The diorama in front of you is a recreation of the forests spread across Yambaru in northern Okinawa. It was painstakingly modeled to help park visitors locate flora and fauna.
As such, it also includes the Okinawan railbird. Its wings are olive-colored, with a belly streaked in black and white stripes, as well as a red bill. Can you manage to find it? Actually, the Okinawan railbird is officially designated as a protected species, as it is the only species of wild flightless birds in all of Japan. It is endemic only to the Yambaru forests.
The history of this rare bird is deeply intertwined with the birth of the Ryukyu Islands themselves. The land that would become the Okinawan Islands originally adjoined the Chinese continent and Kyushu. However, the two regions broke apart due to tectonic shifting, and the resultant changes in the ocean’s surface turned it into individual islands.
The stranded fauna evolved to suit their individual environments. Many believe that the Okinawan Rail Bird species retrogressed to where its wings lost the capacity for flight due to the lack of large carnivorous predators in its home region of Yambaru. Instead, it developed robust legs with which to catch bugs, earthworms, lizards, frogs, and other such prey.
Another theory exists, one more native to the islands themselves. Because the total area of the island is so small, there are few species capable of living there. In order to survive in such a limited space, the flora and fauna adapted to keep useful abilities and discard the unnecessary ones. One could say that the Okinawan railbird, flightless and yet adept at surviving overland, is a symbol of that evolution.
On the other hand, looking at the Ryukyu Islands as a whole, they are a treasure trove of endemic species. Unlike other islands that merely rose from the sea, the Ryukyu Islands once adjoined mainland China before breaking away, thus their wide biodiversity has been there from the start. That wildlife then adapted to the Islands’ separate environments, further splitting off into different species.
The dioramas of the forests of Yambaru and the Iriomote and Miyako Islands at the Museum are but a sample of Ryukyu’s peculiar ecosystem--to say nothing of how it changes from night today! We want you to feast your eyes on these exquisite dioramas, and then see the real thing for yourself.