To create this image, which won the popular vote in the 2008 Nikon Small World contest, 22-year-old Tomás Pais de Azevedo, a graduate student in evolutionary and developmental biology at the University of Lisbon in Portugal, removed an eight-day-old, two-inch-long chicken embryo from its egg and stained it with a dye that binds to cartilage. The process took three days, after which he photographed the embryo through a stereo microscope. The dark-blue areas of the chick indicate where the cartilage will ultimately solidify into bone. By tracking how bones develop, and in what order, it's possible to see how various genes control the overall development of vertebrate organisms.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.