The adventure of the zebrafinch white cheeks
First and foremost, I would like to thank the people I have worked with on the evolution of white cheek zebra finches over the past few years.
This text therefore not only tells about my experiences but also their experiences. Thanks to Paul Chabot, Jan Van Looy and Wessel Vermeulen. When I use the term "I" later, you must understand "we". We do not agree on all the details. Fortunately, because then we can discuss it. And we continue to encourage each other on the results to improve and the conclusions to be made.
At our zebra finches, everyone knows the cheeks and the black cheeks. In these two mutations, both males and females have colored cheeks. We now also have the white cheeks. So we have white, brown and black cheeks.
The first time a white-cheeked zebra finch appeared was when Jacques Vanduren wondered if he had bred a new mutation. Some of its birds could be admired in the exhibitions of the B.Z.C. (Belgian Zebrafinch Club).
Jacques also wrote an article on this subject in our magazine, illustrated with photos of details. It was the end of the 90s of the previous century. Jacques was unlucky enough to lose his breeding and eventually the white cheek zebra finch disappeared. However, he had even given birds to other hobbyists in order to avoid the risk of extinction. But these other amateurs couldn't build a strain. Result: the white cheeks are returned to square one.
A few years ago, the founding president of B.Z.C., Paul Chabot, discovered a "special" zebra finch. Paul Chabot is the one who, in his time, took the first steps with a male of the orange breast mutation. So he had experience building a "special" strain.
This bird also had black in its cheeks, which is why Paul went in search of a black-cheeked partner for this zebra finch. His mindfulness was good for the white cheeks. For he directly raised white cheeks !
That's why he decided the white cheek factor was dominant. But Paul also used other zebra finches besides the gray black cheeks. When Jan and I went to interview Paul, we saw White Cheeks combined with masked, Black Chest Mutation and even crested. Paul explained to us that he had had many deaths among his birds, he knew of Jacques's experience and he was betting on a lethal factor in white cheeks.
Paul gave each of us a zebra finch because he was afraid the next breeding season would be disastrous. His secret hope was that we would help him. Then it turned out that the health of his birds was the cause of his growing problems. So we were able to eliminate the lethal factor from our reasoning.
In Dordrecht Paul met Wessel Vermeulen who also had zebra finches with partially white cheeks. Wessel even bred zebra finches having three colors in the cheeks. They show white (the tear line is absent), then comes black and normal brown in the posterior arch of the cheeks.
In the meantime Jan and I have started breeding with our white cheeks. Our goal was to understand the inheritance of white cheeks.
When Jan and I started breeding many told us they thought it was a combination. Some thought of the black chest mutation, others of the black chest black cheek jumpsuit. Several had already seen traces of white cheeks. And indeed, we did not speak of white cheeks only with us. The internet, as we know, makes contacts all over the world. I know that in other countries we talk about white cheeks: Israel, Italy, France.
Let's take a more in-depth look at the white cheeks. What is important: we make a distinction between combinations of white cheeks with black cheeks and those without black cheeks. This distinction will be the common thread of this story.
3. Is this a new mutation?
I can only give you the opinion of the above breeders: this is a mutation. So, a resounding and unanimous YES !
All of our experiences and results point in this direction with a yes. What is not yet fully defined is what this mutation will ultimately be. But so were other changes in the world of zebra finches.
When it comes to breeding, we focused on building a base on which we could put in place targeted controls. In a normal mutation, such as black breast, orange breast, white breast, etc., carriers are raised and they are crossed with the parents in order to return to the original mutation.
In white cheeks, the hereditary rules are not yet known. So the goal was to raise as many youngsters as possible and to make as many matings as possible. This is to find out if the mutation was recessive, dominant or sex-related or autosomal, coupled with another known factor or not. The aim was also to know how the characteristics and possibly the characteristics of carriers are transmitted. We also had to make sure we didn't lose the white cheek factor in case it was a recessive factor. And we raised carriers. In order to maximize the interpretation of the results (read young people). I raised the same year with youngsters from the first round. The consequence is that we have been able to have a solid base with several breeders and we can already draw conclusions. Jan, Wessel and I are convinced that the white cheek mutation is recessive, Paul remains convinced that it is dominant over the black cheek. We will explain this in another way later.
The point on which we have had the most discussions is the aspect of mutation.
And it makes sense: the focus has been on how the mutation works, not how it "looks". Therefore, I repeat: this account shows the results known to date. And we are convinced that the white cheeks are still going through a major evolution. I also repeat that we should be happy that Paul Chabot came up with the idea of immediately setting up matings with the black cheeks. Because he did not have enough black gray cheeks on hand, he used masked black cheeks, black chest, crested ... When interpreting the results, we had to take into account the influence of these factors. It is sometimes difficult to detect the features of white cheeks in suits.
Let’s come back to the interpretation of the results. Out of the 90 youngsters obtained, I have about 7 female white cheeks. I had a few pure white cheek females. Why no male? Not because as you might think this is a gender mutation, but because I am setting the bar very high for the end result. I wanted the male white cheeks, in combination with the black cheeks, to also present a completely white cheek with no black residue (curl) in the cheek. I considered them to be carriers.
