I remember when we found the first population of living Cerion agassizi in central Eleuthera. Our hypothesis of Cerion's general pattern required that two predictions be affirmed (or else we were in trouble): this population must disappear by hybridization with mottled shells toward bank-interior coasts and with ribby snails toward the bank-edge. We hiked west toward the bank-interior and easily found hybrids right on the verge of the airport road. We then moved east toward the bank-edge along a disused road with vegetation rising to five feet in the center between the tire paths. We should have found our hybrids but we did not. The Cerion agassizi simply stopped about two hundred yards north of our first ribby Cerion. Then we realized that a pond lay just to our east and that ribby forms, with their coastal preferences, might not favor the western side of the pond. We forded the pond and found a classic hybrid zone between Cerion agassizi and ribby Cerions. (Ribby Cerion had just managed to round the south end of the pond, but had not moved sufficiently north along the west side to establish contact with C. agassizi populations.) I wanted to shout for joy. Then I thought, "But who can I tell; who cares?" And I answered myself, "I don't have to tell anyone. We have just seen and understood something that no one has ever seen and understood before. What more does a man need?

— Stephen Jay Gould

---

#prediction #understanding #nature