These animal migrations are huge — and invisible
Carl Zimmer writes: Last week, ladybugs briefly took over the news cycle. Meteorologists at the National Weather Service were looking over radar images in California on the night of June 4 when they spotted what looked like a wide swath of rain. But there were no clouds. The meteorologists contacted an amateur weather-spotter directly under the mysterious disturbance. He wasn’t getting soaked by rain. Instead, he saw ladybugs. Everywhere. Radar apparently had picked up a cloud of migrating ladybugs spread…