Sticklebacks are a small silver-colored fish, barely two inches in length; they are found throughout the Northern Hemisphere in both oceans and freshwater.
"Populations of freshwater stickleback arise when new habitats open up and are colonized," Cresko said. "Alaska has a lot of lakes that have been around only about 10,000 years, formed after glaciers receded. Instead of dying out when they were cut off from saltwater, they evolved very rapidly and in a lot of ways, such as in their bones and armor, the shapes of their jaws, as well as coloration and behavior. When one population no longer recognizes and won't mate with another population, they effectively become a new species, so some of the regions we are identifying may be important for speciation, too."
Sticklebacks have long been a focus for behavioral biologists because of their complex courtship rituals. Only recently have they come under genetic and genomic scrutiny, and the UO has been at the forefront of such studies. Until recently, efforts focused on small numbers of traits, tracking just a few genes at a time. In a 2006 talk on campus, Cresko outlined the challenges of the research, saying that faster, cheaper DNA-analyzing tools were needed to scan entire genomes. In the audience was Eric Johnson of the UO's Institute of Molecular Biology.
For the next three years, Cresko and Johnson worked to develop a technique they called Restriction-site Associated DNA -- the development of which helped spawned Floragenex, a UO technology spinoff company -- and subsequently combined it with a genomic revolution called Next Generation Sequencing using a genome-analyzer tool known as Illumina's GA2 sequencer.
"We combined two technologies to develop sequence RAD (restricted-site associated DNA) tags," Cresko said. "With this, we can quickly look acr
|Contact: Jim Barlow|
University of Oregon