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CASE TEACHING NOTES
for
“A Strange Fish Indeed: The ‘Discovery’ of a Living Fossil”
by
Robert H. Grant, School for Professional Studies, Saint Louis University
INTRODUCTION / BACKGROUND
This case study was developed very soon after the death of Marjorie Courtenay-Latimer (–) in May
of . My hope is that it serves, in part, as a tribute to the legacy of her contributions to science.
The case study was developed for use in an introductory freshman biology course. In this setting, it could be
used as a general introduction to the nature/methods of scientiﬁc inquiry at the very start of a semester or later
in the semester as an introduction to the topic of evolution. Additionally, this case could be modiﬁed for use
in a number of upper-level biology courses such as ichthyology (as a springboard into a discussion of ancient
ﬁsh lineages or ﬁsh evolution), evolutionary biology (as an introduction to evolutionary relationships between
classes of animals), or conservation ecology (as an illustration of the issues involved in studying rare animal species).
The case features photographs as well as ﬁctitious diary entries interspersed with actual quotations from
Marjorie Courtenay-Latimer’s writings to recreate the events surrounding Courtenay-Latimer’s ground
breaking “discovery” of a living (non-fossil) coelacanth (Latimeria chalumnae ) in .
The case follows a progressive disclosure format with students receiving diary entries in two parts. Part
I comprises a single diary entry that describes the day on which Courtenay-Latimer collected the ﬁrst
coelacanth specimen as well as a handout (Handout I) with a picture of what the ﬁsh would have looked
like when Courtenay-Latimer ﬁrst caught a glimpse of it in a pile of sharks, seaweed, starﬁsh, sponges, and
other ﬁsh on the deck of the Nerine. Part II is a collection of diary entries that chronicle communications
between Courtenay-Latimer and her colleagues over the course of the next month and a half in her attempt
to bring attention to her discovery. After each of these two parts, discussion questions are included. In
the concluding part (Part III), students are given a list of facts and two additional handouts (Handouts II
and III) that can be used in a number of ways to bring closure to the case depending on the instructor’s
particular interest (see “Classroom Management” below for one approach).
Objectives
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•
•
•
•
To expose students to an incident of scientiﬁc discovery
To introduce students to methods of formal scientiﬁc inquiry
To initiate discussion concerning communication within the scientiﬁc community
To illustrate evolutionary relationships between classes of animals
To understand the concept of homology and to cite examples of homologous structures
CLASSROOM MANAGEMENT
Before the start of this case, arrange students into small discussion groups of three to ﬁve. This can be done
randomly or non-randomly depending upon the instructor’s knowledge of group dynamics, student learning
styles, or communication styles within the classroom.
The case requires no outside preparatory work by the students, and can be presented and discussed within a
- to -minute class period.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Start the case by handing out Part I along with Handout I, giving the students  to  minutes to
individually read the diary entry and discussion questions and peruse the photograph on Handout I. Then,
give groups ﬁve to  minutes to discuss their answers to the discussion questions, ﬁrst in their groups and
then as a class, with the instructor (or students) recording the answers and observations on the board.
Next, hand out Part II and give the students another  to  minutes to read the diary entries and
discussion questions. Again, allow ﬁve to  minutes for discussion of answers to questions, compiling and
elaborating on answers as you go.
End the case by distributing Part III and Handouts II and III. I suggest reading the list of follow-up facts as
a class so that you may steer the discussion in the desired direction (evolution, conservation, etc.).
Handout II is included to illustrate an overview of vertebrate evolution and to highlight the position of the
coelacanth and its evolutionary relatives (i.e., Eusthenopteron ) in this tree. In this vein, Handout II facilitates
understanding that the discovery of a living coelacanth was a major scientiﬁc discovery from the perspective
not only of evolutionary biologists, but for the human species as well. (Here the instructor should stress that
what was found that day by Marjorie Courtenay-Latimer was not merely a ﬁsh, but a living example of one
of our most distant evolutionary relatives.)
Handout III goes further to provide an image of a fossil coelacanth in which students can note actual
anatomical features of the skeleton (in particular pectoral, pelvic, and caudal ﬁn bone structure).
Additionally, Handout III includes a recent photograph of a living coelacanth. This picture can be used
as a segue into a discussion of ecological/biological issues surrounding the coelacanth such as overﬁshing,
conservation, basic behavioral study, etc. You might even assign your students a small take-home project
that involves researching at some greater depth the current status of global coelacanth populations, the
evolutionary history of ﬁshes, or any other issues pertinent to the case.
