2. 102
Inventing ‘the four-legged fish’
during this period vertebrate palaeontologists deliberated on
the form and status of Ichthyostega in the history of evolution,
the image of a ‘four-legged fish’ settled in the public imagina-
tion to such a degree, that it shaped scientific lore about the
animal until the late 1990s.
1. Introduction
In September 2005 a new and long awaited reconstruction of
the Devonian tetrapod Ichthyostega appeared in Nature.2
The
reconstruction, proposed by palaeontologists Jennifer Clack,
Per Ahlberg and Henning Blom, was juxtaposed with another
published in 1996 by the Swedish palaeototlogist Erik Jarvik
(1907-1998) 3
[Fig. 1]. For more than 40 years Jarvik had
remained the international authority on Ichthyostega, main-
taining with only very minor revisions his reconstruction first
published in 1955 in the popular scientific journal American
Scientific4
[Fig. 2].
Fig. 1. Top: the new reconstruction of Ichtyostega according to Clack, Ahlberg
and Blom. Bottom: Jarviks reconstruction as depicted in Jarvik, 1996. Source:
Clack, et al., “The axial skeleton…” Nature, 2005.
2
Jennifer A. Clack, Per Ahlberg and Henning Blom, “The axial skeleton of the
Devonian tetrapod Ichthyostega”, Nature, 2005, 437:137-140.
3
Erik Jarvik, “The Devonian tetrapod Ichthyostega”, Fossils and Strata, 1996,
40:1-213.
4
E. Jarvik, “The earliest tetrapods and their fore-runners”, Scientific Monthly,
1955, 3:141-154
3. 103
Ries
Jarvik’s 1955 reconstruction was not his first attempt at visu-
alising Ichthyostega. An earlier version was published three
years before in the scientific journal Messages on Greenland5
[Fig. 3]. While this version did not boast a reconstruction
of the whole body skeleton, the general outline is still quite
similar to Jarvik’s 1955 version. Nevertheless, the difference in
the position of the hind limbs is quite striking. In this aspect,
the 1952 version, in fact, corresponds more closely with the
version proposed in Nature in 2005.
Fig. 2 Jarvik’s 1955 version of Ichthyostega. Source: Jarvik, “The earliest tetra-
pods…”, Scientific Monthly, 1955.
Jarvik wrote in 1952 that he had depicted the hind limb point-
ing backwards as it appeared in the fossils.6
But why then did
he twist it around in 1955? And how did Jarvik’s 1955 version,
originally conceived for a popular audience, become and remain
accepted as scientifically correct for more than 40 years? In the
following, some light will be shed on these questions.
5
Erik Jarvik, “On the fish-like tail in the ichthyostegid stegocephalians with de-
scriptions of a new stegocephalian and a new crossopterygian from the Upper
Devonian of East Greenland”, Meddelelser om Grønland, 1952, 114(12): 1-90.
6
Jarvik, “On the fish-like tail”, p. 21.
4. 104
Inventing ‘the four-legged fish’
2. Early vertebrates and international politics
The first fossils of Ichthyostega were found in 1931 by a group
of palaeontologists on the Danish Three-Year Expedition to
East Greenland 1931-34.7
In the decades between World War
I and World War II, East Greenland was the scene of intense
national rivalry between Denmark and Norway over the right
to sovereignty and scientific investigation. With ever-growing
intensity expeditions were dispatched with trappers, scientists
and national flags to mark the determination of the rivalling
nations in their engagement with the region. Geo-political
tension reached a climax in the summer of 1931, when a team
of Norwegian trappers raised the Norwegian flag over their
hut and claimed part of the coastline for Norway. Shortly
after, the Norwegian government acknowledged the claim,
whereupon the Danish government lodged a complaint with
the International Court in The Hague.
Fig. 3. Jarvik’s 1952 version of Ichtyostega. Source: Jarvik, “On the fish-like
tail…”, Medd. om Grønland, 1952.
7
In fact specimens had been collected by the Swedish geologist Oscar Kulling
already on Lauge Koch’s East Greenland expedition in 1929, but only later were
they recognised as tetrapods. See Erik Stensiö, “Upper Devonian Vertebrates
from East Greenland. Collected by the Danish Greenland Expeditions in 1929
and 1930. With 36 plates and 95 figures in the text”, Meddelelser om Grønland,
1931. 86/1: 1-213.
5. 105
Ries
Itwasinthisclimateofintensegeo-politicalrivalrythatDenmark
launched the Three Year Expedition to East Greenland 1931-
34 under the leadership of the Danish geologist Lauge Koch.
At the time Koch, having conducted geological investigations
in Northern and North-Eastern Greenland on numerous
expeditions in the 1910s and 1920s, was counted among the
top international experts on Greenland geology, enjoying the
confidence and unfailing support of the Danish Prime Minister,
Thorvald Stauning, as well as that of the Director of the Danish
Greenland Administration, Jens Daugaard-Jensen. 8
The Three-Year Expedition was the largest expedition that
hadeversetoutfromDenmark.Everysummerclosetoahundred
expedition members descended upon the East Greenland coast
to amass scientific results to be publicly announced via radio,
newspapers and internationally acclaimed scientific journals.
And it was on this expedition that in August 1931 a team of
geology students, all in their early twenties, went tracing the
slopes of Mount Celsius, Ymer Island, for fossil remains of
Devonian vertebrates. Leader of the team was Gunnar Säve-
Söderbergh of Uppsala University who, under the guidance of
Professor Erik Stensiö of the Swedish Natural History Museum
in Stockholm, had been studying the material collected on
previous Koch expeditions to the same locality.
Since Stensiö’s appointment as a professor at the museum
in 1923, the Section of Paleozoology had grown to become
an international centre for research in early vertebrates, and
students from all over the world were drawn to Stockholm to
work under Stensiö’s charismatic and undisputed leadership.9
In 1921, the publication of Stensiö’s doctoral thesis on Triassic
sharks and bony fishes from Spitsbergen had caused a revolu-
tion in early vertebrate palaeontology. Until the beginning of
the 20th
century, palaeozoic fishes had generally been described
as they presented themselves in the rock, and classified on the
basis of exo-skeletal anatomical features such as the scales or
8
For a fuller description of Lauge Koch’s career, see Christopher J. Ries, Retten,
magten og æren. Lauge Koch Sagen, (Copenhagen, Lindhardt og Ringhof), 2003,
and Christopher J. Ries, “Lauge Koch and the Mapping of North East Greenland:
Traditon and Modernity in Danish Arctic Research”, pp. 199-231 in Michael
Bravo and Sverker Sörlin eds., Narrating the Arctic. A Cultural History of Nordic
Scientific Practices (Canton: Science History Publications, 2002).
9
, Early vertebrates, 1996, (Oxford: Oxford University Press), on p. 316.
6. 106
Inventing ‘the four-legged fish’
the pattern of the dermal bones on the head. Stensiö, on the
other hand, made every effort to remove the rock around his
fossils, dissecting through them to reveal internal anatomi-
cal features.10
The success of Stensiös investigations largely
stemmed from his use of the method of grinding away thin
‘slices’ of fossils to reveal minute and otherwise inaccessible
internal anatomical structures in his specimens. Thus, it was
Stensiö who pioneered the modern way of looking at these
fossils as living animals.
It was therefore only natural that Koch, looking for experts
to handle the Devonian vertebrate fossil material from his
expeditions, turned to Stensiö for assistance. Stensiö, in return,
was always looking for means to maintain and to expand his
institute and scientific reputation, and was drawn to Koch for
the vast amount of material and the economic support offered
to him by the Danish state in the attempt to outshine the
Norwegian exploratory campaigns in East Greenland.
It was in this intensely competitive politico-scientific climate
that Säve-Söderbergh’s team in 1931 found seven fossil skulls
and some other fragments of a previously unknown type of
‘stegocephalian’ from the late Devonian period about 360
million years ago. Stegocephalia was a blanket term including
all pre-Jurassic amphibians: a large and heterogenous group
of four-legged intermediate stages between fishes and reptiles,
considered to predate the development of the major land-dwell-
ing animal groups of dinosaurs, reptiles, mammals and birds. A
trait common to these stegocephalians and their closest possi-
ble relatives among the fishes – the so-called ‘crossopterygians’
[Fig. 4] - was a thick dermal skull of ossified connective tissue
with openings for the eyes and nostrils. Comparing such skulls
was one of the ways that palaeontologists tried to clarify the
evolutionary relationships in the Devonian vertebrate fauna.
10
Colin Patterson, “Erik Helge Osvald Stensiö”, Biographical Memoirs of Fellows
of the Royal Society, 1990, 35: 363-380, p. 366.
7. 107
Ries
Fig. 4. The Devonian crossopterygian Holoptychius, as depicted in Säve-Söderberg,
1938, p. 150. Specimens of this species achieved a length of one to two metres.
When studying the relationships between different groups of
Devonian vertebrates it is useful to compare the system of lateral
lines with which fishes sense movements, currents and pressure
in the water. Since these lines penetrate and embed themselves
in the dermal bones of the skull, it is possible to identify those
dermal bones of different species, which contain similar parts
of the line system. Among closely related forms the dermal
bones and line patterns of the skull were similar in number and
pattern, but before Säve-Söderbergh’s discovery, this method
could not be used to compare fishes and early tetrapods.
