Stickleback Finishing

Naturally occurring species of sticklebacks have undergone a remarkable evolutionary radiation in lakes and streams around the world. Wide spread melting of glaciers at the end of the last Ice Age created thousands of new lake and streams in coastal areas of North America, Europe and Asia. These new environments were colonized by populations of ancestral marine sticklebacks. Over the last 10,000 years, the newly isolated populations of fish have adapted to a wide range of environmental conditions in different lakes and streams, generating dramatic changes in size, color, teeth, jaws, body armor, skeletal structures, and physiological traits.

Funded by the NIH Centers of Excellence in Genomic Science (CEGS) initiative, the Stanford Genome Evolution Center is developing genetic and physical mapping resources for sticklebacks which will make it possible to identify the actual genes and mutations responsible for evolutionary change. These experiments should help determine how many DNA sequence changes are required to evolve new traits, what types of genes are involved, and whether the key alterations occur primarily in the coding or regulatory regions of genes. In addition, by comparing the genetic changes responsible for evolving similar traits in widely separated populations, it should be possible to determine whether there are many different ways to evolve a new characteristic, or whether the same genes and mechanisms are used over and over again in different lakes and streams around the world.

We are generating finished sequence for the three-spine stickleback (Gasterosteus aculeatus) known to contain duplicate genes in the zebrafish (Danio rerio) as well as clones containing candidate genes thought to be responsible for evolutionary change. These data should provide insight into the mechanisms that diversify gene function in vertebrates.