Artwork of pterosaurs flying over a scene of destruction. Some 65 million years ago, the impact of an asteroid or comet with the Earth provoked one of prehistory's greatest mass-extinctions, when it wiped out the dinosaurs, pterosaurs and many other species. The impact occurred in a shallow sea, off the coast of what is now Mexico, caving out a magma-filled wound some 180 kilometres across. Ejecta was thrown high into the atmosphere. The dust remained there for years, blocking out the Sun's light-giving rays. The heavier ejecta fell to earth in a torrent of molten rocks, hundreds of kilometres from ground zero. Here, pteranodons - flying reptiles - are seen fleeing the onslaught, which has already set fire to the forest behind them.