I've seen a few discussions on the net about marbled peacocks, people are accusing them of being hybrids without a scrap of evidence, and after a bit of research I cant find a hint of evidence showing they could be hybrids, in fact everything points in the opposite direction, that they are likely to be a genetic variant created through inbreeding.
They are accused by some of being a peacock crossed with either marbled zebras and/or trewavasae, but these fish have very different shapes, so if they were hybrids we should see some variable fry sharing features from both species, and considering the accused fish are all from different genus groups, creating a fish that breeds true from crossing these different genera would be difficult, and probably impossible, though would need to check this with a scientific expert in fish genetics.
If you have bred them can you share what the fry looked like? did the fry grow true to form when it comes to head and body shape? i.e. did the fry look same shape as the parents? obviously the colours are variable, but its the shape that will give it away.
What we should see if it was a hybrid
If it was a hybrid then we should be seeing some fish that share mixed features with both species used to form the cross, overseas breeders could be culling to avoid the fish that don't match peacock shape, but its unlikely because it wouldn't be a viable fish to breed if it was a hybrid that needed to be uniform peacock shape, because they would loose too many fish and culling would be too time consuming for such a cheap fish that breeds in low numbers per female.
Local breeders can also help by sharing wether they noticed any variance in the shape of the fry.
Take a note of the difference of the head and mouth shapes in particular, if these were hybrids you should see a percentage of fish showing mixed traits.
Marbled peacock
Marbled Metraclima/Zebra
Marbled Trewavasae
Why they are most likely a genetic varient
1. Thousands of marbled peacocks sold in the industry all seem to be of a uniform peacock shape, though different fish farms may have cultivated their own marbled strains through the use of selective breeding a specific peacock species different to other farms.
2. There are several or more blotched fish species(e.g. M. zebra and P. trewavasae) occurring naturally in the rift lakes so its highly possible that many species in the rift lakes carry recessive genes for marbled pattern from a common ancestor in the lake.
3. Marble pattern genes are locked away within many fish species and it seems to be unlocked through selective inbreeding, countless common species are available in the aquarium trade which are known to be non hybrids, all created through selective breeding of a single species.
Marbled convict cichlid
Marbled angel fish
Marbled livebearers such as guppies, platys and mollies
Flowerhorn breeders after more than 10years have been unable to create a fixed strain of hybrid, the hybrid fish throw a mix of fish of shapes, sizes colours and patterns completely ununiform, so to me the chances of the marbled peacock being a perfectly fixed hybrid strain is pretty slim to none. Overall the evidence available to me is that they are very unlikely to be a hybrid and are most likely to be a selectively bred genetic mutation, but it would help as discussed above if any locals have bred them and can share what the fry looked like.
Cheers
Den
Edited by Den, 06 June 2011 - 08:40 PM.