Silver dapple

Crossing two of them

What it looks like on each base

Its gene carrot

Gene key

horsegenetics.silver

Alleles

Z z

Outcomes

wild, silver

Shows when

Z/z, Z/Z

Default allele

z

Wild frequency

1 in 60 per allele

Founder draws

1 × nextFloat()

Deterministic

yes

body

keepRed 0.90, keepBlack 0.46, tint 0.30 — chocolate

mane / tail / ears

keepRed 0.40, keepBlack 0.10, tint 0.28 — flaxen

The whole gene

boolean hair = part == Part.MANE || part == Part.TAIL
        || part == Part.LEFT_EAR || part == Part.RIGHT_EAR;
f.dilute(px, py,
        hair ? HAIR_KEEP_RED   : BODY_KEEP_RED,     // body barely touches red;
        hair ? HAIR_KEEP_BLACK : BODY_KEEP_BLACK,   // the mane pulls red down too, so it
        hair ? HAIR_BLACK_TINT : BODY_BLACK_TINT);  // leaves the dark-red corner - flaxen

On the body silver keeps almost all the red and just cuts the black, so a black horse’s eumelanin walks to a warm chocolate. The mane, tail and ears pull the red down as well, so the sample leaves the dark-red corner of the gradient and comes out flaxen rather than chestnut — the light mane on a dark body that names the gene. (v1 kept red at 1.0 on the mane and it came out a reddish chestnut instead.)

MCOA — the eye defect that rides along

A homozygous silver carries multiple congenital ocular anomalies: cysts and a malformed cornea, and a horse that sees badly. The mod has no vision for a horse to lose, so it is priced the way every sub-lethal disorder here is priced — two hearts. It shows in the info panel and the paper dump by name.

Only the homozygote. A single copy gives the whole coat with none of the defect, which is exactly why the disorder survives in a real population: the gene people breed for is the gene that hides it. Machinery on the horse’s body.

Why it runs after agouti

Silver only has something to do once the black points exist, so in Genes.naturalOrder() it sits immediately after agouti: agouti paints the mane / tail / leg black, silver then lightens it. Put the other way round and a bay’s mane would be re-blackened after silver had already flaxened it.