1. Zoology and Evolution

2. Zoology The scientific study of animals What is an animal?

3. Evolutionary Tree of Life

4. Animals Multicellular eukaryotes Heterotrophs (consumers) Develop through a blastula stage Motile at some stage of their life

5. Choanoflagellate Protozoan Simple colonial flagellates No specialization Precursor to Metazoa

6. Spherical Colonies of Choanoflagellates Reproduction of the whole cell aggregate through gametes Cell specialization

7. Animal Kingdom Includes Very Diverse Organisms

8. Cell level of specialization Porifera

9. Tissue level of specialization True tissues –Endoderm –Ectoderm Example –Cnidaria

10. Organ level of specialization Tissues form organs Three germ layers –Ectoderm –Mesoderm –Endoderm Example –Platyhelminthes

11. Complete alimentary canal Mouth and anus Example –Nematoda

12. Internal body cavity - Coelom Organs suspended inside body cavity Example –Annelida

13. Invertebrates – Animals without a backbone

14. Vertebrates – animals with a backbone

15. Evolution Process of organic development and change –Continual process – Driven by the environment –Organisms have built in potential for change

16. Perpetual Change

17. Common Descent Phylogeny –Common descent through branching lineages Evidence –Homologies – similarity between organism that occur because of common ancestry Structural Genetic

18. Skeletal Homologies Similarities because of common descent

19. Skeletal Homologies Similarities because of common function

20. Evolutionary Relationships Revealed During Embryonic Development

21. Multiplication of Species Reproductively distinct populations of organisms –Usually but not always differ in form –No interbreeding between species in the wild Species split and develop into new species

22. Gradualism and Punctuated Equilibrium Gradualism –Small changes accumulate over time –Steady rate of change Punctuated equilibrium –Bursts of rapid change followed by little change –Rate of change varies

24. Natural Selection

26. Responses to Selection

27. Sexual Selection Results in some sexual dimorphism

28. Potential for Variation

29. Modern View Microevolution –Small-scale changes –Change within a species Macroevolution –Large-scale changes –Formation of new species