Various hybridisations amongst cats occurred back in the days when zoos particularly wanted oddities to attract the public. These date back as far as the 1800s, when zoos were more menageries designed to turn a profit rather than carefully controlled attempts at animal conservation.
Cross-breeding in India was first recorded in 1837 when a Princess of the native Indian state Jamnagar presented a hybrid big cat to Queen Victoria.
In Europe, hybridisation can be traced back to before the First Great War, when German Carl Gottfried Hagenbeck carried out experiments with big cats and then noted that the males were likely to remain sterile.
More common hybridisations in big cats:
Cross-breeding can and does occur between lions and tigers. The hybrid offspring are known as ligers or tigons, with the nomenclature depending on the mating species. The usual format is to place the male parent first in the name. Lions have also been mated with leopards producing leopons and various other combinations have produced more unusual animals. These are all covered in other articles within this section of the site.
Hybrid animals almost certainly only exist in captivity and are the result of human intervention, along with the unnatural living circumstances presented by captivity, and on occasion, artificial insemination. It is often thought that the majority of hybrid cats come about through artificial insemination, but that is far from correct. This medical procedure has a very low success rate in big cats and was mostly practiced in early hybridisation experiments.
Hybridisation in the wild:
It is extremely rare for any wild animal to breed with one from another species.
For instance, in the wild the Grant's and Thompson's gazelle live together happily in mixed herds. The species are very alike and only experts are able to discern one from the other. Despite this there are no known instances of these gazelle interbreeding.
The domestic dog will mate indiscriminately with another breed, but wild dog breeds, including wolves, foxes and coyotes, mate only within their own species.
There are, however, several types of small wildcat which do interbreed freely with
the domestic variety.
Amongst big cats, the relatively unknown marozi is popularly thought to have been an example of natural cross-breeding between the lion and the leopard. Then again, there are several other explanations which could also account for this spotted lion.
In the early 1900s, Indian natives regularly spoke of an animal they knew as the doglas. It was claimed to be a hybrid between the leopard and the tiger. Though there were some large leopards in the area with striping on their abdomens, it was never established that the native claim accounted for the source of this odd colouring.
Throughout Mexico and South America there is a widespread belief that natural hybrids occur between pumas and jaguars, but animal biologists have been unable to find evidence which would substantiate this.
Legal designations:
Hybrids are designated according to their parentage into either the category of a domestic animal, or that of a wild animal.
All crosses between wild and domestic animals are automatically considered to be domesticated. This includes animals like the beefalo (American bison x domestic cattle), Zorses (zebra x horses), zonkeys (zebra x donkeys), the wolf dog, and the various small wild cat x domestic cat hybrids.
Any cross between two wild animals, for instance, a liger, tigon, or leopon, is still considered to be a wild animal.
These distinctions become very important for prospective owners applying for licenses and meeting containment requirements.
Sterility in hybrid animals:
Hybrids are usually considered sterile, and sterility is a natural biological barrier against hybridisation occurring. There are rare situations where nature has proven the sterility rule not always correct and this has resulted in such beasts as li-ligers and ti-tigons.
Despite the rarity of natural hybridisation, and the even lower chance of fertility, we know it definitely happens, and frequently enough that over many thousands of years evolutionary change can come about.
When the built in protective mechanisms preventing successful breeding break down the opportunity for a new species to develop opens up. Perhaps a good example of this is the mule. Usually considered to be infertile from 1527 to 1990 around 60 live foals were reported as being born to mules. The claims were widely spread and came out of Europe, the U.S.A, South America, North Africa and China. Though the number of reports is minute compared to the amount of mules, over many thousands of years this could conceivably result in an entirely new species.
All reported fertile mules were females, and this has also been the case with all fertile hybrid big cats. All dissected males have all been confirmed as infertile.
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