Featured Research

from universities, journals, and other organizations

Researchers Discover Clues To Whale Evolution

Date:
May 10, 2002
Source:
National Science Foundation
Summary:
A team of international scientists, including Hans Thewissen, an anatomist and paleontologist at the Northeastern Ohio Universities College of Medicine (NEOUCOM), has discovered that the inner ear of whales evolved much more quickly than expected, allowing the animals to become fully aquatic early in their evolution. The team’s research, funded by the National Science Foundation (NSF), shows that the semicircular canals, the organ responsible for balance and located in the inner ear, was adapted to aquatic life approximately 45 million years ago.

A team of international scientists, including Hans Thewissen, an anatomist and paleontologist at the Northeastern Ohio Universities College of Medicine (NEOUCOM), has discovered that the inner ear of whales evolved much more quickly than expected, allowing the animals to become fully aquatic early in their evolution. The team’s research, funded by the National Science Foundation (NSF), shows that the semicircular canals, the organ responsible for balance and located in the inner ear, was adapted to aquatic life approximately 45 million years ago. The discovery will be published in the May 9 issue of the journal Nature.

Related Articles


Cetaceans (whales, dolphins and porpoises) have unique semicircular canals that allow them to be highly acrobatic swimmers without becoming dizzy. By investigating this organ in ancient fossils, the researchers found that early whales acquired this special trait quickly and early on in their evolution. This was a defining event that likely resulted in their total independence of life on land.

“The early evolutionary development of small semicircular canals by cetaceans opened an entirely new mammalian niche for habitation and contributed to the broad diversity of marine living habits that we see in whales today,” said Rich Lane, director of NSF’s paleontology program, which funded the research. “The evolutionary acquisition of such specialized organs or abilities (like the brain and upright walking habit of man) provide mechanisms by which highly evolved organisms dominate in certain environments.”

The semicircular canals sense head movements and this vital information is used to coordinate the body during locomotion. This happens subconsciously, and humans only become aware of an organ of balance when things go wrong, such as during sea sickness, drunkenness and wild roller coaster rides.

The researchers found that in living cetaceans the semicircular canals are much smaller than in any other mammal of the same body size. In fact, the semicircular canals of the huge blue whale are smaller than those of humans. In general, cetaceans are more acrobatic than similarly sized land animals (imagine an elephant making the jumps of a similar-sized whale). This could be the result of the small canals, because the small size makes the canals less sensitive, preventing the animal from becoming dizzy (i.e. experiencing vertigo).

Between 40 and 50 million years ago, early cetaceans evolved from land mammals into swimmers. Over the last decade many new whale fossils have been found which show how this dramatic change happened. Skeletons of the transitional species (“whales with limbs”) demonstrate that they were adept, otter-like swimmers.

Just last year, Thewissen’s discovery of two early whale ancestors showed that the earliest whales were mainly land animals, and resolved a controversy over the relationships of whales, showing that they are most closely related to modern even-toed ungulates (such as pigs, hippos, camels, deer, and sheep) than to an extinct group of meat-eating mammals.


Story Source:

The above story is based on materials provided by National Science Foundation. Note: Materials may be edited for content and length.


Cite This Page:

National Science Foundation. "Researchers Discover Clues To Whale Evolution." ScienceDaily. ScienceDaily, 10 May 2002. <www.sciencedaily.com/releases/2002/05/020509073449.htm>.
National Science Foundation. (2002, May 10). Researchers Discover Clues To Whale Evolution. ScienceDaily. Retrieved October 26, 2014 from www.sciencedaily.com/releases/2002/05/020509073449.htm
National Science Foundation. "Researchers Discover Clues To Whale Evolution." ScienceDaily. www.sciencedaily.com/releases/2002/05/020509073449.htm (accessed October 26, 2014).

Share This



More Plants & Animals News

Sunday, October 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins