PowerPoint presentation that highlights chapters 13 and 14 in Campbell's Essential Biology (3rd. edition). It can also be used for Miller & Levine's Biology (2006 Ed.) for chapters 15-18.

1. Evolution

4. Evolutionary Adaptation

5. Evidence of Evolution:Fossil Record Fossils chronologically ordered in rock layers

6. Evidence of Evolution:Biogeography Geographic distribution of species: Australian marsupials

7. HOMOLOGY Evidence of Evolution:Comparative Anatomy and Embryology

8. Evidence of Evolution:Molecular Biology Notice that a Chimp is more genetically related to a human than to an Old World Monkey!

9. Adaptive Evolution Natural Selection = Editing The finches of The Galapagos Islands: The original finch developed into 14 different species. What was the cause for the offshoots?

10. Darwinism Meets Genetics A population is the smallest unit of evolution. Natural selection acts on individuals. However the evolutionary impact of natural selection is only apparent in tracking how a population changes over time. Population Genetics emphasizes the extensive genetic variation within populations and tracks the genetic make-up of populations over time. Not all variation in a population is inheritable. Only the genetic component of variation is relevant to natural selection. Many variable traits in a population result from the combined effect of several genes. Polymorphism

11. Analyzing Gene Pools A Gene pool consists of all alleles (different forms a gene may have for a trait) in all the individuals making up a population. A reservoir for the next generation’s genes. Recall: Homozygous (RR) and Heterozygous (Rr) Dominant and Recessive (rr) Hardy Weinberg Formula (1908) Helps to calculate the frequencies of genotypes in a gene pool from the frequencies of alleles and vice versa. p2 + 2pq + q2 = 1 p = RR pq = Rr q = rr

12. Practice Using The Hardy-Weinberg Formula p2 + 2pq + q2 = 1 p = 0.6 q = 0.4 What are the genotypic frequencies of their offspring? 0.36 + 2(0.24) + 0.16 = 1 36% RR 48% Rr 16% rr

13. Microevolution 1. Genetic Drift Def: A change in the gene pool of a small population due to chance. The best measure of Darwinian fitness is the number of fertile offspring an individual leaves.

14. Genetic equilibrium- allele frequencies remain constant. To maintain equilibrium… Random mating Population must be very large No immigration or emmigration No mutations No natural selection

15. Types of Genetic Drift a. The Bottleneck Effect An event that usually reduces the overall genetic variability in a population. b. The Founder Effect Genetic Drift in a new colony i.e. The Galapagos Islands

16. Microevolution Cont. 2. Gene Flow Def: The genetic exchange with another population. 3. Mutations A change in an organism’s DNA sequence. Ultimate source of genetic variability. 4. Natural Selection Directional Selection (selecting in favor of an extreme phenotype) Disruptive (Diversifying) Selection (leads to a balance between two or more contrasting phenotypic forms) Stabilizing Selection (maintains variation in a narrow range)

18. Immediate Benefits

19. Long term Disaster

22. Zygote: fertilized egg

23. Pre-zygotic (factors that impede mating between species or hinder fertilization of eggs if mating is attempted)

25. Mechanisms of Speciation Allopatric Speciation A population forms a new species while geographically isolated from its parent population. Sympatric Speciation A small population becomes a new species in the midst of a parent population

28. Notice how the hybrid bread wheat has a set of chromosomes from each of its ancestors: T. monococcum (AA), Triticum (BB), T. turgidum (AA BB), T. tauschii (DD) What can you notice about T. aestivum that might make it a good hybrid and the most important wheat species today?

29. Relative Dating:Fossil Record Fossils chronologically ordered in rock layers

30. Radioactive Dating

32. Continental Drift

33. Meteor of this size would have lowered the temperature of Earth due to the blocking of the sun by atmospheric dust. Theory: 65 million years ago a catastrophic event occurred killing off the dinosaurs and about ½ of the species inhabiting the Earth in a 10 million year time span.

34. The Origin of Life Stage 1: Abiotic Synthesis of Organic Monomers Amino Acids Chains of nucleotides Chains of DNA bases Chains of RNA bases Building blocks of protein Sugars Lipids ATP

35. The Origin of Life Stage 2: Abiotic Synthesis of Polymers Monomers, such as amino acids, spontaneously fused together to form proteins.

36. The Origin of Life Stage 3: Origin of Self-Replicating Molecules inheritance Ribozyme: catalytic RNA used to fuel RNA replication

37. The Origin of Life Stage 4: Formation of Pre-cells Molecular packages with some properties of life. The gap between pre-cells and true cells is enormous! Natural Selection

38. The origin of eukaryotic cells Endosymbiotic Theory Membrane bound nuclear material Organelles More complex than prokaryotic cells Ancestors to fungi, plants and animals

39. Concept Map Section 17-2 Evolution of Life Early Earth was hot; atmosphere contained poisonous gases. Earth cooled and oceans condensed. Simple organic molecules may have formed in the oceans.. Small sequences of RNA may have formed and replicated. First prokaryotes may have formed when RNA or DNA was enclosed in microspheres. Later prokaryotes were photosynthetic and produced oxygen. An oxygenated atmosphere capped by the ozone layer protected Earth. First eukaryotes may have been communities of prokaryotes. Multicellular eukaryotes evolved. Sexual reproduction increased genetic variability, hastening evolution.

40. Convergent Evolution Process by which unrelated animals come to look like each other. Dolphin Penguin Shark

41. Tempo of Evolution Spurts of relatively rapid change Slow adaptations

42. Unrelated Related Intense environmental pressure Similar environments Inter-relationshiops Small populations Different environments Convergent evolution Punctuated equilibrium Adaptive radiation Coevolution Extinction Flowchart Section 17-4 Species that are in under under form in in can undergo can undergo can undergo can undergo can undergo

43. Classifying the Diversity of Life Systematics Reconstructing evolutionary history Radioactive dating = tool The study of biological diversity: past and present Taxonomy Identification, naming and classification of species Pioneer: Carolus Linnaeus (1707-1778) Binomial Nomenclature Homo sapien

44. Hierarchical Classification Which step is more specific? Class or Genus? How is Domain Eukarya different from Bacteria and Archaea?

46. Tree is based on homologous structures, NOT analogous.

48. 6 Kingdoms vs. 3 Domains Archaea-bacteria Eubacteria ?