BSC 1011 Lecture Notes - Lecture 15: Cladistics, Synapomorphy, Paraphyly
23 Jun 2017
School
Department
Course
Professor
Document Summary
Envisioned that all species were descended from a single common ancestor. Length of a branch = length of time. Can help determine the order of branches for certain organisms. Used to infer the past and determine the order of ancestors. Similarity that is inherited from the most recent common ancestor of an entire group. Similarity that arose prior to the common ancestor of the group. A shared derived character that is shared by clade members. Presence of hair is a shared derived feature. Does not posses any of the derived characters. A species that is not a member of the group is designated as the outgroup. A group composed of an ancestor and its descendants. Defined by synapomorphy "hair": the tiger - gorilla human clade. A shared character state that has not been inherited from a common ancestor. Whales and penguins both have flippers but do not share a common ancestor.
