compared to 10 years ago, when i came back from america to china to teach at peking university, the situation is worse. the air-conditioning is worse. now, you can gradually see this problem solved. this is also a matter of balance. the chinese government has the pressure of development. we have 13 million people who want to move to the city every year, which is almost the whole australian population. they want to move to the city. at the same time, we have a shortage of water, for example, a shortage of oil, a shortage of all kinds of natural resources. this is a balance. tavis: kongjian yu was born into a family of farmers. he believes that respect for the land is crucial to the future of this country as an economic boom >> basically, it was taken from america, the consumers idea. to allow the money to invest and consume. in chinese culture, the deep culture, we have a culture of saving. saving energy, saving resources, saving money. we have such a culture because we have such a heavy population and we have such meager resources. we have developed this kind of culture. that is what i want t

the cave's surface was scanned by a chinese team from peking university which spent four weeks at xiangtangshantechnical team in chicago then helped turn the scans into these wireframe images. chicago researchers also traveled the world to scan images of every sculpture and fragment they could find and then placed them digitally in bright yellow back into the cave. in doing so, wilson says, scientists and art historians learned even more about the original site. >> another result of this project has been really building the number of objects that we now know come from the place. >> reporter: how do you figure out that a particular piece actually belonged here? >> a couple of different ways. the old fashioned way is connoisseurship, where you compare the style of one head to another head. you know that this head comes the digitizing has also helped because it records so many details so correctly that in this physical matching that we were talking about it allows us to physically prove that a piece had been removed from the site. >> reporter: of course, this also raises another question: why not