• many individuals challenged prevailing religous philosophical beliefs

Sources of Evidence for Evolution

• fossils=traces of remains of past life found in sedimentary rock

• biogeography=the study of past and present geographical distributions of species populations

• anatomy=comparing structures within and between species

• embryology=the study of early, pre-birth stages of an organisms development

• DNA evidence= similarities in organisms genetic sequences suggests a common ancestor

fossil record =containts the remains and traces of past life buried within sedimentary rock

• reveals the history of Earth and kinds or organisms alive in the past

Evidence from Fossils

• the law of superposition

  • each rock layer is older than the one above it

• transitional fossils

  • show intermediary links between groups of organisms

  • common characteristics of two now separate groups

• vestigial structures

  • a structure that is a reduced version of a structure that was functional in the organisms ancestor

Evidence from Biogeography

• study of past and present geographical distribution of species populations

• used by Darwin and Wallace

  • species evolve in one location then spread to other regions

• geographically close environments are populated by related species

• environmentally similar but geographically separated locations do not guarantee related species

• closely related species are almost never found in exactly the same location or habitat

• super continent separated, spreading organisms over different places

Evidence from Anatomy

• homologous structures=similar structures, different function

• analogous structures = structures that do not have a common origin, similar function

Evidence from Embryology

• study of early pre birth stages of an organisms development

• shared ancestry

Evidence from DNA

• similar DNA sequences