Nuralagus rex lived in the Late Neogene, which ended about 2.5m years ago, and was 10 times the size of extant rabbits, weighing an estimated average of 12 kg.

The small skull of Nuralagus, which lived on Menorca, suggests dramatic decreases in hearing, sight, and motor-related abilities compared to typical rabbits. Because it had no known predators, there was no selection for detecting or outrunning them. The lagomorph, the largest ever seen, appears to have had reduced aerobic capacity and to have walked slowly rather than jumped quickly.

Like Charles Darwin's Galapagos, many islands are superb evolutionary laboratories. In this case, the absence of typical predators accelerated speciation. Nuralagus rex reminds us that every species, even those long dead, has something to teach us.

The fossil was described and named by Meike Köhler and Salvador Moyà-Solà of the Institut Català de Paleontologia in Barcelona.

Quentin Wheeler is director of the International Institute for Species Exploration, Arizona State University