HONR 1033 Lecture Notes - Lecture 4: Convergent Evolution
Document Summary
Certain physical and chemical processes result in isotopic partitioning within substances (basically, one form is preferred over the other) These differences can be measured (i. e. ratios of one isotope to another. Group taxa based on shared novel morphology. Clades are the subunits-the lego pieces of the tree of life. All of the taxa (no more, and no less) that are descended from a recent common ancestor. Reconstructing should not be hard, for shared morphology means shared evolutionary history, so the more morphology taxa share, the more closely they should be related. Homoplasy: shared morphology not inherited from a recent common ancestor - why it"s not as easy to reconstruct clades. Refers to features shared by two taxa that were not present in their most recent common ancestor. Grade : a group of taxa that shares a suite of functionally adaptive features.
