The evolution of the mammals of the Queen Charlotte Islands, British Columbia

Ermine larger than adjacent mainland and with smaller sexual dimorphism (29%) compared with coastal forms (42-47%) or inland (52-57%). Difference arose in situ, doesnt reflect size of colonising stock. Reckons all species except caribou present since onset of last glaciation, because islands ice-free islands offered refuge for mainland species, so have had 100,000 yrs to evolve distinguishing characters. Haida people probably helped disperse some animals in canoes.

Author J. B. Foster
Year 1965
Secondary title Occasional Papers of the British Columbia Provincial Museum
Volume 14
Pages 1-130