Ключевые слова: age, ancient, animal, antiquity, archeology, arthropod, biology, cambrian, crustacean, evolution, extinct, fossil, geology, history, insect, isolated, life, lobes, marine, mineral, natural, nature, ocean, old, ordovician, paleontology, paleozoic, past, prehistoric, research, rock, science, sea, shale, stone, trilobite, wildlife,