The real etymology is lost, I am afraid, but various speculations have been offered since antiquity and continue to this day. In Egypt the tree was known since at least 2600 BC. Egyptians already used the same name ('Bennu') for the bird and the date fruits. Bircher in The Date Palm A boon For Mankind speculates as to the reason:
"This bird was found on ...
My favorite one is the ancient Chinese classification of animals from the
Encyclopaedia of Benevolent Knowledge:
Unfortunately, the primary source did not survive
A hierarchic process of producing taxonomies was formalized by 3rd century AD logician Porphyry in his presentation of Aristotle's classification of categories, and became popular during middle ages in a diagrammatic form of "Porphyrian tree". One starts with the highest category in a field, "summum genus", and proceeds in successive steps by using "...
Linnean taxonomy was very much the progression and refinement of earlier taxonomic thoughts. This answer draws heavily from "Linnaeus as an Intermediary between Ancient and Modern Zoölogy; His Views on the Class Mammalia" by W. K. Gregory (1908).
Gregory notes several major figures in the history of taxonomic nomenclature before Linnaeus: