Norfolk boobook mated with the female with the pair producing fledged chicks in 1989 and 1990. The original female disappeared in 1996 but, by then, there was a small hybrid population of about a dozen birds. These birds and their descendants continue to exist on the island. Norfolk boobook The Norfolk boobook ("Ninox novaeseelandiae undulata"), also known as the Norfolk Island boobook, Norfolk Island owl or Norfolk Island morepork, was a bird in the true owl family endemic to Norfolk Island, an Australian territory in the Tasman Sea between Australia and New Zealand. It is an extinct subspecies of the morepork ("Ninox
Failure to refer Failure to refer Failure to refer, also reference failure or failure of reference, is the concept that names can fail to name a real object. According to Bertrand Russell's theory of truth, there is only one actual world, and a statement's truth value depends on whether the statement obtains in the actual world. Continuing the tradition of Gottlob Frege, Bertrand Russell posited that a name picks out, or refers to, a real object in the world (Russell's correspondence theory of truth). The name "Genghis Khan" thus picks out the 12th and 13th century Mongol leader we know by that name.