6.1 Discussion

Each island seems to have a different phenotype that is advantageous depending on the island. A,B, and C are mostly selected for on islands, as their reduced and lack of stripes are adapted to their environments. However, the mainland dominates with snakes which have phenotype D, as their stripes would be most beneficial to have in their leafy forest environment. Any snake that migrates from the mainland would stick out to predators since they do not have the camouflage that the other snakes have: reduced or lack of stripes. Similarly, snakes that migrate from the islands to the mainland would not have the stripes to camouflage them in the leafy environment. This has the consequence of making migration from island to mainland (and vice versa) very difficult. However, the graphs show that phenotype D, the striped snakes, were able to survive on the islands. They are present in a much smaller number than the other phenotypes, but they still have the ability to survive there. In the Ontario graph, there are exclusively snakes with phenotype D, which means that there is strong selection for striped snakes in this environment. I think one large part of migration has to do with location, and this is why there are more snakes with phenotype D on Kelley's island due to it being closer to the peninsular mainland.