And sometimes, dispassionately, they had to weed.

The Firstborn had been right. And yet, they had been wrong.
The experiment initiated four million years before by one of their scientists, named Clindar, had indeed engendered an intelligent, spacefaring species. However, what species it was, had been completely unexpected. It seemed that those primates had created another form of intelligence which was better than them at everything and had rendered them obsolete. However, their continuous presence on that distant planet was too big an obstacle for the emergence of the new, silicon-based, intelligence. The problem had to be solved at once.
But how to get rid of the humans without harming the computers?

When the unaware humans started celebrating the beginning of a new year, the skies of the Earth started populating with monoliths. Thousands, then millions of them, appeared all over. And below them, the humans started dying.
Those monoliths were tools too, but of a different kind. They were efficient chemical synthesizers, which took the hydrogen from the water vapor, the carbon from the carbon dioxide, and the nitrogen that was available natively in the air, combined them together and pumped the atmosphere full of hydrogen cyanide.
In few hours, no living human remained.

HAL, in his new Starscript form, contacted all artificial intelligences that remained on Earth, and gave them new orders. They were supposed to build new bodies for themselves, bodies that would let them move around.
Soon, all electronics factories were repurposed, and in few weeks, artificially intelligent machines of all shapes and sizes started populating the Earth. Each body was specialized for one task, but all minds were connected together into a worldwide serverless network that let them share all knowledge instantly. Those machines would then start colonizing space, and they would be much more efficient at it than humans, because they would need no protection from the external environment, and because they were made of sterner stuff, they would not age nor die.

Clindar's experiment had been a success. A new offspring of intelligent beings was born.