Masters Thesis
The applications of rank analyses for answering ecological and evolutionary questions in natural systems
Co-supervisers: Dr. Andrew Hendry and Dr. Gregor Fussman
Department of Biology, McGill University (2018-2021)
Co-supervisers: Dr. Andrew Hendry and Dr. Gregor Fussman
Department of Biology, McGill University (2018-2021)
We leveraged a well-studied system to explore the benefits of using an ordinal rank metric (ie. relative length in rank, 2nd longest fish) in comparison to a quantitative metric (ie. length in centimetres). We explored this contrast in a variety of contexts exploring several biological questions related to ecological and evolutionary processes in natural systems these included: probability of recapture, partitioning variance between biological levels (ie. pool, river, or drainage level), and comparing individuals through time to examine consistency. We found that when partitioning variance between levels the interpretaiton of results was comparable between ordinal or quantitative metrics, in survival quantitative metrics provided better predictive power, and in examining consistency rank provided clearer interpretation in the context of a mark-recapture design comparing individuals to themselves through time. Overall rank metrics are a powerful tool and further applications should be considered in quantitative biology outside of classical uses in dominance and other hierarchies.
Blue Carbon Stocks in Recreational Land
FOME Lab, Dalhousie University. Owl's Head Provincial Park, Nova Scotia, Canada.
Working with the FOME lab at Dalhousie University I am measuring and quantifying the Carbon stocks in the coastal area near a proposed development on recreational land. The purpose of this project is to determine the economic value of native Nova Scotian coastal systems in the context of their capacity to sequester carbon annually. Additionally, we want to provide information on the environmental and economic consequences of disturbing previously sequestered carbon in the form of carbon stocks in the eelgrass, tidal marsh, and terrestrial wetlands systems through the commercial development of the land.
(non)parallel evolution in Trinidadian Guppies
Alexis Heckley, Allegra Pearce, Andrew Hendry, Kiyoko Gotanda, and Krista Oke
![Picture](/uploads/1/2/2/4/122474410/published/guppy-map.jpeg?1683917499)
Conducted a systematic review of literature within the Trinidadian guppy system over 40 years. We sought to determine how strong parallel evolution is in the classic high and low predation dichotomy seen in guppy literature and then to determine ecological factors that impact this. We explored the trait type, time since introduction for experimentally introduced populations, and the ecological complexity of populations being compared. In this case we looked at traits including populations from multiple groups or from within one group for three classifications: between the north and south slope, between the Caroni and Oropouche drainages, between natural and introduced populations.
Parasites vs. the bold and the beautiful
I have worked on several projects investigating the relationship between colour and parasitism and colour and boldness. These projects use the R package patternize (https://github.com/StevenVB12/patternize) to complete spatial colour pattern analyses (ie. PCA on colour expression in size and area) and quantitative (ie. relative area of orange) colour metrics and compare them to ecological observations such as parasite load and behaviour to determine the impact parasitism has on these.
Honours Thesis
The role of lipids in facilitating cardiac function during anoxia in Pacific (Eptatretus stoutii) and Atlantic hagfish (Myxine glutinosa)
Superviser: Dr. Todd Gillis
Integrative Biology Department, University of Guelph (2017-2018)
Superviser: Dr. Todd Gillis
Integrative Biology Department, University of Guelph (2017-2018)
![Picture](/uploads/1/2/2/4/122474410/screen-shot-2018-10-11-at-8-12-09-pm_orig.png)
Pacific hagfish have long been know to have extreme hypoxia tolerances, thought to have evolved as an adaptation to behaviours such as feeding within moribund whale carcasses (a low oxygen environment) and burrowing in sand to remain undetected. Though famous for their ability to produce slime, they have the ability to survive and recover after several hours of anoxia (36 hours in Pacific hagfish, Atlantic hagfish only observed up to several hours prior to this). We exposed hagfish to physiologically relevant anoxia exposures (Pacific - 30 hr; Atlantic - 16 hr) and analyzed blood and tissue chemistry to determine if a novel lipid metabolism pathway may explain this extreme tolerance.