Featured Research

from universities, journals, and other organizations

Unusual anal fin offers new insight into evolution

Date:
April 10, 2013
Source:
Manchester University
Summary:
An unusual fossil fish that has fins behind its anus could have implications for human evolution.

Euphanerops with the anal fins visible near the tail.
Credit: Biology Letters

An unusual fossil fish that has fins behind its anus could have implications for human evolution according to a scientist at The University of Manchester.

Related Articles


Dr Robert Sansom from the Faculty of Life Sciences identified the paired fins of Euphanerops, a fossil jawless fish that swam in the seas around 370 million years ago. The find makes the fish one of the first vertebrate to develop paired appendages such as fins, legs or arms.

However, their positioning is incredibly unusual, as Dr Sansom explains: "Euphanerops is unique because its anal fin is paired meaning there is one fin on each side of the fish. Up until now anal fins have only been seen on jawed fish where they are unpaired and this is true of both extinct and modern fish. The age of Euphanerops is important as it dates from the time of a deep evolutionary split between jawed and jawless fish, the two main divisions of vertebrates alive today. As such, it represents an important stage in the evolution of paired appendages."

He continues: "It's not clear why the fins are positioned so far back on the fish, or what advantage they might have provided. However, they do show that our early vertebrate ancestors tried out lots of different body plans before settling on two arms and two legs. If they hadn't then our bodies would have looked very different!"

Dr Sansom came across the paired fins as part of a study of Euphanerops fossils in Quebec, Canada. 3D surface scans of fossils and comparison of specimens preserved in different conditions revealed that there were two fan-shaped fins, a left and a right.

Dr Sansom's research on the paired fins followed on from a 2009 study of early vertebrate evolution and fossil preservation with colleagues from The University of Leicester. Their findings have been published in the Royal Society's journal Biology Letters.

Dr Sansom says it was an exciting find: "The unusual paired anal fin of Euphanerops lends support to the idea that there was some degree of developmental and evolutionary experimentation in some fish. After the Devonian period and the extinction of a lot of species, the jawed vertebrate body exhibits fewer deviations from the formula of paired pectoral, paired pelvic, unpaired dorsal and unpaired anal appendages. The discovery of new anatomical conditions will hopefully shed more light on the timing and sequence of the events underlying the origin and diversification of vertebrate appendages."


Story Source:

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


Journal Reference:

  1. R. S. Sansom, S. E. Gabbott, M. A. Purnell. Unusual anal fin in a Devonian jawless vertebrate reveals complex origins of paired appendages. Biology Letters, 2013; 9 (3): 20130002 DOI: 10.1098/rsbl.2013.0002

Cite This Page:

Manchester University. "Unusual anal fin offers new insight into evolution." ScienceDaily. ScienceDaily, 10 April 2013. <www.sciencedaily.com/releases/2013/04/130410082201.htm>.
Manchester University. (2013, April 10). Unusual anal fin offers new insight into evolution. ScienceDaily. Retrieved January 30, 2015 from www.sciencedaily.com/releases/2013/04/130410082201.htm
Manchester University. "Unusual anal fin offers new insight into evolution." ScienceDaily. www.sciencedaily.com/releases/2013/04/130410082201.htm (accessed January 30, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Brawling Pandas Are Violently Adorable

Brawling Pandas Are Violently Adorable

Buzz60 (Jan. 29, 2015) Video of pandas play fighting at the Chengdu Research Base in China will make your day. Mara Montalbano (@maramontalbano) shows us. Video provided by Buzz60
Powered by NewsLook.com
Why Researchers Say We Should Cut Back On Biofuels

Why Researchers Say We Should Cut Back On Biofuels

Newsy (Jan. 29, 2015) Biofuels aren&apos;t the best alternative to fossil fuels, according to a new report. In fact, they&apos;re quite a bad one. Video provided by Newsy
Powered by NewsLook.com
3-D Printed Wheelchair Helps Two-Legged Dog Learn to Run

3-D Printed Wheelchair Helps Two-Legged Dog Learn to Run

Buzz60 (Jan. 29, 2015) 3-D printing helps another two-legged dog run around with his four-legged friends. Jen Markham (@jenmarkham) has the adorable video. Video provided by Buzz60
Powered by NewsLook.com
Dogs Bring on So Many Different Emotions in Their Human Best Friends

Dogs Bring on So Many Different Emotions in Their Human Best Friends

RightThisMinute (Jan. 28, 2015) From new-puppy happy tears to helpful-grocery-carrying-dog laughter, our four-legged best friends can make us feel the entire spectrum of emotions. Video provided by RightThisMinute
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