A graduate student has created the first man-made biological leaf. It absorbs water and carbon dioxide to produce oxygen just like a plant. He did this by suspending chloroplasts in a mixture made out of silk protein. He believed it can be used for many things but the most striking one is the thought that it could be used for long distance space travel. Plants do not grow in space, but this synthetic material can be used to produce oxygen in a hostile environment. (Video)
The Incan stonework is famous for it’s large stones (some over 100 tons) that fit so precisely together that “not even a knife could be inserted between the joints.”
How the Incans were able to transport these massive building blocks and handled is something we don’t quite understand today. What we do know is that the cutting marks on some of the stone blocks are very similar to those found on the pyramidion of the unfinished obelisk in Egypt.