At first glance, sex-linked traits are more complex than
autosomal traits. However, once you get the hang of them, they are
actually easier to follow. Quaker mutations that are known to display
sex-linked inheritance are the Pallid (Dark-Eyed Cinnamon) and the
Cinnamon (Red-Eyed Cinnamon) traits. Though the only Lutino mutation
identified to date is autosomal recessive, it is expected that a Lutino
mutation will be identified as it has in many other species that
manifests this inheritance. These two types of Lutinos are
distinguished in other species by calling one "sex-linked Lutino" (SL
Lutino) and the other "non-sex-linked Lutino". (NSL Lutino)
The difference between autosomal genes (traits) and sex-linked genes
(traits) is that the former occur on the numerous pairs of autosomal
chromosomes and the latter occur on the single pair of sex chromosomes.
The reason why sex-linked genes (traits) are inherited differently
is because, unlike autosomal chromosomes, the cock and the hen don't
have similarly paired chromosomes. In fact, that is exactly what makes a
cock a cock and a hen a hen. The cock has a pair of equal sized sex
chromosomes which are designated with the letter "X".
Cock's Chromosomes
However, the hen only has one copy of this "X" sex chromosome. Her
other sex chromosome is much shorter and is termed the "Y" sex
chromosome.
Hen's Chromosomes
Any bird with a "XX" pair of sex chromosomes is a cock and any bird
with a "XY" pair is a hen. If you think of gender as a "trait", we can
use a Punnett square to determine the gender of offspring from any cock
("XX") and any hen. ("XY")
The chicks are what we all know to be 50 % "XX" (cocks) and 50 %
"XY". (hens) You can see that it is the hen that determines the sex of
the offspring by contributing a "X" or a "Y" to the cock's constant "X"
chromosome contribution. This is just the opposite in humans where the
man determines the gender of children. Also notice that ALL hen
offspring get their "X" chromosome from their father. (since they HAD to
get their "Y" which makes them a hen from their mother) And, finally,
note that ALL cock offspring ALWAYS receive their mother's only "X"
chromosome. (because if he got the "Y", he would be a she) We will
revisit these last two points later.
The cock's "XX" pair of sex chromosomes have normal pairs of genes
as discussed in the previous sections. In the hen's XY pair, the genes
on the lower half of the "X" chromosome are paired with the genes on the
"Y" chromosome. However, there are no genes on the "Y" chromosome to
pair with genes on the upper half of the "X" chromosome. So, genes
(traits) that reside in the upper half of the "X" chromosome (above the
pink line in the diagram below) are paired in cocks and remain as single
genes in hens. These genes (above the pink line) are what are known as
"sex-linked" genes. Those below the pink line will be ignored in this
discussion.
Sex-Linked Genetic Notation:
Genetic notation for sex-linked traits is a little confusing. The
"X" and "Y" notations are used to allow the sex of the offspring to be
identified. A superscript following a "X" indicates that letter as a
sex-linked gene. (trait) We will use the superscript "P" for the normal
green trait and "p" for the Pallid (Dark Eyed Cinnamon) trait. Thus,
XP+ stands for the green trait at the sex-linked pallid site and Xp
stands for the pallid trait at the sex-linked pallid site. The "Y"
chromosome never has a superscript since sex-linked traits only occur
above the pink line where the "Y" chromosome can't have a gene. "Y" is
used alone to convey information about the sex of the bird and as a
place keeper to remind us that there is no second gene for the hen at
that site. Some examples of notation should clarify this. These are
ALL the possible genetic combinations for the green and pallid traits.
XP+XP+
XpXp
XP+Xp
XP+Y
XpY
|
=
=
=
=
=
|
Green cock
Pallid cock
Green/Pallid cock
Green hen
Pallid hen
|
As you can see, all the birds with "XX" are cocks (regardless of the
genes they carry) and all of the "XY" birds are hens. Also note that
the pallid trait is recessive to the green trait since a "XP+Xp" bird is
visual Green split for Pallid. And, finally, it's clear that a hen can
NEVER be split for a sex-linked trait since she has only one copy of
the gene. She is either Green or Pallid.
