> Gwen, thanks for sharing your learning! We must have read the same "stuff".
> I think that the white mare (pink skin) was the big "prize" for the
> Bedouins. Black is nothing more than a bay that is "really dark". More
Not true, true black (as opposed to "black bay" which is a bay horse that
is just really dark), sometimes called non-fading black would be a bay if
it had a gene that limited its black only to the points (i.e. mane tail,
feet, tips of the ears, etc. seal bays also have some black in their
coat, which is what a "black bay" or "really dark" bay is). This is a
dominat gene. So...if you don't breed a true black you wont get a true
black, you can get a "really dark" bay by breeding a seal bay to just
about anything.
> rare than the bay. How many "white" horses have you seen with pink skin?
> The only thing that is confusing is the "black/white" piece. I think the
> important thing to remember is that: bay = either BB (homozygous) or Bb
> (heterozygous). Chestnut = ONLY bb (homozygous). Grey can be BgBg or BgB or
> Bgbg or Bgb or bgbg or bgb. Upper case is always "dominant", lower case is
> always recessive. Maybe that better explains how it works. I still really
This WAY oversimplifies the genetics of coat color, since baying and
greying are not controlled by the same gene pair. As a rough rule, coat
color is controlled by one gene pair, baying is controlled by another
gene pair, and greying is controlled by another (this also
oversimplifies, but not quite so badly) so the coat color gene will tell
you the underlying color of the coat of the body, the baying gene will
tell you whether that color is over the entire body, or whether the horse
will have black point (and to what extent) and the greying gene will tell
you whether your horse of a different color will turn grey or not.
Chestnuts are recessive in all three of these, bays have atleast one
"baying" gene (and no greying gene), and greys will have atleast one
greying gene.
The nitty gritty (technical) details of this can be found in the book
_Equine Genetic and Selection Criteris_ (additionally, some magazines
that talk about breeding for color (e.g. Paint Horse Journal, and some
issues of Arab magazines that talk about breeding for black) will also
discuss this.
kat