Subsequently, by raising white cheeks without the black cheek factor, I changed my mind. I am now okay with leaving some black residue in my cheek. However, I still dream of a male with white cheeks - black cheeks with totally white cheeks. Breeding results indicate recessive inheritance. We will now see what the mutation causes.
In the past, the emphasis has been, as the name suggests, on the color of the cheek; this is not the only change. But the cheek modification is the modification that has just given the current name: “White Cheeks”. From here we make a distinction between white cheeks with or without black cheeks.
Change in a white cheeks which is also black cheeks: The tear line is missing in the male and in the female, the sides disappear, the sides are white in the male and the female. In the male, there is still some black, but it is minimal. This is not a drawing of white dots on a black background. The dots became vague just before the end of the small feathers. These waves, ripples, are found in the transverse direction. In males: the whiter the cheek, the whiter the flank.
Therefore, I think we can breed males with completely white cheeks and flanks. The cheek is white for both male and female. Keep in mind that for the moment in males a black arch remains on the back of the cheek.
The male's breast bar and striped pattern are also influenced. I am of the opinion that the welts continue towards the stomach and the chest bar sticks out, especially on the sides. That’s what I’m currently planning. Could this be a target for breeding? As well as the whiteness of the cheek? So I can say: the whiter the cheeks, the lighter the striped pattern. The wavy pattern of the flanks can be seen as a ramp towards the welts of the chest.
Besides that some things are not changed by the mutation: the pants remain white, the beak line remains present, the tail blocks remain intact and the color is not affected. This goes for all mutations combined with white cheeks. In my opinion, white cheeks will be associated with all existing mutations. Whether this gives a beautiful bird in all mutations is another matter.
Changes in white cheeks that are not black cheeks: The tear line is missing in both males and females. The enlarged parotid area is the same color as the belly. The design of the sides is changed to an already mentioned wave pattern or zebra pattern. In the female the flank has the same color as the belly. The color of the cheek is retained. The chest bar: here I noticed an increase in the zebra pattern as shown above. The natural characteristics remain unchanged here.
You can see that there is indeed still a lot of testing to be done. The white cheeks will go through a whole evolution before seeing its characteristics fixed.
But the black face has also experienced this evolution. And note that the black-face standard states that the chest bar must flow at least 15 mm. Look in our shows: with such a black face you no longer get any decent score.
I summarize: The combination of white cheeks with black cheeks makes the cheeks and flanks of both male and female white. Jacques Vanduren wrote that it was probably a mutation of drawings. I think he was right. The designs are the components that are affected by the mutation. Wessel bred males with some sort of hemmed pattern (wavy pattern) in the cheeks. The chest bar remains unchanged from normal.
Wessel asks the following question: is the white breast a white cheeks? The white breast has normal flanks with dots. The answer is therefore: NO!
Photo: White cheeks load-bearing gray black cheeks, note the vague ripple shape in the flanks
4. Ideal image of white cheeks
To do this we must distinguish white cheeks and white cheeks combined with the black cheeks.
The other mutations also change the standard if the mutation is combined with the dark cheeks. The combinations with the black cheeks are in my opinion white cheeks with fully white cheeks. The teardrop must be missing to create this complete image. We often have such females with full cheeks, no tears and completely white flanks.
There remains the question of the chest bar and the zebra pattern. The final verdict will bring the results. The ideal image without dark cheeks is "limited" to the disappearance of the teardrop and the presence of the wavy pattern of the flanks. The cheek and cheek color remain intact. The parotid area receives color from the belly. Here also remains the question of the chest bar and welts. Practice will show us in both cases where the border is. And practice will also ensure that the white cheeks become an addition in the range of mutations in our zebra finch.
Carriers in breeding tests I mentioned: partial white cheeks, white cheeks and normal. These are working tests to find out whether the mutation is dominant or not. The results showed that we are not really talking about a dominant factor. A white cheek mated to a normal or a black cheek didn't give the ratio of youngsters we were expecting with a dominant factor. White cheeks are actually spread in a recessive manner. What we can deduce from the combination with the black cheeks is that the white cheeks make the black of the flanks and cheeks disappear. The white cheeks counteract the expression of black. When we talk about a recessive factor, we automatically come to talk about carriers of this factor.
5. How to recognize them ? What can we deduce from our results ?
The white cheeks make the lines of tears disappear. In the flanks we see a wavy pattern. At the carriers, we can focus on the designs. An additional difficulty is that the white cheeks need eumelanin to stand out very clearly: the more the bird has eumelanin at the base, the more clearly its absence is noticed. The "split" characteristics also support this disappearance or partial disappearance of black in the drawings, and this is easier to detect in combination with the black cheeks.
So what do we see in black-cheeked and white-cheeked split ? For black cheek wearers we should look for an increase in black and in white cheek split the disappearance of black.