Single Gene Sex-Linked Inheritance:
Understanding how to describe Green and Pallid birds in notation
allows us to use a Punnett square to predict some outcomes. Let's first
practice with a Green x Green pair just to get familiar. Once again,
the cock's possible contributions are tinted blue and the hen's possible
contributions are tinted pink.
50 % of the offspring are Green cocks
50 % of the offspring are Green hens
You can see that the addition of the superscripts has not changed
the way the "X" and "Y" chromosomes fall out. They are just as in the
example above giving 50% cocks and 50% hens. In this case, all the
associated genes are green, so all the offspring are too. Now, let's
try a Pallid cock x Green hen.
50 % of the offspring are Green/Pallid cocks
50 % of the offspring are Pallid hens
Three things become apparent now. First and foremost, the color
results of cocks and hens is different with sex-linked traits. With
autosomal traits, no mention of gender was made because whatever colors
resulted, they would be evenly divided between cocks and hens. Now that
the sex chromosome is involved, though, things are different.
Second, you can see clearly now that it is the cock that determines
whether the hen offspring inherit a sex-linked (pallid) trait.
And, third, all you would need to do with this pair is to look at
the visual color of the chicks, and you would know, FOR SURE, their sex.
All Green chicks are cocks which are split for Pallid and all Pallid
chicks are hens. Let's reverse this cross with a Green cock and a
Pallid hen.
50 % of the offspring are Green/Pallid cocks
50 % of the offspring are Green hens
Once again, the color of the offspring is dependent on their gender
(cocks are genetically different than hens) and the cock has determined
whether the hen offspring are Pallid or not. It is also clear that the
cock offspring inherit one of their father's "X" genes and MUST inherit
their mother's only "X" gene. So, the make-up of cock offspring depends
on input from BOTH parents contrary to that of hen offspring which only
depends on input from their father. Our final example will be a
Green/Pallid cock x Green hen.
|
XP+
|
Y
|
|
XP+
|
XP+XP+
|
XP+Y
|
|
Xp
|
XP+Xp
|
XpY
|
25 % of the offspring are Green cocks
25 % of the offspring are Green/Pallid cocks
25 % of the offspring are Green hens
25 % of the offspring are Pallid hens
Once you get used to the superscripts, sex-linked traits are no more
difficult to predict than autosomal. In this example, the genetics of
all the hens will be known by just their visual color. (Green ones are
XP+Y and Pallid ones are XpY) However, all the cocks will be
"possibles" as they are all Green but half are XP+XP+ and half are
XP+Xp.
All of the pairings and offspring for crosses involving only green and pallid traits can be viewed at the Pallid Tables page.
Combined Autosomal and Sex-Linked Trait Inheritance:
This is the most difficult 2 gene inheritance pattern to master.
(and the most involved we'll deal with in these pages) However, once
familiar with sex-linked inheritance, combining a sex-linked trait with
an autosomal trait to predict their combined inheritance is relatively
simple. It is no different in theory and practice than the last section
of the Autosomal Traits page (Multiple Gene Inheritance) in which the
combined blue and yellow sites were discussed. The only difference is
that a sex-linked trait (with it's superscript) is substituted for one
of the autosomal traits. We will examine the combined inheritance of
the autosomal blue trait and the sex-linked pallid trait. The notation
expressions for the possible parents are below.
B+B+
XP+XP+
|
= Green cock |
B+B+
XP+Y |
= Green hen |
B+b
XP+XP+ |
= Green/Blue cock
|
B+b
XP+Y |
= Green/Blue hen |
b b
XP+XP+ |
= Blue cock |
b b
XP+Y |
= Blue hen |
B+B+
XP+Xp |
= Green/Pallid cock |
|
|
B+B+
XpXp |
= Pallid cock |
B+B+
XpY | = Pallid hen |
B+b
XP+Xp |
= Green/Blue/Pallid cock |
|
|
b b
XP+Xp | = Blue/Pallid cock |
|
|
B+b
XpXp | = Pallid/Blue cock |
B+b
XpY | = Pallid/Blue hen |
b b
XpXp | = Pallid Blue cock | b b
XpY | = Pallid Blue hen |
Note that there are 9 possible cock gene combinations and only 6
possible hen combinations. This is because hens cannot be split for the
sex-linked pallid trait and, thus, cannot be Green/Pallid,
Green/Blue/Pallid or Blue/Pallid. We will start with a normal Green x
Green pairing to introduce the combined notation.
