The ancient Hellenes were very keen people, interested in all things nature, science and philosophy. They searched for answers to questions about their life, as well as the Theoi, and they theorized structurally about any discoveries they made, be it in health care, science or paleontology. Especially in the latter department, there are a few discoveries that might have shaped a large part of ancient Hellenic mythology and religion in general. Today, we'll be discussing some of those.
Giants:
Nichoria (Νιχώρια) is a site in Messenia, a regional unit in the southwestern part of the Peloponnese, Greece, on a ridgetop near modern Rizomylos, at the northwestern corner of the Messenian Gulf. It was the home of an Acropolis where many--what we now call--fossils were stored. The Nichoria bone was discovered by the ancient Hellenes roughly around 1000 BC. It is the blackened and petrified thigh bone of an extinct mega mammal--likely a woolly rhinoceros, or a mammoth--that roamed southern Hellas around one million years ago. The rusty-black color of the fossil bone indicates that it was most likely collected from the lignite deposits near the ancient town of Megalopolis, some 55 kilometers (35 miles) away from Nichoria. The Megalopolis basin was known in antiquity as the 'battleground of the Giants', where the Titanomachy was believed to have taken place. The dense concentration of large fossil bones found at the basin inspired the belief that entire armies of giants were blasted by Zeus' thunderbolts, and the Nichoria bone--the distal end of a right femur, 15 cm (5-6 inches) wide, about twice the size of a regular human thigh bone--was most likely believed to have belonged to one of these giants. If the myth or the bone came first is unknown.