MIMM 211 Lecture 3: MIMM 211 lec 3: classification / endosymbiotic theory
9 Sep 2016
School
Department
Course
Professor
Document Summary
We didn"t know the relationship between say, lions and roses. Hierarchical, species of groups had predictable features. Kingdom or domain phylum or division class order family genus species. Natural, evolutionary, uses dna comparisons to classify based on evolutionary relationships. No microbial fossils found, stromatolites are the closest we have. They are all similar in shape anyway, so taxonomic approach wouldn"t work. Therefore, ubiquitous (found in all species) gene sequence was used to compare mos and construct a phylogenetic tree. Different markers may produce different phylogenetic trees, so you need to use multiple markers to confirm an organism"s placement in the tree. 16s rrna gene has a fitting resolution to the level of kingdoms, but not really for genus/species. It doesn"t evolve fast enough to be different in different species of say, the same genus. Haeckel: 3 groups: plants animals protista (mos) Chatton: 2 groups based on whether the cells had nuclei: eukaryotes prokaryotes.