Until then, the oldest known stegocephalians were of
Carboniferous origin – about 310 million years old – and
even if these did show grooves for lateral lines in their dermal
skulls, it was difficult to assess the relationship between these
grooves and the deeper-lying canals in the fishes. In other
words, investigations of Carboniferous stegocephalians hinted
at some form of kinship with the fishes, but they also revealed
a considerable evolutionary gap between the two groups.11
The
Devonian tetrapod found by Säve-Söderbergh in 1931 was,
therefore, extremely important from a scientific point of view,
and upon his return from Greenland that autumn Koch invited
Stensiö to witness the unpacking of the sensational fossils.
But the new material was also of political importance to
Denmark in view of the forthcoming trial at the International
Court in The Hague in the summer of 1932, of which Stensiö
was well aware. In March 1932 he wrote to Koch: “The stego-
cephalian material is simply wonderful. As far as I can see,
11
Gunnar Säve-Söderbergh, “På jagt efter Østgrønlands fortidsdyr”, pp. 142-
157 in Gunnar Thorson ed., Med Treaars Ekspeditionen til Chr. X’s Land,
(Copenhagen: Gyldendal, 1937) pp. 148-49.
8. 108
Inventing ‘the four-legged fish’
Säve-Söderbergh will not be able to finish a full treatise in time,
but he will certainly publish a good preliminary description,
to make it clear that the merit and honour of this discovery,
so very important to palaeontology, belongs to Denmark.”12
Koch, on the other hand, was more cautious, and worried that
premature publication of the sensational material might cause
more harm than good. “I am especially concerned,” he wrote
to Stensiö, “that a number of Norwegian vessels will probably
be laid up and rather inexpensively for hire this summer. If
such a publication is out by July 1st
, a smart American tourist
could easily pursue the greatest dream of many tourists, which
is to become the leader of ‘a real scientific Polar expedition’,
and start poaching on our reserves.”13
While Koch agreed that
a forthcoming treatise on the Devonian stegocephalians should
be announced at the preliminary court hearings in the summer
of 1932, an actual publication would have to wait. Hopefully,
another summer alone in the field would give Säve-Söderbergh
enough of a head start to discourage foreign competition and
leave the Devonian tetrapods securely in the hands of Koch,
Stensiö and their collaborators.
3. It’s alive!
And so it was that while, in July 1932, the Danish and
Norwegian delegations were busy discussing in court, Säve-
Söderbergh and a team of Swedish assistants revisited Mount
Celsius looking for more Devonian vertebrates. When the
expedition returned to Copenhagen on September 18th
1932,
Säve-Söderbergh’s ‘preliminary investigation’ of the Devonian
stegocephalians had not yet been published. But it was close to
completion, so Koch decided to let the cat out of the bag, and
in the weeks that followed, his success was celebrated in news-
papers around the world. “Dr. Lauge Koch” wrote the New
York Times, “veteran Arctic explorer, today returned from
Greenland with the announcement that he had found evidence
of one of the missing links in the chain of evolution – a four-
legged fish that walked ashore (...) The stegocephali, he says,
12
Stensiö to Koch, 7/3-32, LK/13.
13
Koch to Stensiö, 21/3-32, LK/13.
9. 109
Ries
were creatures with four legs. Halfway between fish and toads
in the evolutionary scale [...] This remarkable quadruped could
walk on land as well as live in the sea.”14
Considering the fact
that only some skulls had been identified at this time, Koch’s
statement was perhaps rather bold, but as an eye-catcher for
the general public, it was very much to the point.
In Nordwestdeutsche Zeitung Stensiö announced that the
four-legged fish matched the Jurassic lizard-bird Archaeopteryx
in scientific importance15
, while Koch called the discovery of
the creature ‘the greatest achievement of his expedition’.16
And
clearly, while he also reported on newly found deposits of lead,
zinc and silver, it was the tetrapod that got all the attention. Koch
was probably not far off the point in assuming that the price
of the specimens, if sold to a museum, would cover the whole
expenditure for the Three Year Expedition.17
On September
20th
, Koch received a letter from New York University with a
bid on any number of specimens that might be for sale.18
To most scientists, of course, a Devonian tetrapod meant
yet another piece in the puzzle of evolution. But the scarcity
of information available along with extensive media coverage
allowed for a wide range of ‘non-professional’ interpretations
of the animal. On September 22nd
, Charles Schuchert of the
Peabody Museum of Natural History in Connecticut, Ohio,
reported to Koch of the public interest in his latest discovery:
My dear Lauge Koch. All hail to the most heralded man of
science in Denmark and Greenland! We see your name on the
front pages of our daily papers, and your portrait inside, hear
your name over our radio, and find cartoons about you on the
editorial page of our New York Tribune. […] Fish stories every
man loves to hear [...] and Lauge Koch has the most wonderful
14
“Legged-fish fossils by thousands found on Greenland shore”, New York
Times, 19/9-32.
15
For an interesting parallel to the present article regarding Archaeopteryx and
the evolution of birds, see Christopher Jacob Ries, “Creating the Proavis: bird
origins in the art and science of Gerhard Heilmann 1913-1926”, Archives of
Natural History, 2007, 34, 1: 1-18.
16
“Wichtige Ergebnisse der dänischen Ostgrönlandsexpedition”,
Nordwestdeutsche Zeitung, 25/9-32.
17
“Legged-fish fossils”, New York Times, 19/9-32.
18
Free to Koch, 20/9-32, SASO, Correspondence K-N.
10. 110
Inventing ‘the four-legged fish’
of them all. Professor Gregory of the American Museum ap-
parently does not believe you have a Devonian Stegocephalia,
and last Sunday the editor of the New York Times discussed
your find, but I swear by Lauge Koch and his fish with legs.
Hoch soll er leben! Yours truly, Charles Schuchert.19
All things taken into account, ‘the four-legged fish’ was
already widely known when the first scientific article in its
honour – Säve-Söderbergh’s ‘Preliminary note on Devonian
Stegocephalians from East Greenland’ – was published in
mid-November (Säve-Söderbergh, 1932) [Fig. 5]. Letters of
interest and congratula-
tion began to arrive in
Uppsala, Stockholm
and Copenhagen. In
late December, Stensiö
reported to Koch of the
considerable enthusiasm
and expectation with
which the news had been
received among palae-
ontologists, zoologists
and geologists all over
Europe, from Hungary
to Great Britain.20
The
potential of the mate-
rial was further increased
when in East Greenland
during the summer of
1933, Säve-Söderbergh
found a fossilized skull
of a hitherto unknown
type of Devonian lungfish, showing marked similarities with
crossopterygians as well as stegocephalians.
That summer, Denmark had won the case against Norway
in The Hague, and the general concept of ‘the four-legged fish’
– having figured as a scientific trump for Denmark – was, as
Koch later explained to Säve-Söderbergh, “lifted to a level, that
19
Schuchert to Koch, 22/99-32, SASO, Correspondence K-N.
20
Stensiö to Koch, 28/12-32, LK/14.
Fig. 5. Skull of Ichthyostega as depicted in
Säve-Söderberg, 1932, p. 42.
11. 111
Ries
must naturally make an impression on any government.”21
In
January 1934, as preliminary investigations of the new mate-
rial began, Koch was able to announce publicly the find of
a completely new path leading from the fishes to the higher
animal classes:
A completely new four-legged fish has been found! In ‘old
fourlegs’ we believed to have found a missing link between the
lungfish and the tetrapods, which was epoch-making. But now
it looks as though we have found a new path leading from the
lungfishes up to ... well, this new thing! Therein lies a discov-
ery of extraordinary importance for our whole investigation of
the origin and development of life on Earth ... Therefore these
investigations are supervised with all the carefulness that the
outstanding professionals in Stockholm have developed in their
difficult craft. No possibility will escape their keen eyes.22
‘The four-legged fish’ was by now a full-blown media star, and
while Swedish newspapers reported of foreign scientists flocking
to Stockholm, Koch used the sensation to further the interest of
private investors, government officials and the general public.
Not all, however, were equally impressed with Koch’s
sensationalist presentation of the material. When in March
1934 Säve-Söderbergh was invited to talk about his investiga-
tions to the Danish Geological Society, Koch gave an introduc-
tory speech, which, as one observer remarked in a letter to a
colleague, “was quite funny in a way, because he in all naked-
ness told us about all the rubbish he made people believe about
the four-legged fish: ‘I usually equip it with four limbs and all
imaginable fins, gills, lungs and everything; in Stockholm they
all thought it was a scream; we had a great party up there, and
so on´. Some were scandalized at his frank confessions, and
despite the humorous tone in his speech, the atmosphere was
strangely tense when he finished.”23
All in all, according to the
same observer, the evening was a limited success: “Säve’s talk
was sort of good, as it actually contained some new informa-
tion, but most people lacked the qualifications to understand
21
Koch to Säve-Söderbergh, 6/4-36, SASO, Correspondence K-N.
22
“Lauge Koch har hjemført ukendt hvirveldyr”, Politiken, 21/1-34.
23
Milthers to Noe-Nygaard, 28/3-34, NN, Correspondence 1926-39.
12. 112
Inventing ‘the four-legged fish’
him and as he spoke very dryly, listing an eternity of names, the
overall effect was quite deadening.”24
Säve-Söderbergh might well have left most of the audience
in a befuddled haze, speaking as he did of a complete revolution
in the conception of early vertebrate evolution, bridging the
troublesome gap between the fishes and the amphibians. He was
convinced that the Devonian crossopterygians (or lobe-finned
fishes), lungfishes and tetrapods had so much in common, that
they had to be classified together in an entirely new sub-group
among jawed fishes. It was this group of creatures – named the
‘choanates’ after their internal nostril openings or ‘choanae’
– that had given rise to the amphibians, the reptiles, the birds,
the mammals and ultimately to humankind.25
To be sure, Koch, not being a specialist, might have been
taking a few liberties when celebrating the work going on in
Stockholm and Uppsala, but notes that he made for public
speeches, which are kept in his personal archives, do reveal
his undisputable knack for conveying the problem to a general
audience. To a high-school audience he said the following:
Let us imagine a large and widely branching tree buried during
a sandstorm, with only a few twigs showing above the ground.
