Iceland's arctic foxes are the most populous and also the most persecuted within the nordic countries. The government pays a bounty per foxtail in hopes of protecting eider duck farms and livestock from predation. The tradition of fox hunts has provided biologists with the perfect opportunity to research and record the lives of Iceland's largest land mammal. For several decades, hunters have been donating their dead foxes to research, receiving no compensation outside of the life history reports of each kill. The data accrued from this collaboration can inform our understanding of foxes and their connection with the land and sea.
Dr. Ester Rut Unsteinsdóttir is a biologist who studies and dissects the bodies received from hunters. She works at the Icelandic Institute of Natural History and is the country's leading expert on foxes, continuing the work of her late mentor Páll Hersteinsson. She receives and dissects hundreds of foxes per year, contributing to a growing body of knowledge and one of the most extensive datasets on the species. Ester founded the Arctic Fox Center in Súðavík with Páll in 2010, as a museum and exhibition space that helps educate people about the research and history of the foxes. Her long-standing involvement in fox biology and her relationship with the hunters gives her the most well-rounded perspective of the species' place in culture and environment.
Geometric morphometrics is the quantitative analysis of shape, whereby the multidimensional geometric information of an object is translated into Cartesian coordinates (Klingenberg and Monteiro, 2005). Discernable, repeatable points on bone act as landmarks that can then be compared both within and between specimens. Fluctuating asymmetry concerns the 'directionally random' deviations from pairwise symmetry between bodily elements of an organism (Leung and Forbes, 1997). While pairwise elements, like two hands, or two wings, or two halves of a mandible, within a single body should be mirror images of each other, slight deviations from this ideal state can be measured using geometric morphometrics. While no one organism is perfectly symmetrical because of the inherent messiness of becoming a breathing, moving, eating entity from a ball of cells, the idiosyncratic changes from one pairwise element to another can be indicative of developmental stressors within a single individual. If an entire population of individuals is randomly asymmetrical (without a directional bias for either left or right asymmetry), it can be an indicator of some larger problem that is powerful enough to cause a population-wide disruption in development (Klingenberg, 2015).
Question: Is there a difference in the fluctuating asymmetry between two populations of Icelandic arctic foxes due to difference developmental pressures, namely biopollutants?
Hypothesis: The costal arctic fox will have higher FA than coeval inland arctic foxes as a consequence of being an apex predator of the mercury cycle.
Methods: Photograph left and right mandibles of X arctic foxes belonging to both the coastal and inland populations in high resolution to collect 2D shape data. The photographs will be digitized using TPSdig software using XX landmarks. The landmark definitions are included as an appendix of this report, and are defined in alignment with accepted scientific literature.
The digitized shape coordinates will be subsequently analyzed using MophoJ software (Klingenberg, 2011).
Klingenberg, C. P., & Monteiro, L. R. (2005). Distances and directions in multidimensional shape spaces: implications for morphometric applications. Systematic Biology, 54(4), 678-688.
Klingenberg, C. P (2011). MorphoJ: an integrated software package for geometric morphometrics. Molecular ecology resources, 11(2), 353-357.
Klingenberg, C. P. (2015). Analyzing fluctuating asymmetry with geometric morphometrics: concepts, methods, and applications. Symmetry, 7(2), 843-934.
Leung, B., & Forbes, M. R. (1997). Modelling fluctuating asymmetry in relation to stress and fitness. Oikos, 397-405.