Moose evolved in Asia and crossed the Bering Land Bridge into North America, after the last ice age. So, all moose on this continent are related genetically (unlike those in Russia and elsewhere, who have shown chromosomal distinctions). This is one factor that has led contemporary scientists to believe that the size differences may not be based on genetics, but more on habitat. The theory is that with higher quality forage, you get better habitat, which equals bigger, more productive moose. Here in the Montana Rockies, moose are not only smaller, but they are less productive. Cows only produce twins 5-10 percent of the time, as compared to the 20-70 percent (!) rate that Alaskan moose have demonstrated. Learn more by listening to the podcast…

This Field Note was written by Danielle Lattuga. Would you be interested in writing one? Contact Allison De Jong, Field Notes editor, at adejong [at] montananaturalist [dot] org or 406.327.0405. Please visit the Field Notes website at the Montana Natural History Center for more information.