Note: this page was written mainly round 1998 and 1999, and I stopped updating it round
2000. The last cat on this page, Lilac, died on
10 August 2015 at the age
of 18½. I'm now keeping photos of our cats on our domestic animals page.
In a previous life, I used to breed cats. I had a particular liking for Burmese and
Siamese, and after returning to Australia (and reluctantly leaving behind my all-time
favourite cat, Queenie (Reine de Saba vom Hohen Roß)), we bought two Burmese, a
chocolate male whom we called Choc, and a lilac female called Lilac.
One of the things that interested me about breeding cats was the genetics. In cats which
have neither stripes nor blotches, four genes are responsible for the appearance of the cat:
The C (coat) gene is responsible for the general appearance of the cat. There
are a number of alleles:
C, the imperfectly dominant allele, is also the normal gene. Cats with this gene
are called self-coloured. For example, a black cat will always have at least two
C genes.
The cc gene is found only in Chinchillas.
The cb gene is found only in Burmese (the subscript b means Burmese).
The cs gene is found only in Siamese (the subscript s means Siamese).
The ca gene is found only in albinos. There are currently no
recognized breeds of albino cats.
The B (black) gene controls one of the colour attributes.
B, the dominant allele, is also the normal gene. For example, a black cat will
always have at least one B gene.
b, the only recessive allele, is also called brown. It's very rare except in
orientals. In Burmese, it gives rise to the colour called chocolate, in Siamese
chocolate point, and in self-coloured cats it's called Havana.
The D (dilution) gene controls another of the colour attributes.
D, the dominant allele, is also the normal gene. For example, a black cat will
always have at least one D gene.
d, the only recessive allele, is also called blue. In most cats, it causes the
coat to take on a greyish colour, which cat breeders call blue. Burmese blue are
somewhat lighter in colour than self blue, and Siamese blue point are decidely lighter
than others. Some breeds are only blue, such as the British Blue and the Korat, both of
which are self-coloured (at least one C gene).
With these three genes we get a three-dimensional matrix of colours. Here it is flattened
by dividing it according to the C gene. I omit the Chinchillas (which I don't know
well enough) and the albinos (which nobody knows). What we get is:
Self-coloured cats (C)
B
b
D
black
havana
d
blue
lilac
Burmese cats (cb)
B
b
D
brown
chocolate
d
blue
lilac
Siamese cats (cs)
B
b
D
seal point
chocolate point
d
blue point
lilac point
There's also a fourth gene, O, which is responsible for red (“ginger”),
cream and tortiseshell cats. It's interesting because it's located on the X chromosome, and
it's imperfectly dominant, so its behaviour depends on the number of X chromosomes a cat
has. This explains why tortiseshell cats are all female. Maybe I'll expand on this some
day.
Finally... my cats
So, now that you know what we're talking about, you'll understand our cats. Sadly, of the
four that I describe here, we only have one left, Lilac. Choc was run over in February
1999, and Monty was run over in November 2000. We gave Maddi to a friend of ours in Winter
2000 after the cats had been having some differences of opinion, and after a few weeks there
she disappeared. We don't know whether she got bitten by a snake, run over (unlikely),
stolen, or whether she just decided she liked the outdoor life (which is possible).
Choc was a chocolate Burmese ((cb/cb, b/b, D/d), and Lilac is a lilac
Burmese ((cb/cb, b/b, d/d). How do we know that Choc is heterozygotic
in D? His father was a lilac, and Lilac is his littermate. Here's Choc:
I was travelling in Singapore in April 1998
when Yvonne called me and said she'd found a
male Havana kitten which she wanted. I'd always said “we need two, in case one fails,
but that's enough”, but Yvonne persisted. Then I discovered he had a lilac sister,
and I was convinced. Why? The symmetry:
Our cats' genetic makeup
C
cb
D
Monty
Choc
d
Maddi
Lilac
The symmetry doesn't go as far as the naming, though: Havana is the name given to a brown
Oriental Short Hair, and the lilacs are just called lilac Oriental Short Hair. We had
trouble with the naming, of course, since we already had a Lilac, so we kept their pedigree
names (after abbreviation): Monty (Monticello) and Maddi (Madison). Here's Maddi:
These photos were taken in June 1998 with
my
Casio QV-5000 SX digital camera. It lasted about 8 months before dying, and the
repairers don't seem to be interested in doing anything about repairing it, so I'm back to
using my Pentaxes, which I find give better photos anyway. When I developed the film in
number 2 Pentax, I discovered some photos which were taken earlier. Here they are:
From top right, we have Choc, Maddi, Lilac and Monty.
When this picture was taken, Maddi and Monty were a little less than 6 months old. You'll
notice how similar the coat of Lilac and Maddi is, but Monty is much darker than Choc
(except on the nose, where the colour is the same). You'll also notice the silvery quality
of the lilac coat.
Finally, here are some photos taken in May and June 1999. Choc had been gone for a while,
and Maddi and Monty were fully grown (and larger than Lilac).
After Monty got run over in November 2000 we decided not
to get any more cats. It was just too painful to see them get killed.
Well, we held out for four months. Then our neighbour Diane Saunders found a starving kitten in her shed, apparently dumped there. At the
time I wrote:
I put it between 8 and 10 weeks, and not in nearly as poor a condition as she had suggested.
It looks like a pure bred cat: long-haired tortoiseshell chinchilla, not the kind of moggie
you see every day. The red looks more like cream, which suggests double dilution (see above;
blue or lilac cream), but the dark hair looks more black than blue. If she really is double
dilute, you'd expect her to be pure bred, since she would need two parents with the
d gene, and it's pretty rare except in pure-bred cats.
We decided to call her “Perdita”, meaning “lost”, after the name in
“The 101 Dalmatians”. Here's a photo we took of her the day after she was
found.
The cream wasn't cream after all, it was red. I forgot how long it takes for the red
colour to develop, and until it does, it looks cream.
“Perdita” does not mean “lost” in Italian, it means
“loss”. The correct word would be “perduta”, but we didn't like
that name, so we ended up calling her “Fluffy”.
Greg Edmonds told me that he had seen wild cats which looked like Fluffy.
We now believe that she was a kitten (quite probably the only surviving one) of a feral cat.
That would explain how she came to be so far from civilization. We're uncertain what
happened to her mother. One theory I had was that she had been poisoned: at the time we
found her, the neighbours had been spreading rabbit poison. On the other hand, rabbits and
cats don't eat the same sort of thing. I'm coming to the conclusion that the most plausible
explanation is that her mother was scared off by Diane arriving in the shed, and ran away.
Diane found the kitten and took it away.
Fluffy's an interesting cat. She's not overly affectionate and tends to keep to herself.
She's also terrified of visitors, so few get to see her. Despite her presumed background,
she's a lousy hunter. Lilac keeps trying to teach her how to catch mice, but she just plays
with them until they run away. She obviously missed some crucial childhood training.
Here's a photo of her with Lilac, taken on 31 January 2004:
