What does the F1 or F2 mean??

[José Guilherme Moreira]

Guys,

Thanks for getting this post alive and particularly thanks to the explanation that RD gave me (sorry, forgive me but I do not know how the private conversations work in this forum...) Well, he's absolutely right in one thing: the filial designations are not only for WC fishes but do apply to any breeding program.

RD pointed the flowerhorn hybrids as example, where the parents are not WC... By the way, many people also do not know that from a scientific approach even hybrids do also have specific taxonomic rules. It's the nothotaxa, from the greek words "notho" (that means "hybrid") and "taxis" (that means "arrangement") and those rules are different from the ones of the binomial system of nomenclature.

Anyway, what I meant to to emphazise was that we cannot accept the F0 designation. Even if it is widely used, it is not correct. Semantically it is wrong to use the F applied to the parents. If the F stands for "filialis" (descendants) the parents are not 0 ("zero"). What we are talking about here, with the "F" classification, is the descendants/siblings genealogical tree levels. The parents are not "filialis", they are "parentes" or "parentum". This was just my point.

 

[RD.]

You are absolutely correct, Jose. In Mendel's experiments he used P or parental generation, not F0. But it is far too late to unring that bell. Here in North America the F0 designation has been used to describe WC fish for as far back as I can recall.