Featured Research

from universities, journals, and other organizations

Dawn Of Animal Vision Discovered

Date:
October 18, 2007
Source:
University of California - Santa Barbara
Summary:
By peering deep into evolutionary history, scientists have discovered the origins of photosensitivity in animals. The researcher said that anti-evolutionists often argue that mutations, which are essential for evolution, can only eliminate traits and cannot produce new features. He goes on to say, "Our paper shows that such claims are simply wrong. We show very clearly that specific mutational changes in a particular duplicated gene (opsin) allowed the new genes to interact with different proteins in new ways. Today, these different interactions underlie the genetic machinery of vision, which is different in various animal groups."

Opsin genes (blue) are present and expressed in the cnidarian Hydra.
Credit: David Plachetzki/UCSB

By peering deep into evolutionary history, scientists at the University of California, Santa Barbara have discovered the origins of photosensitivity in animals.

The scientists studied the aquatic animal Hydra, a member of Cnidaria, which are animals that have existed for hundreds of millions of years. The authors are the first scientists to look at light-receptive genes in cnidarians, an ancient class of animals that includes corals, jellyfish, and sea anemones.

"Not only are we the first to analyze these vision genes (opsins) in these early animals, but because we don't find them in earlier evolving animals like sponges, we can put a date on the evolution of light sensitivity in animals," said David C. Plachetzki, first author and a graduate student at UC Santa Barbara. The research was conducted with a National Science Foundation dissertation improvement grant.

"We now have a time frame for the evolution of animal light sensitivity. We know its precursors existed roughly 600 million years ago," said Plachetzki.

Senior author Todd H. Oakley, assistant professor of biology at UCSB, explained that there are only a handful of cases where scientists have documented the very specific mutational events that have given rise to new features during evolution.

Oakley said that anti-evolutionists often argue that mutations, which are essential for evolution, can only eliminate traits and cannot produce new features. He goes on to say, "Our paper shows that such claims are simply wrong. We show very clearly that specific mutational changes in a particular duplicated gene (opsin) allowed the new genes to interact with different proteins in new ways. Today, these different interactions underlie the genetic machinery of vision, which is different in various animal groups."

Hydras are predators, and the authors speculate that they use light sensitivity in order to find prey. Hydra use opsin proteins all over their bodies, but they are concentrated in the mouth area, near the tip of the animal. Hydras have no eyes or light-receptive organs, but they have the genetic pathways to be able to sense light.

The findings are published in PLoS One. Co-author Bernie M. Degnan, of the University of Queensland in Brisbane, Australia, provided bioinformatics tools to complete the study.


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Santa Barbara. "Dawn Of Animal Vision Discovered." ScienceDaily. ScienceDaily, 18 October 2007. <www.sciencedaily.com/releases/2007/10/071016205858.htm>.
University of California - Santa Barbara. (2007, October 18). Dawn Of Animal Vision Discovered. ScienceDaily. Retrieved August 31, 2014 from www.sciencedaily.com/releases/2007/10/071016205858.htm
University of California - Santa Barbara. "Dawn Of Animal Vision Discovered." ScienceDaily. www.sciencedaily.com/releases/2007/10/071016205858.htm (accessed August 31, 2014).

Share This




More Fossils & Ruins News

Sunday, August 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Millions Of Historical Public Domain Photos Added To Flickr

Millions Of Historical Public Domain Photos Added To Flickr

Newsy (Aug. 30, 2014) Historian Kalev Leetaru uploaded a large collection of historical photos, images that were previously difficult to collect. Video provided by Newsy
Powered by NewsLook.com
Minds Blown: Scientists Develop Fish That Walk On Land

Minds Blown: Scientists Develop Fish That Walk On Land

Newsy (Aug. 28, 2014) Canadian scientists looking into the very first land animals took a fish out of water and forced it to walk. Video provided by Newsy
Powered by NewsLook.com
Huge Ancient Wine Cellar Found In Israel

Huge Ancient Wine Cellar Found In Israel

Newsy (Aug. 28, 2014) An international team uncovered a large ancient wine celler that likely belonged to a Cannonite ruler. Video provided by Newsy
Powered by NewsLook.com
40,000-Year-Old Mammoth Skeleton Found On Texas Farm

40,000-Year-Old Mammoth Skeleton Found On Texas Farm

Newsy (Aug. 26, 2014) A mammoth skeleton was discovered in a gravel pit on Wayne McEwen's Texas farm back in May. It's now being donated to a museum. 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:
from the past week

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