BISC 120Lg Lecture Notes - Lecture 5: Motoo Kimura, Silent Mutation, Gram Staining
Document Summary
Bisc 120: general biology: organismal and evolutionary biology- lecture 5: Phylogenetic trees, structure and function of prokaryotes, and prokaryotes and genetic. Group species into clades (ancestor and all its descendants) Who is the same and who is different. What takes the least amount of changes. Fewest changes is most likely because it has the highest probability. Example is how birds and mammals independently developed four- chambered heart. Also an example of convergent evolution or homoplasy. Its an alternative approach to reconstructing phylogeny. The best tree is the tree that displays evolutionary facts but also takes into account the changes of dna due to mutations etc . We can determine which trees are more likely because dna tends to mutate at a constant rate over time! Even when mutations occur, we have homologous sequences because they have sections that are the same because of their common ancestor; even though it is being expressed differently.
