Perhaps one of the most recognisable fossils, slater-like trilobites of all different shapes and sizes can be found across Lowland Scotland. The most famous Scottish site is Girvan, where a local artist recently created an installation devoted to the celebrity fossils along the harbour. In fact, trilobites were so diverse and widespread in the Palaeozoic oceans that they are now heralded as the one of the most successful early life-forms, with over 20,000 species of trilobite known to science today. Although trilobites are now extinct, they populated the world’s oceans for several hundred million years, and proved incredibly versatile in terms of adaptation to different food sources and ocean habitats.
Trilobites were part of the marine arthropods group – creatures with their segmented skeletons on the outside of their bodies, such as crabs and insects. The classic, curled trilobite fossil found across the world is often the fossilised outer shell of the animal itself – trilobites shed their shells periodically throughout their lifetimes, leading to millions of fossilised shells being left behind. The smallest trilobite was only a few millimetres long, whereas the largest known species was over 70 centimetres in length.