A yawn is a reflex found in nearly all vertebrates, from mammals and birds to reptiles, amphibians and fish. It involves a long inhale with the mouth wide open, a brief stretch at the peak, and a quick exhale, and the airway widens to three or four times its normal size. In humans, a yawn is often triggered just by seeing or hearing someone else yawn, a form of echopraxia that also appears in chimpanzees, dogs and cats. Yawns happen most before and after sleep, during boredom and when tired. About twenty explanations have been proposed, from cooling the brain to increasing alertness, but none has won general agreement.

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.