Confined to bed with eczema in 1863, Charles Darwin spent weeks watching climbing plants in his room, after reading a paper by the American botanist Asa Gray on touch-sensitive tendrils. He saw that the tips of growing shoots and tendrils sweep around in constant circles, tracing spirals that bring them into contact with anything they can climb. He called these 'spontaneous revolutions' circumnutation. To make them visible, he recorded the path of plant tips on glass with ink dots, creating diagrams of plant movement. Nearly two decades later he published The Power of Movement in Plants (1880).

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.