Bergman's Rule is a basic biological principle that says a species in northern climates will be larger than it's counterpart in southern climates. Thus large whitetail in Canada vs Texas etc. The same can be said for coyotes. Also, animals in warmer climates will have proportionally larger appendages (ears, legs etc) to dissipate heat better versas shorter appendages for northern species, which helps them conserve energy. These are what we call "traits" and not necessarily sub-species. I'm not a splitter but a lumper and therefore a coyote is a coyote. Be it Canada or Florida, they just exibit different traits.