In Maori mythology, Ruaumoko (also known as Ruamoko) is the youngest son of Rangi and Papa, god of volcanoes and seasons. He has never been born and remains inside his mother’s womb. His movements are considered the cause of earthquakes. These earthquakes in turn are responsible for the change of seasons. Depending on the time of year, the earthquakes cause the warmth, or cold, of Mother Earth to come to the surface of the land, resulting in the warming, or cooling of the Earth.
 Reference: Best, Elsdon. 1907. Maori Forest Lore: being some
Account of Native Forest Lore and Woodcraft, as also of many Myths, Rites, Customs, and Superstitions connected with the Flora and Fauna of theTuhoe or Ure-wera District.—Part I. Transactions and Proceedings of the New Zealand Institute. Vol. 20, Art. XV, pp. 185-254.