This is roughly how we must view the animal world of today.
And to understand relationships, we must scrape away the
sand, to find out how the twigs join in larger branches and
ultimately meet in the trunk itself [...] Collecting in Greenland,
we are working in the place where the amphibian-branch and
the fish-branch start to meet, that place in the history of evolu-
tion, where the vertebrates first went on land and acquired
legs. But here comes the surprise: the Greenland investigations
have shown, we are not looking at just one family tree, but at
no less than three [...] It has turned out, that what used to be
seen as related, is in fact branches of the three trees tangled
together [...] The amphibians, which we used to perceive as
one big branch of the big family tree, do in fact belong to three
different family trees.26
24
Milthers to Noe-Nygaard, 28/3-34, NN, Correspondence 1926-39.
25
Säve-Söderbergh to Koch, 1/1-33, LK/14.
26
Manuscript for a speech given to high-school students, undated [between 1933
and 1938], LK/14.
13. 113
Ries
Fig. 6. Diagram showing the relationships of early vertebrates and stegocphalians
according to Säve-Söderbergh. From Säve-Söderbergh, 1938, p. 151. Translation
of central concepts from the bottom up: gnathostomer = jawed fishes; fisk =
fishes; hajlignende former = shark-like forms; aktinopterygier = true fishes; lunge-
fisk = lungfishes; padder = amphibians; halepadder = urodeles; haleløse padder =
tail-less amphibians; pattedyr = mammals; krybdyr = reptiles; fugle = birds.
What Koch was explaining here in relation to the amphibians
was the notion of ‘polyphyletism’, which became a controver-
sial ‘leitmotiv’ in the writings of members of the Stockholm
School of early vertebrate palaeontology. Proponents of ‘poly-
phyletism’ – in opposition to proponents of the more gener-
ally accepted theory of ‘monophyletism’ – worked from the
assumption that some of the derived traits shared by extant
taxa have appeared separately several times. Accordingly,
Säve-Söderbergh was quite convinced that the choanates had
developed along at least two parallel lines of evolution: one
leading to the lungfishes and the urodeles (salamanders and
newts) and another leading to the lobe-finned fishes and all
14. 114
Inventing ‘the four-legged fish’
other tetrapods, even allowing for a possible further division of
the tetrapods into still more lines of evolution27
[Fig. 6].
But a complete rearrangement of the system of classifica-
tion in the fish-tetrapod transition was a complicated project.
It required not only the comparison of available Devonian
vertebrate material to develop a reliable terminology of bones
and sensory canals in the skulls of different species, but also
further investigations of already known related faunas in order
to establish a firm foundation for discussion of specific devel-
opments in the fish-tetrapod transition. So, while Koch was
showing off his evolutionary sensation to politicians, patrons
and the general public, Säve-Söderbergh devoted himself to
stratigraphical analysis and description of other Devonian
and Triassic vertebrates. He did participate in Koch’s East
Greenland expeditions in 1934 and 1936, collecting much new
material, but he did not add any significant comments on the
Devonian tetrapods, limiting himself to brief references in a
number of publications.28
Still, the sensational and transitional nature of the animal
had been publicised with enough success to keep the image of
‘the four-legged fish’ on its feet, so to speak, even without the
justification of continuous scientific elaboration in the labora-
tory. In 1935 some of the most spectacular specimens were
conspicuously displayed in the ‘Greenland wing’ of the Danish
stand at the Brussels World Fair.29
In December 1935 Koch became involved in a bitter conflict
with eleven of the most prominent Danish geologists of the day,
among them O. B. Bøggild, director of the Danish Geological
27
Gunnar Säve-Söderbergh, “Some points of view concerning the evolution of
the vertebrates and the classification of this group”, Arkiv för Zoologi, 1934.
26a/17: 1-20.
28
Gunnar Säve-Söderbergh, “Further contributions to the Devonian stratigra-
phy of East Greenland, 2. Investigations on Gauss Peninsula during the summer
of 1933. With an appendix: Notes on the geology of the Passage Hills (East
Greenland)”, Meddelelser om Grønland, 1934, 96/2: 1-74; Gunnar Säve-
Söderbergh, “On the dermal bones of the head in labyrinthodont stegocephal-
ians and primitive Reptilia with special reference to Eotriassic stegocephalians of
East Greenland”, Meddelelser om Grønland, 1935, 98/3: 1-211; Gunnar Säve-
Söderbergh, “On the morphology of Triassic stegocephalians from Spitsbergen
and the interpretation of the endocranium in the Labyrithodontia”, Kungliga
Svenska Vetenskapsakademiens Handlingar, 1936, 3/15: 1-181.
29
Koch to Stensiö, 18/1-35, LK/16.
15. 115
Ries
Museum and the only professor of geology in Denmark, and
Victor Madsen, head of the Geological Survey of Denmark.
The immediate reason for this controversy was a book review
submitted to the Bulletin of the Geological Society of Denmark
by ‘the 11’, as Koch’s attackers was soon dubbed by the press.30
The book in concern was Lauge Koch’s Geologie von Grönland,
published in September 1935 in the German handbook series
Geologie der Erde.31
, and the fierceness of the critique dealt
out by Koch’s Danish colleagues was remarkable.
Over fifteen pages, not only Koch’s recent book but also
his general scientific conduct and achievements throughout
his career were met with serious accusations under headings
such as: “Misunderstandings and Statements that have not
been Proved”, “Misleading Argumentation”, “Suppressions
and Incorrect Quotations”, “Appropriation of the Results of
other Explorers” and “Absurdities and Self-Contradictions”.
The review was followed by a call for an extraordinary general
assembly of the Geological Society of Denmark, at which a
resolution in effect excluding Koch from the society would be
presented. Furthermore, 600 off-prints of the review in English
were distributed to geologists throughout the world.
Considering the prominence of the attackers, and the
fact that they counted among them former teachers as well
as students of Koch, this critique was not to be taken lightly.
After having conferred with the Director of the Greenland
Administration Jens Daugaard-Jensen, Koch decided to sue
his attackers for slander. The press quickly took advantage of
what would become the largest public scandal in the history
of Danish science and one of the most extensively documented
Danish verdicts on any subject known until then. Over the next
three years, “the Lauge Koch Case” haunted Danish newspa-
per headlines as it moved through the Danish court system,
until in June 1938, when it ended with a verdict that let both
parties boast of victory. This is not the place to deal with the
consequences of this painful conflict in detail. Suffice it to say
30
O. B. Bøggild, K. Callisen et al., “Remarks upon ‘Lauge Koch: Geologie von
Grönland, 1935’, in Meddelelser fra Dansk Geologisk Forening, 8(5), 1935, pp.
497-512.
31
Lauge Koch: “Geologie von Grönland”, in E. Krenkel (ed.), Geologie der Erde,
Berlin: Gebrüder Bornträger, 1935.
16. 116
Inventing ‘the four-legged fish’
that an insurmountable barrier had been established between
Koch and the geologists at the Danish Geological Museum,
which prevented any form of cooperation between the parties
for the rest of Koch’s life.32
To suggest that this painful situation was caused by one
single book review alone would of course be absurd. Rather, the
‘Lauge Koch Case’ must be seen as an articulation of dramatic
upheavals in the culture of Danish arctic geology in a period
of economic crisis and serious geopolitical tension. For almost
half a century the Geological Museum of Copenhagen had been
the natural institutional centre of Danish geology, receiving
all-important collections made on Danish expeditions for safe
keeping, investigation and exchange with museums and collec-
tions abroad. But from 1930 onwards, Koch, as the leader of
the Danish East Greenland expeditions, had introduced a new
order, taking all collections from his expeditions to a warehouse
in the harbour of Copenhagen. From there he distributed the
material directly to international specialists abroad, refusing
repeated requests by the Geological Museum of Copenhagen
to have the material handed over. Koch, enjoying considerable
support from politicians, government officials and wealthy
businessmen with an interest in Denmark’s arctic possessions,
had been able to refuse such claims with reference to the lack of
necessary scientific expertise available in Denmark. In summa-
ry, then, Koch’s success and internationalism had seriously
undermined the position of the Danish Geological Museum in
Greenland geology, both in Denmark and abroad.
After the debacle in 1935, however, Koch’s position was
increasingly challenged. The controversies between Koch and
his professional colleagues in Denmark seriously marred his
credibility and reputation – in Denmark much more so than
abroad. Simultaneously, the Danish victory in The Hague in
1933 had lifted the sense of political urgency formerly attributed
to Koch’s activities. When Jens Daugaard-Jensen, the Director
of the Greenland Administration died in November 1938,
Koch lost one of his most fierce and faithful political allies.
Koch still maintained his position as independent consultant
32
For a fuller treatment of this controversy and its consequenses, see Ries,
“Retten”, and Ries, “Lauge Koch”, 2002.
17. 117
Ries
for the Greenland Administration, but Danish claims to Koch’s
East Greenland material intensified.
