I believe that, in G1 / Beast Wars continuity, the Cybertronians upgraded from completely mechanical bodies to nanobot-based technology, which is more efficient, but requires smaller physical forms for said efficiency. Protoforms are the nanobots waiting to be formatted into a specific body plan to match survival and disguise requirements of the planet to be explored. This also explains the Transmetal and Transmetal II incidents being referred to as upgrades. This is not the same as technorganic! Nanobots are synthetic life, miniature robots with very limited intelligence performing the tasks that cells do in carbon-based bio-life (squishies). --75.161.84.72 06:42, 31 January 2008 (UTC)

Well, according to Generation 2, Transformers were already nanobot technology. This biological quirk is why the Swarm existed and later the Vok. --ItsWalky 07:43, 31 January 2008 (UTC)