1. Evidence of Evolution Key Concept
Evidence For This Process Could Be Found In:
The Fossil Record
The Geographical Distribution of Living Species
Homologous Structures of Living Organisms
Similarities In Early Development

2. How do we study Evolution?

3. Comparative studies
Researchers use comparative studies to establish evolutionary relationships between organisms

4. Homologous Body Structures
Scientists Noticed Animals With Backbones (Vertebrates) Had Similar Bone Structure
May Differ In Form or Function
Arms, Wings, Legs, Flippers

5. Homologous Body Structures

6. Homologous Body Structures
Not All Serve Important Functions
Vestigial Organs
Appendix In Man
Legs On Skinks

7. Comparative anatomy Comparing specific body structures
Analogous structures have a similar function but the structure is different
Ex the wing of an insect and the wing of a bird

8. Homologous structures are similar in structure but may have different functions
Ex) human hand, cat paw, whale flipper, bat wing

9. Similarities In Early Development
Embryonic Structures Of Different Species Show Significant Similarities
Embryo – early stages of vertebrate development

10. Human Fetus – 5 weeks

11. Comparative embryology
The comparison of embryonic development
Early development is similar in many species
The closer the relationship between species the more similar is development

12. Comparative cytology Observing similarities in cell structures
All cells have some common organelles that perform identical functions
Plasma membrane, cytoplasm, and ribosomes

13. Fossil Record Earth is Billions of Years Old
Fossils In Different Layers of Rock (sedimentary Rock Strata) Showed Evidence Of Gradual Change Over Time

14. Fossils Imprints of bacteria, leaves or footprints
Insects, pollen, or flower parts in amber
Tools or pottery shards
Bones of organisms in sedimentary rock
Cave drawings

16. Macroevolution
Long term changes that make a new species

17. General patterns for evolution
Divergent evolution – different groups evolve from one ancestor

18. Convergent evolution – two or more different groups evolve so that they resemble one another strongly

19. Adaptive radiation – organisms spread into new environments and become adapted through natural selection