Halliday & Matthiessen (1999: 83-4):
Berlin (1972: 53) characterises the elaboration of labelled taxonomies as follows:Generic names are fundamental and will occur first. These will be followed by the major life-form names and specific names. At yet a later period, intermediate taxa and varietal taxa will be labelled. Finally the last category to be lexically designated ... of any ethnobotanical lexicon will be the unique beginner. The suggested sequence can be seen diagrammatically as follows:
... no temporal ordering is implied for some categories. Thus no claim is made as to the priority in time of specific names over major life form names. On the other band a claim is made that a language must have encoded at least one major life-form name and one specific name before the appearance of intermediate and varietal named taxa.