Trees: SpeciesIn Science, the tree is a part of Botany. The Tree is one of the key elements of symbolism throughout the world. Just as the spine (shushumna) trachea of the human body has energy levels, trees are thought to have energy levels. The three columns of the human body, which become the two/three pillars in architecture are linked to three trees: Life, Knowledge and Wisdom. At larger scales the tree is great rivers such as the Ganges or the Nile and ultimately the World Tree in the form of the Milky Way. Symbolically this is linked with the Tree of Life and World Tree. Trees thus become a link between microsom and macrocosm. Number symbolism is important in trees, especially 2, 3, 7, 8, 9, 12. Trees which are favoured vary in different religions and in different countries, determined in part by relaities of different climates.