Mighty Mites

Under a microscope, a copepod looks fearsome, but at only one-sixteenth of an inch, it won’t bother anyone. People seldom see these tiny marine crustaceans, but they may be the most abundant—and among the most important—animals in the sea. Copepods live in all oceans and are a vital link in ocean food chains. They also play an important role in Earth’s carbon cycle by consuming organic matter in the water and excreting carbon-rich material that either becomes food for other animals or sinks into the depths, sequestering the carbon away from the surface for long periods of time. (Photo by Ann Tarrant, Woods Hole Oceanographic Institution)