Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Butterfly 'eyespots' add detail to the story of evolution

28.05.2014

A new study of the colorful "eyespots" on the wings of some butterfly species is helping to address fundamental questions about evolution that are conceptually similar to the quandary Aristotle wrestled with about 330 B.C. – "which came first, the chicken or the egg?"

After consideration, Aristotle decided that both the egg and the chicken had always existed. That was not the right answer. The new Oregon State University research is providing a little more detail.


The eyespots on this squinting bush brown butterfly are helping researchers answer questions about fundamental evolution.

Credit: Photo by William Piel


When wings are closed, these eyespots serve as camouflage for a painted lady butterfly.

Credit: Photo by Jeffrey Oliver

The study, published today in Proceedings of the Royal Society B, actually attempts to explain the existence of what scientists call "serial homologues," or patterns in nature that are repetitive, serve a function and are so important they are often retained through millions of years and across vast numbers of species.

Repeated vertebra that form a spinal column, rows of teeth, and groups of eyespots on butterfly wings are all examples of serial homologues. Researchers have tracked the similarities and changes of these serial features through much time and many species, but it's remained a question about how they originally evolved.

... more about:
»attack »butterfly »chicken »eggs »function »individual »species »spinal

Put another way, it's easier to see how one breed of chicken evolved into a different breed of chicken, rather than where chickens – or their eggs - came from to begin with.

Butterfly wings are helping to answer that question. These eyespots, common to the butterfly family Nymphalidae, now serve many butterflies in dual roles of both predator avoidance and mate identification. One theory of their origin is that they evolved from simpler, single spots; another theory is that they evolved from a "band" of color which later separated into spots.

"What we basically conclude is that neither of the existing theories about butterfly eyespots is correct," said Jeffrey Oliver, a postdoctoral scholar in the Department of Integrative Biology of the OSU College of Science. "The evidence suggests that a few eyespots evolved as a group at about the same time, but behaved somewhat as individual entities."

Having appeared as a result of some genetic mutation, however, the eyespots then had the capability to move, acquire a function that had evolutionary value, and because of that value were retained by future generations of butterflies. And at all times, they retained the biological capacity for positional awareness – the eyespots formed in the same place until a new mutation came along.

"At first, it appears the eyespots helped this group of butterflies with one of the most basic aspects of survival value, which is avoiding predators," Oliver said.

On the side of the wing that predators saw when the wings were closed, the eyespots could have served as camouflage from a distance, and up close almost a "bulls-eye" for a predator to see and attack. But this directed the attack toward the tips of less-important wings, and not the more vulnerable head or body of the insect.

But just as important, Oliver said, the study indicates how through continued mutation these eyespots moved to a completely different place – the other side of the wing. There, they performed a completely different function – helping the butterfly to attract and be identified by optimal mates.

"If you take this same concept and apply it to other important features like vertebra and a spinal column, it suggests that some small number of bones would form through mutation, and eventually move, join and be perpetuated as they acquired a function with survival value," Oliver said.

"There would be a biological position in which they were supposed to form, and that would be retained," he said. "And over time, the vertebra might expand in number, and acquire other functions that had nothing to do with their original function, but which still had value."

The evolution of life has never been simple, as Aristotle and the other early philosophers found out. But one bone or butterfly eyespot at a time, the pieces continue to come together.

###

Editor's Note: Digital images of butterflies are available to illustrate this story.

Squinting bush brown, showing "eyespots": http://bit.ly/1jYtyKz

Painted lady: http://bit.ly/1hvwqJp

Jeffrey Oliver | Eurek Alert!

Further reports about: attack butterfly chicken eggs function individual species spinal

More articles from Life Sciences:

nachricht Tracking the American Woodcock
28.07.2015 | University of Arkansas, Fayetteville

nachricht Possible Path Toward First Anti-MERS Drugs
28.07.2015 | American Crystallographic Association (ACA)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Superfast fluorescence sets new speed record

Plasmonic device has speed and efficiency to serve optical computers

Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.

Im Focus: Unlocking the rice immune system

Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight

A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...

Im Focus: Smarter window materials can control light and energy

Researchers in the Cockrell School of Engineering at The University of Texas at Austin are one step closer to delivering smart windows with a new level of energy efficiency, engineering materials that allow windows to reveal light without transferring heat and, conversely, to block light while allowing heat transmission, as described in two new research papers.

By allowing indoor occupants to more precisely control the energy and sunlight passing through a window, the new materials could significantly reduce costs for...

Im Focus: Simulations lead to design of near-frictionless material

Argonne scientists used Mira to identify and improve a new mechanism for eliminating friction, which fed into the development of a hybrid material that exhibited superlubricity at the macroscale for the first time. Argonne Leadership Computing Facility (ALCF) researchers helped enable the groundbreaking simulations by overcoming a performance bottleneck that doubled the speed of the team's code.

While reviewing the simulation results of a promising new lubricant material, Argonne researcher Sanket Deshmukh stumbled upon a phenomenon that had never been...

Im Focus: NASA satellite camera provides 'EPIC' view of Earth

A NASA camera on the Deep Space Climate Observatory (DSCOVR) satellite has returned its first view of the entire sunlit side of Earth from one million miles away.

The color images of Earth from NASA's Earth Polychromatic Imaging Camera (EPIC) are generated by combining three separate images to create a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Euro Bio-inspired - International Conference and Exhibition on Bio-inspired Materials

23.07.2015 | Event News

Clash of Realities – International Conference on the Art, Technology and Theory of Digital Games

10.07.2015 | Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

 
Latest News

Possible Path Toward First Anti-MERS Drugs

28.07.2015 | Life Sciences

Smart Hydrogel Coating Creates “Stick-slip” Control of Capillary Action

28.07.2015 | Materials Sciences

Are Fish Getting High on Cocaine?

28.07.2015 | Ecology, The Environment and Conservation

VideoLinks
B2B-VideoLinks
More VideoLinks >>>