BIO260H1 Lecture Notes - Lecture 20: Radial Tree, Epistasis, Asso
Document Summary
Determine relatedness from distance back in time to mrca: rooted tree. Provides orientation or polarity for the tree. Inclusion of one or more sequences that are known to lie outside the diversity of the sequence of interest. Arbitrarily presenting the tree so that lineages are balanced. Qualitative statement about evolutionary relationships: homoplasy similarity not due to common ancestry, species phylogenies. Typically - genetic variation xed between species. Many types of data: gene genealogies (gene trees) Evolutionary history of alleles at a single gene. Typically - genetic variation within a species. There can be tremendous diversity among the evolutionary histories of individual genes within a species. Gene genealogies have the potential to di er from the species phylogenies in which they are embedded. The evolutionary histories of individual genes are re ected in the genetic variation found within populations. 1. 2 molecular population genetics: classical population genetics how do evolutionary forces a ect future change in allele and genotype frequencies, coalescent theory.
