The Irken race is unable to reproduce and does so now sejak cloning. It is unknown how they reproduce
d before they learned the cloning process, but it is possible that the first Irkens were born from a Queen due to their similarity to insects. The Control Brains are the ones who create the Irken babies, known as Smeets, and program their personality and all Irken knowledge into their PAK, which is attached to each Irken's spine to birth them, as seen in the episode Parent Teacher Night. The Control Brains are extremely powerful, even the two Irken leaders, the Almighty Tallest, must obey them, which makes the Almighty Tallest lebih like figureheads than actual leaders.


Zim, an Irken Defective, has caused many accidents in Irken history, many of which are covered in the cancelled episode The Trial. A few minit after his birth, he jammed up a chute with another Smeet that created a blackout on Irk, lasting for five years, which became known as "Horrible Painful Overload Day".Later, he and Invader Skoodge were involved in an accident with a security robot, which caused another blackout, this one lasting for four years. This event became known as "Horrible Painful Overload hari Part II".Tallest Miyuki sent Zim to work as a scientist on Vort Research Station 9, where he created an energy absorbing blob that devoured Miyuki. Her successor, Tallest Spork, was devoured sejak the blob when it returned to get its kolar after one hari of ruling. Tallests Red and Purple took power some time after this.Zim was also responsible for ruining Tak's life, when he plunged half the Irken military training planet Devastis into darkness, trapping her in her testing room. The Testing continued on the other half of the planet. When Tak escaped from her room, she pleaded with the Control Brain to let her take her test again, but she berkata she had to wait another 70 years, and was placed on a janitorial squad on planet Dirt.Zim destroyed Operation Impending Doom I sejak rampaging across Irk, believing it to be an enemy planet, almost destroying the Irken civilization. For this, he was sentenced to work on the Irken snacking planet Foodcourtia for all eternity as punishment for ruining Operation Impending Doom I.Zim is apparently proud of the disasters he has caused in his life, as revealed in the episode The Frycook What Came from All that Space.