The Blue Tiger Sightings

In September 1910, Harry R. Caldwell, a hunter and missionary saw a bluish-gray ground color and deep blue underparts object which he at first took to be the blue in a man's clothes. On second look he found that the blue was the body of the tiger. He saw it near Rongcheng area, Fujian Province, China. Caldwell described it this way: "The markings of the animal were marvelously beautiful. The ground color seemed a deep shade of maltese,
changing into almost deep blue on the under parts. Well-defined black stripes over a grayish-blue ground color. Deep blue on chest and ribcage, and so far as I was able to make our similar to those of a tiger of the regular type."
 

He had it in his rifle sights but could not pull the trigger because there were two young boys nearby who might be endangered. By the time he changed position, the tiger had slipped away. Caldwell said other sightings of the Blue Tiger were reported from the same region, but that was to be his only sighting of it.

According to Bernard Heuvelmans, these large Blue Tigers have been "persistently" reported from China since the 1920s. Heuvelmans suggests that the color in Blue or Black Tigers may be caused by melanism. Karl Shuker also suggests a Tiger (Panthera tigris) may have possessed a recessive melanistic mutant allele and a recessive dilute mutant allele to produce a morph called a “blue dilution.” Because no official verdict exists and we know relatively little about the animals, these large cats remain cryptids.

According to Esther Inglis-Arkell, Tigers have the agouti gene, a gene that determines whether animals - from dogs to horses, have patterned fur. It causes a range of pigmentation patterns in dogs and cats, as well as the darkening that is sometimes seen around the ears and lower legs of horses. A blue or maltese tiger, would have to have a combination of the agouti gene with the dilution gene. The agouti gene would give the tiger stripes, but the dilute gene would wash out the orange and turn it gray.

Sources:
Cryptozoology A to Z : "The Encyclopedia of Loch monsters, Sasquatch, Chupacabras, and Other Authentic Mysteries of Nature" by Loren Coleman & Jerome Clark;

Mysterious Creatures : "A Guide to Cryptozoology" by George M. Eberhart;

http://io9.com/could-the-mythical-blue-tiger-actually-exist-1331164937

Pic Source:
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