Sand and wind are engaged in a perpetual play. In deserts, where sand is present in abundance and wind can flow freely, they get very sportive. As they roll and bounce, desert dunes are formed. For scientists and researchers all over the world, the subject of desert dunes is an interesting domain. But as they explore it, its complexity increases. There was a time when very little was known about them. But now, with a lot of research going on, scientists have uncovered many amazing facts about their structure, formation, existence, and behaviour. In fact, the way desert dunes behave is now believed to be more than a subject of Geology or Physics. On the outside, they may seem like inanimate grains of sand but studies have shown that they are something more than dead sand grains. They evolve, move, sing, breathe, and also communicate with one other! How and where do desert dunes travel? Does this make any difference to the earth’s ecosystem? What are the adverse effects of desert dunes? Explore the complex behaviour of desert dunes and their impact on the earth, in this module.