"Aitareya Brahmana", an early text, describes the Nishadas as raiders operating in the forests. However, the later Shrauta texts suggest that they were gradually assimilated into the Indo-Aryan society, and were not considered as untouchable at this time. For example:   These references suggest that the Indo-Aryans made efforts to assimilate the Nishadas into their own social order, but the Vedic ritual status granted to the Nishadas was limited in nature. Historian Ramaprasad Chanda speculates that the Nishadas were too numerous and too powerful to be eliminated, enslaved, or expelled by the Indo-Aryans: this may explain the limited attempts to assimilate them. It is possible that only the high-class among the Nishadas were inducted into the Indo-Aryan society, while the majority of them remained unassimilated. Panini's "Ganapatha" mentions a gotra called Nishada, which according to scholar D. D. Kosambi, suggests that some tribal priests were assimilated as Brahmanas in the Indo-Aryan society. The "Rudra Adhyaya" of the ancient "Yajurveda" "Samhita" shows reverence to the Nishadas, among others. Nevertheless, the Nishadas held a low status in the Indo-Aryan society:   In what appears to be an attempt to define the status of the Nishadas in the varna system, several ancient texts present them as progeny of parents from different varnas. This appears to have been done for legal purposes, since a person's varna status determined how the contemporary law treated them. For example:   Gradually, the Nishadas were relegated to the status of untouchables in the Indo-Aryan society. The main profession of Nishaadas was fishing and hunting. When a Nishaada had killed one bird from a pair, the other bird was remorseful of its loss and was in pangs of pain, observing this deep pain inspired the sage Valmiki to write the life history of king Rama of Ayodhya and his dutiful wife queen Sita, who lived in separation due to her capture by deceit by the egoistic demon-like king Ravana. This poetic mythology is revered in India as a guide to highest ideals of human-life, is known as the Ramayana, or the record of king Rama's life. In Ramayana, the king of Nishaadas, named Guha, was a very close friend of Rama.