August 6, 2016
Porpoises, dolphins, orcas, and other toothed whales notably have a way to ‘see’ in the dark foggy depths or the cloudy shallows of the ocean, where visibility level is nearly zero and obstacles, predators, or tasty prey can’t be seen.
The toothed whales are scientifically known as odontocetes. They use echolocation, make sounds and hear how the emitted sounds echo back to map their surroundings. Their auditory map has finer details because the whales emit sounds at a specifically high frequency.
Now researchers have come to know that the special hearing has been there in toothy marine mammals for a remarkably long time. A group of researchers has discovered that the inner ear of Echovenator sandersi, an odontocete that was present on our planet 27 million years back, looked much like the existing toothed whales.
Study lead author Morgan Churchill of the New York Institute of Technology said, “What this shows is that you get fairly advanced echolocation and ultrasonic hearing abilities right at the base of the evolution of all these toothed whales”.
Erich Fitzgerald, senior curator of vertebrate paleontology at the Museum Victoria in Melbourne, Australia said that the latest study hasn’t come all of a sudden and that too from nowhere. Fitzgerald wasn’t a part of the study.
In a 2014 study, researchers discovered a proof in a 28-million-year-old fossil that toothed whales can possibly create the high-frequency noise used in echolocation. In April 2016, Dr. Fitzgerald’s own research got published, which discovered that a 26-million-year-old whale may have the ability to hear that high-pitched sound as it echoed back.
Even then, as per Fitzgerald, the latest study has analyzed superb fossils from South Carolina, offering yet more convincing support for the belief that the echolocation, or sonar, of killer whales, porpoises, and living dolphins can be traced right back over 25 million years back, their initial days.