B+B+
XP+XP+
|
x
|
B+B+
XP+Y
|
=
|
Green cock cross Green hen
|
The cock can only contribute a B+ gene at the blue site (top) and a
XP+ gene at the sex-linked pallid site. (bottom) Therefore, the ONLY
combination he can give is this.
Similarly, the hen can only give a B+ gene at the blue site. But,
at the sex-linked pallid site, she can either pass on her XP+ gene to a
cock chick or the "geneless" Y chromosome (as a place keeper) to a hen
chick.
Filling these into a Punnett square, we would get the following:
|
B+
XP+
|
B+
Y
|
B+
XP+
|
B+B+
XP+XP+
|
B+B+
XP+Y
|
50 % of the offspring are Green cocks
50 % of the offspring are Green hens
Another way to represent offspring is in a table form. Such a table is
below with the offspring of this cross entered. The visual color of the
chicks are the columns and the split characteristics are entered in the
boxes.
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
US |
|
|
|
|
Hens |
US |
|
|
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
Just as when we were dealing with the blue and yellow sites together,
the blue and pallid pairs of genes are worked through the table
"independently" of each other once the possible contributions by the
cock and the hen are placed along the left and across the top of the
table. A more involved example is that of a Blue cock x Pallid hen.
b b
XP+XP+
|
x
|
B+B+
XpY
|
=
|
Blue cock cross Pallid hen
|
The cock can only contribute a b gene at the blue site and a XP+ gene at the pallid site.
The hen can only give a B+ gene at the blue site, but can provide either an Xp or a Y at the pallid site.
The resulting Punnett square looks like this.
|
B+
Xp
|
B+
Y
|
b
XP+
|
B+b
XP+Xp
|
B+b
XP+Y
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
DS |
|
|
|
|
Hens |
SB |
|
|
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
50 % of the offspring are Green/Blue/Pallid cocks
50 % of the offspring are Green/Blue hens
Though all chicks are Green, their genetics are known for certain once
they are sexed. Note again that all cock chicks inherit their mother's
single sex-linked gene and that the single sex-linked gene of all hen
chicks comes from their father. The results of the opposite pairing,
Pallid cock x Blue hen, is below.
B+B+
XpXp
|
x
|
b b
XP+Y
|
=
|
Pallid cock cross Blue hen
|
The cock must contribute a B+ gene at the blue site and a Xp gene at the pallid site.
The hen can only give a b gene at the blue site, but can provide either an XP+ or a Y at the pallid site.
Thus, the Punnett square looks similar, but gives different offspring.
|
b
XP+
|
b
Y
|
B+
XP
|
B+b
XP+Xp
|
B+b
XpY
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
DS |
|
|
|
|
Hens |
|
|
SB |
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
50 % of the offspring are Green/Blue/Pallid cocks
50 % of the offspring are Pallid/Blue hens
The cock offspring are the same as in the previous example. However,
the hen offspring are Pallid/Blue instead of Green/Blue even though one
parent is Blue and one parent is Pallid in both cases. This is because
(in this example) the father has the sex-linked pallid mutation instead
of the mother and, thus, he gives it to all his hen offspring. For this
reason, cocks with visual sex-linked traits (which have two copies) are
considered more valuable than visual hens (which have only one copy)
and are generally priced higher.
This example shows the power of knowing your genetics. All one would
have to do is look in the nest box and one would know, FOR SURE, that
all Pallid chicks were Pallid/Blue hens and all Green chicks were
Green/Blue/Pallid cocks. A Green/Blue x Pallid pairing yields a
slightly more complex result.