So, recognizing white-cheeked carriers is not easy. However, I think nature gave us a little push. Using birds that I have raised, I have tried to mate two split birds together. I discovered this: Some males have a wavy pattern in the flanks; this wavy design (zebra type) can even extend over the entire side. I described this design as a white stripe across the end of the nib. The white dots become small white waves. This form of ripple is present in both dark cheeks and normal ones. It is not the same design as in the black chest where the white dot is lying on the feather. These males are split of white cheeks.
This form of ripple is also found in the flanks of some females. As in the orange breasted female, this form is not clearly visible. This form of ripple is also found in gray females. These females are carriers of white cheeks.
In black cheeks (male and female) you see the cheek disappear. Usually, the disappearance begins on the side of the teardrop. The rest of the cheek can also be affected: lighter areas, thin dark lines on a light gray background. These are split.
I wonder about the teardrop. When I mated a black cheeked partner with a teardrop with a white cheek carrier bird, then I never bred white cheeks.
Photo: detail of the head of a male split white cheeks brown (bearer black chest)
Photos: bearer white cheeks in gray, brown and masked
Currently, split are more easily detected in males than in females. This is because we detect a change more quickly in a male. In a female, the cheek is where the split trait can best manifest itself, and most clearly in the parotid area. The “split” chapter is still an open book where we can experiment a lot.
The inheritance ... So far we now come to the hard part. I have already reported that breeding pure white cheeks is not that simple. It is true that the white cheeks are "helped" by the black cheeks. Without black cheeks, we wouldn't have bred white cheeks.
Let's imagine another simple way: The white cheeks removes all that is black in the cheeks and sides. This means that the white cheeks removes the tear line in normal and removes the flank and cheek marks in a black cheek. The belly color of the initial mutation replaces these missing marks. The white cheeks change the markings of the flanks into a wavy pattern.
From our breeding results we can conclude the following: Each pair of white cheeks with black cheeks or vice versa results in black cheeks and black cheeks bearing white cheeks. Matings of normals with white cheeks give normals. These zebra finches carry white cheeks. In some we see characteristics of wearer black cheeks (white cheeks that masks black cheeks).
The results of our matings show that the mutation is transmitted in an autosomal and recessive manner compared to the normal ones.
The results also show that white cheeks only work on eumelanin in cheek and flank designs. In black cheeks, it prevents the manifestation of black in the cheek. White cheeks are recessive and therefore the factor must be present twice to get white cheeks. The white cheeks alter the designs of the cheek and flank, removes the teardrop and creates a wavy pattern in the flanks.
The white cheeks have some influence on the chest bar, the tail blocks are not changed. We first raised white cheeks in the black cheek series. So we first thought that the white cheeks were hidden behind the black cheeks. What do we mean by this? Simply we said that the white cheeks only works in the dark of the cheeks and flanks. And this is true. Then it turned out that white cheeks can work in cheeks even if pheomelanin is changed to eumelanin. And in what mutation is this conversion completely finished? Indeed ! In the black cheeks.
When the cheek is not black the postman only removes the eye line (black).
To sum up: White cheeks is an inhibitor preventing eumelanin from appearing in certain parts of drawings, especially the teardrop, cheek and flank.
This factor is autosomal and recessive. Two parts of this sentence are important: inhibitor and eumelanin. We can imagine the white cheek factor to be a separate factor from the black cheek factor. It can be present in all varieties of zebra finch, but we see its effect best if the cheeks and sides are black. This explains that the male and female white cheeks are recognizable by looking at the designs. And this also explains that the wavy design in the sides disappears in combinations with black cheeks.
In a normal gray, the double factor white cheeks may be present. We see it act on the gray (black) by the disappearance of the teardrop and by the wavy design in the sides. The teardrop is indeed made up of eumelanin. The question then is: "can we call them White Cheeks?" We talk a lot about the factors associated with zebra finches. These have 9 pairs of chromosomes: 8 autosome pairs and 1 sex pair. But this is a bit simplistic. Science tells us that the zebra finch has as many pairs of chromosomes as a chicken. Science divides chromosomes into macro chromosomes, micro chromosomes and sex chromosomes. A zebra finch has 7 macro pairs, 32 micro pairs and 1 sex chromosome pair. There is therefore a great chance that two uncoupled factors are re-coupled.
Photos: male and female black cheeks split white cheeks
The white cheeks is an asset in the hobby on several levels: Combined with the black cheeks, you get zebra finches with white cheeks and sides: good as a novelty in the expos. Combined with normals, you get zebra finches with a beautiful wavy design in the flanks. The combination with other mutations is a great playground for experienced breeders. Breeders focusing on the standard can take inspiration from the evolution that the Black-face has gone through and bring the white cheek to classy birds.
We can say that the white cheeks represents a new unexplored chapter in our hobby.
Wessel birds keep tricolor cheeks. I believe this will be the next chapter in our zebra finch history.
I thank Paul, Jan and Wessel for their passion and involvement. We just spent one more year of experimenting. This year's results give us the impression that two factors lie at the base of white cheeks. The story does not yet come to an end.
Text and photos : Luk Lievrouw in cooperation with Paul Chabot, Jan Van Looy and Wessel Vermeulen.
Belgische Zebravinken Club