Fossils explained 79

Rugose corals are an extinct group of marine animals that are frequently found in Palaeozoic shallow marine sediments. Just like their counterparts the stony corals (the Scleractinia) do today, during the Palaeozoic the rugose corals were important constructors of reefs. Although at first glance rugose corals look very similar to the Scleractinia, they differ in important details. The rugose corals are a very special group whose relationships have been disputed for a long time. They were restricted to the Palaeozoic Era and experienced an exciting evolutionary history of victories and defeats; there were times when they built up huge reefs (and were valuable in stratigraphy), and other times when they suffered through extinction events.     

Fossils explained 78

The coastal town of Margate in north Kent, south-east England, is geologically well known, with extensive cliffs of chalk with locally common Upper Cretaceous fossils. But to the ichnologist the modern beach is at least as fascinating, with a trinity of borings in chalk clasts and mollusc shells posing interesting questions relevant to palaeoecology and taphonomy.