Some 'tabbies' ('leucistic' is a more accepted phrase) are ugly, but I agree with your niece that Diamond is a beautiful boy, as well as a devoted brother to his twin sister!
Panthera Puss -- thanks for the genetic stuff, which is fascinating; however, I agree with a later suggestion that Golden Tabbies are not exactly leucistic. A leucistic animal [hope I've got this right] is one with greatly reduced melanin all over, so it appears a 'diluted' version of the normal.
Leucistic is derived from the greek word leukos, meaning white. I usually refer to white tigers as leucistic (or anerythristic), but certainly not the thing above. I would suggest that hypomelanistic (reduced melanin) might be a better term.
The 'white' gene is known as Chinchilla Albinistic - it basically represses yellow & red pigmentation.
'Leucism' is a phrase Diamond's zoo uses - I don't have an opinion either way on the technical correctness, though I take it to just mean 'more white than usual' in this context. I think the zoo are trying (in their use of the phrase) to balance out more unofficial or affectionate phrases such as 'Tabby', 'Marmalade' or 'Strawberry' for this type of tiger which animal people don't always like - and they do take advice from at least one very good authority.
Interestingly, there was to be a colony of 'Tabby' tigers reported in the wild, which died out sometime in the 19th or early 20th century I think. It has been mooted that these tigers were a genetic adaptation to local red soil conditions, but it seems more likely they were rather an inbred population, (like the white lions of Timbavati, I guess).
“An example of a golden tiger is in Dreamworld in Australia. Samara, a normal orange tigress, had been mated with nearly-stripeless white male tiger, Mohan. Her litter included one normal orange cub (Sultan), the first white tiger born in Australia (Taj, also nearly stripeless), and the first two tabby-colored tigers (male Rama and female Sita) born in Australia.”
I don’t know the genetic history of the mother (Samara) but she obviously carried the recessive allele (heterozygous) to produce a white cub (Taj), without expressing the white phenotype herself.
The father, Mohan, was a very impressive looking male. I’ve heard he had Siberian genes but I’m not 100%. He had a lion like ‘mane.’
