Scientists from the New York Institute of Technology have discovered fossil evidence showing that ancient species of whales were capable of echolocation millions of years ago.
The fossil was from a creature called Cotylocara macei, a whale that thrived 28 million years ago and closely resembled bottleneck dolphins. The remains of the Cotylocara were found in Summerville, South Carolina by geologist James Carew of the New York Institute of Technology. The fossils included a 22-inch skull, ribs, and neck vertebrae. The discovery reflected that the echolocation was used by toothed whales for centuries, probably around 32 to 34 million years ago.
Toothed whales started using echolocation some years after whales split into two major groups. One is the toothed whale, the family where sperm whales, dolphins, killer whales and porpoises belong to and the other family is the toothless baleen whales which use filter feeding for survival.
Anatomy professor from the New York Institute of Technology, Jonathan Geisler stated that the whale's use of echolocation is "an amazing trait".
"It's a sonar-like system which allows them basically to navigate and find food, particularly in waters where there's little light, either at great depth or in very turbulent waters with a lot of mud, like estuaries or around marshes," Geisler told Reuters.
Echolocation was produced by whales when they use high-frequency sounds through the nasal passage between their blowhole and the skull. As the sound was produced, the frequency bounces off objects in their surroundings that serve as audio-images of their path.
The whales living today have a melon-like organ in their heads, filled with fat, and this helps them focus and produce sound waves. According to Geisler, the Cotylocara may have possessed this organ, as well.
Echolocation is not exclusive to whales. There are other species that use echolocation to move around, including bats.
This study was published in the March 12 issue of Nature.