B+b
XP+XP+
|
x
|
B+B+
XpY
|
=
|
Green/Blue cock cross Pallid hen
|
The cock can contribute either a B+ or b gene at the blue site, but always gives a XP+ gene at the pallid site.
The hen can only give a B+ gene at the blue site, but can provide either an Xp or a Y at the pallid site.
The Punnett square is slightly larger, but still relatively straightforward.
|
B+
Xp
|
B+
Y
|
B+
XP+
|
B+B+
XP+Xp
|
B+B+
XP+Y
|
b
XP+
|
B+b
XP+Xp
|
B+b
XP+Y
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
SC, DS |
|
|
|
|
Hens |
US, SB |
|
|
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
25 % of the offspring are Green/Pallid cocks
25 % of the offspring are Green/Blue/Pallid cocks
25 % of the offspring are Green hens
25 % of the offspring are Green/Blue hens |
All offspring are Green and even after sexing, none of the genetics are
known for sure. All are "possibles". The results of the opposite
pairing, Pallid cock x Green/Blue hen, gives a similarly complex table
full of "possible" offspring.
B+B+
XpXp
|
x
|
B+b
XP+Y
|
=
|
Pallid cock cross Green/Blue hen
|
The cock can only contribute a B+ gene at the blue site and an Xp gene at the pallid site.
The hen can either give a B+ or b gene at the blue site and either an
XP+ or a Y at the pallid site. Her possible contributions are below.
B+
XP+
|
or
|
b
XP+
|
or
|
B+
Y
|
or
|
b
Y
|
The Punnett square is 1x4 instead of 2x2, but is still relatively straightforward.
|
B+
XP+
|
b
XP+
|
B+
Y
|
b
Y
|
B+
Xp
|
B+B+
XP+Xp
|
B+b
XP+Xp
|
B+B+
XpY
|
B+b
XpY
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
SC, DS |
|
|
|
|
Hens |
|
|
US, SB |
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
25 % of the offspring are Green/Pallid cocks
25 % of the offspring are Green/Blue/Pallid cocks
25 % of the offspring are Pallid hens
25 % of the offspring are Pallid/Blue hens |
The cock chicks are the same as in the previous example, but the hen
offspring are all visually Pallid. However, 100% of the chicks are
still "possibles". Therefore, it would be advantageous to avoid such a
cross unless necessary. As the degree of "splitness" increases, the
complexity of the table increases such as a Green/Blue x Pallid/Blue
pairing.
B+b
XP+XP+
|
x
|
B+b
XpY
|
=
|
Green/Blue cock cross Pallid/Blue hen
|
The cock can either contribute a B+ or b gene at the blue site, but can only give an XP+ gene at the pallid site.
The hen can either give a B+ or b gene at the blue site and either an Xp or a Y at the pallid site.
B+
XP
|
or
|
b
XP
|
or
|
B+
Y
|
or
|
b
Y
|
The Punnett square is now a larger 2x4 matrix.
|
B+
Xp
|
b
Xp
|
B+
Y
|
b
Y
|
B+
XP+
|
B+B+
XP+Xp
|
B+b
XP+Xp
|
B+B+
XP+Y
|
B+b
XP+Y |
b
XP+
|
B+b
XP+Xp
|
b b
XP+Xp
|
B+b
XP+Y
|
b b
XP+Y |
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
SC, DS, DS |
SC |
|
|
|
Hens |
US, SB, SB |
US |
|
|
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
With this pairing, there are 8 possible offspring. (2x4 table) Even if
there are duplicates, they are all brought down to the "offspring" table
to preserve the genetic ratios of the various chicks. Thus, each box
in the table represents 1/8th or 12.5 % of the whole. The results are
as follows:
12.5 % of the offspring are Green/Pallid cocks
25.0 % of the offspring are Green/Blue/Pallid cocks
12.5 % of the offspring are Blue/Pallid cocks
12.5 % of the offspring are Green hens
25.0 % of the offspring are Green/Blue hens
12.5 % of the offspring are Blue hens |
In this case, all the Green chicks are "possibles" and all the Blue
chicks are "known". Sometimes the results allow a certain visual color
of chick to always be "known" as in this case, and sometimes it is a
particular gender which is always "known" such as in a Green/Blue/Pallid
x Blue pairing.
