BIOL 2325 Lecture Notes - Lecture 1: Paraphyly, Synapomorphy, Formal System
Document Summary
Taxonomy is a formal system for naming and classifying species. Systematics studies variation among species to reveal evolutionary relationships. Groups defined by share a common characteristic characteristics of common descent. Typological species concept- species are defined by fixed, essential features. Biological species concept-a reproductively isolated population that occupies a specific ecological niche(an organisms role in it"s ecological community) Evolutionary species concept- a single lineage of ancestor-dependant populations that maintains its identity from other such lineages and that has its own evolutionary tendencies and historical fate. Cohesion species concept- populations evolve as genetically cohesive units. Phylogenetic species concept- an irreducible grouping of organisms diagnosably distinct from other such groupings and within which there is a parental pattern of ancestry and descent. General lineages concept- species constitute segment of of population level lineage. Diagram where the branches show evolutionary lineages and common descent. Homoplasy-character similarities that are not due to common descent.