4. Suspended animation
In 1937, the twenty-six year old Säve-Söderbergh was appoint-
ed professor of palaeontology at Uppsala University. But he
was also struck by a serious lung disease, which kept him in
bed for months and years on end, and seriously impeded his
work. This, and the outbreak of World War II, which brought
Koch’s Greenland expeditions to a complete halt between 1939
and 1947, prevented further progress in the investigation of the
Ichthyostega material. Up to and during World War II, Säve-
Söderbergh, writing from his sickbed, and others referred to
the East Greenland material in scientific textbooks and popular
books and journals. General interest in the whole fish-tetrapod
transition matter was boosted by the 1938 catch off the South
African Coast of the extant lobe-finned coelacanth Latimeria,
a ‘living fossil’ thought to have been extinct for at least 70
million years. But owing to the limited mass of scientifically
certified knowledge about Ichthyostega, most commentators
limited themselves to descriptions of the skull and general
considerations of the fish-tetrapod transition on the basis of
other available material.33
During World War II, while Säve-Söderbergh was struggling
through serious illness and surgical operations removing part
of his rib cage, Koch was struggling to gain momentum after
serious setbacks caused by the war, and by bitter rivalry within
the Danish geological community itself. In 1939, the Danish
Government decided that all vertebrate collections from
Lauge Koch’s expeditions were to be transferred to the Danish
33
See e.g. Säve-Söderbergh, “På jagt”, 1937; Gunnar Säve-Söderbergh, “Drag
ur den svenska vertebratpaleontologins utveckling och resultat”, Geologiska
Föreningens i Stockholm Förhandlingar, 1946, 68: 352-371; Gerhard Heilmann,
Universet og Traditionen, (Copenhagen, Munksgaard, 1940); Eigil Nielsen,
“’Den firbenede fisk’ og andre hvirveldyr fra Østgrønlands fortid”, Dyr i Natur
og Museum. Årbog for Universitetets zoologiske museum, 1943: 63-76; Johannes
V. Jensen: “Amfibiet. Haletudsen og den firbenede fisk”, Arbejdernes Almanak,
1945: 25-30, Alfred S. Romer, Vertebrate Paleontology, (Chicago: University of
Chigaco Press, 1933, 2nd
edition, 1945).
18. 118
Inventing ‘the four-legged fish’
Zoological Museum, in an attempt to satisfy Danish claims
to the material while at the same time respecting Koch’s and
Stensiö’s refusal to have anything to do with the Danish geolo-
gists. Still, a special arrangement was made for the Devonian
stegocephalians, which remained in Sweden under the custody
of Säve-Söderbergh and Stensiö.
There were at least two reasons for this. For one, Koch’s
Swedish collaborators were appalled at the way Koch had been
attacked by his Danish colleagues, but perhaps more to the
point, the only Dane remotely qualified for working on the
material was young student Eigil Nielsen, who had been hand-
picked by Koch for specialized training under Stensiö. Nielsen
had still not completed his education, and was currently occu-
pied by studies of the vast collections of Triassic fishes brought
home by Koch’s expeditions.34
In 1942 Koch’s most influential patron, the Danish prime-
minister Thorvald Stauning, died. Koch’s office was moved to
a location outside the Greenland Administration building itself.
The following year the palaeontological collections delivered to
the Zoological Museum in 1939 were moved to the Geological
Museum, where Koch’s opponents had consolidated themselves
in a tightly knit and very influential lobby, aiming to set the
agenda for future Danish geological investigations in Greenland.
But still, the Devonian stegocephalians remained in Stockholm.
Curiously, as World War II came to an end, Koch’s position
at the fringes of the politico-scientific arena in Denmark began
to work in his favour. At the time, Daugaard-Jensen’s successor
as director of the Greenland administration, Knud Oldendow,
was struggling with depression and physical illness under the
burden of his new authority and the challenges of re-ordering
the arctic scientific community after years of bitter conflict.
According to Koch, Oldendow often came to the sanctuary of
Koch’s office for comfort and advice.35
In May 1945 the German occupation of Denmark was
lifted, and in July Koch’s opponents at the Geological Museum
launched a small expedition to Nugssuaq in West Greenland.
They also proposed to Oldendow the establishment of a
Greenland Geological Survey proper – deliberately and specifi-
34
Ries “Retten”, 2003, pp. 318-29.
35
Koch to Porsild, 18/6-45, RMOG/2.
19. 119
Ries
cally leaving Koch out of the picture. In the same month Koch
decided to visit his colleagues in Stockholm to sketch out plans
for the future. Oldendow decided to join him. According to
Koch, the trip became a mixture of recreation and of discus-
sion of future cooperative expeditions, and Oldendow, “who
conceives of himself as a sort of amateur-ornithologist and
therefore makes claim to certain scientific qualifications, took
particular interest in the display of the four-legged fish.”36
To say that Ichthyostega alone swung Oldendow’s favour in
Koch’s direction would clearly be an exaggeration, but the
director must surely have been convinced of the importance
of the unique the material. Likewise, we may assume, that
Koch, Säve-Söderbergh and Stensiö in their discussions with
Oldendow reiterated their complete refusal to cooperate with
the poorly qualified geologists in Denmark.
Oldendow,meanwhile,decidedtocompromisebetweenKoch
and his adversaries. In January 1946 he approved the establish-
ment of the Greenland Geological Survey (GGU for Grønlands
Geologiske Undersøgelser) as suggested by the museum geolo-
gists, while at the same time agreeing to financially support
Koch’s initiative to resume his activities in East Greenland.
Protests from the Danish geologists proved fruitless, and thus
emerged a peculiar arrangement: for the next twenty-two years,
two state-subsidised Geological Surveys operated independently
in Greenland – Koch in the East, and the GGU in the West.37
Very little exchange or cooperation took place between the
two, and the investigation and publication of findings concern-
ing the East Greenland Devonian vertebrates remained on the
hands of Koch and his co-operators in Sweden.
Koch’s international reputation and political skills had
secured his continued existence as a leader in Danish Greenland
geology after World War II, but the steady, unquestioned and
undivided governmental support that he had enjoyed before
the war, was lost. He now had to compete for funds with the
GGU on a yearly basis. Now, more than ever, he was in need
36
Ibid.
37
Very little has been published describing the peculiar situation within Danish
Greenland geology during the Cold War period. One exception is Knud Ellitsgaard-
Rasmussen, “En stjerne fødes – beretning om GGU’s tilblivelse”, GEUS Report,
1996, 102:1-76.
20. 120
Inventing ‘the four-legged fish’
of scientific sensations and of public attention to muster the
continued support for his East Greenland activities.
Koch’s first expedition after World War II was launched in
1947. Finding people to continue the collecting of vertebrates
had to be sorted out. Säve-Söderbergh, despite a slight recovery
that had actually allowed him to leave the hospital in 1945,38
was still too weak for long travels, let alone for working in the
field. Only two other people could be considered for the job:
Eigil Nielsen and Erik Jarvik, both of whom had studied in
Stockholm under Stensiö and had served as field assistants for
Säve-Söderbergh before the war.
In 1942 Nielsen had defended his doctoral thesis on “Triassic
fishes from East Greenland”. Stensiö, who had been on the
examining committee, had high regard for Nielsen’s work,
and according to him, the day had been a celebration for all
parties involved.39
Jarvik had defended his doctoral thesis that
same year. His work on the fossil lobe-finned (crossopterygian)
fishes, which were already regarded as the possible ancestors
of tetrapods, suggested that while one group of these 370-
400-million-year-old fishes (the Porolepiformes) shared the
same snout structure as the urodeles (salamanders and newts),
another (the Osteolepiformes) shared unique snout features
with other tetrapods (frogs and amniotes). The implications
were clear. The tetrapods had evolved at least twice from differ-
ent fish groups. To Säve-Söderbergh, who had been on Jarvik’s
thesis examining committee, the thesis “provided the theory of
a polyphyletic origin of the amphibians with a new and particu-
larly beautiful confirmation and a much firmer foundation.”40
Both Nielsen and Jarvik joined Koch’s expedition for further
collections in the summer of 1947. But still there was the ques-
tion of the future of the four-legged fish. Säve-Söderbergh had
not added anything of significance to its investigation since
1932, and Koch was getting anxious for something to happen.
In Denmark, interest in the material was on the rise, and on
the issue of funding, Koch was quite optimistic. In September
1947 he wrote to Stensiö: “I believe that the state will donate
38
Säve-Söderbergh to Stensiö, 6/8-45, SASO, Correspondance O-S.
39
Erik Stensiö, autobiography (unpublished manuscript, 91 pages, 1980), Library
in the Section of paleozoology Riksmuseet, Stockholm, on p. 63.
40
Säve-Söderbergh, “Drag ur “, (1946).
21. 121
Ries
large grants regarding the East Greenland material, which has
been so well advertised over the years.“41
Koch’s greatest worry
was that Säve-Söderbergh’s protracted illness was a stumbling
block to achieving the quick results so much in demand. That
autumn, the whole issue gained in urgency, as Nielsen, consort-
ing with the Danish journalist Ebbe Munck, aired some rather
frivolous plans about collecting and selling fossils in an attempt
to raise money for an East Greenland expedition of his own. In
September 1947 Koch wrote to Stensiö as follows:
[Eigil Nielsen] counts on being able to find about three pieces
in one summer season. These should then be sold to the Carn-
egie Foundation for 20.000 Dollars, for which Munck would
buy rice to be sold in Denmark. From this you may gather, that
I would very much like to continue the collection of vertebrates
on my future expeditions, and that I find it quite unacceptable
that Denmark should begin to sell any of these stegocephalians
before they are properly investigated.42
It was one thing, Koch seemed to reason, to use the precious
fossils for P.R. purposes to influence state officials and possible
private benefactors. It was an entirely different matter to trade
them to foreigners, encroaching on the otherwise exclusive access
to the material enjoyed by Koch and the Stockholm school.
