Type of entry:
- A unit outline that may be expanded into a summer field course.
Type of activity:
- Hands-on activity
- Inquiry based unit
- Possible off site activity.
- Life Science
- Anatomy and Physiology.
Notes for Teacher:
Until recently, dinosaurs were looked upon as sluggish, dim witted beasts dragging their tails in the swamps. With the commercialization of Jurassic Park, young people today have a very different view of dinosaur life, but what they probably do not understand is the process by which scientists have revised their interpretation of the fossil record. This unit is intended to help students engage in and appreciate the process by which we can use the fossil record to gain a better understanding of the life history of dinosaurs. Although the unit focuses on one particular group of organisms, it can serve as an introduction to the more general methods of paleontology. Moreover, it is designed to help students hone their skills in general hypothesis testing so that they will be better prepared for future inquiry into other areas of science.
The unit, which I've expanded into a summer field course, does require a great deal of advanced preparation on the part of the instructor. However, tremendous resources exist for teachers to educate themselves about current trends in dinosaur paleontology, and with the help of several informative publications and videos, and the services of several excellent museums (including one accessible on the Internet), the needed background information can be gained more quickly than one might think.
Required of students:
- A general background in evolutionary theory, with a firm understanding of the
theory of natural selection.
- A general understanding of basic geologic concepts including plate tectonics.
Class time needed:
I've taught this unit over a period of five days. Certain individual exercises can be used as one(1) period activities. I've expanded the unit into a three week summer field course that I've taught using the resources of several museums of paleontology in the American West. Because of the excellent outside support of these institutions, I feel that it would be feasible for any biology teacher with the time and motivation to teach his or her own field course using my model.
The Activity Unit:
The purpose of this unit is to have students understand how the scientific method is used in studying the life history of dinosaurs. Using readings from a variety of publications, video productions, and the resources available through museums of paleontology, students are challenged to think of how we can best interpret the fossil record pertaining to dinosaurs. Students investigate themes in dinosaur evolution, anatomy, physiology, and behavior, as well as ideas regarding the formulation of their own hypotheses pertaining to dinosaur life, and they are further challenged to describe the ways in which they would obtain evidence to support their ideas. I added a field component for an expanded version of this unit that I have taught over a three week period in the summer.
I use a variety of excerpts from published sources to share with students. The single most informative resource is Digging Dinosaurs (John R. Horner and James Gorman, Workman Publishing, 1988). I use diagrams and other excerpts from the Dinosaur Data Book (The Diagram Group, Avon Books, 1990). For the summer field course, I require students to read Digging Dinosaurs and another book, Dinosaurs Rediscovered (Don Lesse, Simon and Schuster, New York, 1992).
As an aid in describing various aspects of field work, I use video clips from Public Broadcasting's production of the Infinite Voyage series segment, The Great Dinosaur Hunt (Metropolitan Pittsburgh Public Broadcasting, Inc., and the national Academy of Sciences, 1988). Most importantly, I use the resources of the University of California at Berkeley's Museum of Paleontology for help in acquiring fossil specimens and casts. Also, Berkeley's Virtual Museum is accessible on the Internet. I urge teachers to contact local museums and universities for help in locating specimens for use in the classroom.
In conducting the summer field course, I have collaborated with the Field School of Paleontology at Montana State University's Museum of the Rockies. The Field School runs several one week sessions over the summer that are open to students 15 years of age and older. I have a list of several other summer field study programs available to students and teachers.
Description of Unit:
The unit addresses the following questions, and students are challenged throughout the unit to develop their own hypotheses in response:
- What methods can be used to interpret the fossil record for dinosaurs?
- What were the circumstances under which dinosaurs evolved, and what effect did their evolution have on other organisms?
- What can we tell about dinosaur anatomy and physiology?
- What can we tell about dinosaur behavior?
- What were the circumstances surrounding the extinction of dinosaurs?
- What social responsibility do we have dealing with fossils on public land?
What follows are several examples
of specific topics covered in the unit:
I introduce the unit by asking students to pose questions that they themselves have about the life history of dinosaurs. After generating this list on the board, I ask them what kinds of data one would have to collect in order to address these questions. I go on to ask them to identify the questions they think paleontologists have already answered definitively. What this process reveals, of course, is that the data we have from the fossil record about dinosaurs is very incomplete, and we have many more questions than answers.
In addressing the methods of paleontology, I emphasize the careful, painstaking work involved, and I point out that complete fossil specimens are extremely rare. I ask students how paleontologists might hypothesize about how missing pieces of skeletons are put together.
After describing the early evolutionary history of dinosaurs, I pose questions about the adaptive significance of some of their ancestral features (i.e., bipedal, dog sized carnivores). Later, I ask students why natural selection might have favored the evolution of the tremendous size found in the sauropods, the huge herbivorous dinosaurs. Of course, students are also asked to identify the disadvantages of being so large. Other questions have students relate dinosaur evolution to global geologic changes.
