6/21 was the summer solstice -- the longest day of the year as the rays of the sun are perpendicular to the Tropic of Cancer and the beginning of summer in the northern hemisphere. On this day the sun "set" at 11:45pm and was schedule to "rise" again at 4:20am the next day. I say "set" and "rise" because it never seems dark enough during this time of year to consider the sun to be fully set so that it can then fully rise. I took this picture at 11:30pm on the summer solstice:
After reading over my last post, I realized I haven't really given a description of what my field work entails so it would be silly for me to assume anyone would believe we found it necessary to take a break while doing research in Alaska. I guess I should explain myself...
I will start with a broad overview of the research associated with stickleback and end with the data I am collecting for my own project. There are quite a few stickleback labs all over the globe interested in different aspects of stickleback research, including genetics, morphology, physiology, life history traits, and behavior -- just to name a few avenues of research. Stickleback are quite useful for studying trait evolution and the relationship between the environment and trait evolution (this often includes the study of phenotypic plasticity -- the ability of organismal traits to change in response to environmental change). Marine stickleback have invaded different freshwater environments in the Pacific Northwest (e.g. BC and AK) and, in some cases, the freshwater regimes are very similar providing natural replication for experiments and comparisons. By regimes, I am referring to specific combinations of environmental factors whether they be related to biotic or abiotic conditions of the freshwater environment -- for instance -- presence or absence of predatory species, high or low calcium content, abundance of benthic prey or plankton. Such factors can shape the morphological, life history, and behavioral traits of a given population resulting in the population following a particular evolutionary trajectory. Some stickleback researchers are interested in what evolutionary trajectories result based on environmental conditions and the extent that the trajectories are dependent on the underlying genetics of the organism versus the environmental pressures experienced by the organism (or, many times, evolutionary biologists are interested in questions of untangling or coupling the genotype and environmental influence to determine evolutionary trajectories).
There are many great stickleback biologists who study morphology and life history traits (e.g. age and size at reproduction, traits related to egg/sperm production). This requires catching stickleback (often in small traps) so that population sizes can be estimated or males and females can be collected and used for different types of measurements (age, clutch size, body condition and body shape). Such data can provide information on the relationship between the environment encountered and the traits observed. For instance, the full pelvic girdle found in the marine stickleback (an important form of protection from many predatory fish) has been retained in many populations where predatory fish are present. Sometimes catching stickleback for such research is not very rewarding (for example, Lauren and Rachel at Trouble Lake pulling traps and counting the few fish they caught -- possibly less than the mosquito bites they caught while collecting):
Stickleback from lakes with different genetic backgrounds and different environmental regimes can be crossed in the laboratory to produce lab-reared offspring for morphological, life history, behavioral and genetic studies. Screening phenotypes is very useful procedure for studying genomes -- mapping genes and QTLs. Genetic studies involving stickleback have increased in number over the last several years and are of great potential value to the field of medicine (e.g. osteological disorders) -- and such studies are very interesting and complementary to field data unraveling evolutionary processes.
More on stickleback behavioral research and my particular interests in stickleback when I next get a chance to write...I think I need a break at the moment...
3 weeks ago