Whales’ ultrasonic hearing has surprisingly ancient history, fossilized ear shows

All living toothed whales rely upon echoes of their own calls to navigate and hunt underwater, a skill that works best in conjunction with high-frequency hearing. Now, researchers studied one of the best-preserved ears of any ancient whale ever discovered find that whales’ high-frequency hearing abilities arose earlier than anticipated.

“Our study suggests that high-frequency hearing may have preceded the emergence of echolocation,” says Morgan Churchill.

Churchill and his colleagues made their discovery in studies of a new fossil whale species (Echovenator sandersi) found in a drainage ditch. The researchers CT scanned the ancient whale’s remarkably complete fossilized ear and compared it to those of two hippos and 23 fossil and living whales. Those analyses uncovered many features found today in dolphins, which can hear at ultrasonic frequencies.

The anatomy of Echovenator’s ear suggests that high-frequency hearing evolved early in whale evolution, about 27 million years ago and that traits associated with this ability actually predate the emergence of toothed whales. It also suggests that the evolutionary ancestors of toothed whales could hear at higher frequencies than their relatives on land.

Churchill says that the inner ear of Echovenator is surprisingly similar to that of modern whales. In fact, only one trait of the ancient whale’s ear was more similar to primitive whales than to modern whales, suggesting a very rapid evolution of hearing abilities in early whales.

Echovenator is remarkable in other ways too, Churchill notes. For instance, the ancient whale was remarkably small compared to its ancestors, suggesting a drastic change in body size early in toothed whale evolution that most likely influenced a range of variables, from brain size to ecology.

Echovenator is just one of many fossil whales. Those fossils represent some of the earliest known ancestors of toothed whales. And that means there’s much more to come on the evolution of intelligence, body size, foraging ecology, and diversity in modern whales.

 

Source: Science daily

N.H.Kh

 

You might also like
Latest news
President of Kosovo after meeting President Al-Sharaa: Kosovo is ready to support the Syrian people Regional Leaders Unite at Antalya Forum: Strengthening Ties Between Syria and Libya with Qatar Suppo... Iraqi Foreign Minister Advocates for Comprehensive Political Solution to Syrian Crisis at Antalya Fo... UNHCR: more than 1.4 million Syrians have returned to their homes since the fall of the regime Meeting Between President Shara’a and President Erdogan Erdogan: Israel's Actions Aim to Destabilize Syria, Turkey Will Not Permit This United Nations Under Secretary General Condemns Israeli Violations in Syrian Golan At the Antalya forum, the Turkish Foreign Minister emphasized the following key points: Qatar Reaffirms Support for Palestinian Resilience at Antalya Diplomatic Forum Turkish President Erdogan at the Antalya Forum: Talks on Cooperation Between Syria and Sweden Held Arab League: Engaging with America to End Israeli Attacks on Syria Turkey: Israeli attacks on Syria are a flagrant violation of its sovereignty and a threat to regiona... Britain at the UN Security Council: We are committed to supporting a comprehensive and prosperous fu... The dignitaries, sheikhs, and intellectuals of the city of Bosra al-Sham issued a statement confirmi... Syrian-Dutch talks on humanitarian support President al-Sharaa extends the mandate of the fact-finding and investigation committee regarding Sy... President Ahmad al-Sharaa meets with members of the fact-finding committee, tasked with investigatin... Lebanese Foreign Minister: Lifting sanctions imposed on Syria will encourage the displaced to return Al-Shibani: Signing agreement with South Korea opens new horizons for cooperation in economy, techno...