Cage of Eden/WMG
The Entire island is the remanants of an attempt at Resurrecting a living person
- The entire island is populated by clones of extinct animals, or their descendents, who were created in an attempt to perfect either cloning or resurrection for the purpose of bringing Miina Isurugi back to life. But it didn't work. So they put a "Grave Marker" there as a tribute to her and abandoned it. ages ago.
They traveled forward in time.
- Miina's grandfather created the island and all the animals as a gift/memorial to his lost granddaughter. The island is man-made and created there on the last known location of the plane that was carrying her. All the animals were animals that she had drawn in the past.
Yarai's father helped create the research facility
- According to Kurusu-sensei, Yarai's father works at a foreign corporation. We know that the research facility was funded by several different corporations.