If you took the city of Tokyo and turned it upside down and shook it you would be amazed at the animals that fall out: badgers, wolves, boa constrictors, crocodiles, ostriches, baboons, capybaras, wild boars, leopards, manatees, ruminants, in untold numbers. There is no doubt in my mind that that feral giraffes and feral hippos have been living in Tokyo for generations without seeing a soul.