University of Sheffield; Emily Elert (zoomable version)
Scientists recently mapped the evolutionary history of all bird species, paying particular attention to speciation events as a function of time. The graphic shows, via color, that much of the bird speciation has increased in the last 50 million years. In fact, speciation in new-world birds has happened at the greatest clip, within the last 20 million years (yellow and red sections on the graph).
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.