Nielsen, who was now employed at the Geological Museum
in Copenhagen, may not have been showing himself as the most
dependable of Koch’s collaborators, but he was capable, ambi-
tious and keen on taking over the Devonian stegocephalians
from Säve-Söderbergh, should he not show some recovery in
the near future.43
With demands and financial prospects on the
rise and Säve-Söderbergh on stand-by, only Stensiö and Jarvik
were active in Sweden, and Nielsen was an asset they could
hardly afford to neglect. Koch, therefore, was eager to keep
him on board, and to give the investigation of material related
to the Devonian fish-tetrapod transition priority over all other
tasks. He wrote to Stensiö as follows:
41
Koch to Stensiö, 30/9-47, LK/9.
42
Koch to Stensiö, 13/9-47, LK/9.
43
Koch to Stensiö, 13/9-47, LK/9.
22. 122
Inventing ‘the four-legged fish’
The crossopterygians are in good hands with Jarvik. But the
question remains what to do with all the material held by Säve-
Söderbergh. Of course we should not deprive him of his mate-
rial right away, but on the other hand the years keep passing,
without him getting any work done. One and a half year ago I
visited him during a good period, and at that time he was very
interested in Triassic stegocephalians of which he has quite a
lot of specimens. Furthermore he is keeping the lungfish and
the Devonian stegocephalians, and sooner or later the moment
will come, when he will have to let go of these things. I will
then suggest, that you [Stensiö] take over the lungfish, while
Nielsen takes over the Devonian stegocephalians […] Before
long, I hope to be able to raise money for continued collecting,
and what worries me the most, is the prospect of having the
funds, but not the necessary crew.44
Apparently, however, the idea of Nielsen taking over the
Devonian tetrapods did not go down well in Sweden. When
finally Säve-Söderbergh succumbed to his illness and died in
June 1948, negotiations between Koch and Stensiö resulted
in the decision that Nielsen should stick to his Triassic fishes.
The Ichthyostega material was to be kept in Stockholm on
‘stand-by’ for Jarvik to take on, when he had finished his
study of the crossopterygians.45
That summer, Jarvik joined Koch’s expedition on Mount
Celsius. Among the specimens collected that year were two
blocks containing the first known parts of the post-cranial
skeleton of Ichthyostega. Work carried out back in Stockholm
revealed, in one block, a tail and a well-preserved hind limb,
and in the other, parts of the head, trunk and forelimb. The
new material immediately aroused the interest of international
scientists, and Koch set out to exploit the situation to his own
advantage. In December 1948 he wrote to Stensiö:
I have informed the Danish Government, that two American
palaeontologists have seen our collections in Stockholm this
autumn, and that they have taken a great interest in them. I
therefore said to our Prime Minister: “Preferably, we should
44
Koch to Stensiö, 30/9-47, LK/9.
45
Koch to Stensiö, 8/7-48, LK/9.
23. 123
Ries
continue our collecting of vertebrates to keep the Americans
out of East Greenland.” He agreed with me on this.46
Having also presented the Prime Minister with that year’s find
of some promising lead deposits near Mesters Vig, Koch had
high hopes for consistent state support for his own expeditions
in the future. Denmark was, then even more so than now, a
country of limited natural resources, and the prospects of a
possible lead-mining facility in Mesters Vig was as strong a
card as any to be played in the game for government support,
at a time when national economies across Europe were strug-
gling to recover from the effects of war.
Over the next few years, the Mesters Vig lead earned Koch
steady governmental support for continued expeditions. But
Koch felt the urgent need for further investigations of the
Devonian vertebrate material. Nielsen was getting increasingly
involved with Koch’s adversaries at the Geological Museum,
who repeatedly declared that since the Devonian tetrapods had
been found on a Danish expedition, they belonged in a Danish
Museum, and should be worked on by a Danish scientist, more
specifically by Nielsen. Koch must have feared that the mate-
rial would slip from his hands while he was waiting for Jarvik
to get ready. In January he wrote to Stensiö, urging him to take
up the study of the tetrapods himself, while buying time with
the Danish geologists by offering them a couple of casts for
exhibition purposes.47
5. The twist of a limb
In June 1949 Koch announced on Danish Radio that a scientific
sensation was to be expected from ongoing Swedish investiga-
tions of ‘the four-legged fish’. But Stensiö never took on the
material. Apparently, he was determined that the tetrapods
should go to Jarvik. He, on the other hand, was busy completing
his crossopterygian studies, while competing, unsuccessfully as
it turned out, for the professorship in Historical Geology that
46
Koch to Stensiö, 2/12-48, LK/7.
47
Koch to Stensiö, 26/1-49, LK/9.
24. 124
Inventing ‘the four-legged fish’
had opened at Uppsala with the death of Säve-Söderbergh.48
In
1949 and 1950 Jarvik abstained from fieldwork to concentrate
on completing his thesis. Gunnar Wängsjö, another of Stensiö’s
disciples, took his place on Koch’s expeditions, making further
additions to the collection of postcranial Ichthyostega material.
In 1950 Jarvik’s crossopterygian studies were finally published.49
Koch and the stegocephalians could not be put off any longer,
and in February 1951 Jarvik declared himself ready to pick up
where Säve-Soderbergh had left off nineteen years before.50
The manuscript for Jarvik’s first article on the Devonian
stegocephalians was submitted in time to allow him to join
Koch’s East Greenland expedition in the summer of 1951. The
actual publication, however, appeared only in February 1952,
presenting a discussion of a range of Devonian vertebrate
fossils, including fishes, crossopterygians, lungfish and all
the available Ichthyostega specimens.51
Among the described
specimens was a single skull of a different type of Devonian
tetrapod found by Jarvik and Säve-Söderbergh back in 1933.
Most likely, it was this specimen to which Koch had referred
in the newspapers back in 1934, when he announced the
discovery of ‘a completely new four-legged fish’, but since then,
neither Säve-Söderbergh nor Jarvik had published anything on
it. Jarvik described the fossilized fragment as a separate species
of tetrapod and named it Acanthostega, but with only one
specimen to go on, he could not take his investigations any
further. Acanthostega went back to its drawer, staying there for
more than 30 years, until Jennifer Clack began investigating the
creature on the basis of new and exceptionally well-preserved
material recovered by her on Celcius Bjerg in 1987.
48
Stensiö, autobiography, pp. 67-68.
49
Erik Jarvik, “Middle Devonian vertebrates from Canning Land and Wegeners
Halvø (East Greenland). 2. Crossopterygii”, Meddelelser om Grønland, 1950,
96/4: 1-132; Erik Jarvik, “Note on Middle Devonian crossopterygians from the
eastern part of Gauss Halvø, East Greenland. With an appendix: An attempt at a
correlation of the Upper Old Red Sandstone of East Greenland with the marine
sequence”, Meddelelser on Grønland, 1950, 149/6.1-132.
50
Jarvik to Koch, 12/2-51, LK/7.
51
Erik Jarvik, “On the fish-like tail in the ichthyostegid stegocephalians with
descriptions of a new stegocephalian and a new crossopterygian from the Upper
Devonian of East Greenland”, Meddelelser om Grønland, 1952,114(12): 1-90.
25. 125
Ries
Back in 1952, however, Ichthyostega was still the only well
documented Devonian tetrapod, and Jarvik, on the basis of his
investigations, was able to confirm the status of Ichthyostega
as older and more closely related to the fishes than any other
known tetrapods:
As evidenced by the size and shape of the skull, the shoulder
girdle, the ribs and the pelvic bone, the animal was compara-
tively high and narrow – probably at least 1,25 times as high as
broad in the pelvic region – and on the whole fairly fish-like.52
Still, conspicuous features of the tail and parts of the vertebral
column caused Jarvik to classify the Ichthyostegids as ‘true
tetrapods’, well adapted to terrestrial life. Jarvik observed that
there were no fin-rays on the lower side of the tail “which no
doubt rested or dragged on the ground when the animal was
on land or in shallow water…[which] renders it likely that the
fin-rays in this part were reduced and disappeared in connec-
tion with the change from water life to an amphibious mode of
life.”53
Similarly, Jarvik noted, “as in other tetrapods in which
the body is carried mainly by the two pairs of legs, the vertebral
column and the back of the animal are more convex in lateral
view than they usually are in fishes.”54
Strikingly, though, a closer inspection of the position of the
hind limbs in his attempted restoration of the Ichthyostega
appears to contradict his assessment of the animal’s walking
abilities. In fact, his reconstruction showed the hind limbs with
the toes directed backwards, in the position in which they were
found.55
[Figs. 7a and 7b] While Jarvik himself confessed that
his investigation of the limbs had been superficial and prelimi-
nary, he still suggested that the position of the hind-limbs in
the fossils “may be accidental, but it is also possible, that the
foot was held in this position when the animal was swim-
ming.”56
But if only circumstantial evidence seemed to support
52
Jarvik, “On the fish-like tail”, p. 21.
53
Jarvik, “On the fish-like tail”, p. 26.
54
Jarvik, “On the fish-like tail”, p. 21.
55
Jarvik, “On the fish-like tail”, p. 84; see also Jarvik to Koch, 18/2-52, LK/7.
56
Jarvik, “On the fish-like tail”, p. 18.
26. 126
Inventing ‘the four-legged fish’
his conclusions, why, then, did he insist on interpreting the
Ichthyostega as a ‘walking fish’?
mangler
Fig. 7a. Photograph of one of the Ichtyostega specimens showing the tail and
hind leg. From Jarvik 1952.
