Doc #1 Evidence of Evolution Name: Period: Convergent Evolution What does it mean to converge? What is the same about the animals under convergent evolution? Divergent Evolution What does it mean to diverge? What is the same about the animals under divergent evolution? Embryological Evidence Guess which animal each of these will develop into? Why do you think they are so similar? Did they converge or diverge? DNA Evidence What can DNA tell us about relatedness in organisms? Do related individuals have more or less DNA in common? Fossil Evidence Where are the oldest fossils? Which came first, the Mammoth or the Pterodactyl? 1
Evidence of Evolution Textbook Biology, The Dynamics of Life. 2002. Chapter 15.1 (pp. 401-411) Chapter 15.2 (pp. 412-421) 3B Standard Outline I. Types of Evolution a. Divergent - (p. 420) i. Start similar, change to become different ii. Supported by homologous structures b. Convergent- (p. 421) i. Start different, change to become similar ii. Supported by analogous structures II. Evidence for Evolution a. Comparative Anatomy i. Homologous Structures- same structure, different function (p. 408) ii. Analogous Structures- different structure, same function (p. 409) iii. Vestigial Structures- leftover structures from ancestors, not used presently (p. 410) b. Embryology- developmental stages of vertebrates are very similar c. Biochemistry- comparisons of DNA and proteins show relatedness among all living things (p. 411) d. Biogeopgraphy i. Pangea ii. Distribution of fossils iii. Distribution of present day organisms e. Direct Observations i. Galapagos Finches ii. Resistance to antibiotics iii. Resistance to pesticides iv. Artificial Selection (Dog Breeds) f. Natural Selection- see Standard 2B 2
3B Doc #2Types of Evolution Hypothesis: Hypothesis: Examples: Examples: Explanation: Explanation: 3
3B Doc #3 Types of Structures Comparative Anatomy How are they the same? Hypothesis of why they are the same: How are they different? Hypothesis of why they are different: What type of Evolution supports this type of structure? Structure = Function= How are they the same? Hypothesis of why they are the same: How are they different? Hypothesis of why they are different: What type of Evolution supports this type of structure? Structure = Function= 4
Types of Evolution Practice Convergent: Ecological pressures cause a similarity in structure or function, but not from a common ancestor. Divergent: Evolution arising out of differences in organism which had a common ancestor. Which graph on the left represents convergent evolution? Which graph on the left represents divergent evolution? Description Convergent Divergent In the ocean surrounding Antarctica, there are fish that survive the cold water by using a molecule made of glycoproteins that circulates the blood and keeps it from freezing. Certain kinds of worms that live in the Arctic ocean also make antifreeze proteins that help them live in icy water. The Galloti atlantica and Galloti galloti lizards evolved through natural selection from a common ancestor into a wide variety of different looking lizards. Whales, sharks, and penguins all have streamlined bodies and fins/flippers for moving in water even though they belong in different classes of animals (mammals, fish, and birds) The Galápagos tortoises share a common ancestor, but have necks of different lengths to best reach the food they need in their environment. This kind of evolution is proven by DNA analysis and results in organisms with different ancestors becoming more alike as they adapt to similar environments. Adaptive radiation is an example of this type of evolution The Galápagos finches evolved through natural selection from a common ancestor into a wide variety of different looking species. Ostriches (birds) and giraffes (mammals) are both native to the savannahs of Africa. They share the same characteristic of a very long neck. The beaver in North America and the capybara in South America share a common ancestor, but have evolved over time to look different Ostriches are native to the savannahs of Africa, while penguins live in the polar regions. Although ostriches and penguins are closely-related, they look very different. 5
A. Comparative Anatomy Shown below are images of the skeletal structure of the front limbs of 6 animals: human, crocodile, whale, cat, bird, and bat. Each animal has a similar set of bones. Colors code each of the bones according to this key: Humerus [ ] Ulna [ ] Radius [ ] Carpals [ ] Metacarpals [ ] Phalanges [ ] 6
For each animal, indicate what type of movement each limb is responsible for. Animal Human Whale Cat Bat Bird Crocodile Primary Functions Compare the skeletal structure of each limb to the human arm. Relate the differences you see in form to the differences in function. Animal Comparison to Human Arm in Form Comparison to Human arm in Function Human Whale has a much shorter and thicker humerus, radius, and ulna. Much longer metacarpals. Thumb has been shortened to a stub. The whale fin needs to be longer to help in movement through water. Thumbs are not necessary as the fins are not used for grasping. Whale Cat Bat Bird Crocodile 7
Compare the anatomy of the butterfly and bird wing below 1. What is the function of each of these structures? 2. How are they different in form? Give specific differences. Compare the overall body structure of the cave fish and the minnow below. 3. What is the biggest, most obvious difference between the body structures of these two fish? 4. Assume the two fish came from the same original ancestor. Why might the cave fish have evolved without eyesight? 5. What kind of sensory adaptation would you hypothesize the cave fish has to allow it to navigate in a cave, including catching and eating food? 8
