BIOL 172 Chapter Notes - Chapter 26: Molecular Clock, Maximum Likelihood Estimation, Ingroups And Outgroups
Document Summary
The placement of species into orders, classes, and so on, does not necessarily reflect evolutionary history. The first part of a binomial is the name of the genus to which the species belongs. Represents a hypothesis about evolutionary relationships regardless of how groups are named. Relationships are often depicted as a series of dichotomies, 2-way branch pts. Signifies that evolutionary relationships among taxa are not yet clear. Although closely related organisms often resemble one another due to their common ancestry, they may not if their lineages have evolved @ different rates or faced very different environmental conditions. Generally, unless given specific information about what the branch lengths in a phylogenetic tree mean for example, that they are proportional to time we should interpret the diagram solely in terms of patterns of descent. No assumptions should be made about when particular species evolved or how.
