Cross Breeding

[BOG6ON]

G'day everyone,

I am looking for some facts about cross breeding. I have asked the question before and looked up some web sites but cant find any 'true facts'. I have read and been told that cichlids will cross breed with eachother when they look the same to each other, and i have also read and been told that they will also cross breed when they are the same 'Genous' (I think that is the right word) i.e. Lamprolongus, Haplochromis, Tropheous....

If any body has any info or knows where i can get some info on this matter it would be greatly appreciated!

Thanks.

Luke.

[genetik_defekt]

Can you tells us why you want this info? like are you trying to avoid keeping certain species that will crossbreed? is there a certain species you want to keep that you thing might crossbreed etc etc.

[BOG6ON]

Can you tells us why you want this info? like are you trying to avoid keeping certain species that will crossbreed? is there a certain species you want to keep that you thing might crossbreed etc etc.

Iam stocking up a 5x2x2 as a display tank with my breeders as i have shut down my fish room temporarely, and would also like to add some others. I just want to make sure the fish that i had in all seperate tanks before wont start breeding with each other once put together.

[Ant]

Why don't you post the species you have and people here on the forum should be able to tell you.

[Andrew]

Well, it's not a closely guarded secret - and I am sure you know the position of this forum and its members on the subject of hybridising - Hybrids = BAD

Suffice it to say that most members of a species flock have a high potential to crossbreed when left no option but heterospecific mates, even if they are more distantly related (as seen in the case of those mutant blood parrot thingies).

Offspring are most often sterile, but yes, they can be produced by a male of one species and a female of another.

I would recommend taking any steps you can to prevent this from happening. It does not matter which ones will cross with each other, just try to keep your species flocks separate, e.g. Lamprologines, Haplochromines, Mbuna, Guapotes, etc.

Of course, if any offspring are produced, please make sure they don't find their way to a LFS...

Cheers,

Andrew.

[BOG6ON]

It does not matter which ones will cross with each other, just try to keep your species flocks separate, e.g. Lamprologines, Haplochromines, Mbuna, Guapotes, etc.

I am not trying to find out what fish will cross breed with each other i am trying to find out why they do! Is it because they are simular shapes and sizes, there for the fish think they are all the same, or is it because they are the same species? Or is it something else or all of the above?

[mattrox]

They cross-breed because they have the biological urge to breed. If there are no females of their type they will breed with which ever females let them. Some times female fish are attracted to the most dominant male in the tank even if they have thier own male.

My greyshakei male would breed with the johanni female and stop the johanni male from breeding. The I grew the fry a little as turtle and venustus food.

Most people who keep mixed tanks only keep the fry if they see the correct fish breeding. The best way to minimise it in a mixed tank is to have 2m/5f in a group, the males have a choice of females and vice versa.

I don't subscribe to keeping the flocks seperate, that is such a broad sweeping statement, they are less likely to cross breed so that is not really an issue. It is about constructing a stable habitat where agression is controlled. And having enough open space for the haps/peacocks to swim.

[Cichlabxr]

This is a very difficult question to answer. Basically if they are not genetically isolated they can breed. As to why? 'cos they can??? Studies are being done constantly to better understand this. Be prepared to do a lot of reading!!!!

Hybrid (biology)

Practical Genetics for Aquaculture

Published Online: 14 Jan 2008

Editor(s): C. Greg Lutz

Print ISBN: 9780852382851

The book listed above would be a good place to start.

Onlinebook

Few speciation genes have been found. They usually involve the reinforcement process of late stages of speciation. In 2008 a speciation gene causing reproductive isolation was reported.[16] It causes hybrid sterility between related subspecies.

A central goal of evolutionary biology is to identify the genes and evolutionary forces that cause speciation, the emergence of reproductive isolation between populations. Despite the identification of several genes that cause hybrid sterility or inviability—many of which have evolved rapidly under positive Darwinian selection—little is known about the ecological or genomic forces that drive the evolution of postzygotic isolation

A Single Gene Causes Both Male Sterility and Segregation Distortion in Drosophila Hybrids

Nitin Phadnis* and H. Allen Orr

A species has been defined as a phylogenetic continuum that has become so differentiated that it has lost the ability to procreate with other life forms that have taken different evolutionary courses. At some point in its evolution every species has to have passed through a stage known as subspeciation, when it constituted a population that was beginning to evolve in a new direction but still had not lost the ability to procreate with other populations of similar ancestral origin. The emergence of different subspecies would generally be due to geographical isolation under different environmental selective forces. No speciation can take place if emerging subspecies lose their identity by merging their genes with other related subspecies before they have become so differentiated that they have lost the ability to cross-breed, or in other words have evolved into different species. Genetic isolation is an essential prerequisite for evolutionary speciation.

J. W. Jamieson

Regards,

Martin