Navigation Links
'Time-sharing' tropical birds key to evolutionary mystery
Date:11/13/2007

KINGSTON, ON Whereas most birds are sole proprietors of their nests, some tropical species time share together a discovery that helps clear up a 150-year-old evolutionary mystery, says Queens University Biology professor Vicki Friesen.

The Queens-led international study confirms one of Charles Darwins more controversial theories first put forward in 1859 and since disputed by many experts that different species can arise, unhindered, in the same place. Others believe that a geographic barrier such as a mountain or a river is required to produce two separate species. Although focused on how species change over time through natural selection, Darwins landmark book, The Origin of Species, also speculates that it is possible for different species to develop in the same place.

The teams findings will appear this week in the on-line Early Edition of the international journal, Proceedings of the National Academies of Science (PNAS).

With PhD student Andrea Smith and an international team of researchers, Dr. Friesen studied a small seabird called the band-rumped storm petrel, which nests on desert islands in the tropics and sub-tropics. They observed that one set of petrels will breed in burrows, raise their chicks, and leave for the winter. Then a different set of birds moves in similar to a vacation time share and repeats the pattern in the very same burrows. When the season changes again, the first set of birds will return.

Were taught today that new species generally emerge as a result of a geographic barrier such as a mountain range or river, creating two separate populations that cant easily move from one place to the other, says Dr. Friesen, an expert in evolutionary biology. While that model fits for many parts of the natural world, it doesnt explain why some species appear to have evolved separately, within the same location, where there are no geographic barriers to gene flow.

The evidence for this happening in certain types of plants, insects and fish has led to a number of scientific explanations, such as salmon spawning in the same location at different times of year. Until now, however, there have only been two documented cases that such a pattern might occur in birds, and no clear evidence as to how it happens in any warm-blooded creature.

Using DNA samples retrieved from birds breeding in the Azores, Madeira, Cape Verde and the Galapagos, the researchers determined that petrels breeding in different seasons but from the same burrows did indeed differ genetically. They also learned that the seasonal species had not bred with each other for periods ranging from around 1,000 to 180,000 years, providing a series of time shots of divergence, Dr. Friesen explains.

This is important for us to know, not just as an explanation for how new species can arise, but also because biodiversity is part of a healthy ecosystem and each bird species is part of our natural heritage, she says, noting that the European Union is now elevating the conservation status of band-rumped storm petrels.

Its also exciting to be able to verify Darwins original theory! Dr. Friesen adds.


'/>"/>

Contact: Nancy Dorrance
nancy.dorrance@queensu.ca
613-533-2869
Queen's University
Source:Eurekalert

Related biology news :

1. Tropical insects go the distance to inform rainforest conservation
2. New study warns limited carbon market puts 20 percent of tropical forest at risk
3. Tropical crab invades Georgia oyster reefs -- but the long-term impact cant be predicted
4. Spatial patterns in tropical forests can help to understand their high biodiversity
5. Researchers discover forests of endangered tropical kelp
6. If corn is biofuels king, tropical maize may be emperor
7. Why do so many species live in tropical forests and coral reefs?
8. Savanna habitat drives birds, and perhaps others, to cooperative breeding
9. Uncertainty drives the evolution of cooperative breeding in birds
10. A dog in the hand scares birds in the bush
11. City birds better than rural species in coping with human disruption
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/23/2017)... 2017  Hunova, the first robotic gym for the rehabilitation and functional ... in Genoa, Italy . The first 30 robots will ... USA . The technology was developed and patented at ... IIT spin-off Movendo Technology thanks to a 10 million euro investment from ... click: ...
(Date:5/16/2017)... 16, 2017  Veratad Technologies, LLC ( www.veratad.com ), ... and identity verification solutions, announced today they will participate ... May 15 thru May 17, 2017, in ... Trade Center. Identity impacts the lives ... today,s quickly evolving digital world, defining identity is critical ...
(Date:5/16/2017)...   Bridge Patient Portal , an enterprise ... EMR Systems , an electronic medical record solutions ... established a partnership to build an interface between ... Centricity™ products, including Centricity Practice Solution (CPS), Centricity ... new integrations will allow healthcare delivery networks using ...
Breaking Biology News(10 mins):
(Date:5/26/2017)... ... May 25, 2017 , ... Activate Healthcare, a leading ... of America’s fastest growing private companies, has selected Twine for its Employee Health ... through its transformative model that empowers deep collaboration and behavior change. In randomized ...
(Date:5/26/2017)... Yorba Linda, Ca (PRWEB) , ... May 25, ... ... a number of Terumo BCT case studies, describing how process development ... learn from new results of T-cell expansion using a hollow-fiber bioreactor system, along ...
(Date:5/26/2017)... ... May 25, 2017 , ... Studying biological events ... occurrence. Live cell imaging using fluorescence microscopy is the perfect approach to explore ... microscopy methods will be discussed, from small animal models and tissues to individual ...
(Date:5/26/2017)... ... May 25, 2017 , ... LabRoots , the ... and scientists from around the world, is announcing a new textbook scholarship, the second ... undergraduate and graduate students, 17 years or older, pursuing a degree in one of ...
Breaking Biology Technology: