Need Cross Breeding Scientific Explanation

[greenfish]

Ok. I need clarification on something. Now I know guppies for example are just different color variations of Poecilia reticulata so if you put them in the tank together they will cross breed. What determines if two different kinds of fish will cross breed? I mean the scientific name has two parts. I think one is a genus and the other is a species I get them confused. What if the fish matches on one but not the other? Is there danger of cross breeding? If the first part matches is that an issue? What about other fish that fall under a general family such as Tetras or rainbowfish or cichlids? I would like to keep all of the species I keep "pure" as I can so I wanted someone with more scientific knowledge to explain it to me so that I don't mix the wrong ones. TYIA

[Endgame319]

Hybrids dont have scientific names as they are usually unfertile. Only VERY close species can have fertile young. Ex. Endlers and guppies.

[greenfish]

Ok. But what about something like this?
Bolivian Ram - Microgeophagus altispinosa
German Blue Ram - Microgeophagus ramirezi
They are very similar fish but have different scientific names.

[Fruitbat]

greenfish....

You are correct in assuming that the first part of a binomial (two-part name) is the Genus and the second is the species. So...for the guppy....Poecilia reticulata, the Genus is Poecilia and the species is reticulata. Nice to see that you got the capitalization right too! The generic name (Genus) is ALWAYS capitalized and the specific (species) name is NEVER capitalized, even if it is a proper noun.

With that out of the way.....in GENERAL....member of different genera don't successfully interbreed, though this is not ALWAYS the case! It is not, however, particularly uncommon for different species of certain types of fish to interbreed and if you drop down to the subspecies level it is even more common. Most of the time (but not always) the offspring of interbreeding are sterile.

Keep in mind that the classification of organisms is an artificial system based on certain relatively constant and observable characteristics. Living things don't always understand that they're supposed to follow the rules set by humans!!

The results of interbreeding are usually called 'hybrids'. Endgame is right...hybrids do not have special scientific names. They are generally named according to the cross that created them. For example, a mule is a cross between a horse (Equus caballus) and a donkey (Equus asinus). Note that this cross occurs at the species level. The mule is then 'scientifically' named Equus caballus X asinus. If the two species of Rams you mentioned were to interbreed then you would have a hybrid fish named Microgeophagus altispinosaXramirezi.

[greenfish]

Ok so if it is the same Genus then there is a chance or cross breeding? Is the "safest" was to avoid hybrids to not mix fish of the same Genus? Generally speaking do similar fish of different Genus then not cross breed?

I appreciate all the info. I am learning more and more everyday

[greenfish]

Originally Posted by Fruitbat

With that out of the way.....in GENERAL....member of different genera don't successfully interbreed, though this is not ALWAYS the case! It is not, however, particularly uncommon for different species of certain types of fish to interbreed and if you drop down to the subspecies level it is even more common. Most of the time (but not always) the offspring of interbreeding are sterile.

Ok I re-read your reply Fruitbat and I think I answered my own question.

Thanks to you both I now have a greater understanding

[Fruitbat]

It is very uncommon for fish of different genera to cross-breed. The major exception in fish are the livebearers. There have been cases of Swordtails (Xiphophorus) breeding with Mollies (Mollienesia). If you're keeping tetras of different genera together (or even of different species as long as they don't closely resemble each other), the chances of cross-breeding are extremely unlikely at best!

[greenfish]

Thanks again