What is interesting is that there is a another tree of life...this tree is not a manipulation or hijacking of the tree of life from the Bible.
This is Darwin's Tree of Life revealing biological life.
This was called a tree not because of the Bible, but because when one literally diagrams biological life one literally draws a tree.
This diagram could have taken any shape, but it does not.
A TREE shape then is very significant in understanding the PHYSICAL layer, but also the SPIRITUAL layer.