Originally Posted by tonic
Yes it is
Sex-linked female is an exceptional case to understand its genetic makeup and hereditary behaviour letís see this in simplest way
X chromosome (autosome): contains everything such colour, variety, shape etc = X
Y chromosome (allosome or sex): is smaller and only determines the gender = Y
Phenotype: The colour budgie shows
Genotype: The colour budgie carries in hidden form
Pure Budgie: Budgie having same phenotype & genotype is called pure budgie. Genetically pure Green Budgie = X(green) X(green)
Impure budgie or Split: When phenotype & genotype of a budgie is different the budgie called impure budgie or split. Genetically Green budgie split to blue = Green/Blue = X(green) X(blue)
Now look at the genetic makeup of sex-linked recessive female
For example Cinnamon Female = Xcinnamon Y(no colour or variety only gender) = Xcin Y
1. Can you say this budgie is split or can be split? Genetically sex-linked females cannot be split because the variety exists only on X chromosome and Y chromosome only determines the gender.
2. Being sex-linked recessive why in case of Male Normal/Cinnamon x Female Normal = 25% Cinnamon Females
This is because when itís a female and sex-linked gene is on X chromosome it will appear therefore it is said that hens cannot be split to any sex linked variety and because of this being recessive variety it appears in case of normal/ sex-linked males x normal females.