27. 127
Ries
Fig. 7b. Drawing of the specimen shown in Fig. 7a, and another also showing a
tail and hind limb. From Jarvik, 1952.
Part of the explanation has to do with the general contemporary
scientific trend in thinking about tetrapod limb evolution. Back
in 1933 Alfred Romer of Harvard University, Massachusetts,
had offered a compelling scenario.57
Many Devonian rocks are
bright red, and in 1916 an American geologist named Joseph
Barrell suggested that this coloration meant that the rocks had
been baked dry in arid conditions. Inspired by Barrell’s ideas,
57
Romer, “Vertebrate”, 1933.
28. 128
Inventing ‘the four-legged fish’
Romer envisaged the Devonian ancestors of land-dwelling
tetrapods as relatives of lungfish living in freshwater pools that
suffered seasonal droughts. Like lungfish, they could breathe
air if oxygen became scarce in the water or the ponds dried
up. And some of these ancestors, Romer suggested, struggled
with their fins over the harsh land to another pond. Those with
more limb-like extremities were better able to struggle over dry
land and more likely to reach another pool. Fish with weak fins
died along the way; fish with strong ones lived to reproduce,
and gradually fins turned into limbs, which are much better
for overland travel. At the same time, many other parts of the
body - such as eyes, ears and skin - changed to better cope with
the new environment.
Fig. 8. Romer’s theory of tetrapod evoplution as illustrated by the Danish artist
and palaeontologist Gerhard Heilmann. Three types of crossopterygians are
vying for terrestrial survival: 1. Macropetalichthys, 2. Glyptolepis and 3. Eusthe-
nopteron. From Heilmann, 1940.
The middle decades of the twentieth century, and particularly
the 1950s, gave birth to many new theories on terrestrialisa-
tion and limb evolution. Generally, it was agreed that because
some crossopterygians had developed fins with a bone struc-
29. 129
Ries
ture like those of tetrapods, they must have used them in a
similar manner. Thus, changes to the locomotive system were
thought most likely to have occurred under aquatic conditions,
while only the selective pressure associated with excursions
onto dry land could have provoked the shedding of fin rays.
Some, like Jarvik, questioned Romer’s scenario of the drying
ponds, suggesting that it was the evolution of terrestrial vegeta-
tion during the latter part of the Devonian that had created the
necessary conditions for vertebrate colonisation of the land.58
But most scenarios were fundamentally similar to Romer’s
old tale: they presented the evolution of tetrapod limbs as a
response to the challenge of moving across dry land.59
[Fig. 8.]
It would be fair to say then, that Jarvik’s interpretation of
Ichthyostega – in spite of the somewhat disturbing position
of the animal’s hind legs – was consistent with the generally
accepted theoretical framework, coupling vertebrate terrestri-
alisation and tetrapod limb evolution. In fact, it was consis-
tent with the image of ‘a four-legged fish’ that Koch had been
pushing in the media since 1932, and Koch immediately hired
a journalist to make sure that Jarvik’s publication got all the
media attention it deserved.60
On 10th
February 1952 an article
in the Danish newspaper Socialdemokraten headlined “The
sensation predicted by Lauge Koch presented to science” and
reported of Jarvik’s “[...] sensational treatise on ‘the four-legged
fish’ including the first depiction of the animal.”61
Meanwhile Koch, now nearing his sixtieth birthday, was
haunted by sleepless nights worrying about his impending
retirement and the summing up of his many years of scientific
exploration in East Greenland. His lead-investigations had
inspired the Danish state, in cooperation with private contrac-
tors from Denmark, Sweden and Canada, to permit the newly
established ‘Nordic Mining Company’ to begin commercial
mining in Mesters Vig. Koch himself was detached from the
operation, working only as an occasional consultant for the
58
Erik Jarvik, “Crossopterygierna och de första fyrfota djuren”, Svensk Faunistisk
Revy, 1955, 3: 80-96, on p. 93.
59
Jennifer A. Clack, Gaining ground: the origin and evolution of tetrapods
(Indiana University Press, 2002), on p. 100.
60
Koch to Jarvik, 8/2-52 LK/7; Koch to Jarvik,18/2-52, LK/7.
61
“’Den firbenede fisk’ fra Grønland – en nøgle til udviklingshistorien”,
Socialdemokraten, 10/2-52.
30. 130
Inventing ‘the four-legged fish’
next couple of years.62
Koch was therefore ready to renew his
efforts at promoting ‘the four-legged fish’, and after another
sleepless night in February 1952, he wrote to Jarvik:
Only a few years ago East Greenland remained a distant fairy-tale
land, in which Norway challenged our national sovereignty (one
of the greatest Norwegian geological accomplishments may well
be, that their policy has eased my access to funding for my East
Greenland investigations), and later influential groups looked
favorably upon my continued investigations [...] Now that so
much wealth is to be gained up there, the situation has changed,
but of course I will never forget how ‘the four-legged fish’ has
aided me in my fundraising time and again. During my delibera-
tions last night I realized, that ‘the four-legged fish’ should not be
allowed to become just another zoo-palaeontological curiosity in
the future, and I decided to renew my efforts towards lifting the
investigations to a higher level.63
To that end, Koch asked Jarvik to prepare a confidential
report on the collecting work undertaken between 1929 and
1952, to be presented to possible investors and government
officials. Jarvik complied, spending the summer working up
the report, while stimulating public interest in ‘the four-legged
fish’ through interviews and articles printed in European and
American journals and newspapers.64
In December 1952 Jarvik’s report was ready for Koch to pres-
ent to the Danish Government together with his plans for future
investigations of the East Greenland Devonian vertebrates.65
While waiting for the politicians to evaluate his suggestions,
Koch urged Jarvik to stimulate public awareness by preparing
a popular scientific article on the basis of his report: “The ordi-
nary Danish newspaper reader knows of the existence of a ‘four-
legged fish’”, Koch wrote to Jarvik, “ but thinks that it is only
a single or very few specimens.” The article, Koch suggested,
should “present a picture of the number of people that have
62
Aksel Mikkelsen “Blyfundet i Mesters Vig”, Tusaat/Forskning i Grønland,
1992,3: 60-62 on p. 62.
63
Koch to Jarvik, 19/2-52, LK/7.
64
Jarvik to Koch, 12/6-52. LK/7.
65
Koch to Jarvik, 22/12-52, LK/7. See also Erik Jarvik: ‘Devonian vertebrates
from East Greenland collected between 1929-1952’, confidential report, LK/7.
31. 131
Ries
been involved in the search for ‘the four-legged fish’ over the
years and of the number of specimens that have been found,
while conveying – in very popular terms – the impression, that
we actually know of quite a large Devonian fauna.”66
Apparently Jarvik neither denied nor complied with Koch’s
request. It seems that Jarvik’s work load was growing in a peri-
od of poor economy and lack of staff at the Swedish Museum
of Natural History.67
In April, the Danish Government decided
not to back Devonian vertebrate investigation financially. But,
as Koch explained to Jarvik, there was still hope for the future:
“I have now bombarded the Government with arguments to
such an extent, that this morning even the Ministry of Finance
believed that some extra money could be granted already this
summer. Unfortunately, I have just now received a note, that
the Prime Minister (under whose jurisdiction I am) because of
the uncertain political situation and several General and Public
Elections etc., will not risk increasing my expedition budget
until next year.”68
Towards the end of the year, things began to look up, and
just before Christmas, Koch was able to promise Jarvik and a
couple of his assistants participation in his next expedition.69
Jarvik, on his part, had found time to work on the popular
scientific article requested by Koch, and in January 1954 he
reported his progress to Koch, asking for assistance:
No harm could probably come from cheering up the article by
reproducing the first reconstruction of a four-legged fish ever
published – to my knowledge, at least. It was done by Storm-
Petersen [Danish cartoonist] and published by some Danish
newspaper, probably around 1932-34. It shows some pipe-
smoking cavemen riding four-legs. Even if it is a bit anach-
ronistic, I still believe that such images will draw more atten-
tion, than our own more correct but less lively attempts at a
reconstruction. Is it possible to get hold of a good copy of this
picture so that it can be reproduced, and is that allowed?70
66
Koch to Jarvik, 27/1-53, LK/7.
67
Jarvik to Koch, 28/4-53, LK/7.
68
Koch to Jarvik, 8/4-53, LK/7.
69
Koch to Jarvik, 23/12-53, LK/7.
70
Jarvik to Koch, 9/1-54. LK/7. Jarvik is mistaken on the dating of the picture here.
It was first published in 1943 in the Danish newspaper B.T. (Jarvik, 1996, p. 5).
32. 132
Inventing ‘the four-legged fish’
Fig. 9. Storm Petersen’s cartoon of ‘the four-legged
fish’ which inspired Jarvik’s 1955 reconstruction.
For whatever reason,
S t o r m - P e t e r s e n ’s
reconstruction [Fig. 9.]
was not included in
Jarvik’s article, which
appeared in the popu-
lar scientific journal
Scientific Monthly in
March 1955.71
In its
place was a new recon-
struction by Jarvik
[See Fig. 2 on p. ?]: the
very same reconstruc-
tion, that would
become standard refer-
ence for the next four
decades, and with
which Clack, Ahlberg
and Blom juxtaposed
their own 2005 version
[see Fig. 1 on p. ?].
Jarvik’s 1955 reconstruction is quite similar to his 1952
version. But in the position of the animals hind-legs, it
resembles Storm-Petersen’s image. This fish was clearly made
for walking, and corresponds much more closely with the
description in Jarvik’s 1952 publication, than does the original
reconstruction. But the question remains why Jarvik decided
to twist the hind legs of his Ichthyostega around, in spite of his
comment in 1952, that he had depicted them ‘in the position
they have in the fossils’.
