Evidence for Evolution

Comparative Anatomy (Homology) Similarity resulting from common ancestry

Homologous structures anatomical resemblances that represent variations on a structural theme that was present in a common ancestor Figure 22.14 Human Cat Whale Bat

Comparative embryology Anatomical homologies not visible in adult organisms Figure 22.15 Pharyngeal pouches Post-anal tail Chick embryo Human embryo

Molecular Homologies Genes and proteins that are shared among organisms inherited from a common ancestor

Anatomical resemblances among species Reflected in their molecules, genes, and gene products Figure 22.16 Species Human Rhesus monkey Mouse Chicken Frog Lamprey 14% 54% 69% 87% 95% 100% Percent of Amino Acids That Are Identical to the Amino Acids in a Human Hemoglobin Polypeptide

Biogeography Similar mammals that have adapted to similar environments, have evolved independently from different ancestors Sugar glider AUSTRALIA NORTH AMERICA Flying squirrel Figure 22.17

The Darwinian view of life Predicts that evolutionary transitions should leave signs in the fossil record Fossils of many such transitional forms have been found Figure 22.18

In science, a theory (e.g. evolution) Accounts for many observations, facts, laws, and data and explains and integrates a great variety of phenomena