Reproduction
Transformers have been shown to reproduce in a number of ways.
Some are built from scratch and when finished and turned on just spring to life (G1 Catoon Dinobots and Technobots).
In other stories they must be infused with life from an outside source. In the G1 Cartoon this was Vector Sigma, in the Marvel Comic it was the Creation Matrix.
The Transformers: Generation 2 comic introduced the concept of "budding" where it was revealed early Transformerss reproduced asexually until they reached the population Primus desired. At this turning point, the practice stopped and all memory of it was erased. When the Cybertronian Empire rediscovered and revived the process the successive generations of robots were increasingly less sentient and the lifeform called The Swarm was created as a byproduct.
Despite having two genders there is little canonical evidence for TFs reproducing sexually. The best case could probably be made for Beast Wars where Rattrap makes numerous off-color remarks that hint in this direction, especially directed at Silverbolt and Blackarachnia. It is unknown what effect the Beast Machines reformating of Transformers into Technorganic beings has on their reproductive options.
One confusing aspect of this apparent lack of sexual reproduction is the canonical use of genealogical terminology to describe certain relationships. The most common of these is when two transformers regard each other as "brothers" (e.g. G1 Sideswipe and Sunstreaker, or RID Optimus Prime and Ultra Magnus). However, the "Beast Era" widened the issue of reproduction when Rattrap referring to his "great-aunt" Arcee and in general the practice in Beast Wars/Machines of Maximals and Predacons referring to the Autobots and Decepticons as their respective "ancestors", as well as themselves as being their "descendents", implying a direct genetic (for want of a better term) lineage. Various sources of debatable canonicity suggest that Optimus Primal is specifically descended from Optimus Prime, usually through the phrase "his ancestor Optimus Prime". In the absence of sexual reproduction and nuclear families, the use and meaning of these genealogical references is difficult to explain.
