The branching points of the cladogram may be regarded either as an ancestral species (as in an evolutionary tree) or solely as representing shared characteristics.
When we are looking at a number of species and we want to place them in a cladogram, we assemble a dataset called a character matrix that contains lots of anatomical details of the species we are studying.
进化
，
两个
种间
都是由它们共有
-恐龙古生物
系统发育树或分支
望将它们放在分支
