black tabbies

[Lady Ten]

ailuronymy.tumblr.com/post/30914574996/have-you-ever-seen-a-black-tabby

There's been some discussion of this on Ailuronymy recently. Do black tabbies exist? If so, what do they look like, and how are they possible?

ailuronymy.tumblr.com/post/30922521984/for-the-anon-all-black-cats-are-technically-just

for the anon, all black cats are technically just really dark brown tabbies. If you look at them in the sun you can sometimes see their stripes when they're really young

I don't know what sort of genetics would be responsible for the difference between regular brown tabbies and "really dark brown" tabbies, so I'd like to hear more of the reasoning behind this statement. As I understand it, a "black tabby" is really the more technical name for what's also called a brown tabby, possibly since it's a result of the gene for black combined with the gene for striping, but I don't know much about how color "brightness" is determined. Anyway, I doubt all black cats are dark brown tabbies, though I don't have the expertise to say.

ailuronymy.tumblr.com/post/30922592666/black-tabby-anon-they-do-exist-but-theyre-very

They do exist, but they're very rare. I had one once, but, sadly, the only pictures of her are blurry and of her very far away. I don't think I've ever seen a cat like her, and it occurs to me now that she must have been very rare, indeed. She was a pure black cat, not a charcoal black but dark enough to not be considered grey, with really pure black stripes. It's hard to explain, but I assure that they are real.

Once, when arguing with people on neo, I came across someone arguing for the existence of "black tabbies" described like this. I basically said "pics or it didn't happen," and the other user showed me this:



Now, I'm not sure whether this is just a "really dark" brown/black tabby, or a "black cat" with ghost striping, as wikipedia calls it here.

Thus, the non-agouti genotype (aa) masks or hides the tabby pattern, although sometimes a suggestion of the underlying pattern can be seen (called "ghost striping"), especially in kittens.

Or maybe those are both the same genetic situation described different ways; I don't know, but clearly something's going on here.

[vbfdoee]

I've seen nothing to suggest that black cats are really just very dark brown; here's the way the genetics of black versus brown fur works as I understand it.

At a certain point, you have a gene encoding whether a cat will be brown or black. Black fur is indicated by the dominant form B, while brown is indicated by the recessive form b. The two of these are mutually exclusive.

However, each cat has two copies of this gene. Dominant means that if a cat has one B copy and one b copy, the dominant form will mask the recessive one and the cat will be black. In real life, though, it's not so simple. It seems that if a cat is heterozygous (it has one B and one b), it will be a more "rusty", brown-tinged black, while homozygous cats (two Bs) are more blue-black. If a cat has very prominent ghost striping, which all non-tabby cats have to some degree, in addition to being heterozygous, it may well appear to be a "black tabby".

As for the second quote, I'm enough of a scientist that I don't trust anecdotal evidence alone.

[di bateman]

I have 2 of the little darlings, one has stripes and one has spots and are so beautiful