In the classical era, monstrous creatures such as the Cyclops and the Minotaur appear in heroic tales for the protagonist to destroy. Other creatures, such as the unicorn, were claimed in accounts of natural history by various scholars of antiquity. Some legendary creatures have their origin in traditional mythology and were believed to be real creatures, for example dragons, griffins, and unicorns. Others were based on real encounters, originating in garbled accounts of travelers' tales, such as the Vegetable Lamb of Tartary, which supposedly grew tethered to the earth