BLOCKS OF ANALYSIS
Use of this case can lead to discussions of several diﬀerent topics, ranging from the scientiﬁc method to
evolution to the historical role of women in science. Topics emphasized depend upon the educational goals
of the instructor and the context in which the case is presented.
Coelacanths belong to Class Sarcopterygii. Other members of this class include both African and South
American lungﬁshes (Subclass Dipnoi) and four-legged terrestrial vertebrates (Subclass Tetrapoda).
While taxonomic classiﬁcation of these ﬁshes is in a state of perpetual ﬂux, instructors should stress the
evolutionary relationships of these groupings rather than the speciﬁc assignment of class or subclass to a
particular group. The history of the coelacanth is useful knowledge to have before presenting this case.
Coelacanths are thought to have arisen in the early Devonian Epoch. Around  species of fossil coelacanths
are known, most of which are thought to have gone extinct by the end of the Cretaceous. Fossil coelacanths
have been found on every continent except for Antarctica, with the majority of these species occurring in fresh
water. Close cousin to the coelacanth, Eusthenopteron, is the fossil ﬁsh species once cited as an intermediate
form linking ﬁsh to amphibian species. Eusthenopteron and coelacanths share many anatomical features, the
most important being the lobed ﬁns that were thought to be the precursors to arms and legs in terrestrial
organisms. As with the taxonomic classiﬁcation of coelacanths, evolutionary relationships between coelacanths,
Eusthenopteron, and modern tetrapods is also under constant debate and revision. Currently in favor are
theories that name fossil species such as Icthyostega and Panderichthyes as the most immediate ancestors of
tetrapods. Regardless of this theoretical ﬂuctuation, studying coelacanths can help students learn about
intermediate forms in the evolution and the appearance of new classes, families, and species.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Aside from learning about evolution through the study of coelacanths, the case provides students with a
window into the scientiﬁc method and the nature of scientiﬁc discovery. Instructors should stress the fact
that Ms. Courtenay-Latimer was not a trained ﬁsh biologist and that she very carefully researched her ﬁnd
and contacted pertinent authorities to obtain information. Also to be stressed is the fact that rather than
an intimate knowledge of ﬁsh biology leading to her discovery, it was curiosity, an observant eye, and a
good general sense of biology that led Ms. Courtenay-Latimer to her discovery. This is often the case with
scientiﬁc discovery, and students will beneﬁt by hearing about the “layman’s” role in science.
Another issue surrounding the coelacanth that others may ﬁnd of use in their classrooms is conservation.
Class discussion could be steered towards the ethics involved with collecting and studying potentially
endangered species. Questions found at the end of Parts I and II facilitate discussion of this issue.
Finally, an issue brought up in the discussion questions that bears elaboration is the fact that the coelacanth
was only “discovered” as deﬁned by western science. As is the case with many scientiﬁc (and especially
biological/species) discoveries, native peoples inhabiting areas in which the discoveries are made are often
already familiar with the phenomenon. Depending upon the speciﬁc instructor’s goals, time may be spent
upon alerting students to this culture-centric reality.
Please see the websites listed in the “References” section below for good background material concerning
virtually all aspects of coelacanths and their discovery by western science.
ANSWER KEY
Answers to the questions posed in the case study are provided in a separate answer key to the case. Those
answers are password-protected. To access the answers for this case, go to the key. You will be prompted for
a username and password. If you have not yet registered with us, you can see whether you are eligible for an
account by reviewing our password policy and then apply online or write to [email protected].
REFERENCES
Coelacanth Rescue Mission: http://www.dinoﬁsh.com/
Australian Museum Online: http://www.austmus.gov.au/ﬁshes/ﬁshfacts/ﬁsh/coela.htm
iucn—The World Conservation Union: http://www.iucn.org/
The Coelacanth: http://sacoast.uwc.ac.za/education/resources/ﬁshyfacts/coelacanth.htm
FURTHER READING
Courtenay-Latimer, M. . My story of the ﬁrst coelacanth. Occidental Papers of the California Academy of
Science :–.
Courtenay-Latimer, M. . Reminiscences of the discovery of the coelacanth. Cryptozoology :–.
Erdmann, Mark V. . An account of the ﬁrst living coelacanth known to scientists from Indonesian
waters. Environmental Biology of Fishes ():–.
Erdmann, Mark V., Roy L. Caldwell, Susan L. Jewett, and Agus Tjakrawidjaja. . The second recorded
living coelacanth from north Sulawesi. Environmental Biology of Fishes ():–.
