Biology Presentation-Darwinism

Darwinism The Origin of the Species by Natural Selection Plato Believed there were two worlds A real world that is ideal and eternal An illusory world of imperfection perceived by senses Aristotle Believed that all living forms could be arranged on a scale of increasing complexity. This was known as scala naturae. Charles Darwin Son of a prominent physician in England At age 16 his father sent him to the University of Edinburgh to study medicine Enrolled at Christ College at Cambridge to become a clergyman In December of 1831 at the age of 22 he sailed with the crew of the HMS Beagle 1844 – Wrote a long essay on the origin of species by natural selection 1859 – Published The Origin of the Species by Natural Selection Others Influencing Darwin Linnaeus George Cuvier Jean Bapiste Lamark James Hutton Wallace Lyell Summary of Darwin’s Ideas Natural Selection is the differential success in reproduction, and its product is adaptation of organisms to their environment Natural selection occurs from the interaction between environment and the inherent variability in a population Variations in a population arise by chance but natural selection is not a chance phenomenon, since environmental factors set definite criteria for reproductive success. Variation and overproduction make natural selection possible Examples of Natural Selection in Action Average beak depth varies with rainfall Butterfly population adapted to a vegetation change in a ten year period Antibiotic resistant bacteria The Evidences for Evolution Artificial Selection Fossil Evidence Comparative Anatomy Embryology Comparative Biochemistry Biogeography Figure 22.2 Fossils of trilobites, animals that lived in the seas hundreds of millions of years ago