Interested in knowing about the grandfather of the demon King Ravana? Or may be his children?Ravana, the archetypical 'Rakshasa,' was a gentleman ogre and son of a Brahmin, a great scholar of Sanskrit and devout worshipper of Lord Shiva and if author Nandita Krishna, a Chennai-based historian and environmentalist is to be believed, Lord Rama and Ravana did exist."The story 'Ramayana' is graphically very correct besides which there are any number of local traditions and temples all along Lord Rama's route.It is unlikely that 3000 years ago somebody could have traveled around the country inventing local traditions regarding Lord Rama's visit," Krishna says in her book 'The Book of Demons, Including a dictionary of demons and Sanskrit Literature.' "The discovery of a man-made shoal bridge in the Palk Strait between India and Sri Lanka is also significant," the author says.Sri Lanka also has local traditions such as the cave at Ravana Ella falls where Ravana is believed to have hidden Sita from and the garden of Asoka trees where Ravana once kept Sita prisoner. There is a record in an early issue of the Bellary District Gazetteer of a Vanara tribe in the region, she says.From the Rig Veda to myriad of folk narratives, the belief in demons prevails all over India, says Krishna, who is also Director of CP Ramaswami Institute of Indological Research, Chennai. "Male or female, human, animal, plant or simply a concept, demons play a pivotal role in the country's mythical traditions" she says.The author thus tells about Gajamukha, the elephant-faced demon who was transformed into a mouse by Lord Ganesha and then converted into his vehicle.