Previously, the earliest known toothed whale
that may have used sonar to hunt was 32 million years old, but the evidence wasn't definitive.
dive deep into the ocean in search of food.
Among toothed whales
, the sperm whale (Physeter catodon or Physeter macrocephalus) is the biggest, reaching a length of about 60 feet.
About 1,100 species of bats and roughly 80 species of toothed whales
use the technique - this is 25 percent of all living species of mammals.
eat animals such as penguins, seals, and large fish.
are deep divers that hunt for food using echolocation--they emit sounds that bounce off objects and return to the whale, giving a "picture" of the preys shape, size, and whereabouts.
Also, the frequency is too low to be heard well by most ocean echolocators--the dolphins and toothed whales
that use sound to navigate and find food.
Paleontologists have long thought that Mysticetes and Odontocetes represent separate evolutionary lines that split from a group of ancestral toothed whales
some 40 million years ago.
, on the other hand, include animals that are classically identified as whales - like the sperm whale and the orca, also known as the (http://www.
Felix Marx has worked primarily on the fossil record of the earliest baleen whales (mysticetes), while Olivier Lambert has studied principally the fossils of extinct toothed whales
The sperm whales, members of Earth's largest species of toothed whales
, were originally spotted by fishermen in Tyre early Thursday morning.
At a special kiosk, visitors can listen to clips of several species, as well as the screech of sonar, which is thought to disrupt navigation of toothed whales
and has been linked to mass strandings.