Summary
Comparative anatomy
- Organisms have similar structure (homologies) even if they have different
ecologies
- Vestigial organs imply trace of earlier history
- Ontogeny shows divergent adult morphologies started from very similar beginings
Taxonomy
- Life is hierarchical (a "tree of life")
Geology
- Earth is ancient
- Small processes over time yield big changes
- Fossils occur in the order predicted by comparative anatomy
Biogeography
- The same environment in different continents yields different organisms