Hi,
There are around 20 primary mutations (see here:
http://www.mutavi.info/index.php?ref=symbols3 ) which can combinate to produce millions of possible combinations (20 x 19 x 18 x 17 x ..... x 3 x 2 x 1).
There are some mutations which can "hide" others. Ex: lutino inhibits melanin synthesis and thus will hide mutations acting on intensity of melanin (ex: dilute), distribution of melanin (ex: pied), ...
In some cases you can obtain unexpected results as when combining lutino and cinnamon which produces a bird still retaining some melanin (the true lacewing or ino-cinnamon combo).
Breeders do not "produce" mutations. Mutations appear spontaneously everyday in nature, but most of these mutations are recessive and they can pass through the generations for centuries without being visually expressed. When animals are kept in captivity, the number of possible mates for a bird is lower than in the Nature and it ends in some degree of consanguinity allowing these recessive mutations to be expressed. This is what happens in islands and allows a quick speciation.
Breeders can use inbreeding when trying to make appear mutations which are in the genetic pool of their animals. This is the way the first pied ringnecks appear in the USA. As you can see inbreeding does not produce mutations but just allow to express mutations which exist yet. The problem is that several genetic illnes are also recessive and consanguinity can also induce them to appear.
If you want to really "produce " new mutations you must expose your animals to genetic damage (X rays, alpha, beta or gamma radiations, chemicals, free radicals, ...) in order to induce new mutations. No one breeder would do such a thing, since to get just one ill mutant you will kill thousands of animals and induce illness in many others. Far more, probably the mutant you get would not be fertile at all.
There are animals with a genetic pool very stable and others which show a tendency to spontaneous mutations. The latest are those which adapt better to a new environement and present a quick speciation. I think that indian ringnecks belong to this type of species. If you look at the psittacula family (see here:
http://home.wanadoo.nl/psittaculaworld/ ... aWorld.htm ) you will remark that most of the different species share common features (ring, psitacine on wings, different head colour, clear spot in the tail, ...) and that insularity has allowed many of them to quickly speciate.
The ancestor of the psittacula family probably had a not very stable genetic pool allowing him to easily mutate and speciate. When I look at my indian ringnecks I am surprised to see how they are all differents, not only in colour, but in type of feathers, weight, tail, size, behaviour, ... it makes me think that the indian ringneck keeps the tendency to mutate of the lost ancestor and that he will produce far more mutations in the nexts years than those we know today; I also believe that in captivity he will evolve very quickly to a bigger size, even bigger than alexandrines. For me he is the BIG MUTANT.
Recio
PS Sorry if I was too "heavy", but I had too much free time.