B+b
XP+Xp
|
x
|
b b
XP+Y
|
=
|
Green/Blue/Pallid cock cross Blue hen
|
The cock can contribute either a B+ or b gene at the blue site and an XP+ or Xp gene at the pallid site.
B+
XP+
| or |
b
XP+
| or |
B+
XP
| or |
b
XP
|
The hen can only contribute a b gene at the blue site and either an XP+ or a Y at the pallid site.
The Punnett square is now a 4x2 rather than a 2x4 matrix.
|
b
XP+
|
b
Y
|
B+
XP+
|
B+b
XP+XP+
|
B+b
XP+Y
|
b
XP+
|
b b
XP+XP+
|
b b
XP+Y
|
B+
Xp
|
B+b
XP+Xp
|
B+b
XpY
|
b
Xp
|
b b
XP+Xp
|
b b
XpY
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
SB, DS |
US, SC |
|
|
|
Hens |
SB |
US |
SB |
US |
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
12.5 % of the offspring are Green/Blue cocks
12.5 % of the offspring are Green/Blue/Pallid cocks
12.5 % of the offspring are Blue cocks
12.5 % of the offspring are Blue/Pallid cocks
12.5 % of the offspring are Green/Blue hens
12.5 % of the offspring are Blue hens
12.5 % of the offspring are Pallid/Blue hens
12.5 % of the offspring are Pallid Blue hens |
All of the cocks are "possibles" and all of the hens are "known". Also,
we see our first Pallid Blue chick. You may have noticed already that
sex-linked (Pallid or Pallid Blue) hen chicks are easier to produce than
cocks as they only require one copy of the gene to be visual compared
to the cocks who need 2 copies for the trait to be visually expressed.
Again, this explains why sex-linked cocks are more valuable and more
expensive. One of the most complex of all tables to construct is a
Green/Blue/Pallid x Pallid/Blue pairing.
B+b
XP+Xp
|
x
|
B+b
XpY
|
=
|
Green/Blue/Pallid cock
cross Pallid/Blue hen
|
The cock can contribute either a B+ or b gene at the blue site and an XP+ or Xp gene at the pallid site.
B+
XP+
| or |
b
XP+
| or |
B+
XP
| or |
b
XP
|
Similarly, the hen can contribute either a B+ or b gene at the blue site and an Xp or a Y at the pallid site.
B+
XP
|
or
|
b
XP
|
or
|
B+
Y
|
or
|
b
Y
|
The Punnett square is now a huge 4x4 matrix.
|
B+
Xp
|
b
Xp
|
B+
Y
|
b
Y
|
B+
XP+
|
B+B+
XP+Xp
|
B+b
XP+Xp
|
B+B+
XP+Y
|
B+b
XP+Y
|
b
XP+
|
B+b
XP+Xp
|
bb
XP+Xp
|
B+b
XP+Y
|
bb
XP+Y
|
B+
Xp
|
B+B+
XpXp
|
B+b
XpXp
|
B+B+
XpY
|
B+b
XpY
|
b
Xp
|
B+b
XpXp
|
b b
XpXp
|
B+b
XpY
|
b b
XpY
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
SC, DS, DS |
SC |
US, SB, SB |
US |
|
Hens |
US, SB, SB |
US |
US, SB, SB |
US |
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
Now we see that there are 16 possible offspring from this 4x4 (= 16)
table. Each of these constitutes 6.25 % of the whole. The offspring
are as follows:
6.25 % of the offspring are Green/Pallid cocks
12.5 % of the offspring are Green/Blue/Pallid cocks
6.25 % of the offspring are Blue/Pallid cocks
6.25 % of the offspring are Pallid cocks
12.5 % of the offspring are Pallid/Blue cocks
6.25 % of the offspring are Pallid Blue cocks
6.25 % of the offspring are Green hens
12.5 % of the offspring are Green/Blue hens
6.25 % of the offspring are Blue hens
6.25 % of the offspring are Pallid hens
12.5 % of the offspring are Pallid/Blue hens
6.25 % of the offspring are Pallid Blue hens |
Though this cross will give the coveted Pallid Blue cock 6.25 % of the
time, 75 % of the offspring are possibles and only 25 % are known. If
one would instead choose a cock with a single extra blue gene
(Blue/Pallid instead of Green/Blue/Pallid) to pair with the hen in this
example, (Pallid/Blue) the resultant Punnett square is simpler and the
offspring are MUCH more desirable and 100 % known!
