A new fossil species supports an early origin for toothed whale echolocation.

Odontocetes (toothed whales, dolphins and porpoises) hunt and navigate through dark and turbid aquatic environments using echolocation; a key adaptation that relies on the same principles as sonar. Among echolocating vertebrates, odontocetes are unique in producing high-frequency vocalizations at the phonic lips, a constriction in the nasal passages just beneath the blowhole, and then using air sinuses and the melon to modulate their transmission. All extant odontocetes seem to echolocate; however, exactly when and how this complex behaviour--and its underlying anatomy--evolved is largely unknown.