A Swell Shell

Ancestors of the nautilus were “the great white sharks” of the prehistoric seas. They evolved an edge that made them efficient hunters: a shell that allowed them to float—and stalk other ancient creatures still stuck crawling around on the ocean floor. Today’s nautiluses are smaller and more mild mannered than their ancestors from 500 million […]

Aliens of the Sea?

Wading in the icy waters of Maine’s Penobscot Bay one summer day, I spotted transparent creatures near the surface rippling with rainbow bands of light. I thought I was seeing things until a scientist friend told me that these thumb-long, otherworldly critters are called comb jellies. He explained that their namesake “combs” — rows of […]