GEOL G114 Spring 2016 Dinosaurs and Their Relatives Name: _______________________ Lab Section: _______________________ Evolutionary Modification of Birds after Archaeopteryx Laboratory 12 ******** MEET IN THE ATRIUM OF JORDAN HALL FOR THIS LAB ******* The aim of this lab is to understand modern birds and to put their morphological developments into an evolutionary perspective. In lecture we cover some of the characteristics of modern birds, and compare the skeletal morphology of Archaeopteryx, an early bird from the Jurassic, to living birds. We also discuss the ancestry of birds, the possible mechanisms for the origin of flight, and the variety of specializations of modern birds. The objective of this laboratory session is to examine the characteristics of modern birds in light of their evolutionary developments, with emphasis on skeletal structure, specializations of feathers, beaks and bills, and the relationship of these features to habitats. Please answer the questions below and turn in this exercise today to your lab instructor. 1. The arrangement of the toes in pigeons works well for perching - three toes point forward and one points backwards. Other birds, however, have different toe arrangements, which can differ among clades. Describe in words and sketches the toe arrangement of the bald eagle, the great-horned owl, and the red-breasted merganser duck and contrast the habitats in which these three birds live. Please consult with your AI regarding habitats if necessary. (10 pts) Look at the cards for Special Adaptations of Feet and Aquatic Adaptations and modify your above response as necessary. Indiana University | Department of Geological Sciences 1 2. Feathers are first recorded in the earliest theropod dinosaurs and were subsequently modified for flight in Archaeopteryx and other early birds. In the radiation of birds, feathers have evolved into many specialized shapes, colors, arrangements and functions. A. Use the exhibit to learn why an owl's flight is almost silent compared to other birds. Sketch and explain. (10 pts) B. Using the exhibits, describe (or draw) down feathers, retrice feathers, and flight feathers and note their functions. (10 pts) Indiana University | Department of Geological Sciences 2 3. A. Sketch the major bones of a cardinal’s skeleton. Label the following: sternum, ribs, carpometacarpus (fused carpal and metacarpal bones), pygostyle, phalanges, femur, and tibiotarsus (fused tibia and tarsal bones). (10 pts) B. How are the carpals, metacarpals, phalanges, and tail of the cardinal modified from the ancestral Archaeopteryx? (5 pts) C. Are there any teeth in Archaeopteryx? The cardinal? (5 pts) Indiana University | Department of Geological Sciences 3 4. In contrast to Archaeopteryx, modern birds have lost teeth and modified the front of the skull into a beak. Beak shape in birds is closely related to diet. Sketch and describe the beak and the diet of the parrot, pelican, northern cardinal and red- tailed hawk. (10 pts) 5. Watercolors by William Zimmerman for the book Birds of Indiana are on display along the walls. A. Look at the cerulean warblers: what is the tree they are perched on? Does it belong to the seedless vascular plants, the gymnosperms or angiosperms? What features suggest this identification? (10 pts) B. Identify the tree in the pine warbler watercolor. Does this tree belong to the seedless vascular plants, the gymnosperms or angiosperms? (10 pts) Indiana University | Department of Geological Sciences 4 6. For this question, look at the part of the exhibit that covers vertebrates other than birds. A. Locate the gar skull: In lecture you learned about the temporal fenestrae in amniotes. What type of temporal fenestrae does the gar possess, if any? (10 pts) B. Find the coelacanth (lobe-finned fish) model, draw its anatomy, and on your drawing identify the pectoral and pelvic limbs or fins, the anterior and posterior positions, backbone and ribs. Does the coelacanth have temporal fenestrae? (10 pts) Indiana University | Department of Geological Sciences 5 .