Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study catches 2 bird populations as they split into seperate species

15.07.2009
A new study finds that a change in a single gene has sent two closely related bird populations on their way to becoming two distinct species. The study, published in the August issue of the American Naturalist, is one of only a few to investigate the specific genetic changes that drive two populations toward speciation.

Speciation, the process by which different populations of the same species split into separate species, is central to evolution. But it's notoriously hard to observe in action. This study, led by biologist J. Albert Uy of Syracuse University, captures two populations of monarch flycatcher birds just as they arrive at that evolutionary crossroads.

Monarch flycatchers are small, insect-eating birds common in the Solomon Islands, east of Papua New Guinea. Uy and his team looked at two flycatcher populations: one found mostly on the large island of Makira, the other on smaller surrounding islands. Besides where they live, the only discernable difference between the two populations is the color of their feathers. The birds on Makira have all black feathers. Birds on the smaller islands have the same black feathers, but with a chestnut-colored belly.

The question of whether these two populations are on the road to speciation comes down to sex. When two populations stop exchanging genes—that is, stop mating with each other—then they can be considered distinct species. Uy and his team wanted to see if these flycatchers were heading in that direction.

It would be all but impossible to try to catalog every occasion on which an all-black flycatcher mated with a chestnut-bellied. So Uy and his team used another test.

Flycatcher males defend their mating territories. If a potential rival male enters another's territory, fights often ensue. If all-black males react less violently to chestnut-bellied males and vice versa, that's an indication that the two don't recognize each other as reproductive rivals. If they don't see each other as rivals, then one can assume that mating between members of the two populations is rare.

So Uy and his team made all-black and chestnut-bellied taxidermy models. They used the models to invade mating territories in each population. As expected, when all-black birds were presented with all-black models, they attacked. But when all-black birds encountered chestnut-bellied models, they were much less likely to go on the offensive. The same scenario held for the chestnut-bellied birds.

That males from the two populations no longer view the other as a reproductive threat is a good indication that not much mating is taking place between the two groups. Their evolutionary paths are diverging, Uy and his team found—all because of a change in plumage.

The researchers then went a step further. They looked into the birds' genomes to see what genes may have played a role in the different plumage pattern. They found only one: the melanocortin-1 receptor gene (MC1R). The MC1R gene regulates the production of melanin, which gives skin and feathers their color. The all-black and chestnut-bellied birds had different versions of the MC1R gene, which gave rise to the plumage change.

That change appears to have been enough to create a reproductive barrier for flycatchers. Not every species is so picky, so a color change doesn't always drive speciation. Nonetheless, these results suggest that it can take as little as one gene, in the right spot in the genome, to cause a fork in the evolutionary road.

J. Albert C. Uy, Robert G. Moyle, Christopher E. Filardi, Zachary A. Cheviron, "Difference in Plumage Color Used in Species Recognition between Incipient Species Is Linked to a Single Amino Acid Substitution in the Melanocortin-1 Receptor." The American Naturalist August 2009.

Since its inception in 1867, the American Naturalist has maintained its position as one of the world's most renowned, peer-reviewed publications in ecology, evolution, and population and integrative biology research.

Kevin Stacey | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Studies and Analyses:

nachricht Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT

nachricht Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>