 Recently, a large fossil ziphiid sample was discovered off the South African coast, confirming the extant ziphiid diversity might just be a remnant of a higher past diversity.After studying numerous fossil skulls off the shore of South Africa, researchers discovered the absence of functional maxillary teeth in all South African fossil ziphiids, which is evidence that suction feeding had already developed in several beaked whale lineages during the Miocene.Researchers also found fossil ziphiids with robust skulls, signaling that tusks were used for male-male interactions (speculated with extant beaked whales).