Polytomies can represent two different   cases. First, they can represent the literal hypothesis that a common   ancestral population split through cladogenesis (i.e., speciation) into multiple lineages. Under   this interpretation, such an internal node is referred to as a hard polytomy   (below left). Alternatively, someone who depicts a polytomy in a cladogram is   not really expecting that the same ancestor gave rise to all daughter taxa,   but is uncertain which resolved pattern is the best hypothesis. Under these   circumstances, such a node is referred to as a soft polytomy (below right).   This is actually the more common intended meaning of a polytomy.

多岐树可以表示两种不同的情况：一种是它们可以代表这样一个理论上的假设，即一个共同的祖先群体通过分枝进化（即物种形成）分裂成多个支系。基于这种解释下，这样的一个内部节点被称为硬多岐（左下）。另一种说法是，用分支图描述多分支的人并不是真的期望同一祖先产生所有子分类群，而是不确定哪一种解决模式是最好的假设。在这种情况下，这种结节被称为软多岐（右下）。这实际上是多岐的更普遍的本义。