Navigation Links
A snapshot of pupfish evolution in action
Date:1/10/2013

Chris Martin has bred more than 3,000 hybrid fish in his time as a graduate student in evolution and ecology at UC Davis, a pursuit that has helped him create one of the most comprehensive snapshots of natural selection in the wild and demonstrated a key prediction in evolutionary biology.

"We can see a surprisingly complex snapshot of natural selection driving the evolution of new specialized species," said Martin, who with Professor Peter Wainwright published a paper on the topic in the Jan. 11, 2013, issue of the journal Science.

The "adaptive landscape" is very important for evolutionary biology, but rarely measured, Martin said. He's been fascinated with the concept since high school.

An adaptive landscape takes variable traits in an animal or plant, such as jaw size and shape, spreads them over a surface, and reveals peaks of success (what evolutionary scientists call fitness) where those traits become most effective, or adaptive.

It is a common and powerful idea that influences thinking about evolution. But while the concept is straightforward, it is much harder to map out such a landscape in the wild.

For example, about 50 species of pupfish are found across the Americas. The tiny fish, about an inch or so long, mostly eat algae on rocks and other detritus. Martin has been studying species found only in a few lakes on the island of San Salvador in the Bahamas, where some of the fish have evolved different-shaped jaws that allow them to feed on hard-shelled prey like snails or, in one case, to snatch scales off other fish.

In a paper published in 2011, Martin showed that these San Salvadoran fish are evolving at an explosively faster rate than other pupfish.

Martin brought some of the fish back to the lab at UC Davis and bred hybrids with fish with different types of jaws. He created about 3,000 hybrids in all, which were measured, photographed and tagged. Martin then took about 2,000 of the fish back to San Salvador.

"It was the craziest thing I've done," Martin said. "I was leaning on the stack of them in the middle of Miami airport."

Martin released the young fish into enclosures in the lakes of their grandparents. Three months later, he returned to check on the survivors and plotted them out on the adaptive landscape.

Most of the surviving fish were on an isolated peak adapted to a general style of feeding, with another peak representing fish adapted for eating hard-shelled prey. Competition between the fish had eliminated the fish whose jaws put them in the valleys between those peaks. The scale-eating fish did not survive.

The results explain why most pupfish species in America have pretty much the same diets, Martin said. The generalists are essentially stranded on their peak -- variants that get too far out fall into the valley and die out before they can make it to another peak.

"It's stabilizing selection," he said. An early burst of variation when fish entered a new environment with little competition could have allowed the shell-eaters and scale-eaters to evolve on San Salvador.


'/>"/>

Contact: Andy Fell
ahfell@ucdavis.edu
530-752-4533
University of California - Davis
Source:Eurekalert  

Related biology news :

1. Leading evolutionary scientist to discuss how genome of bacteria has evolved
2. An evolutionary surprise
3. Ancient Egyptian cotton unveils secrets of domesticated crop evolution
4. Did climate change shape human evolution?
5. A University of Tennessee professors hypothesis may be game changer for evolutionary theory
6. Analysis of stickleback genome sequence catches evolution in action
7. Study shows unified process of evolution in bacteria and sexual eukaryotes
8. Rapid method of assembling new gene-editing tool could revolutionize genetic research
9. Whats in a surname? New study explores what the evolution of names reveals about China
10. Scientists trace evolutionary history of what mammals eat
11. Not by DNA alone: How the epigenetics revolution is fostering new medicines
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
A snapshot of pupfish evolution in action
(Date:3/2/2017)... YORK , March 2, 2017 Summary ... better understand Perrigo and its partnering interests and activities since ... ... Partnering Deals and Alliance since 2010 report provides an in-depth ... leading life sciences companies. On demand company reports ...
(Date:2/28/2017)... , Feb. 28, 2017   Acuant , ... software globally, announces significant enhancements to new and core ... 2016. New products include mobile and desktop Acuant FRM ... TM - a real time manual review of ... idScan® technology provides the fastest and most accurate capture ...
(Date:2/24/2017)... -- EyeLock LLC, a leader of iris-based identity authentication ... solution on the latest Qualcomm® Snapdragon™ 835 mobile ... Congress 2017 (February 27 – March 2, ... Stand 3E10. The Snapdragon 835 ... combination of hardware, software and biometrics technologies ...
Breaking Biology News(10 mins):
(Date:3/23/2017)... ALBANY, New York , March 23, 2017 ... animal blood plasma products and derivatives market is fragmented due to the ... large players, such as Proliant, Thermo Fisher , and Sigma-Aldrich, ... clear leader, these three companies, collectively, held more than 76% of ... ...
(Date:3/22/2017)... ... 2017 , ... Researchers face a fundamental challenge as they ... tissues, bones, even whole organs to implant in people to treat disease or ... the developing tissue. , Current bioengineering techniques, including 3-D printing, can’t fabricate ...
(Date:3/22/2017)... , March 22, 2017   iSpecimen ®, ... that Doctors Pathology Service (DPS), a full-service ... the United States , has joined ... Health Information Network (DHIN) to make human biospecimens ... The novel program, announced in 2015 as a ...
(Date:3/22/2017)... Pa. , March 22, 2017 /PRNewswire/ ... global independent provider of product and service ... today that it has acquired EPL Archives, ... supports customers across the entire regulated product ... archive sample, document storage and ancillary services. ...
Breaking Biology Technology: