Biological Evolution and Classification Scientific Evidence of Common Ancestry 211
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Biological Evolution and Classification Teacher Pages Purpose The purpose of this activity is to reinforce students understanding of the theory of evolution and some of the scientific evidence that supports this theory, including fossil records of organisms and similarities among characteristics of organisms. Correlations to Texas Essential Knowledge and Skills Note: Text with a line through it indicates this part of the TEKS is not being addressed in this activity. Some TEKS statements printed here end with a semicolon or the word and with nothing thereafter this indicates that further TEKS statements follow but are not included here. (7) Science concepts. The student knows evolutionary theory is a scientific explanation for the unity and diversity of life. The student is expected to: (A) analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental; (Readiness standard) (2) Scientific processes. The student uses scientific methods and equipment during laboratory and field investigations. The student is expected to: (C) (G) (H) know scientific theories are based on natural and physical phenomena and are capable of being tested by multiple independent researchers. Unlike hypotheses, scientific theories are well-established and highly-reliable explanations, but they may be subject to change as new areas of science and new technologies are developed; (Incorporated) analyze, evaluate, make inferences, and predict trends from data; and (Incorporated) communicate valid conclusions supported by the data through methods such as lab reports, labeled drawings, graphic organizers, journals, summaries, oral reports, and technology-based reports. (Incorporated) (3) Scientific processes. The student uses critical thinking, scientific reasoning, and problem solving to make informed decisions within and outside the classroom. The student is expected to: (A) in all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, including examining all sides of scientific evidence of those explanations, so as to encourage critical thinking by the student; (Incorporated) Teacher Pages 213
STAAR Biology: Assessment Activities Materials The following materials are included in the blackline masters for this station, which are available in color on the enclosed DVD. Station Information sheet Whale Skeleton Cards (1 set per station) DNA Sequence Cards (1 set per station) DNA Sequence Cladogram (1 per student plus 1 for the station) Horse Evolution Cards (1 set per station) Horse Evolution sheet (1 per station) Student Pages (1 set per student) Supplementary Resources Evolution and Natural Selection. Retrieved on May 26, 2011 from the University of Michigan website: www.globalchange.umich.edu/globalchange1/current/lectures/ selection/selection.html. Advance Preparation 1. Print one copy of all the blackline masters for this station from the enclosed DVD using a color printer. Color is essential to the station activities. Make a copy of the Student Pages (including the glossary) for each student. Make one copy of the DNA Sequence Cladogram for each student plus one for the station. 2. Laminate and cut out the Whale Skeleton Cards, Horse Evolution Cards, and DNA Sequence Cards included in the blackline masters. 3. Laminate the Horse Evolution sheet and the station copy of the DNA Sequence Cladogram. Station Setup 1. Laminate a copy of the Station Information sheet and tape it onto the station table. Students will use this to confirm the station is set up correctly. 2. Place the Whale Skeleton Cards, DNA Sequence Cards, laminated DNA Sequence Cladogram, Horse Evolution Cards, and laminated Horse Evolution sheet at the station. Procedures 1. Tell students to check the station setup against the Station Information sheet when they arrive at the table. If anything is missing or out of place, they should notify you. 214 Teacher Pages
2. Pass out a copy of the Student Pages, DNA Sequence Cladogram, and Horse Evolution sheet to each student. Instruct students to work through the procedures and answer the questions with their teammate(s). 3. As students work through the station activity, circulate around the room, checking their work and responding to questions. Guide to Student Responses Note: The suggested student responses presented below in italics represent the best possible answers to the student questions; actual student responses may vary. Essential Question What information can be gained by examining the fossil remains of the ancestors of modern organisms? By studying fossil remains, scientists can determine how closely related fossil organisms are to modern species. Fossil remains also give scientists insight into what environmental conditions were like where the fossil organisms lived. Activities and Questions 1. Pull out the Whale Skeleton Cards and arrange them in order from the oldest fossil to the most recent skeleton. What evidence did you use in deciding how to order the cards? Oldest to most recent: Rodhocetus balochistanensis, Ambulocetus natans, Orcinus orca. The fossils progress from a walking whale with front and hind legs (Rodhocetus balochistanensis), to a whale with shorter front legs and outstretched hind legs (Ambulocetus natans), to the most recent skeleton of a modern whale with flippers and no hind legs (Orcinus orca). 