The deep ocean seems so remote that it is difficult to imagine any sort of human-generated change making an impact on deep-sea life. It is even more difficult to collect or examine evidence from the deep ocean to determine what those impacts might be. Enter the barnacle; a hard, sessile creature that looks like a tiny volcano and attaches to rocks, boat bottoms, and other hard substrates, where it filters ocean water to feed on tiny organisms. The barnacle holds clues about how climate change is affecting the deep ocean. ...