Twenty years and 7,500 fossils reveal what blurs Earth's marine fossil record

In productive marine environments, a square meter (10.8 square feet) of seafloor can be perforated by hundreds to thousands of isolated and interconnected tunnels through which crawl and writhe a cornucopia of clams, shrimp, sea stars, sand dollars, snails, worms and other animals.

Originally published at Phys.org