ANTH 168 Lecture Notes - Lecture 5: Chronospecies, Punctuated Equilibrium, Orthogenesis

• School: Binghamton University
• Department: Anthropology
• Course: ANTH 168
• Professor: merriwether

Document Summary

Chapter 4, the evolution and classification of species. Biological species concept: is the most widely accepted species concept. Anagenesis: species formation without branching of the evolutionary line of descent. Chronospecies: is a species derived from a sequential development pattern which involves continual and uniform changes from an extinct ancestral form on an evolutionary scale. Cladogenesis: the formation of a new group of organisms or higher taxon by evolutionary divergence from an ancestral form. Reproductive isolation: refers to the situation where different species may live in the same area, but properties of individuals prevent them from interbreeding. The things which stop species or groups of organisms reproducing sexually are called isolating mechanisms. Speciation: the formation of new and distinct species in the course of evolution. Adaptive radiation: the diversification of a group of organisms into forms filling different ecological niches. Gradualism: the hypothesis that evolution proceeds chiefly by the accumulation of gradual changes (in contrast to the punctuationist model).