The tiger produces a hormone that sets the fetal liger on a pattern of growth that does not end throughout its life. The hormonal hypothesis is that the cause of the male liger's growth is its sterility — essentially, the male liger remains in the pre-pubertal growth phase. Male ligers also have the same levels of testosterone on average as an adult male lion. In addition, female ligers also attain great size, weighing approximately 320 kg (705 lb) and reaching 3.05 m (10 ft) long on average, and are often fertile. In contrast, pumapards (hybrids between pumas and leopards) tend to exhibit dwarfism.
Interestingly enough, ligers are the same size as the prehistoric American Lion.
Hercules and Sinbad
Jungle Island in Miami is home to a liger named Hercules, the largest non-obese liger, who is recognized by the Guinness Book of World Records as the largest living cat on Earth, weighing in at 400 kg (882 lb). Hercules was also featured on the Today Show, Good Morning America, Anderson Cooper 360, Inside Edition and in a Maxim magazine article in 2005, when he was only 3 years old and already weighed 408.25 kg (900 lb) at the time. Hercules seems completely healthy and is expected to live a long life. The cat's breeding is said to have been a complete accident. Sinbad, another Liger, was shown on the National Geographic Channel. Sinbad was reported to have the exact weight of Hercules. Hercules and Sinbad belong to the T.I.G.E.R.S. family of animal ambassadors, who put on the "Wild Encounters."
