Hypothesis: Fluctuating asymmetry (FA) – random deviations from perfect symmetry that are used as a measure of developmental stability – is an effective indicator of stress and fitness in threespine stickleback. Organisms: The threespine stickleback (Gasterosteus aculeatus) and two other species, the brook stickleback (Culaea inconstans) and ninespine stickleback (Pungitius pungitius), were the focus of a review of the literature. In addition, four populations of G. aculeatus – one anadromous population from the Kamchatka River, two marine populations from the White Sea, and one freshwater population from the White Sea basin – were studied in the field. Methods: A review of the literature relating fluctuating asymmetry to different variables, and a comparison of fluctuating asymmetry in four populations of stickleback, which differed in geographical distribution and life history, using lateral plates and four cranial bones (operculum, lachrymal, third suborbital, quadrate). Results: An appraisal of the literature on fluctuating asymmetry suggests that decreasing interest in FA studies has likely resulted from conflicting research results. To some extent, this problem is likely caused by the morphological structures used in FA analysis, which are generally limited to the lateral plates and pelvic fins. These structures can evolve quickly in response to various environmental changes, thus their fluctuating asymmetry reflects not only individual fitness and stress, but also multiple uncontrolled factors that may directly affect those same structures. Using four cranial bones in our analysis showed lower fluctuating asymmetry in anadromous stickleback from the Kamchatka Peninsula compared with marine and freshwater stickleback from the White Sea and its basin. This may be caused by more favourable feeding conditions in the North Pacific than in the White Sea. The different environmental conditions at these locations did not appear to have a significant effect on fluctuating asymmetry, although the comparison of freshwater, anadromous, and marine populations showed that the fluctuating asymmetry of the structures we used is responsive to these differences. Our FA analysis of the selected bone structures reveals clear heterogeneity in stickleback with different life histories. We suggest that these structures can be considered reliable for studies of fluctuating asymmetry in stickleback fishes.
|Журнал||Evolutionary Ecology Research|
|Состояние||Опубликовано - 1 янв 2019|
Предметные области Scopus
- Экология, эволюция поведение и систематика