Forey, Peter L. . History of the Coelacanth Fishes. London; New York: Chapman & Hall.
Greenwell, J. Richard. . The lady and the coelacanth: Remembering the zoological discovery of the
century. The Explorers Journal ():–.
Musick, John A., M.N. Bruton, and Eugene K. Balon. . The Biology of Latimeria chalumnae and
Evolution of Coelacanths. Dordrecht; Boston: Kluwer Academic Publishers.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Pearce, Jeremy. . Marjorie Courtenay-Latimer, naturalist, is dead at . The New York Times (June ,
 Monday, Late Edition—Final), Section B, Column , Foreign Desk; p. .
Smith, J.L.B. . A living ﬁsh of the Mesozoic type. Nature :–.
Smith, J.L.B. . The second coelacanth. Nature :–.
Smith, J.L.B. . Old Fourlegs, The Story of the Coelacanth. London; New York: Longmans, Green.
Thomson, Keith Stewart. . Living Fossil: The Story of the Coelacanth. New York: W.W. Norton.
Weinberg, Samantha. . A Fish Caught in Time: The Search for the Coelacanth. New York: HarperCollins.
Additional Internet Sites
Amazing Story. Canadian Museum of Nature.
http://www.nature.ca/discover/treasures/trsite_e/tranimal/tr3/tr3.html
A nice online exhibit detailing some of the history surrounding coelacanths.
Ancient Creature of the Deep. NOVA.
http://www.pbs.org/wgbh/nova/ﬁsh/
This website, developed as a companion to the NOVA television program Ancient Creature of the Deep,
includes copies of the correspondence between Marjorie Courtenay-Latimer and J.B.L. Smith.
Coelacanth (Latimeria chalumnae ). arkive—Images of Life on Earth
http://www.arkive.org/species/GES/ﬁsh/Latimeria_chalumnae
In addition to some nice images, this site is remarkable for its video clips of a swimming coelacanth.
Coelacanth: The South African Institute of Aquatic Biodiversity (saiab)
http://www.saiab.ru.ac.za/coel.htm
The saiab, formerly known as the JLB Smith Institute of Ichthyology, promotes itself as “the Scientiﬁc
‘home’ of the Coelacanth” and oﬀers a variety of scientiﬁc papers and popular articles.
Latimeria chalumnae, Coelacanth. Digital Morphology.
http://www.digimorph.org/specimens/Latimeria_chalumnae/whole/
Part of nsf ’s “Digital Morphology” project, this site includes d and d visualizations of living and
extinct vertebrates and invertebrates.
Instructors using this case might consider buying a cast of a fossilized coelacanth to heighten the drama
during their case presentation. Casts are available for a reasonable price (around ) from commercial
Internet sites including:
http://www.sciencemall-usa.com/coelacanth.html
Note: Such commercial sites are mentioned purely for informational purposes and the reader’s
convenience and do not represent endorsement of any kind by the nccsts or its granting institutions.
Acknowledgements: This case study is based on work supported by the National Science Foundation under Grant
No.  as part of the nsf-funded Case Studies in Science Workshop held at the University at Buﬀalo, State
University of New York, on May –, . Any opinions, ﬁndings and conclusions or recommendations
expressed in this material are those of the author(s) and do not necessarily reﬂect the views of the National Science
Foundation.
Copyright ©  by the National Center for Case Study Teaching in Science.
Originally published // at http://www.sciencecases.org/strange_ﬁsh/strange_ﬁsh_notes.asp
Please see our usage guidelines, which outline our policy concerning permissible reproduction of this work.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Handout I
East London Museum
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Handout II
Birds
Mammals
To
Dinosaurs
Therapsid
Thecodont
DIAPSIDS
SYNAPSIDS
Labidosaurus
Reptile
Eryops
STEM REPTILES
Amphibian
Eusthenopteron
Cladoselache
Lobe Fin Fish
Shark
Climatius
Pteraspis
Spiny Shark
Jawless Fish
Drawn by Jim Stamos, Department of Biological Sciences,
University at Buﬀalo, , based on Dixon.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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Handout III
Image provided by Jensan Scientiﬁcs LLC/sciencemall-usa.com. Used with permission.
Photo © by Mark V Erdmann, Conservation International Indonesian Marine Program. Used with permission.
CASE TEACHING NOTES for “A Strange Fish Indeed” by Robert H. Grant
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