Half-sider budgies are the rarest budgie variety all over the world.
Half-sider budgies are not a mutation, but they have a rare condition called tetragametic chimerism that causes the rarest color and type variation in budgies.
Tetragametic chimerism occurs in many living beings, such as butterflies, roses, cats, and humans.
![Half-sider budgies](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-1649762833.jpg)
![Half-sider budgies](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-1649762094.png)
![Half-sider budgies](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-1649762089.jpg)
How half-sider budgie occurs?
There is a half-sider budgie due to a known condition called the “tetragametic chimera.” A half-sider budgie occurs when two (or more) fertilized embryos (two zygotes) come together and create a chimeric embryo in the early stages of development, such as between 2 and 64 cells.
Between 2-cell and 64-cell development, the two embryos fuse with their DNA and become like a single embryo. The single budgie embryo continues to grow and become a healthy budgie.
A half-sider budgie is also called a chimeric budgie.
![Half-sider budgies](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-1649765099.jpg)
How to produce a half-sider budgie?
A half-sider budgie occurs in particular conditions that randomly happen.
To produce a half-sider budgie, scientists must interfere with embryos during their early stages of development. It is not possible to have a half-sider budgie without a science laboratory.
What is tetragametic chimerism?
Tetragametic chimerism is a rare form of chimerism that is congenital. Plants and wild animals can also have tetragametic chimerism.
Are half-sider budgies bilateral gynandromorph?
Bilateral gynandromorphism means a being has both male and female characteristics with bilateral symmetry.
A half-sider budgie may be a bilateral gynandromorph, asymmetric gynandromorph, or tetragametic chimera.
Half-sider budgie photos & videos
Half-sider budgie photos
![Half-sider budgies [+WITH EXAMPLES]](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-with-examples-1649774427.jpg)
![Half-sider budgies](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-1649762838.jpg)
![Half-sider budgies [+WITH EXAMPLES]](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-with-examples-1649774748.jpg)
![Half-sider budgies [+WITH EXAMPLES]](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-with-examples-1649774761.jpg)
![Half-sider budgies [+WITH EXAMPLES]](https://www.petiska.com/wp-content/uploads/2022/04/half-sider-budgies-with-examples-1649774755.jpg)
Half-sider budgie example video 1: A half-sider budgie “TWINZY”
Half-sider budgie example video 2
Is a half-sider but same color budgie possible?
Yes, a half-sider budgie may occur with embryos with the same colors and different DNAs. In this kind of condition, it is hard to understand whether a budgie is a half-sider or not.
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