 The earliest known beaked whale fossils date to the Miocene, about 15 million years ago.As many as 26 genera antedate humans.Some included ancestors of giant beaked whales ("Berardius"), such as "Microberardius" and Cuvier's beaked whale ("Ziphius") had many relatives, such as "Caviziphius", "Archaeoziphius", and "Izikoziphius".They were probably preyed upon by predatory whales and sharks, including "Carcharocles megalodon".