Out of sight above us swarms of insects are riding their own mass-transit system

To us, a clear blue sky on a summer day might be synonymous with peace and serenity, but that’s only because we’re firmly planted on the ground and our vision is limited. Overhead, many thousands of feet in the air, billions (and billions and billions) of creatures we usually see humming only a few feet above the ground are in mass transit. Animated by Benjamin Arthur and reported by Radiolab’s Robert Krulwich, Look Up! The Billion-bug Highway You Can’t See examines the surprising, hidden world of airborne insects. You can read more on NPR’s website.