The liger is a hybrid cross between a male lion (Panthera leo) and a tigress (Panthera tigris). Thus, it has parents with the same genus but of different species. It is distinct from the similar hybrid tigon. It is the largest of all known extant felines.
Ligers enjoy swimming, which is a characteristic of tigers, and are very sociable like lions. Ligers exist only in captivity because the habitats of the parental species do not overlap in the wild. Historically, when the Asiatic Lion was prolific, the territories of lions and tigers did overlap and there are legends of ligers existing in the wild. Notably, ligers typically grow larger than either parent species, unlike tigons which tend to be about as large as a female tiger.The liger is often believed to represent the largest known cat in the world.Males reach a total length of 3 to 3.5 m, meaning they are the size of large Siberian tiger males. Imprinted genes may be a factor contributing to huge liger size. These are genes that may or may not be expressed on the parent they are inherited from, and that occasionally play a role in issues of hybrid growth. For example, in some dog breed crosses, genes that are expressed only when maternally-inherited cause the young to grow larger than is typical for either parent breed. This growth is not seen in the paternal breeds, as such genes are normally "counteracted" by genes inherited from the female of the appropriate breed.