The Colonial Arms Race

Colonies competed with each other by developing specialized human cells that would give them an edge in a struggle for life. The eventual winner of the Colonial Arms Race was a sentient colony organized around hyper-specialized units, whose entire purpose was to direct the others. These colonies spread around the planet as they adapted the parts of their rivals to function within themselves. Thus were the modular people born. Living in fully industrialized megapolly, they came in the indescribable variation of shapes and sizes. Anything from castle-like guardian force to diminutive skull and core years was a member of the modular hole. They could combine with each other and split up or exchange parts as it needs presented itself