01415nas a2200217   4500000000100000008004100001653002500042653002900067653001800096653005500114653001700169653001700186653003200203653001900235100002100254245008600275300001000361490000700371520079900378022002001177                                       d10aArtistic inspiration10aBio-cultural interaction10aBio-diversity10aCo-extinction of cultural and biological phenomena10aConservation10aEphemerality10aIntangible Natural Heritage10aWorld heritage1 aMarcel Robischon00aGhost of the Forest: the Tangible and Intangible in Natural and Cultural Heritage  a20-300 v103 aUnderstanding the close interconnectedness of cultural and natural, tangible and intangible heritage is central to conservation efforts. This point is illustrated by examples in which works of culture have lost their original cultural or natural context - And this includes intangible natural phenomena. Further examples are given in which biological species survived as a genetic continuum but were changed in terms of their intangibles, i.e. their behaviour, in ways that can be perceived by human observers. In this article it is argued that the addition of a fourth category of  intangible natural heritage  to the existing categories of World Heritage would strengthen conservation efforts and bring forward the discussion with an integrated understanding of natural and cultural heritage.  a19753586 (ISSN)