Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Small Evolutionary Shifts Make Big Impacts – Like Developing Night Vision

22.05.2009
Minor differences in the timing of cell proliferation can explain the large differences found in the eyes of two species – owl monkeys and capuchin monkeys – that evolved from a common ancestor.

In the developing fetus, cell growth follows a very specific schedule. In the eye’s retina, for example, cones – which help distinguish color during the day – develop before the more light-sensitive rods – which are needed for night vision.

But minor differences in the timing of cell proliferation can explain the large differences found in the eyes of two species – owl monkeys and capuchin monkeys – that evolved from a common ancestor.

Researchers from Cornell, St. Jude’s Children’s Research Hospital in Tennessee and the Federal University of Para, Brazil, have found an evolutionary mechanism that provides insight into how important changes in brain structure of primates can evolve.

That evolution appears to proceed via simple genetic changes that affect the timing of development of brain regions, they report in a paper published May 18 online and in a future print issue of Proceedings of the National Academy of Sciences.

In both monkey species, the specialized eye cells develop in the growing embryo from a single retinal progenitor cell. In their basic design, the eyes of these primates have the capability and necessary architecture to be either nocturnal or diurnal, based on a species’ ecological niche and needs, said Barbara Finlay, Cornell neurobiologist and psychologist, and senior author on the paper.

Finlay and her colleagues compared the developing eyes in fetuses of the two species to better understand how the nocturnal owl monkeys developed retinas with many more rod cells than cones, while capuchin monkeys, which are active during the day (diurnal), developed more cone cells than rods.

“These two species evolved about 15 million years ago from a common ancestor that had a diurnal eye,” said Finlay. “So we believed that comparing how their eyes develop during embryonic growth could help us understand what evolutionary changes would be required to evolve from a diurnal to a nocturnal eye.”

By comparing the timing of retinal cell proliferation in the two species, the researchers found evidence that an extended period of progenitor cell proliferation in the owl monkey gave rise to an increased number of rod and other associated cells that make its eyes adept at night vision; the eyes also evolved to be large, with bigger light-gathering and light-sensing structures needed for nocturnal sight.

“The beauty of the evolutionary mechanism we have identified is that it enables the eye to almost toggle back and forth between a nocturnal and a diurnal structure,” said neurobiologist Michael Dyer of St. Jude’s hospital. “It is an elegant system that gives the eye a lot of flexibility in terms of specialization.”

This research was funded by the National Science Foundation and Brazil’s NSF equivalent, National Counsel of Technological and Scientific Development.

Blaine Friedlander | Newswise Science News
Further information:
http://www.cornell.edu

More articles from Life Sciences:

nachricht Complementing conventional antibiotics
24.05.2018 | Goethe-Universität Frankfurt am Main

nachricht Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

Surgery involving ultrasound energy found to treat high blood pressure

24.05.2018 | Medical Engineering

First chip-scale broadband optical system that can sense molecules in the mid-IR

24.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>