Sperm and Beaked Whales, Evolution

Although extant sperm whales (Kogiidae and Physeteridae) and beaked whales (Ziphiidae) share a series of ecological and morphological traits, the continuously improving fossil record yields stem taxa whose foraging strategies and paleoecology are hypothesized to differ markedly from modern species: extinct macroraptorial sperm whales and raptorial snapping beaked whales, most likely feeding on epipelagic prey. The available paleontological data suggest the parallel progressive emergence, in physeteroids and ziphiids, of characters related to a specialization toward deep diving and suction feeding.