2. What do the fossil remains of earlier whales indicate about changes in the whales habitats over time? The fossil remains show whales with legs, feet, and a pelvis. These are all indicators that these early whales walked on land. 3. If two different species have homologous structures, what does this tell you about their evolutionary history? If two different species have homologous structures, they must share a common ancestor. 4. Find the DNA Sequence Cards and DNA Sequence Cladogram at the station. Notice that the DNA sequences for the shark, camel, and dolphin already appear on the cladogram. Teacher Pages 215
STAAR Biology: Assessment Activities Examine the DNA sequences of the animals on the DNA Sequence Cards and compare them to the DNA sequences of the shark, camel, and dolphin. The more closely the DNA sequences match, the more closely related the organisms are to each other. Based on the results of your comparison, place the cards for the fish, cow, hippopotamus, and whale in the correct places on the cladogram. Record your placements on the cladogram. SHARK AGG CCG GCT CCA ACC AGG CCC FISH AGG CCG GCT CCA ACC AGG CCG CAMEL AGG CAT AAA CCA ACC GTA TAC Last Common Ancestor COW AGG CCC AAA CCA ACC ATG CAC HIPPOPOTAMUS AGG CCC GCA CCA ACC GAT CAC WHALE AGG CCC CTT CCA ACC GAT CAC DOLPHIN AGG CCC CTT CCA ACC GAT TAC 5. Examine the DNA Sequence Cladogram and determine which organisms are most closely related based on their homologous structures. Justify your answers. The shark and the perch streamlined body shape and fins (dorsal, lateral, and caudal). The whale and dolphin streamlined body shape and fins (dorsal, lateral, and caudal). The similar body shapes and structures are the result of a common ancestor shared by each pair. 216 Teacher Pages
6. Sometimes organisms that do not have a common ancestor may have analogous structures (similar anatomies). Examine the cladogram and determine which organism(s) share analogous structures with the perch and shark. Describe the analogous structure(s) and explain why these similarities could exist in organisms that do not share a common ancestor. The whale and dolphin share analogous structures with the perch and shark. They have similar fins and streamlined bodies because all of them live in water and swim. 7. Locate the Horse Evolution Cards. Arrange these cards on the Horse Evolution sheet to show changes that have occurred in the anatomy of the horse from its most ancient ancestor to modern horses. Explain why you arranged the cards in the order you selected. Eohippus Oligohippus Merychippus Pliohippus Equus The number of toes these horses have decreases in number: The oldest fossil has four toes; oligohippus has three; mercyhippus also has three but two are not fully formed; pliohippus has one toe but remnants of two additional ones near the knee. The modern horse, equus, has only one toe, which has evolved into a hoof. While the toes have decreased in number, the skulls have increased in size. Teacher Pages 217
STAAR Biology: Assessment Activities 8. Examine the evolutionary changes in the anatomy of the horse that the completed Horse Evolution sheet illustrates. Describe the major changes that you observe. All parts of the horse s anatomy have become larger. The face is longer, and the cheek teeth have changed in number and size. The lower legs and feet have changed, and the number of toes has been reduced from four smaller toes to one large toe that we now call the hoof. I need to remember... DNA sequences are used to determine how closely related organisms are to one another. Examining fossil remains enables scientists to understand how modern organisms developed over time. 218 Teacher Pages
Biological Evolution and Classification Blackline Masters Contents Station Information sheet Whale Skeleton Cards DNA Sequence Cards DNA Sequence Cladogram Horse Evolution Cards Horse Evolution sheet Student Pages Blackline Masters 219
Station Information: Station Information: STAAR Biology: Assessment Activities Horse Evolution Sheet Eohippus Oligohippus Merychippus Pliohippus Equus Horse Evolution Cards Horse leg Horse leg Horse leg Horse leg Horse leg Horse skull Horse skull Horse skull Horse skull Horse skull DNA Sequence Cladogram SHARK AGG CCG GCT CCA ACC AGG CCC Rodhocetus balochistanensis (Balochistan walking whale) Orcinus orca (Killer whale) Whale Skeleton Cards Ambulocetus natans (Walking whale) FISH WHALE AGG CCC CTT CCA ACC GAT CAC COW HIPPOPOTOMUS AGG CCC GCA CCA ACC GAT CAC AGG CCC AAA CCA ACC ATG CAC DNA Sequence Cards AGG CCG GCT CCA ACC AGG CCG Last Common Ancestor CAMEL AGG CAT AAA CCA ACC GTA TAC DOLPHIN AGG CCC CTT CCA ACC GAT TAC 220 Blackline Masters
Whale Skeleton Cards Rodhocetus balochistanensis (Balochistan walking whale) Ambulocetus natans (Walking whale) Orcinus orca (Killer whale) Blackline Masters 221
