A beehive buzzes with thousands of genetically similar female honeybees. Some nurse their queen and her eggs while others fly out in search of pollen and nectar. For decades, scientists knew that bees took on new jobs as they aged, but a team of researchers recently discovered that chemical tags attached to the bees’ DNA play an important role in determining their career paths.
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.