Visit the ammonite and cephalopod collections at the American Museum of Natural History anytime during normal operating hours.
Happy Cephalopod Week! When you think of an ammonite, you probably think of a spiral-shelled sea creature. But in fact, this was just one of the many shapes that ammonites took. Museum Curator Neil Landman explains how this array of shapes once confounded evolutionary biologists, and why this variety is actually a good example of how evolution works.