“Science on the Half Shell” came about when a group of scientists were offered a grant—as long as they mounted an exhibition on their findings. The Field Museum’s small show (without the marketing push behind “Mummies” or “Genghis Khan”) features bivalves, the taxonomic term for oysters, clams and mussels. The strange beings are worth a look: Some swim around by clapping their shells, see light and darkness through a litany of eyes, burrow into wood by eating it or using shells like sandpaper, and come in sizes up to four feet wide (that’s one big clam). Oddly, the exhibit doesn’t focus much on the beautiful shells or the food’s cultural importance. Rather it mostly contains dense information on DNA sequencing done by the aforementioned scientists. But, when I attended, the lack of digestible information and the dearth of marketing didn’t stop kids from swarming the displays and poking at high-tech DNA gizmos, which they seemed to understand better than I did.