Featured Research

from universities, journals, and other organizations

Mystery of the flatfish head solved

Date:
June 25, 2012
Source:
Federation of American Societies for Experimental Biology
Summary:
A new discovery describes a fossil fish, named Heteronectes (meaning "different swimmer") that was found in 50 million year old marine rocks from northern Italy. This study provides the first detailed description of a primitive flatfish, revealing that the migrated eye had not yet crossed to the opposite side of the skull in early members of this group.

This is the skeleton of the primitive flatfish Heteronectes shown as an x ray image (top), photograph before preparation (middle), and photograph after preparation (bottom).
Credit: Image by M. Friedman

Those delicious flatfishes, like halibut and sole, are also evolutionary puzzles. Their profoundly asymmetrical heads have one of the most unusual body plans among all backboned animals (vertebrates) but the evolution of their bizarre anatomy has long been a mystery. How did flatfishes, with both of their eyes on one side of their head, evolve? So puzzling was the anatomy of flounders and their kin that they were used in early arguments against Darwin and his theory of natural selection. Skeptics wondered how such unusual features could have slowly evolved whilst remaining advantageous for the fishes' survival.

A new fossil discovery described in the latest issue of the Journal of Vertebrate Paleontology by Oxford University researcher Dr Matt Friedman finally solves the mystery. Friedman's fossil fish, named Heteronectes (meaning 'different swimmer'), was found in 50 million year old marine rocks from northern Italy. This study provides the first detailed description of a primitive flatfish, revealing that the migrated eye had not yet crossed to the opposite side of the skull in early members of this group. Heteronectes, with its flattened form, shows the perfect intermediate stage between most fish with eyes on each side of the head and specialized flatfishes where both eyes are on the same side.

"This fossil comes from Bolca in northern Italy, a site that has literally been mined for hundreds of years for its fossil fishes. This remarkable site provides a snapshot of an early coral reef assemblage. Reefs are well known as biodiversity hotspots, so it is perhaps not surprising that Bolca provides us with the first evidence of many modern fish groups," said Friedman. "Our understanding of the relationships of some of these groups is in a state of change with the increasing influx of molecular genetic studies. Fossils have not contributed very much to this debate, but specimens like that of Heteronectes reveal the superb level of detail that can be extracted from extinct species."

Friedman noted that "The specimen itself was discovered -- with no identification -- in a museum collection in Vienna. It just goes to show that even well-known fossil sites can yield important surprises, and that not all new discoveries take place in the field."

"This is a profound discovery which clearly shows that intermediate fossil forms, which according to certain creationist theories shouldn't exist, are regularly turning up as scientists keep looking for them," says Dr. John Long of the Natural History Museum of LA County, an expert in fossil fishes who was not involved in the study.


Story Source:

The above story is based on materials provided by Federation of American Societies for Experimental Biology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Friedman, M. Osteology of †Heteronectes chaneti (Acanthomorpha, Pleuronectiformes), an Eocene stem flatfish, with a discussion of flatfish sister-group relationships. Journal of Vertebrate Paleontology, 2012; (32)4: 735-756

Cite This Page:

Federation of American Societies for Experimental Biology. "Mystery of the flatfish head solved." ScienceDaily. ScienceDaily, 25 June 2012. <www.sciencedaily.com/releases/2012/06/120625160358.htm>.
Federation of American Societies for Experimental Biology. (2012, June 25). Mystery of the flatfish head solved. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2012/06/120625160358.htm
Federation of American Societies for Experimental Biology. "Mystery of the flatfish head solved." ScienceDaily. www.sciencedaily.com/releases/2012/06/120625160358.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
Argentina Worries Over Decline of Soybean Prices

Argentina Worries Over Decline of Soybean Prices

AFP (Sep. 27, 2014) The drop in price of soy on the international market is a cause for concern in Argentina, as soybean exports are a major source of income for Latin America's third largest economy. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Mama Bear, Cubs Hang out in California Backyard

Mama Bear, Cubs Hang out in California Backyard

Reuters - US Online Video (Sep. 27, 2014) A mama bear and her two cubs climb trees, wrestle and take naps in the backyard of a Monrovia, California home. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
'Crazy' Climate Forces Colombian Farmers to Adapt

'Crazy' Climate Forces Colombian Farmers to Adapt

AFP (Sep. 26, 2014) Once upon a time, farming was a blissfully low-tech business on Colombia's northern plains. Duration: 02:05 Video provided by AFP
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