Greater short-horned lizard its close relative the pygmy short-horned lizard ("Phrynosoma douglasii" ), which has the same basic body type consisting of small pointed scales around the head and back. Until recent mitochondrial DNA evidence, "P. hernandesi" was considered to be the same species as "P. douglasii". They are now considered distinct species with the pygmy short-horned lizard ("P. douglasii" ) occupying the northwest portion of the United States and extreme southern British Columbia. When placed together the two are easily distinguished at full size, the pygmy short-horned lizard being much smaller. "P. hernandesi" is a highly variable species with different geographic populations
Great horned owl of microhabitat proved that open areas provided more hunting success on five species of rodent, with cloudy nights and denser bush foliage both decreasing success. Prey can vary greatly based on opportunity. According to one author, "Almost any living creature that walks, crawls, flies, or swims, except the large mammals, is the great horned owl's legitimate prey". In fact, the great horned owl has the most diverse prey profile of any raptor in the Americas. Over 500 species have been identified as great horned owl prey, with dozens more identified only to genus or general type (especially numerous invertebrates) and