Horse
Depending on breed, management and environment, the modern domestic horse has a life expectancy of 25 to 30 years. Uncommonly, a few animals live into their 40s and, occasionally, beyond. The oldest verifiable record was "Old Billy", a 19th-century horse that lived to the age of 62. In modern times, Sugar Puff, who had been listed in "Guinness World Records" as the world's oldest living pony, died in 2007 at age 56.
Peruna
Following the death of Peruna I, W.E. Culwell (owner of Culwell and Sons) began a tradition of supplying SMU’s mascot. The Culwell family has donated and cared for Peruna II-Peruna IX. According to Culwell’s son, C.W. ‘Cully’ Culwell (’54), “He (Dad) would go to every game and serve barbecue to the players after the game; he really loved the school….Dad donated a Shetland pony because they have a greater longevity than a Quarter Horse.” (Shetlands will normally live 25 years or more, while a Quarter Horse will only live 15–18 years.) His generosity continued until his death in 1964 and has been continued by the Culwell family. Until 1993, the mascot was stabled on the Culwell Ranch in Grapevine. Since then, the stabling location has been kept a secret. To date, nine mascots have represented SMU…seven stallions and two mares, although hard-core types prefer all-black stallions because of their alleged vitality and spirit. When Cully Culwell was having difficulty locating a black stallion to replace Peruna VI, he shared, “stallions are hard to obtain now because most young male horses are castrated to make them tamer….a stallion which is more aggressive, better represents the spirit of the SMU Mustangs.”