of Shiva is relatively rare in Shaivism compared to the well emphasized concept of Vishnu avatars in Vaishnavism. Some Vaishnava literature reverentially link Shiva to characters in its Puranas. For example, in the Hanuman Chalisa, Hanuman is identified as the eleventh avatar of Shiva. The Bhagavata Purana and the Vishnu Purana claim sage Durvasa to be a portion of Shiva. Some medieval era writers have called the Advaita Vedanta philosopher Adi Shankara an incarnation of Shiva. Temple Festivals There is a Shivaratri in every lunar month on its 13th night/14th day, but once a year in late winter (February/March) and before the arrival of spring, marks Maha Shivaratri which means "the Great Night of Shiva". Maha Shivaratri is a major Hindu festival, but one that is solemn and theologically marks a remembrance of "overcoming darkness and ignorance" in life and the world, and meditation about the polarities of existence, of Shiva and a devotion to humankind. It is observed by reciting Shiva-related poems, chanting prayers, remembering Shiva, fasting, doing Yoga and meditating on ethics and virtues such as self-restraint, honesty, noninjury to others, forgiveness, introspection, self-repentance and the discovery of Shiva. The ardent devotees keep awake all night. Others visit one of the Shiva temples or go on pilgrimage to Jyotirlingam shrines. Those who visit temples, offer milk, fruits, flowers, fresh leaves and sweets to the lingam. Some communities organize special dance events, to mark Shiva as the lord of dance, with individual and group performances. According to Jones and Ryan, Maha Sivaratri is an ancient Hindu festival which probably originated around the 5th-century. Another major festival involving Shiva worship is Kartik Purnima, commemorating Shiva's victory over the three demons known as Tripurasura. Across India, various Shiva temples are illuminated throughout the night. Shiva icons are carried in procession in some places. Thiruvathira is a festival observed in Kerala dedicated to Shiva. It is believed that on this day, Parvati met Shiva after her long penance and Shiva took her as his wife. On this day Hindu women performs the Thiruvathirakali accompanied by Thiruvathira paattu (folk songs about Parvati and her longing and penance for Shiva's affection). Regional festivals dedicated to Shiva include the Chithirai festival in Madurai around April/May, one of the largest festivals in South India, celebrating the wedding of Minakshi (Parvati) and Shiva. The festival is one where both the Vaishnava and Shaiva communities join the celebrations,