I am considering a human-like species that has a consciously controlled womb- like organ. These beings would be able to gestate and give birth to any smallish creature that fitted their purpose. Naturally, matter doesn't appear out of nowhere; they have to ingest enough food in order to do this. The creatures they create might not be able to breed, or lack other features. This skill would need practice, and these beings would produce specially designed warriors, livestock, or other animals this way instead of breeding them. They could give birth to them in the form of young to minimize energy requirements. The system could also be used to directly create objects they required out of bone, skin, or fur. The system could even still function as a womb and allow them control over the bodily form of their babies.
In short is it possible for a creature to have a sort of all-purpose bio-fabricator, how might it come about and how would it be used? The closest real example I can think of is a queen bee producing worker bees. However, the worker bees are relatively similar in form to the queen, and the queen can't consciously alter the design. This is my first question.
EDIT: This organ would work like a womb producing a baby except that the muscle, bone, skin getting placed/grown would be a conscious decision, not a biologically hard coded one.
So the person would be able to create a small "helper" creature which could find food or warn of danger, would obey simple instructions from the parent and would have a body plan suited to helping the person survive. Such "helper" organisms already exist, (bees) but their body plan is biologically hard coded.
EDIT 2: Any talk of how this could be exist mention DNA editing capabilities. What if the system involved sacks of skin, muscle and bone cells in solution. A coagulating agent, and a trunk like appendage capable of squirting them out, in a manner similar to 3D bioprinters. This method doesn't need DNA to be designed, and all the control is muscular. it also doesn't need any cells to grow, so could be very fast.