Although both are named DM jade, you must know that DM in Fischeri means "Dominant" based on the person who first discovered it. Meanwhile, the DM in Roseicollis discussed in this article is "Dimorphic."
Agapornis Roseicollis, phenotypically male and female, have no distinction in physical appearance because they are Monomorphic species.
Mono means "one', and morphic means in a particular form or shape. Therefore, monomorphic, in this case, means a sex or gender that is similar in size and appearance.
This is what makes lovebird breeding a challenging hobby. Unlike in other species, such as the budgerigar, there is a specific way to tell if it is male or female by the color of the nose or cere.
But in lovebirds, it is tough to determine the sex. Even experienced breeders claim they have almost 90% to 100% accuracy in sex determination. It is just a prediction. The sure thing is that when lovebirds have laid eggs, they are females.
Finally catching up with technology, DNA sex testing has become available, and many lovebird breeders are utilizing this genetic tool as it has proven to be very helpful and highly accurate.
So, just by plucking a feather or with a blood sample for DNA Sexing, it can be known which is male and female so they can use it in mutation projects, or they can sell these chicks and accurately claim whether the chick is male or female.
But why bother with the extra difficulty and expense of sexing lovebirds when there is a charming and beautiful color mutation that, for the first time in the history of Agapornis, determines which one is male and which one is female just by the different variations in the color of its feathers.
Let me introduce characteristic DM jade or dimorphic jade Roseicollis.
Unlike the other lovebirds that are sexual monomorphism where we cannot visually identify which one is a hen or a rooster without the need for DNA Sexing methods, this mutation in roseicollis is what we can call sexual dimorphism; hence, the name DM jade or dimorphic jade.
Sexual dimorphism or dimorphism is a condition in which two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs. In the case of DM Jade Roseicollis, the difference is in the intensity of the coat color.
DM jade was first discovered in the aviary of a breeder in Trieste, Italy, named Miriam Bisiacchi. Jade's appearance, similar to the Marble Mutation, meant the bird was not immediately identified. At the time, who would have thought that a new color mutation would emerge that would be dimorphic?
The first thing he did was to pair it with *blue* x blue/marble jade. Then, blue jade x blue marble and blue jade x pale blue. Then he paired the jade with green jade and got a split. The DM jade inherited an autosomal recessive. He then paired blue jade with green jade. Then jade x green/jade/blue.
The journey to pleasant surprises did not stop there, as over the next few months, Miriam was able to notice unusual traits in these birds. She seemed to observe distinguishing marks in the plumage between males and females.
Firstly, the overall plumage of these birds showed a slight reduction in eumelanin, resulting in a light yellow plumage when green and an incredible jade-like color when turquoise. Then, something caught Miriam's attention: the bellies or abdomens of the female birds were much lighter than the males. Then she also noticed that tmale'se's flight feathers were slightly darker than tfemale'se's and without fringes, while tfemale'se's flight feathers were lighter and showed fringes or edges.
In 2015, Miriam sent some feather samples to Ornitho-Genetics VZW MUTAVI, a research and consultancy group headed by Dirk Van den Abeele; the rest is history. Below are images showing the dimorphic characteristics of the exquisite DM jade bird.