"Keepers were feeding the beavers and hooded mergansers (a species of duck) when the earthquake hit. The ducks immediately jumped into the pool. The beavers stopped eating, stood on their hind legs and looked around, then got into the water, too. They all stayed in the water. Within an hour, some of the beavers returned to land to continue eating."
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.