Ninety miles from the sea, bone white against the muddy black banks of the Alabama River, the sand dollar stands out. The distinctive, petal-like pattern on its surface is perfect and unmistakable, ...
New work on echinoids -- marine animals like sea urchins and sand dollars -- gives scientists a reason to rethink a classical pattern of evolution. Fossil-based studies have traditionally indicated ...
Sand dollar skeletons and fossils turn Ocean Beach into a living lab—perfect for a family day trip. Sand dollar skeletons, or “tests,” wash up in great numbers on San Francisco’s Ocean Beach.