STAAR Biology: Assessment Activities DNA Sequence Cards PERCH AGG CCG GCT CCA ACC AGG CCG COW AGG CCC AAA CCA ACC ATG CAC HIPPOPOTAMUS AGG CCC GCA CCA ACC GAT CAC WHALE AGG CCC CTT CCA ACC GAT CAC 222 Blackline Masters
DNA Sequence Cladogram SHARK AGG CCG GCT CCA ACC AGG CCC CAMEL AGG CAT AAA CCA ACC GTA TAC Last Common Ancestor DOLPHIN AGG CCC CTT CCA ACC GAT TAC Blackline Masters 223
STAAR Biology: Assessment Activities Horse Evolution Cards 224 Blackline Masters
Eohippus Horse leg Horse skull Oligohippus Horse leg Horse skull Horse Evolution Merychippus Horse leg Horse skull Pliohippus Horse leg Horse skull Equus Horse leg Horse skull Blackline Masters 225
STAAR Biology: Assessment Activities 226 Blackline Masters
Biological Evolution and Classification Student Pages Purpose The purpose of this activity is to reinforce your understanding of the theory of evolution and some of the scientific evidence that supports this theory, including fossil records of organisms and similarities among characteristics of organisms. Before You Begin Check to see that all the items are present and organized according to the Station Information sheet. If you notice a problem, notify your teacher immediately. Materials Whale Skeleton Cards (1 set per station) DNA Sequence Cards (1 set per station) DNA Sequence Cladogram (1 per student plus 1 for the station) Horse Evolution Cards (1 set per station) Horse Evolution sheet (1 per station) Activities and Questions Essential Question What information can be gained by examining the fossil remains of the ancestors of modern organisms? Discuss the essential question with your teammate(s) and record your answer. Student Pages 227
STAAR Biology: Assessment Activities 1. Pull out the Whale Skeleton Cards and arrange them in order from the oldest fossil to the most recent skeleton. What evidence did you use in deciding how to order the cards? 2. What do the fossil remains of earlier whales indicate about changes in the whales habitats over time? 3. If two different species have homologous structures, what does this tell you about their evolutionary history? 228 Student Pages
4. Find the DNA Sequence Cards and the DNA Sequence Cladogram. Notice that the DNA sequences for the shark, camel, and dolphin already appear on the cladogram. Examine the DNA sequences of the animals on the DNA Sequence Cards and compare them to the DNA sequences of the shark, camel, and dolphin. The more closely the DNA sequences match, the more closely related the organisms are to each other. Based on the results of your comparison, place the cards for the fish, cow, hippopotamus, and whale in the correct places on the cladogram. Record your placements on the cladogram. SHARK AGG CCG GCT CCA ACC AGG CCC CAMEL AGG CAT AAA CCA ACC GTA TAC Last Common Ancestor DOLPHIN AGG CCC CTT CCA ACC GAT TAC Student Pages 229
STAAR Biology: Assessment Activities 5. Examine the DNA Sequence Cladogram and determine which organisms are most closely related based on their homologous structures. Justify your answers. 6. Sometimes organisms that do not have a common ancestor may have analogous structures (similar anatomies). Examine the cladogram and determine which organism(s) share analogous structures with the perch and the shark. Describe the analogous structure(s) and explain why these similarities could exist in organisms that do not share a common ancestor. 230 Student Pages
7. Locate the Horse Evolution Cards. Arrange these cards on the Horse Evolution sheet to show changes that have occurred in the anatomy of the horse from its most ancient ancestor to modern horses. Explain why you arranged the cards in the order you selected. 8. Examine the evolutionary changes in the anatomy of the horse that the completed Horse Evolution sheet illustrates. Describe the major changes you observe. 9. Now that you have completed these questions, return to the essential question. Would you like to modify or change your answer? Write any modifications to your answer below. Note: Because other students are going to do the activity after you, be sure to put all the materials at the station back as you found them. Sometimes there will be materials that need to be renewed or replaced. If you need assistance or have any questions, ask your teacher. Student Pages 231
STAAR Biology: Assessment Activities I Need to Remember... Complete this part after class discussion of this station. I need to remember... 232 Student Pages
Glossary Analogous structures Analogous structures are structures found in different species that are anatomically similar due to adaptations to environmental factors. Anatomical Anatomical refers to the structure and organization of an organism. Cladogram A cladogram is a tree-like diagram showing evolutionary relationships among organisms. Evolution Evolution is the change in the traits of organisms or populations of organisms from generation to generation. Fossil A fossil is a mineralized remain or preserved impression of an organism that lived in a past geological time. Homologous structures Homologous structures are structures found in different species that are anatomically similar due to common ancestry. Student Pages 233
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