Consider the lilies, how they grow: they neither toil nor spin; and yet I say to you, even Solomon in all his glory was not arrayed like one of these.
(Luke 12:27) NKJV
The classification of plants animals and minerals is called taxonomy or systematics. Our scientific background is plant systematics. The modern age of systematics is based on comparing DNA sequences.
The history of the development of systematics is fascinating. The current system of grouping organisms into Kingdom, Phylum, Order, Class, Family and Genus dates back to Carl Linnaeus. Broadly speaking his system is still in place. The natural groupings of plants that he established using the naked eye to examine morphology, are confirmed by the use of DNA sequence analysis. What’s truly fascinating is that Linnaeus thought that he was discerning the systematic pattern in which God created the plants and animals.
Linnaeus developed his classification of the plant kingdom in an attempt to describe and understand the natural world as a reflection of the logic of God’s creation. His sexual system, where species with the same number of stamens were treated in the same group, was convenient but in his view artificial. Linnaeus believed in God’s creation, and that there were no deeper relationships to be expressed. He is frequently quoted to have said: “God created, Linnaeus organized” (Latin: Deus creavit, Linnaeus disposuit). The classification of animals was more natural. For instance, humans were for the first time placed together with other primates, as Anthropomorpha.
– Carolus Linnaeus (Wikipedia)
God created, Linnaeus organized. Spherogenetically.
In technical terms using DNA is an advantage over the use of the physical characteristics of plants to organize them because, supposedly, it eliminates personal bias. It’s conceivable that one scientist who’s organizing specimens based on the morphological structure of their flowers may derive a different classification system than someone else. The use of DNA eliminates the need for a human to subjectively evaluate characteristics, and so it should produce a phylogenetic tree of relationships which is natural: a reflection of what actually happened over time.
By studying DNA we should be able to see how the species which we observe today could be derived from a common ancestor. However, the classification system that we develop from DNA matches and merely increases the granularity of the original. The relationships were obvious without the need for DNA.