A letter from Jarvik to Koch sent in May 1954 shortly before
Jarvik’s submission of his article indicates that investigations
of the skeleton of the hind legs were still very preliminary, and
not at all ready for publication:
At last I have completed my popular article on the four-legged
fish, and will submit it in a few days. I have paid much atten-
71
Jarvik, “The earliest tetrapods”, 1955. An amended Swedish version of the ar-
ticle appeared in Swedish the same year: Erik Jarvik “Crossopterygierna”, Svensk
Faunistisk Revy, 1955, 3: 80-96.
33. 133
Ries
tion to the illustrations having produced amongst other things
a reconstruction of the whole skeleton and a new reconstruc-
tion of the whole animal with skin [...] Apart from this I have
worked much on the description of the skeleton of the extremi-
ties, a subject which, judging from the letters I have received,
attracts considerable attention. Most likely another two years
will pass before I can complete that article.72
Jarvik’s article on the extremities was never finished. After
1955 he turned again to his Devonian crossopterygians and the
defence of the controversial theory of the polyphyletic origin of
tetrapods. The Ichthyostega material remained in the Swedish
Museum of Natural History under Jarvik’s custody, but publi-
cation of the fossils was brought to an almost complete halt for
another forty years.
6. The re-petrification of the four-legged fish
Charting the fate of Ichthyostega between 1955 and 2005 falls
beyond the scope of this article. Still, a few remarks can be
made to sketch out the general situation.
Towards the end of the 1950s, Lauge Koch rapidly lost
political and monetary support for his East Greenland expedi-
tions. Jarvik and a couple of colleagues – Sven Erik Bendix-
Almgreen and Hans Bjerring - were able to join his expeditions
in 1955 and 1956, but after this Jarvik stayed at home while
Almgreen and Bjerring joined Koch’s last expeditions in 1957
and 1958. From then on, Koch was able to raise money only
for publication of previously collected material.73
These new
restraints might well be expected to have increased Koch’s
demands on Jarvik for a quick publication of Ichthyostega, but
curiously quite the opposite seems to have happened.
As Koch started to drift toward the margins of Danish
Greenland geology, the staff at the Danish Geological Museum
eyedthepossibilityofre-acquiringfromStockholmtheDevonian
collections from his expeditions. In October 1959, Koch wrote
to Stensiö: “As you know, the material belongs to the Danish
72
Jarvik to Koch, 25/5-54, LK/7.
73
Koch to Stensiö, 7/10-59, LK/9.
34. 134
Inventing ‘the four-legged fish’
state, and while I am still alive, we should make sure, that even
if the collections must in time return to Copenhagen, it will be
up to Jarvik to describe it.”74
In December Koch raised the issue
again, this time with Jarvik, who was taking over the profes-
sorship in palaeozoology upon Stensiö’s retirement that year. “I
was discussing other matters with the State Secretary”, wrote
Koch, “and I brought up the question [of ‘the four-legged fish’]
and said that one day when I am gone, the Geological Museum
will probably attempt to acquire the material, and I said that
this could not be done until it was published.”75
If Koch would
have his way, the material should stay in Stockholm until Jarvik
had made a full description of the animal.
Jarvik seemed to agree. Ichthyostega was still the earliest
known tetrapod, a palaeontological prize of considerable
scientific potential. He may have been busy enough with his
crossopterygian investigations, but still he was not prepared to
let the four-legged fish slip away. In 1960 the Danish Geological
Museum was planning to open an exhibition of Greenland
fossils in conjunction with the International Geological
Congress to be held in Copenhagen that summer. In March,
Eigil Nielsen approached Koch for a possible loan of some of
the East Greenland stegocephalians. Koch wrote of the meet-
ing to Jarvik: “[Nielsen] said: We do have a lot of Devonian
material to exhibit, but no four-legged fish. I promised to write
you immediately, and said that it might be possible for him to
borrow one or two specimens of the four-legged fish.”76
But Jarvik did not think so: “Regarding the exhibition at the
Geological Museum, it is my interpretation that we are dealing
with a more permanent exhibition, and not one to last only for
the duration of the congress. In that case it is difficult to know
what to do, since practically all the material we have is needed
for continued investigation.”77
The Danes were granted a
couple of casts and some photographs, but the originals stayed
in Stockholm. And so they did for another 36 years. Koch
retired in 1962 and died in 1964, leaving Jarvik with almost
74
Koch to Stensiö, 7/10-59, LK/9.
75
Koch to Jarvik, 22/12-59, LK/7.
76
Koch to Jarvik, 28/3-60, LK/7.
77
Jarvik to Koch, 6/4-60, LK/7.
35. 135
Ries
unlimited control of the four-legged fish. As long as he did not
finish his investigations, the creature was his for keeps.
But among Jarvik’s colleagues, his Ichthyostega was viewed
with growing distrust. During and after the 1950s Romer’s
theory, that the development of limbs in Devonian crossop-
terygians was a response to the challenge of venturing onto
dry land, was increasingly contradicted. Romer’s theory was
founded on the idea that the rocks, in which the Devonian cros-
sopterygians and tetrapods had been found, were red because
they had been baked in the sun during seasonal droughts, and
Jarvik’s version of a terrestrial Ichthyostega seemed to support
Romer’s theory. But in 1957 R. F. Inger (1957) made a strong
case against this scenario by arguing that the Devonian redbeds
in which many early sarcopterygians had been found had
formed in environments that were hot (tropical or subtropi-
cal) but not necessarily seasonally dry.78
Over the years, several
researchers corroborated this idea, suggesting that many of the
sediments constituting the Devonian redbeds were deposited in
marine, coastal or estuarine environments.79
Gradually, the once so influential ‘Stockholm school’ of early
vertebrate palaeontology was beginning to lose international
credibility. In the general context of evolutionary systemat-
ics arising in the 1940s and 1950s, the polyphyletic theories
of Stensiö and his followers had increasingly been viewed as
heretical. Jarvik’s rejection of the new trend of phylogenetic
systematics (cladistics) in the 1960s only increased his scien-
tific isolation. In later years international colleagues often
vividly expressed their opposition to Jarvik’s unusual ideas
about early vertebrate evolution at meetings and conferences.
He rarely replied in public, preferring to publish his arguments
years later in thoroughly argued papers or monographs.80
In 1964 a government decision threatened to rob the depart-
ment of Jarvik’s professorship, a move that was only prevented
by a flood of protest letters, gathered by Jarvik and Stensiö
78
Inger, R. F. (1957), “Ecological aspects of the origins of the tetrapods”,
Evolution, 11: 373-376.
79
Laurin, Meunier, Germain and Lemoine (2007), “A Microanatomical and
Histological Study of the Paired Fin Skeleton of the Devonian Sarcopterygian
Eusthenopteron Foordi”, Journal of Paleontology, Vol. 81, Issue 1: 143–153
80
Janvier, P. (1998), “Erik Jarvik (1907-1998). Palaeontologist renowned for his
work on the ‘four-legged fish’”, Nature, 1998, 392: 338.
36. 136
Inventing ‘the four-legged fish’
from specialists around the globe. Quite strikingly though, in
most cases, the argument for a continuation of the professor-
ship were made in reference to achievements made prior to
World War II.81
Jarvik’s professorship was saved, but by the
time he retired in 1972, early vertebrates had become only a
marginal occupation of the Department of Zoo-palaeontol-
ogy at the Museum of Natural History in Stockholm. Hans
Bjerring, Jarvik’s friend and long-time colleague in Stockholm,
recalls the situation:
When [Jarvik] retired, he had a drawer with some Greenland
material, which he studied and published a paper about [...]
After he finished, he said: “What the hell, Bjerring, nobody
takes an interest in what we are fiddling with.” And then the
idea arose in his mind – and I supported him, stimulating it to
make him completely familiar with it – that he should write
a book. [...] He wrote that book during the 1970s, and I was
in contact with him every day. He chiefly talked to me about
his work. With the others at the department, it was just ‘hello’
and ‘good bye’. There was never any conversation that way.
And that suited him fine.82
In 1980 Jarvik published his Basic Structure and Evolution of
Vertebrates. Vols. I & II, summing up his controversial ideas.
[Fig. 10. ] General remarks on Ichthyostega are found scattered
throughout the text, but still no monograph on the mysterious
creature had been published by Jarvik or by anyone else.
81
The complete set of letters is kept in a separate folder in Stensiös’ Archive at
The Royal Swedish Academy of Sciences in Stockholm.
82
Interview with Bjerring, 18/5-05.
37. 137
Ries
Fig. 10. Jarviks depiction of the polyphyletic origin of tetrapods from two differ-
ent types of crossopterygians. Here taken from an article in a Swedish popular
scientific journal, Jarvik, “Härstammer vi verkligen fråan fiskarna?” [Are we
really decended from the fishes?] Zoologisk Revy, 1961, pp. 5-11. The Swed-
ish caption reads: Man and most other four-legged animals are descended from
Devonian ‘toad-fishes’ (Osteolepiformes), while the urodeles have evolved inde-
pendently from another group of fishes (Porolepiformesi). Note that Ichtyostega
is depicted as a ‘blind alley’ in the evolution of tetrapods. This idea, which is
commonly accepted today, may have contributed to Jarvik’s reluctance to work
on the animal, since his primary interest was to find the link(s) between fishes
and modern tetrapods.
