White-tailed ptarmigan The species name "leucura" was for a long time misspelt "leucurus", in the erroneous belief that the ending of "Lagopus" denotes masculine gender. However, as the Ancient Greek term "λαγωπους" is of feminine gender, and the species name has to agree with that, the feminine "leucura" is correct. The species name "leucura" is derived from the Latinized version of the Greek "leukos", meaning "white" and "oura", meaning "tail", in reference to the bird's permanently white tail. The white-tailed ptarmigan is the smallest of the ptarmigans and the smallest bird in the grouse family. It is a stocky bird with rounded
Arctic fox pads are covered in fur. There are two genetically distinct coat color morphs: white and blue. In the winter the white morph is white in color and turns brown along the back with light grey around the abdomen in summer. The blue morph is often a dark blue, brown, or grey color year-round. Although the blue allele is dominant over the white allele, 99% of the Arctic fox population is the white morph. The fur of the Arctic fox provides the best insulation of any mammal. The fox has a low surface area to volume ratio, as evidenced by its