Map showing locations of cruises that have used the kits by June 2002
How can genetics be used to study fish populations? Rus Hoelzel and Halvor Knutsen have developed a project that uses genetic markers to identify population structure, levels of diversity within local populations and aspects of demographic history.
Using portable kits to generate a large pool of samples
They have been sending 'kits' to participants on research cruises to help build up our sample base. Already they have many samples from a broad geographic range for a number of different fish species, including orange roughy, roundnose grenadier and some others. DNA is being extracted from the samples and archived.
The rationale behind the project is that a number of deep-water species have fairly specific habitat requirements, and potentially low dispersal capacity. This can lead to unique population structures and small, local, effective population sizes. Some species are also very long-lived, which means that any diversity that is lost would be recovered very slowly.
What will the results show?
A major part of their study will be looking at population structure and diversity in light of historical and potential future climate change. They can assess past impact by using genetic markers to look for evidence of population displacements, expansions, contractions, etc. This information will also help them to make informed predictions about potential future impacts.
Another important aspect will be the comparative analysis between different species, across a range of different life history strategies. This will help us determine which aspects of life history are most important in generating a given population genetic structure, within the deep-sea environment.