Horse breed been produced. Such restrictions have led to legal challenges in the United States, sometime based on state law and sometimes based on antitrust laws. Horses can crossbreed with other equine species to produce hybrids. These hybrid types are not breeds, but they resemble breeds in that crosses between certain horse breeds and other equine species produce characteristic offspring. The most common hybrid is the mule, a cross between a "jack" (male donkey) and a mare. A related hybrid, the hinny, is a cross between a stallion and a jenny (female donkey). Most other hybrids involve the zebra (see Zebroid). With
A Donkey, 3 Rocks, and a Bird. of completion, plus the founder's mark for Will Willie. The Smithsonian Institution describes the work as abstract. Its condition was deemed "well maintained" by Smithsonian's "Save Outdoor Sculpture!" program in November 1993. A Donkey, 3 Rocks, and a Bird. A Donkey, 3 Rocks, and a Bird., also known as Donkey, Bird and Rocks and Donkey, Three Rocks, and a Bird, is an outdoor 1992 sculpture by Brad Rude, installed at Catlin Gabel School in West Haven-Sylvan, a census-designated place in Washington County and the Portland metropolitan area, in the U.S. state of Oregon. Brad Rude's "A Donkey, 3 Rocks, and