Two scientist produce two different cladograms for the same groups of organisms.

It is believed that all organisms derived from a common ancestor, and a cladogram shows the characteristics that the organisms have acquired or lost (evolutionary relationships) throughout time that gave rise to different species.


Comparisons of the similarities and differences between DNA in two groups serves to establish homologous relationships. Further, since DNA comes from an animal's ancestors, we can begin to establish the ancestral relationships of these animals.


Typological defines organisms based on physical similarities while phylogenetic defines them in terms of populations and ancestry.