For the Nov 4 challenge "It's Evolving!" :

"This week, we challenge you to depict the evolved form of a real-world species (as if it's in a video game)."

Well, the species is Didelphis viginiana, commonly known as the Virginia opossum, or the "Two-Wombed Virginian" if we're translating the Latin literally. Its evolved form is largely than a grizzly, so it's ill-suited for life in the trees. Its dens can be found in caves, primarily in the tundras of the subartic.