Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

On a fly’s wing, scientists tally evolution’s winners and losses

20.04.2006
Evolution has always been a game of wins and losses.

Anatomical features, scientists know, come and go. The animal kingdom is full of critters that have independently gained or lost similar features. Whales and snakes, for instance, have lost their legs. Winged flight evolved separately in birds, bats and pterosaurs at different times in evolutionary history.

Now, writing today (April 20, 2006) in the journal Nature, a team of scientists from the Howard Hughes Medical Institute (HHMI) at the University of Wisconsin-Madison, reveal the discovery of the molecular mechanisms that allow animals to switch genes on or off to gain or lose anatomical characteristics.

"Evolution can and does repeat itself," says Sean B. Carroll, a UW-Madison genetics professor and senior author of the new Nature report that describes how males of different fruit fly species have independently gained -- and repeatedly lost -- the wing spots that make them appealing to females.

"These spots have appeared and disappeared independently in different species at different times over the course of evolutionary history, and have been junked at least five times in one particular group," says Benjamin Prud’homme, a UW-Madison post-doctoral fellow working in Carroll’s lab and the lead author of the new study. "We have shown that each of these transitions corresponds with changes in how a certain gene is used."

The new study reveals how evolution occurs at the finest level of detail and explains the molecular mechanisms at work when animals lose or gain features. In the fruit fly, a gene known as "yellow" is responsible for the fly’s wing decoration.

"The gene is like a paintbrush," says Carroll. "But it needs instructions as to where to paint. Little switches embedded in DNA around the gene have the instructions. It is these switches that are evolving. The fly can lose a spot because of a very small change in his spot switch."

Known as "regulatory elements," the switches that govern gene activity are DNA sequences that act like toggles to turn genes on or off. Individual genes can have several switches, Carroll notes, each one devoted to controlling the gene in a different tissue or body part.

In the case of fruit flies, the changes in the switches’ activity are driven by the preferences of females. The flies meet on flowers and the male fly -- to put the female in the mood -- waves his wings and displays his conspicuous wing spots.

"Female preference is a strong force in the evolution of anatomy," explains Prud´homme. "This phenomenon -- sexual selection -- is all over the animal kingdom. It was one of Darwin’s great ideas."

Finding the same gene and the same processes at work -- molecular switch evolution -- in two distantly related species of fly is remarkable, according to Carroll, because it shows how and why evolution repeats itself.

"The funny thing is they came up with the same solution," Carroll says. "The big picture is that we are seeing the repetition of evolution -- in animals widely divergent in time and space -- at several key levels."

Sean B. Carroll | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Life Sciences:

nachricht Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides
16.07.2018 | Tokyo Institute of Technology

nachricht The secret sulfate code that lets the bad Tau in
16.07.2018 | American Society for Biochemistry and Molecular Biology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Subaru Telescope helps pinpoint origin of ultra-high energy neutrino

16.07.2018 | Physics and Astronomy

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides

16.07.2018 | Life Sciences

New research calculates capacity of North American forests to sequester carbon

16.07.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>