(Press-News.org) Two groups of small fish, one from a Caribbean island and one from the Yucatan peninsula of Mexico, exhibit some of the fastest rates of evolution known in any organism, according to a new UC Davis study.
About 50 species of pupfish are found from Massachusetts to Venezuela -- and they are all pretty much the same, said lead study author Chris Martin, a UC Davis graduate student working with Peter Wainwright, a professor of evolution and ecology at UC Davis.
"They look the same and they act the same," eating detritus and algae off rocks, Martin said.
Except in two places. In shallow, salty lakes on San Salvador island in the Bahamas, Martin found that one of the three pupfish species present lives by biting the scales off other fish, while another eats small snails and clam shrimp.
No other pupfish is known to eat scales, Martin said.
Among pupfish originally from the Yucatan area, one eats other fish and another feeds on plankton. Sadly, these fish are now extinct in the wild and only found in labs and aquaria.
The pupfish evolved changes to their jaws to match their specialized diet, allowing Martin to construct an evolutionary map for the species.
If the evolution of all pupfish is like a steadily expanding cloud, Martin found that the San Salvador Island and Yucatan pupfish are like bursts of fireworks within it. They show explosive rates of evolution – changing up to 130 times faster than other pupfish, he said.
It's not clear why the pupfish in the two locations are evolving so fast. In both places, the lake water is hot and salty – but that's true in other places where pupfish live. And mosquito fish, found in the same two lakes, show no signs of rapid change.
Martin is continuing his research by taking lab-bred fish, including hybrids, back to the lakes to see whether they thrive. He hopes to see which fish succeed out of a spectrum of hybrids.
The research is published online in the journal Evolution. Martin is a National Science Foundation graduate research fellow.
INFORMATION:
'Explosive' evolution in pupfish
2011-04-28
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
Headwater Discover the Undiscovered - Our Top 10 'Sight Swap' Ideas
2011-04-28
It is, undoubtedly, a huge privilege to live in a world crammed with the most incredible "must see" sights; however many lesser known places, hidden away in tucked away corners, often provide the most rewarding and personal experiences. Here are our Top 10 "Sight Swaps"...
1. Pisa for Bologna
Queue behind tourists from all corners of the world to have your photo taken trying to "push back up" the leaning tower of Pisa, or head instead to the mediaeval leaning towers of Bologna, one of the largest and most perfectly preserved historic centres ...
Guns in the home provide greater health risk than benefit
2011-04-28
Los Angeles, CA (APRIL 26, 2011) Despite the fact that nearly one-third of American households have a firearm, studies show that having a gun in the home poses a household a greater health risk than a potential benefit. A new study released in the American Journal of Lifestyle Medicine (published by SAGE) examined scientific research on both sides of the debate to put hard numbers to this on-going discussion.
Author David Hemenway studied the various risks of having a gun in the home, including accidents, suicide, homicide, and intimidation. Additionally, the benefits ...
Heaviest antimatter found
2011-04-28
The antimatter equivalent of helium nuclei has been produced by an international team of physicists working with the Relativistic Heavy Ion Collider at the U.S. Department of Energy's Brookhaven National Laboratory in New York. Two University of California, Davis, professors are members of the team. A paper describing their results is published online this week by the journal Nature.
"This is the heaviest antimatter anyone has ever created," said Manuel Calderon de la Barca Sanchez, professor of physics at UC Davis and an author of the paper. Authors also include Daniel ...
World's First Environmentally Sustainable Zoo To Be Built From The Ground Up
2011-04-28
You may have heard, watched or read the story...a seaside community zoo becomes the first U.S. zoo to perform a full-scale, total evacuation during a hurricane. The Alabama Gulf Coast Zoo made headlines in 2004 when Zoo Director Patti Hall relocated over 270 exotic zoo animals, a staff and their families, to her inland home to wait out Hurricane Ivan (category 4 storm). The zoo was destroyed, and while rebuilding, endured two more unprecedented evacuations ten months later during Hurricanes Dennis and Katrina.
If this story doesn't ring a bell, it will... as the Alabama ...
The doctor will see all of you now? Group doctor visits may be feasible for Parkinson's disease
2011-04-28
ST. PAUL, Minn. –Group appointments where doctors see several people for a longer time may be feasible for Parkinson's disease, according to a new study published in the April 27, 2011, online issue of Neurology®, the medical journal of the American Academy of Neurology (AAN).
Group visits have shown benefits for people with other chronic conditions, but have not been evaluated for people with Parkinson's disease. Group visits can allow patients more time with their doctor than they might have with individual appointments and more time for doctors to provide education ...
Physics World highlight: There's more to implants than meets the eye
2011-04-28
In this month's Physics World, Richard Taylor, professor of physics, psychology and art at the University of Oregon, warns that artificial retinal implants – a technology fast becoming a reality – must adapt to the unique features of the human eye in order to become an effective treatment.
The gap between digital camera technology and the human eye is getting ever smaller, in terms of both the number of light-sensitive detectors and the space that they occupy. A human retina typically contains 127 million photoreceptors spread over an area of 1100 mm2. In comparison, ...
Swiss-US team finds indigenous cases of leprosy in the Southern United States
2011-04-28
Using advanced DNA analysis and extensive field work, an international research team has confirmed the link between leprosy infection in Americans and direct contact with armadillos. In a joint collaboration between the Global Health Institute at EPFL in Switzerland and Louisiana State University, clear evidence was found that a never-before-seen strain of Mycobacterium leprae has emerged in the Southern United States and that it is transmitted through contact with armadillos carrying the disease. The results will be published on April 28th in the New England Journal of ...
Bariatric surgery better than dieting for glucose control
2011-04-28
Durham, N.C., and New York, N.Y.. – Researchers at Duke University Medical Center and St. Luke's and Roosevelt Hospital Center, Columbia University, have uncovered a new clue for why bariatric surgery is more effective than dietary remedies alone at controlling glucose levels.
This discovery, and facts gleaned from their previous studies, provide even more evidence that branched-chain amino acids are biomarkers that deserve careful scrutiny in the development and treatment of diabetes.
Physicians have observed that bariatric surgery results in improved blood sugar ...
New technique extends cancer-fighting cells' potency in melanoma patients
2011-04-28
BOSTON--Like brainy bookworms unprepared for the rough and tumble of post-graduation life, white blood cells trained by scientists to attack tumors tend to fade away quickly when injected into cancer patients. Dana-Farber Cancer Institute scientists, however, have developed a technique that can cause such cells to survive in patients' bloodstreams for well over a year, in some cases, without the need of other, highly toxic treatments, a new study shows.
In a paper published in the Apr. 27 issue of Science Translational Medicine, the researchers report the results of a ...
Agulhas leakage fueled by global warming could stabilize Atlantic overturning circulation
2011-04-28
MIAMI – April 27, 2011 – The Agulhas Current which runs along the east coast of Africa may not be as well known as its counterpart in the Atlantic, the Gulf Stream, but researchers are now taking a much closer look at this current and its "leakage" from the Indian Ocean into the Atlantic Ocean. In a study published in the journal Nature, April 27, a global team of scientists led by University of Miami (UM) Rosenstiel School of Marine & Atmospheric Science Associate Professor Lisa Beal, suggests that Agulhas Leakage could be a significant player in global climate variability. ...