06/19/2026
S*x linked coloring explained...
I think it's important for people to know that s*x linked genetics aren't exclusive to animals. Do you know why more men are color blind than women? It is s*x linked. What that means is it comes down to chromosomes.
Other than the alien platapus (ten s*x chromsomes) and other possible exceptions, most mammals go off X and Y chromosomes for s*x determination. Female is XX and male is XY. Birds go off Z and W chromosomes. It's flipped for birds with ZZ being male and ZW being female.
As to how the s*x linked part works from there, in genetics, the term "locus" is used which is Latin for essentially a "spot." It's the spot where the gene mutated that changes whatever attribute it is that is changed. In this case, the spot that mutated affects feather color. And the spot that mutated is only on one chromsome: Z
The Narragansett color spot is annotated with the letter "N." Two N's are used for the males which have two Z chromosomes (ZZ = NN). One N is used for the females typically with a "-" to show there is no other spot. I used "_" because I wanted to show it means there is nothing there to read, but I feel like the "-" is better overall... (ZW = N-)
Okay, so the next part. The "N" means the Narragansett spot, but the capital N would mean "Normal" or "No Mutation." Narragansett coloring is recessive and is marked by the little "n."
So, for a hen, there's only two options. N- or n-. She either has Narragansett color or she does not. She's not carrying Narragansett. She's not half Narragansett. It's either there or not there.
For a tom, there's three options:
- NN (normal - no Narragansett at all)
- Nn (carrying the mutation, but not showing it)
- nn (Narragansett)
So, if you follow the chart, Narragansett tom with Bronze hen makes all Narragansett hens and Bronze toms.