ANT 131 Chapter Notes - Chapter 5: Evolutionary Taxonomy, Ecological Niche, Phylogenetic Tree
Document Summary
Taxonomy | organisms are classified by physical similarities that reflect evolutionary descent. Homologies: structures shared by species on basis of descent from common ancestor. Basic genetic regulatory mechanisms are highly conserved in animals maintained relatively unchanged: ex. Analogies: similarities based on independent functional adaptation, not on evolutionary descent: developed from process = homoplasy, ex. 2 major approaches/schools to interpreting evolutionary relationships: evolutionary systematics, cladistics. Interested in tracing evolutionary relationships and constructing classification based on these. Recognize that organisms must be compared using characters (characters differ in importance) More rigorously defines the kinds of homologies that yield the most useful info. Ancestral/primitive: characters derived from remote ancestor: character seen in two organisms is inherited in both from a distant ancestor doesn"t provide enough info, ex. Derived/modified: characters modified from ancestral condition: ex. Shared derived: character traits shared in common between 2 life-forms links them. Clade lineages that share a common ancestor (group = common ancestor + all descendants: uses derived/modified characters.
