exactly - the father provided the "orange" gene, the mother provided a "non-orange" - therefore the females were both mixed; however the males got only their mothers non-orange x chromosomes, so were NOT ginger. the only way a male can be an actual calico or tortie is if he is genetically abnormal - either a mosaic of xx/xy or multiple-xy (xxy or xxxy) All those conditions lead to male sterility. An occasional "male" calico has on closer examination proven to be actually a freemartin - genetically female but due to developmental conditions in the womb, externaly male. Cross a calico or torti female with a ginger tom and you will statistically get 1/4 female ginger, 1/4 male ginger, 1/4 male not orange, 1/4 female calico/torti. Of course there are several competing definitions of both tortoiseshell and calico. Under one system tortoiseshell is the mixed condition with tabby markings present and calico the colours are solid. In the other system the mixed orange/not orange condition is tortoiseshell whether or not the markings are solid and the addition of white spotting makes it a "calico" It gets even more complicated because genetically you cannot actual have a solid "orange" cat the gene that surpresses the markings in the darker pigment does not effect the orange pigments- the tabby markings are always present, but other modifiers can either widen or narrow the stripes so they are not apparent. Another interesting point - virtually every colour mutation present in the house cat has been observed at some point in "large cats" - And let me tell you - a tortoiseshell tabby Tiger is something to behold!!!!!
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