharing us this beautiful movie. Aside from the aesthetic side, the movie is also full to the brim with science, so I think that this is a really extraordinary movie. Briefly, it can be summarized that movie tells a story of cave arts found in Sulawesi, Indonesia. Along the movie, we have heard scientists, such as Maxime Aubert from Griffith University Queensland, Australia, Chris Stringer from Natural History Museum UK and Muhammad Ramli, from the preservation of Cultural Reserves Association, Indonesia, explain about the finding, the age estimation, the condition of the artworks and its implication to the theory of early human creativity and human migration. So, as we see at the end of the movie, this finding has been published in Nature, journal with the highest impact factor if I’m not mistaken, stressing the importance of the finding. The article is titled “Pleistocene cave art from Sulawesi, Indonesia’ and it was published last year. In this title we have the word Pleistocene. As I imagine that many of us here are not familiar with this term, as did I, please let me explain a bit about it. The geological eras can be drawn like this. First we have Hadea, Archean, and pterozoic, which collectively called Pre-Cambrian. The time after that, marked by the emergence of animal and plant life, is called phanerozoic, means visible life. Phanerozoic is divided into three eras, Paleozoic, Mesozoic and Canozoic. We will focus on the latter stage of Cenozoic or called age of mammals, due to the mammal emergence in this era. Paleogene, Neogene and Quaternary are included in this era. Quaternary is the last stage, we have modern animals here, and divided into 2, Pleistocene and Holocene. Finally, we found Pleistocene. Pleistocene era ranged from 3 million years ago until now and was a really important era, because the ice age happened here. The ice age was triggered since the Paleogene era, but the worst effect was in Pleistocene era. The dramatic climate change was caused by greenhouse gas, specifically carbon dioxide concentration in the atmosphere. In the beginning of the era, the concentration of carbon dioxide was high and the temperature was warm, really warm. But afterwards, there was a bloom of freshwater fern and subsequent dying-out, which caused the draw-down of CO2 in amount high enough to cause climate change. This event is so famous it got special term, Azolla event. The climate change at the time was so severe, causing the icehouse temperature, terrible drought in Africa, and forced evolution of animals and human if they did want to be extinct. Back to the movie content, I think the main issue in here is the dawn of human creativity. What distinguishes the cave arts found in Sulawesi from other ancient works is the estimated age of the arts. From several artworks found there, the oldest are estimated to be drawn almost 40 thousand years ago. These are the most prominent findings, a hand stencil and a picture of female babirusa. The hand stencil was made by pressing the hand into the wall and spraying wet pigment around it, while the babirusa was drawn using some kind of tools, finger or perhaps stick, dipped into the pigment. It may not be so clear in the original color and shape, but after image enhancements, we can see clearly the artworks. To measure the age of the paintings, they took several layers around the paintings, from behind the pigment layer and several layers after the pigment. From behind the painting, they took flowstone deposit on the rock face and after the painting, the presence of cave popcorn help to provide calcium carbonate that contain radioactive uranium for dating. The result is written in here. The minimum age of these painting are around 40.000 years ago in the Pleistocene era, as the cave popcorn was deposited after the paintings were made. This means that the paintings are at least the same age as the cave popcorn, or even older. So, these paintings are the same age as or even older than artworks found in Europe. Before this finding, the oldest artworks ever found with the age of 40 thousand years ago were found only in Europe, like German and France. Artworks found in other parts of the world are considerably younger. So, as said by Stringer in the movie, up until now it was thought that creativity starts in Europe and that art develop later and independently in other place. Now, with this finding, that theory becomes obsolete, as clearly, our ancestors in both places created artworks at roughly the same time. And also, I think that this issue of early human creativity is closely intertwined with the human migration route. I have here the estimated human journey from national geographic, based on fossil records and DNA evidence derived from fossils. According to research, human journey can be divided into 6 steps: African cradle, out of Africa, the first Australians, early Europeans, populating Asia and into the new world of America. 1. Now, for the first step, African cradle, most paleoanthropologist and geneticists agree that modern humans arose some 200,000 years ago in Africa, based on the age of bones (oldest bones are found in Africa) and vast genetic diversity in Africa. Vast genetic diversity can only happen after mutations over millennia. 2. Afterwards, genetic data showed that a small group of this population left Africa some 70.000 to 50.000 years ago, so this is step 2, out of Africa. 3. This small group is estimated to travel along the coastal route of Southern Asia and reached Australia almost 50.000 year ago. The Aborigines in Australia is probably the descendants of this early human. 4. At point 4, scientists long thought that Europe was habituated first by a direct migration from Africa, but genetic data showed that around 40.000 years before now, humans pushed into Central Asia and arrives on the north of Himalaya. At the same time, they traveled through Southeast Asia and China, reaching Japan and Siberia. That means, Asia was peopled before Europe. 5. As for Europe, it is hypothesized that an inland migration from Asia seeded Europe between 40.000 and 30.000 years ago. 6. Lastly, America. Exactly when the first people arrived in America is still debated. Genetic evidence suggests the period between 20.000 and 15.000 years ago, when the sea levels were low and land connected Siberia to Alaska. Back to the finding, the presence of cave art in Asia with the same age or even older than earliest artworks found in Europe indicated that the theory that stated that human creativity first emerge in Europe was wrong. It also cannot be said that art develop independently in different parts of the world. In the last part of the movie, Stringer stated that the human possessing creativity take their artistic streak when they migrate out of Africa to Asia, Southeast Asia and Australia. This means that the artistic trait has been possessed from the very early ancestors in Africa and after the migration, the trait was manifested in the creation of artworks in the new place at roughly the same time. It is interesting to note, that even though modern human evolved around 200,000 years ago, the oldest artworks found were around 40.000 years old, which means that human started to create artworks after the migration and not before, or maybe it is just when they started to use long lasting media of stone, even though how they could use stone at the same time at so different places is beyond me. .
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