An unusual type of fossil clam is found in rock layers high in the Swiss Alps. The same type of fossil clam is also found in the Rocky Mountains of North America. From this, scientists Conclude that glaciers carried the fosils up the mountains. Othe Rocky Mountains and the Swiss Aips are both volcanic in origin clams once lived in mountains, but have since evolved into sea-dwelling creature. O1 the layers of rocks in which the fossis were found are from the same geologic age