| Top and bottom--Two complete specimens of the extinct spiny shark called scientifically, Acanthodes bridgei; head is at lower left in specimen at top--head at upper right in the fossil at bottom. Both fossils reveal remarkable preservational aspects--the specimen at top, for example, has the rods and cones preserved intact in its eyes--demonstrating that in actual life Acanthodes bridgei could see in full color. Both came from the upper Pennsylvanian Calhoun Shale, Shawnee Group, Virgilian Stage. Top photograph courtesy a technical scientific paper; image at bottom is from a specific web page. |