These lovely watercolor sketches are of Trapezia crabs. These crabs have a variety of coloring and live on and within corals, feeding on their tissue and mucus, and, in exchange, protect them from predators such as starfish.
These watercolors were done by Frederick Bayer, a Smithsonian biologist who studied a coral reef before and after it was used for nuclear testing! The water heated to 55,000 degrees Celsius after a nuke was dropped on it, obliterating all wildlife. Bayer made these drawings just a year later, showing that life had already started moving back in. And today, almost 70 years later, it’s a flourishing reef.
Photo Credit: Smithsonian Institution