BIO 182 Chapter Notes - Chapter 23.1-23.3: Polyphyly, Paraphyly, Monophyly
Document Summary
Two evolutionary patterns: similarities among present species, historical patterns in fossils. Current species are evolved descendants of earlier species. Phylogeny study of the biological descent of species. Speciation populations diverge and are eventually unable to reproduce with one another thus creating a new specie. Node fork in the branch of the tree that represents the most common ancestor of the two branches. Phylogeny focuses on the evolutionary relationship between species while taxonomy focuses on the classification of populations. Phylogenetic tree representation of phylogenetic relationships. Phylogenetic trees can never truly represent evolutionary relationships because no one was around to physically observe the process of evolution throughout all of time. All living organisms come from a single common ancestor. More recently evolved species are not necessarily more advanced. Sister groups closest relatives are the only two species that share a certain common ancestor. Monophyletic a group including a single common ancestor and all of its descendants.
