BIO 263 Lecture Notes - Lecture 6: Symplesiomorphy, Synapomorphy, Polyphyly
Document Summary
Monophyletic group an ancestral population and all descendants. Synapomorphy are traits unique to a monophyletic. Group that includes the common ancestor and also includes all of its descendants. Due to convergent evolution which seem similar but are not necessarily closely related to each other. Unnatural group that does not group of ancestors. Group that includes ancestral group and some descendants but not all descendants. Homoplasy because the traits are not from the common ancestor and evolved to look similar primarily due to similar pressure factors. Trait that certain groups have that exists in no other groups. Shared by group in state but also occurs elsewhere in the phylogenies. All symplesiomorphies are homologous traits along with synapomorphy. Trait certain groups have that also exists in the ancestor. Uniquely derived trait just specific to one taxon. Example would be species that are unique to simply one taxon. Synapomorphy of a single species is an autapomorphy. Homology should be more common than homoplasy.
