Descending from creatures that were terrestrial and then amphibious before they were aquatic, cetaceans (whales, dolphins and porpoises) possess some of the animal kingdom’s most fascinating evolutionary histories. This video from the UK artist Jordan Collver traces the evolution of the sperm whale from the amphibious Pakicetus to its present form. After depicting six distinct points in evolutionary history, Collver morphed his still illustrations into one another, incrementally, over ten minutes. The resulting animation, Whalevolution, emphasises that a single strand of evolutionary history isn’t characterised by a series of distinct species, but rather, as Charles Darwin put it, an ‘infinitude of connecting links’. You can find an abridged 25-second version of the animation here, and Collver’s six original illustrations here.