Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The aye-ayes have it: The preservation of color vision in a creature of the night

05.09.2007
A quest to gain a more complete picture of color vision evolution has led Biodesign Institute researcher Brian Verrelli to an up-close, genetic encounter with one of the world’s most rare and bizarre-looking primates.

Verrelli and his ASU team have performed the first sweeping study of color vision in the aye-aye (pronounced “eye-eye”), a bushy-tailed, Madagascar native primate with a unique combination of physical features including extremely large eyes and ears, and elongated fingers for reaching hard to access insects and other foods.

Verrelli, lead author George Perry, and collaborator Robert Martin’s results, published in the journal Molecular Biology and Evolution, have led to some surprising conclusions on how this nocturnal primate may have retained color vision function.

Verrelli’s group focuses on color vision to better understand genetic variation between human and other primate populations and the truly big evolutionary questions as to what makes us human. “At least within humans and some other primates, we know that there are three different genes responsible for color vision,” said Verrelli. The genes, called opsins, come in three forms that shape our color vision palette, one for blue, another for green, and a third for red.

... more about:
»Genetic »Verrelli »aye-aye »endangered »nocturnal »opsin »primate

“What makes that very interesting is that the green and red are found on the X chromosome [sex chromosome], and it is the manipulation of those two genes alone which is related to color blindness for eight to ten percent of the male population,” explains Verrelli. In a 2004 study in the American Journal of Human Genetics by Verrelli and collaborator Sarah Tishkoff of the University of Maryland, they suggested that natural genetic selection has provided women with a frequent ability to better discriminate between colors than men.

“These three genes may explain all the variation that we might see across human populations in color vision,” said Verrelli. “But how did our range of color vision variation come to be in the first place"”

To help trace back the evolution of color vision, Verrelli’s collaborator Perry turned to the endangered aye-aye, a primate representative of lemurs. These primates split from other groups including humans, apes, and monkeys more than sixty million years ago, and are thought to be in some ways representative of the early primates that lived at that time. “We chose the aye-aye specifically because it has a very interesting behavior in that it is fully nocturnal, and so, it raises an obvious and straightforward question: If you are an animal that lives at night, do you need color vision"”

In a simple case of ‘use it or lose it,’ the prevailing theory suggested that nocturnal primates cannot use color vision to see, and so the genes that they have for color vision accumulated mutations and degraded over evolutionary time.

From a practical standpoint, studying color vision in the aye-aye proved to be a daunting endeavor. Since the aye-aye is an endangered species, obtaining DNA samples in the wild was not possible. The group turned to a few rare international research institutions and colleagues that have aye-ayes to obtain DNA samples for their study.

In all total, they obtained samples from eight aye-ayes for their study. It took a year and a half to analyze the samples, since Perry and Verrelli had to invent the methodology to perform the first wide-range genetic analysis on the aye-aye. “From a conservation, population and functional viewpoint, it was the first study of its kind,” said Verrelli.

The results his team found were so startling that they had to recheck them twice. “When examining these genes in the aye-aye, we realized that they are not degrading,” said Verrelli. “In fact, for the green opsin gene, we did not find a single mutation in it. The opsin genes look to be absolutely fully functional, which is completely counter to how we had believed color vision evolved in nocturnal mammals.”

The authors plan to collaborate with others to perform behavioral studies to see if aye-ayes can respond to colors and further molecular studies to identify the exact color absorption by the opsin proteins to see how this may differ from other primates that are not nocturnal.

The study has not only proved important to understanding color vision evolution, but also has shown the value of examining the dazzling diversity of life, especially in endangered species.

“We not only need to focus on organisms that are related to us and are common, but also organisms that are uncommon and endangered, for there may be behaviors and physical features that, once they are lost, we may never understand.”

Joe Caspermeyer | EurekAlert!
Further information:
http://www.asu.edu
http://mbe.oxfordjournals.org/cgi/content/full/24/9/1963
http://www.journals.uchicago.edu/AJHG/journal/issues/v75n3/41142/41142.html

Further reports about: Genetic Verrelli aye-aye endangered nocturnal opsin primate

More articles from Life Sciences:

nachricht Molecular libraries for organic light-emitting diodes
24.04.2017 | Goethe-Universität Frankfurt am Main

nachricht Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Molecular libraries for organic light-emitting diodes

24.04.2017 | Life Sciences

Research sheds new light on forces that threaten sensitive coastlines

24.04.2017 | Earth Sciences

Making lightweight construction suitable for series production

24.04.2017 | Machine Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>