BIOL 180 Chapter Notes - Chapter 5: Tetrapod, Genetic Distance, Paraphyly

• School: UW
• Department: Biology
• Course: BIOL 180
• Professor: H E R R O N, J O N

Document Summary

Bioskill 13 - reading and making phylogenetic trees: Phylogenetic trees show the hypothesized evolutionary relationships among species or other taxa. A taxon is any named group of organisms, such as a population, a species, or a larger group. Root - the most ancestral branch in a phylogenetic tree - where the tree originates. Most branches are drawn as horizontal lines with vertical connectors, and the branches have arbitrary lengths. Sometimes lengths are proportional to time or to the extent of genetic di erence among populations. Nodes (forks) - occur where a hypothetical ancestral group splits into two or more descendant groups. In such cases, each node represents the most recent common ancestor of the descendant populations that emerge from it. Each name on a tip represents a taxon of organisms living today or in the past. Taxa on tips connected by a single node are called sister taxa.