Ключевые слова: ancient, animal, arthropod, artifact, beetle, biology, brown, cambrian, detail, devonian, dinosaur, evolution, exoskeleton, extinct, extinction, fossil, fossilization, fossilized, geological, geology, imprint, invertebrate, jurassic, limestone, marine, mineral, museum, natural, nature, ocean, old, ordovician, palaeontology, paleontology, paleozoic, prehistoric, prehistory, rock, science, sea, sea animals, shell, skeleton, spiral, stone, trilobite,