Modern Evolutionary Classification

Evolutionary Classification Also known as Phylogenetic Systematics Basically means classifying organisms based on lines of evolutionary decent rather than just similarities and differences Phylogeny - the study of how living and extinct organisms are related to one another.

Common Ancestors Clades The larger a taxa is…the farther back in time all of its members shared a common ancestor Clades A group of species that includes a single common ancester and all the decendents of that ancestor Different from Linneaus’ taxa in that they must be a monophyletic group

Cladograms Diagram showing the evolutionary connections and common ancestors of species.

Derived Characters A trait that arose in the most recent common ancestro of a particular lineage and was passed along to its decendents Specialized shearing teeth, retractable claws…(Carnivora)…hair (for mammals)

Interpreting a Cladogram Nodes - points at which either common ancestors or derived characters occur on the cladogram Clade - single common ancestor and decendants Derived characters - written at nodes SEE PAGE 519

DNA in Classification DNA similarities are being used to create even more accurate cladograms based on evoltionary relationships and decent. Pandas and red pandas were reclassified into different clades based on DNA evidence