Science News
from research organizations

New study sheds light on how and when vision evolved

Date:
October 29, 2012
Source:
University of Bristol
Summary:
Opsins, the light-sensitive proteins key to vision, may have evolved earlier and undergone fewer genetic changes than previously believed, according to a new study.
Share:
         
Total shares:  
FULL STORY

The eye of a cuttlefish.
Credit: Image courtesy of University of Bristol

Opsins, the light-sensitive proteins key to vision, may have evolved earlier and undergone fewer genetic changes than previously believed, according to a new study from the National University of Ireland Maynooth and the University of Bristol published October 29 in Proceedings of the National Academy of Sciences (PNAS) .

The study, which used computer modelling to provide a detailed picture of how and when opsins evolved, sheds light on the origin of sight in animals, including humans. The evolutionary origins of vision remain hotly debated, partly due to inconsistent reports of phylogenetic relationships among the earliest opsin-possessing animals.

Dr Davide Pisani of Bristol's School of Earth Sciences and colleagues at NUI Maynooth performed a computational analysis to test every hypothesis of opsin evolution proposed to date. The analysis incorporated all available genomic information from all relevant animal lineages, including a newly sequenced group of sponges (Oscarella carmela) and the Cnidarians, a group of animals thought to have possessed the world's earliest eyes.

Using this information, the researchers developed a timeline with an opsin ancestor common to all groups appearing some 700 million years ago. This opsin was considered 'blind' yet underwent key genetic changes over the span of 11 million years that conveyed the ability to detect light.

Dr Pisani said: "The great relevance of our study is that we traced the earliest origin of vision and we found that it originated only once in animals. This is an astonishing discovery because it implies that our study uncovered, in consequence, how and when vision evolved in humans."


Story Source:

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


Journal Reference:

  1. Roberto Feuda, Sinead C. Hamilton, James O. McInerney, and Davide Pisani. Metazoan opsin evolution reveals a simple route to animal vision. PNAS, October 29, 2012 DOI: 10.1073/pnas.1204609109

Cite This Page:

University of Bristol. "New study sheds light on how and when vision evolved." ScienceDaily. ScienceDaily, 29 October 2012. <www.sciencedaily.com/releases/2012/10/121029154324.htm>.
University of Bristol. (2012, October 29). New study sheds light on how and when vision evolved. ScienceDaily. Retrieved April 26, 2015 from www.sciencedaily.com/releases/2012/10/121029154324.htm
University of Bristol. "New study sheds light on how and when vision evolved." ScienceDaily. www.sciencedaily.com/releases/2012/10/121029154324.htm (accessed April 26, 2015).

Share This Page:


Plants & Animals News
April 26, 2015

Latest Headlines
updated 12:56 pm ET