One of the more intriguing physiological questions relating to dinosaurs has to do with their thermoregulation. In this regard, students learn to distinguish among the following terms: endothermy, ectothermy, homeothermy, poikilothermy, tachymetabolic, and bradymetabolic. As a consequence, students learn the imprecise meanings of the terms "warm-blooded" and "cold-blooded", and they are challenged to think about the more complex nature of thermoregulation. For example, it has been suggested that some dinosaurs exhibited "mass homeothermy." That is, they were homeothermic and tachymetabolic, but no endothermic.
A specific exercise concerning dinosaur behavior has students examine a cast of the skull of Pachycephalosaurus, a bipedal herbivore with a thick dome of bone on its head. Along with the dome, the skull shows students the size of the braincase, the bones in the nasal cavity, and those surrounding the orbits of the eyes. Along with suggestions that this animal had sharp eyesight and a keen sense of smell, students come up with several intriguing possibilities concerning the function of the domes. I then challenge them with questions about how they would test their ideas. For example, if they hypothesize that males used the domes in head-butting contests for mating rights, I ask them what further evidence they would need in species that might serve as models for their ideas. Using other bones, fossil teeth, and egg shells fragments, I lead students through a series of similar exercises in hypothesis testing.
My method of student evaluation involves having them write a "grant proposal" in which they need to propose their own hypothesis concerning some aspect of dinosaur life. The proposal must include the type of data they intend to collect in attempting to support their hypothesis, and the methods by which they propose to collect these data.
AN INNOVATIVE ACTIVITY IN BIOLOGICAL SCIENCE
The most innovative facet of my teaching engages students in the study of dinosaur paleontology. I've developed a curricular unit appropriate for a sophomore biology course in which students of all abilities are challenged to think critically about the life history of dinosaurs. In addition, I've developed and taught a three(3) week Field Course in Dinosaur Paleontology, now an accredited course offered to a select group of Marin Academy juniors and seniors during alternate summers. Built upon the natural fascination young people have with dinosaurs, both the dinosaur unit and the Field Course are highly successful innovations that can be incorporated into the curricula of high schools elsewhere.
Dinosaur paleontology has changed radically since I was a boy, thirty-five years ago, when dinosaurs were looked upon as dim witted beasts dragging their tails in the swamps. With the commercialization of Jurassic Park, young people today have a very different view of dinosaur life, but what they probably do not understand is the process by which scientists have revised their interpretation of the fossil record. It is this process of inquiry that I want my students to engage in and appreciate.
The dinosaur paleontology unit has students investigate themes in dinosaur evolution, anatomy, physiology, and behavior, as well as ideas regarding their extinction. The unit incorporates readings from a variety of recent publications, but emphasizes field work, especially that described in Jack Horner's Digging Dinosaurs (Workman Publishing, 1988). Students view several video clips of Horner and other paleontologists performing and interpreting their work, but the emphasis of the unit is on having students work with actual fossil specimens and formulating their own hypotheses pertaining to dinosaur life. I obtain fossil specimens and casts from the Museum of Paleontology at the University of California at Berkeley. Using actual fossils and casts is the key to the unit's success.
One specific exercise has students examine a cast of the skull of Pachycephalosaurus, a bipedal herbivore with a thick dome of bone on its head. Along with the dome, the skull shows students the size of the braincase, the bones in the nasal cavity, and those surrounding the orbits of the eyes. Based upon what they observe, students are asked to construct hypotheses concerning this dinosaur's life history. Along with suggestions that this animal had sharp eyesight and a keen sense of smell, students come up with several intriguing possibilities concerning the function of the domes.
I then challenge them with questions about how they would test their ideas further. For example, if they hypothesize that males used the domes in head-butting contests for mating rights, I ask them what further evidence they would need in order to support their position. Also, I have them think about examples of extant species that might serve as models for their ideas. Using other bones, fossil teeth, egg shell fragments and reproductions of dinosaur trackways, I lead students through a series of similar exercises in hypothesis testing. Berkeley's Virtual Museum of Paleontology on Internet is now an additional resource for this unit, although I feel strongly that it cannot replace the value of hands-on work with the fossils themselves.
Perhaps the single most valuable thing I've done in my professional career is to design and teach the Field Course in Dinosaur Paleontology. With the help of the Field School at Montana State University and the Royal Tyrell Museum in Alberta, Canada, I led eight students over 3,500 miles on a 3 week trip this past summer introducing them to the methods of paleontology. Prior to our departure, each student did extensive reading and researched a specific topic that was then presented and discussed en route to our dig sites. Students performed extensive field work and toured museums in Montana and Alberta, and exchanged ideas with leading researchers including Jack Horner and Phil Currie. Our week working with paleontologists at MSU's Camp Makela was the cornerstone of the course. As a result of this experience, I now have a successful model for anyone interested in developing his or her own summer field course in dinosaur paleontology.