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How can a phylogenetic tree be rotated without changing its meaning?

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A diagram showing the tentative evolutionary relationships among hominid species over the past four million years, with skull images and labeled species names connected by solid and dotted lines to indicate proposed evolutionary pathways. — phylogeny Tentative phylogenetic scheme for the evolution of the human lineage. Solid bars indicate the time ranges during which species are thought to have existed, based on fossil evidence. Dotted lines signify evolutionary relationships between hominin species that have been proposed on the basis of the fossil evidence.

A phylogenetic tree represents the evolutionary history and ancestral relatedness of organisms through a branching diagram. Because these trees depict lines of descent rather than physical similarity, their visual orientation is flexible.123

You can rotate the branches around any node without changing the meaning of the phylogeny. The information contained in a tree is defined by its branching pattern and the relative positions of nodes and tips, not by the specific direction in which the branches point or their physical layout. Whether a tree is drawn with diagonal, rectangular, or circular branches, or is oriented in a different direction, the evolutionary relationships remain identical as long as the connections between the nodes and the descendants at the tips are preserved.32

When interpreting these diagrams, it is essential to trace the path from the nodes—which represent common ancestors—to the tips, rather than relying on the proximity of branches or the orientation of the tree.3