The Peregrine Falcon (Falco peregrinus) is the fastest animal on Earth, reaching speeds of almost 200 mph when diving for prey. Peregrines are primarily cliff dwellers, but will nest in hollow trees as well. Birds that have been introduced into the wild have found suitable homes in big cities like Chicago and St. Louis where tall buildings have substituted for cliffs. This individual was photographed at the Woodland Park Zoo in Seattle, Washington.