BI111 Lecture Notes - Lecture 16: Paraphyly, Convergent Evolution, Marchantiophyta
Document Summary
Bi111 week 5 phylogeny and plants. Twin goals of systematics reconstruction of evolutionary history and classification of species. Phylogenetic trees come about through successive events of speciation (branching), in which species gives rise to two (or more) Reconstructing these trees requires comparison of traits (with shared genetic ancestry) in multiple species: homologies are good, analogies are not (where similarities are not due to being related) Binary nomenclature genus and species (reflect the nested hierarchy of life) Taxon designation has 3 components: name what group does it belong to, rank where does it fit into the phylogeny, content relevant to species concept. All phylogenetic trees are guesses about how species are all related. Want to base phylogenetic trees on homologies not homoplasties. Another example is looking at the bone structures across many species: birds have really high ankles, but the basic structure is similar to other species.