You have now studied three different types of anatomical structures: Homologous structures show individual variations on a common anatomical theme. These are seen in organisms that are closely related. 1. Give an example of a homologous structure from this activity: Analogous structures have very different anatomies but similar functions. These are seen in organisms that are not necessarily closely related, but live in similar environments and have similar adaptations 2. Give an example of an analogous structure from this activity: Vestigial structures are anatomical remnants that were important in the organism s ancestors, but are no longer used in the same way. 3. Give an example of a vestigial structure from this activity: 4. Below are some vestigial structures found in humans. For each, hypothesize what its function may have been. Structure Wisdom Teeth Possible Function? Appendix Muscles for moving the ear Body Hair Little Toe Tail Bone 5. How are vestigial structures an example of evidence of evolution? 9
B. Embryology Organisms that are closely related may also have physical similarities before they are even born! Take a look at the six different embryos Labeled PHASE I. (Blue) Species Hypothesize which embryo is from each of the following organisms: Human Chicken Rabbit Tortoise Salamander Fish Embryo Take a look at the six different embryos Labeled PHASE 2. (Yellow) These are older, more developed embryos from the same organisms. Take a look at the six different embryos Labeled PHASE 3. (Pink) These are embryos at their most advanced stage, shortly before birth. Species Human Chicken Rabbit Tortoise Salamander Fish Embryo Describe how the embryos changed for each of these organisms from their earliest to latest stages. Species Embryo Species Anatomical Changes From Early to Late Stages Human Chicken Rabbit Tortoise Salamander Fish 1. Look again at the six embryos in their earliest stages. Describe the patterns you see. What physical similarities exist between each of the embryos? 2. Does this suggest an evolutionary relationship? Explain how.these embryos can be used as evidence of a common ancestor between each of these six organisms. 10
C. Biochemistry Cytochrome C is a protein found in mitochondria. It is used in the study of evolutionary relationships because most animals have this protein. Cytochrome C is made of 104 amino acids joined together. Below is a list of the amino acids in part of a cytochrome protein molecule for 9 different animals. Any sequences exactly the same for all animals have been skipped. For each non-human animal, take a highlighter and mark any amino acids that are different than the human sequence. When you finish, record how many differences you found in the table on the next page. 42 43 44 46 47 49 50 53 54 55 56 57 Human Q A P Y S T A K N K G I Chicken Q A E F S T D K N K G I Horse Q A P F S T D K N K G I Tuna Q A E F S T D K S K G I Frog Q A A F S T D K N K G I Shark Q A Q F S T D K S K G I Turtle Q A E F S T E K N K G I Monkey Q A P Y S T A K N K G I Rabbit Q A V F S T D K N K G I 58 60 61 62 63 64 65 66 100 101 102 103 104 Human I G E D T L M E K A T N E Chicken T G E D T L M E D A T S K Horse T K E E T L M E K A T N E Tuna V N N E T L R E K A T S - Frog T G E E T L M E S A C S K Shark T Q Q E T L R I K T A A S Turtle T G E E T L M E D A T S K Monkey T G E D T L M E K A T N E Rabbit T G E D T L M E K A T N E Animal Number of Amino Acid Differences compared to Human Cytochrome C Animal Number of Amino Acid Differences compared to Human Cytochrome C Horse Shark Chicken Turtle Tuna Monkey Frog Rabbit Molecular Biology Summary Questions 1. Based on the Cytochrome C data, which organism is most closely related to humans? 2. Do any of the organisms have the same number of differences from human Cytochrome C? In situations like this, how would you decide which is more closely related to humans? 11
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Biology 3B Evidence of Evolution Pretest Name: Period: 1. Which pairing is an example of convergent evolution? a. bats & mice b. mice & birds c. bats & birds 2. Which pairing is an example of divergent evolution? a. bats & mice b. mice & birds c. bats & birds 3. A pattern in which species experience long, stable periods interrupted by brief periods of rapid evolutionary change is called a. gradualism. b. punctuated equilibrium. c. convergent evolution. d. divergent evolution a. Analogous Structure d. Vestigial Structure b. Homologous Structure e. Divergent Evolution c. Convergent Evolution 4. pattern of evolution where similar traits are seen among unrelated species 5. pattern of evolution where different traits are seen among related individuals 6. structures that are used for different purposes but are similar in structure 7. structures that have same function, but are different in structure 8. structure not currently being used but was used by ancestors 9. Which of the following is not evidence that evolution through natural selection has occurred? a. embryological development b. biochemistry c. adaptations d. extinct organisms e. vestigial structures f. remnant of past species in fossils a. Fossil evidence e. DNA/molecular evidence b. Comparative anatomy f. Embryology c. Natural selection g. Direct Observation d. Biogeography 10. Many strains of bacteria have become resistant to Penicillin in the last 20 years. 11. Darwin s mechanisms by which evolution occurs, which depends upon survival of the fittest 12. Study of the structures of various animals or plants to show similarities or differences between organisms 13. Monkeys of South and Central America have prehensile tails, meaning that their tails can be used to grasp objects. The tails of African and Asian monkeys are not prehensile. 14. Wolves and domestic dogs little difference in their biochemistry. 15. Fish, pigs, humans, chicks, and cows are undistinguishable at 2 weeks old. 16. Preserved physical evidence of ancient organisms found in soil layers. 13