b b
XP+Xp
|
x
|
B+b
XpY
|
=
|
Blue/Pallid cock
cross Pallid/Blue hen
|
The cock can only contribute a b gene at the blue site, but can give an XP+ or Xp gene at the pallid site.
The hen, however, can contribute either a B+ or b gene at the blue site and an Xp or a Y at the pallid site.
B+
XP
|
or
|
b
XP
|
or
|
B+
Y
|
or
|
b
Y
|
The Punnett square is now a simpler 2x4 matrix.
|
B+
XP
|
b
XP
|
B+
Y
|
b
Y
|
b
XP+
|
B+b
XP+Xp
|
b b
XP+Xp
|
B+b
XP+Y
|
b b
XP+Y
|
b
XP
|
B+b
XPXp
|
b b
XPXp
|
B+b
XPY
|
b b
XPY
|
Results:
|
Offspring
|
Green
|
Blue | Pallid | Pallid Blue |
|
Cocks
|
DS |
SC |
SB |
US |
|
Hens |
SB |
US |
SB |
US |
KEY: US = unsplit, SB = split Blue, SC = split Pallid, DS = double split = split Blue and split Pallid
12.5 % of the offspring are Green/Blue/Pallid cocks
12.5 % of the offspring are Blue/Pallid cocks
12.5 % of the offspring are Pallid/Blue cocks
12.5 % of the offspring are Pallid Blue cocks
12.5 % of the offspring are Green/Blue hens
12.5 % of the offspring are Blue hens
12.5 % of the offspring are Pallid/Blue hens
12.5 % of the offspring are Pallid Blue hens |
A quick glance at the offspring table clearly shows that once the chicks
are sexed, ALL the genetics of the chicks are known just by their
visual color. In other words, there is only one entry in each box.
This is a fantastic pairing that requires no test breeding of the
offspring to determine genetics while producing a full 25 % Pallid Blue
chicks; half of which are the rare and powerful Pallid Blue cocks!
Pairings such as this are the goal of our breeding program.
All of the pairings and offspring for crosses involving the green, blue
and pallid traits can be viewed at the Pallid Blue Tables page.
By now you should . . .
- understand what sex chromosomes and sex-linked genes/traits are.
- be familiar with which Quaker mutations are inherited as sex-linked.
- know whether sex-linked Quaker traits are dominant or recessive.
- understand why hens only have one copy of sex-linked genes while cocks have two copies.
- realize that a hen CAN NEVER be split for a sex-linked trait and why that is.
- be familiar with the "X" and "Y" notation of sex chromosomes and how to represent a cock and a hen with them.
- be comfortable with notation such as XP+Xp and XpY.
- be able to set up a Punnett square of a Green/Pallid x
Pallid pairing and predict the genetics of their offspring. (try it !)
- be aware that cock and hen offspring of sex-linked crosses are necessarily of the same genetic make up or even color.
- know which parent is responsible for passing on a sex-linked trait to hen offspring.
- be comfortable with notation such as that below and be able to write out a description of each parent.
- be able to plug information into a Punnett square to determine offspring for a pairing such as this. (try it !)
- understand why a cock who is visual for a sex-linked trait
is more valuable and powerful than a hen visual for the same trait.
- understand the value of producing genetically "known"
offspring and use this knowledge along with genetics tables to set up
more efficient parental pairs.
If these concepts are not clear at this point, you may want to review this page again before going on.
Had enough? Go back to our Home Page and surf some other stuff.
Still thirsty for more? Peruse the 54 possible parental pairings involving the green, blue and pallid traits on the Genetics Tables pages and view all their potential offspring.
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