I have done some units on the mythology of different cultures, and what has always struck me is how much impact geography has on the origin stories. Similarly, the flora and fauna of a particular place usually show up in the stories. Japanese origin stories, for example, feature the ocean quite prominently,as well as its denizens, while you can practically feel the chill and the wind blowing through Norse tales. Native American stories show geographical features, as well as plants and animals routinely. Not knowing which specific stories you are expected to analyze, my guess is that if you learn a little about the geography and the region, you would be able to make a good beginning with analyzing stories of origin.