Origin of Whales
The marine environment has always been a source of fascination, and there is even greater curiosity with regard to whales because they are animals with unique features and one of the few mammals that have adapted to life in an aquatic environment.
Humpbacks belong to the cetacean group (aquatic mammals from an Order known as Cetartiodactyla), which includes all whale and dolphin species. The Order Cetartiodactyla also includes the artiodactyls (even-toothed ungulates), and the hippopotamus is their closest living relative. The earliest known cetacean fossil is a whale named Pakicetus, an animal with mostly terrestrial characteristics that evolved from ancient artiodactyls and inhabited the a region denominated Tethys Sea around 50 million years ago. The evolutionary transition from land to sea was probably motivated by food scarcity, which led these animals to explore the aquatic environment. Pakicetus gave rise to the prehistoric cetaceans known as archaeocetes, which had characteristics of both terrestrial animals and whales and dolphins. Particularly interesting is the Ambulocetus an intermediate whale considered by many to be the missing link between terrestrial and aquatic cetaceans. Slowly, the evolutionary processes led to the emergence of several new species, such as current-day whales, porpoises and dolphins.