The history of Indian cuisine consists of cuisine from the Indian subcontinent, which is rich and diverse. The diverse climate in the region, ranging from deep tropical to alpine, has also helped considerably broaden the set of ingredients readily available to the many schools of cookery in India. In many cases, food has become a marker of religious and social identity, with varying taboos and preferences (for instance, a segment of the Jain population consume no roots or subterranean vegetable; see Jain vegetarianism) which has also driven these groups to innovate extensively with the food sources that are deemed acceptable.