Dimension space is called "fold in". When arriving at the destination, the act of leaving Super Dimension space is called a "defold" or a "fold out". Ancient astronauts The metaplot of the franchise is centered on a purportedly extinct humanoid alien race called the . It was first conceptualized during the pre-production of The Super Dimension Fortress Macross when the creators were researching cultural studies to develop concepts used in the plot. According to official sources, the Protoculture was the first advanced humanoid race in the universe—advanced Protoculture civilization started 500,000 years ago—and is the creator of the Zentradi and homo sapiens. Phases of colonization resulted in the establishment of an "Interstellar Republic", (similar to a galactic empire) which covers much of the Milky Way galaxy 2800 years after Protoculture civilization started (498,000 years ago). A civil war happened sixty years later, resulting in a split in the Republic. One of the factions' created "super-Zentradi" forces, which was later possessed by interdimensional beings—these forces are later called the "Protodeviln", which feeds on life energy of both Protoculture and Zentradi; some of both the Protoculture and Zentradi was later brainwashed into the "Supervision Army". The Supervision Army continued to battle both the Protoculture and Zentradi, which resulted in the dwindling of Protoculture population; they revoked the prime directive that banned Zentradi to attack the Supervision Army. This, however, made the war even more intense, and the Protoculture population sharply decreased; to avoid extinction, they seeded uninhabited planets by means of pantropy and avoided any conflict as much as possible. This action included the genetic engineering of homo sapiens on Earth by combining Protoculture genes with native genes; a "sub-Protoculture" race meant for preparing the Earth for a future Protoculture colonization. The genetic engineering crew, however, was immediately destroyed by anti-Interstellar Republic military ships. The final blow of the war happened because of the Protoculture lost control of the Zentradi; 475,000 years ago, the Protoculture was believed extinct. However it was discovered that 10,000 years ago, the Protoculture remnants made contact with humans in "Mayan Island", genetically re-engineering the native inhabitants to utilize the artifacts left by them. This included the "Bird Human" bio-mecha, tasked to destroy humanity if they are still in war. Other elements The franchise also explores minor themes including culture shock, capitalism, coming of age and nostalgia. The new era following the end of Space War I is