What evidence do we have for evolution?
The evidence for evolution comes in many different biological areas.
- Firstly, anatomy. As species have many similar physical features, we can see that these features were present in a common ancestor. These are called homologous structures.
- Molecular biology also provides evidence for evolution. DNA and the genetic code being similar shows that species are related, and you can compare these strings of DNA can show how related they are.
- Biogeography is the study of where organisms physically are - we'll learn more about this in Topic 4A-C. It explores how the unique features of an island species reflect the evolution and geological change.
- Fossils are the most well-known and well-documented way to explain and see evolution. Whether this is a plant or animal species, fossils show what features now-extinct species had, and how they are related to present-day species.
- We can directly observe small-scale evolution in a study called direct observation. We can see this in organisms with short lifecycles like insects that become pesticide-resistant, or bacteria that become antibiotic-resistant.