A tree consists of two types of 'nodes':
-
tips or terminal nodes: species
connected to exactly one father
-
inner nodes: hypothetical ancestors
connected to one father
(and in the binary case to two children).
A group_name may be assigned to an inner node; in this
case, the node and all its children become a group.
<ARB_NT/INFO_MODE/M>
There are significant differences between
phylogenetic trees and binary trees:
phylogenetic trees binary trees:
------------------------------------------------------------------------
unrooted rooted
inner nodes have n children all inner nodes have two children
Since binary trees are much easier to handle, ARB converts
phylogenetic trees to binary trees.
|