Tiny Twilight Zone

Not far beneath the ocean’s surface, tiny phytoplankton swimming upward in a daily commute toward morning light sometimes encounter the watery equivalent of Rod Serling’s Twilight Zone: a sharp variation in marine currents that traps billions of these single-celled organisms and sends them tumbling until a shift in wind or tide alters the currents and sets them free. Scientists are aware of these thin layers of single-celled creatures and their enormous ecological ramifications, but until now, they knew little about the mechanisms responsible for their formation. The movie is displayed at 7.2 times the actual speed. Courtesy / William M. Durham. credit: MIT