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In this paper, we focus on the “why” of tree iconography. The recognition of time would eventually lead to the recognition of evolution as a fact of nature, and subsequently, tree iconographies would come to represent exclusively the evolutionary descent of species.
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These scala naturae would fuse with genealogical, pedigree thinking, and the trees that were the result of this blend would, from the nineteenth century onward, also include the element of time. It lies at the foundation of the famous “scala naturae,” as well as religious and secular genealogical thinking, especially in regard to divine, familial (kinship), and linguistic pedigrees that were often depicted by tree images.
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This philosophical idea would begin a fascinating journey throughout Western European history. It will be demonstrated that tree diagrams as we know them are the outgrowth of ancient philosophical attempts to find the “true order” of the world, and to map the world “as it is” (ontologically), according to its true essence. In this paper, we trace the historical roots and cultural meanings of these tree diagrams. Moreover, historically, tree diagrams themselves can be grouped into a larger class of diagrams that were drawn to depict natural and/or divine order in the world. Secondly, even before Darwin, tree diagrams were used by a variety of philosophical, religious, and secular scholars to depict phenomena such as “logical relationships,” “affiliations,” “genealogical descent,” “affinity,” and “historical relatedness” between the elements portrayed on the tree. Firstly, Darwin never called his diagram of common descent a tree.
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However, as is the case with most popular beliefs, this one also does not hold true. It is a popularly held view that Darwin was the first author to draw a phylogenetic tree diagram.
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