In 1985 Hans Bjerring, after having acquainted himself with
the roughly 250 available specimens of Ichthyostega, published
his own reconstruction of the creature suggesting that it was
38. 138
Inventing ‘the four-legged fish’
aquatic and hardly able to walk on land.83
[Fig. 11] According
to Bjerring, Jarvik simply ignored his reconstruction:
“Jarvik was special”, Bjerring remembers. “Once he had
formed an opinion, it was almost always difficult to get him to
change his mind. You had to have very strong arguments. [...]
He had his crocodile-like Ichthyostega. There it stood – stiff
– in profile. He said nothing. He has never commented on my
reconstruction. He had his reconstruction. He had the skeleton
from the side.”84
While Bjerring’s aquatic reconstruction of Ichthyostega gener-
ally received very little attention, Jarvik’s image of a terrestrial
‘four-legged fish’ retained its iconic status until the mid-1990s.
But pressure was slowly building up on Jarvik. According to
Jennifer Clack, who by the mid-1980s was beginning to take
and interest in early tetrapod evolution, “[...] it was a delicate
situation at the time”:
[Jarvik] had been working on Ichthyostega since the thirties
and forties, and he hadn’t really completed the work. He had
come out with one or two publications – one big one which
described the tail, and very little else. He’d been sitting on this
stuff. It’s not that he wouldn’t let anyone else look at it, but
they weren’t at liberty to publish anything on it. One respects
other people’s territories, and that was regarded as his.85
83
Hans Bjerring, Facts and thoughts on piscine phylogeny, pp. 31-97 in Foreman,
R.E.; Gorbman, A.; Dodd, J.M.; Olsson, R. (eds.), “Evolutionary Biology of
Primitive Fishes”, Plenum Press, New York 1985. See also Hans Bjerring, “Armar
och ben i utvecklingshistorisk belysning”, Fauna och flora (Stockholm) 1988,
83: 58-74. Another version of the same drawing, but without external gills, was
published in Hans Bjerring Svalg- och gälspringor. Deras ursprung och vidare
öden, pp. 131-140 in Kjell Ebgström (ed.) ”Naturen berättar” (Naturhistoriska
Riksmuseet. Stockholm, 1989) A different reconstruction showing Ichthyostega
swimming under water was published by Klembara in 1991: Jozef Klembara
“Nové poznatky o najstarsich stvornozcoch”,Vesmir, 1991, 70: 88-91,
84
Interview with Bjerring, 18/5-05. Interestingly, Bjerring’s article is included in
the bibliography of Jarvik’s 1996 Ichthyostega monograph.
85
Quoted from Carl Zimmer, At the waters edge: fish with fingers, whales
with legs, and how life came ashore and then went back to the sea (New York:
Touchstone, New York, 1998) on p. 50.
39. 139
Ries
Fig. 11. A more aquatic Ichtyostega as suggested by Bjerring. From Bjerring,
“Armar och ben i utvecklingshistorisk belysning” [An evolutionary perspective
on arms and legs], Fauna och Flora, 1988, p.72.
Jennifer Clack’s chance came in 1987, when she managed to
get permission for her, her husband Rob and Per Ahlberg, then
a graduate student at Cambridge University, to join a Danish
team going back to the region for the Greenland Geological
Survey. In that season, not only remarkably well-preserved
material from several Acanthostega individuals – among them
one complete skeleton - but also new Ichthyostega fragments
were recovered from Celsius Bjerg.
Over the following years, investigations of the new material
revealed Acanthostega as a Devonian tetrapod that had prob-
ably never left the water.86
Its four limbs were relatively long,
but ill suited to support its weight. It had well developed fingers
86
See e.g. Coates, M. I. and Clack, J. A., “Fish-like gills and breating in the earli-
est known tetrapod”, Nature, 1991, 352: 234-236; Clack, J. A. and Coates, M.
I., “Acanthostega – a primitive aquatic tetrapod?” in Arsenault, M., Leliévre, H
and Janvier, P. (eds.) Proceedings of the 7th
International Symposium on Lower
Vertebrates, Bulletin du Muséum National d’Histoire Naturalle, Paris, 1995: 359-
373. Jennifer Clack’s web-page on Acanthostega can be found at http://www.tol-
web.org/Acanthostega. For a popular account of the early work on Acanthostega
cf. Zimmer, C. “Coming onto the land”, Discover, 16, 1995: 118-127.
40. 140
Inventing ‘the four-legged fish’
and toes, but no wrists or ankles. It had a hipbone, which fishes
lack, but it was too weakly attached to the spine to be able to
support much weight. The spine was well suited for swimming
motions, but hardly able to support any weight. Its short and
thin ribs would have been incapable of protecting and support-
ing internal organs when affected by gravity on dry land. The
tail, bearing a large bony fin, was clearly used for swimming.
And while it did have lungs, it also had internal fish-like gills.
But the fact remained, that alongside all the fish-like charac-
teristics, Acanthostega did have legs and feet, rather than fins.
Since it was essentially contemporaneous with the apparently
more terrestrial Ichthyostega, a possible explanation for its
contradictory anatomy was that Acanthostega had once come
onto the land, but had subsequently returned to the water,
gradually losing the skeletal features needed for life on land. But
the internal fish-like gills on the creature seriously contradicted
this theory. All amphibians that returned permanently to the
water developed external gills – feathery tissue extending out
from the body as seen in some present-day salamanders. But
Acanthostega still breathed like a fish, the strong implication
being that Acanthostega was a tetrapod evolved from fish in
the water for a life in the water.
Faced not only with Acanthostega and the challenges it posed
to traditional ideas about the evolution of limbs as a response
to a more terrestrial life-style, but also with a new independ-
ent stock of Ichthyostega fossils, Jarvik was left with only two
options: publish his Ichthyostega, or throw in the towel, and
let the fish-tetrapod transition pass to a younger generation of
researchers. Jarvik decided to publish. Slowly and painstak-
ingly he worked on his manuscript until in 1995, at the age
of 88, he suffered a crippling stroke. By then he had finally
completed the bulk of a 200-page manuscript, which, with the
loyal assistance of Hans Bjerring, was organized, prepared and
published in 1996 with a reconstruction of Ichthyostega simi-
lar to Jarvik’s 1955 version in almost every detail.87
After Jarvik’s death in 1998, the material that had been
his for nearly 50 years, was finally handed over to the
Danish Geological Museum in Copenhagen. Ironically, it was
87
Erik Jarvik ,“The Devonian tetrapod Ichthyostega”, Fossils and Strata, 1996,
40: 3-213.
41. 141
Ries
immediately sent to the University Museum of Zoology in
Cambridge, England, where Jennifer Clack, Per Ahlberg and
lately also Henning Blom have been reassessing it since, yield-
ing in 2005 a Ichtyostega distinctly more aquatic than Jarvik’s
‘four-legged fish’.
7. Concluding remarks
‘The four-legged fish’ was first brought to life in the geo-politi-
cal turmoil concerning East Greenland in the 1930’s. Prompted
by Norwegian claims to parts of the Danish colony, the Danish
government mustered considerable political and economic
support for Lauge Koch’s expeditions, expecting in return sensa-
tional scientific results that would swing international opinion in
Denmark’s favour, and convince the International Court in The
Hague, that Denmark made good use of its Arctic possessions.
The find of a Devonian tetrapod was exactly the kind of
thing that was needed. Having it worked over by experts
at Stensiö’s world-renowned Department of Palaeobiology
at the Swedish Riksmuseum only served to boost the sensa-
tion. But while Ichthyostega seemed to promise answers for
important and difficult questions about tetrapod evolution, the
material was still too sparse and unique for Säve-Söderbergh
to feel completely comfortable about it. He therefore saved
Ichthyostega for later, and turned towards other material in an
attempt to establish a wider foundation for understanding fish-
tetrapod relations. At this point, scientific investigation lagged
behind while Koch, for political as well as financial reasons,
eagerly and liberally promoted the sensation as the catchingly
named ‘four-legged fish’.
Up to and during World War II, the context for scientific
investigation of Ichthyostega changed in a number of ways. The
Danish victory over Norway in The Hague lifted the political
urgency formerly attributed Koch’s activities. At the same time,
Koch’ssuccessandlackofconsiderationforhisDanishcolleagues
spawned frustration and hostility against him, culminating in
the ‘Lauge Koch Case’ and seriously weakening Koch’s position.
Shortly after, the outbreak of World War II and the German
occupation of Denmark put a stop to all Danish Greenland
expeditions, and to the otherwise steadily growing stock of
42. 142
Inventing ‘the four-legged fish’
Ichthyostega material in Stockholm. Further impediment was
caused by the protracted illness – and subsequent death – of
Säve-Söderbergh. With no further progress being made, Danish
claims to Koch’s collections were more easily justified. It was
only Stensiö’s uncompromising refusal to let go of the tetrapods
that prevented them from ending up in Copenhagen.
After World War II, Koch – despite the setback experienced
during the war – managed to restart his expedition activities.
Still, faced with the competition from the newly founded
Greenland Geological Survey, Koch had to work harder to
secure political and economical backing. Again, Koch turned
to Ichthyostega. But while he had some success in raising
money for continued collecting, the situation in Sweden was
less than favourable. After Säve-Söderbergh’s death in 1948,
Stensiö insisted that the material should go to Jarvik, who
was still preoccupied with his crossopterygians. In Denmark
Eigil Nielsen, now employed at the Geological Museum in
Copenhagen, was being pushed as a real and well-experienced
candidate to taking over the tetrapods. Koch therefore needed
results to justify the continued lingering of the material in
Stockholm. The pressure that had been building upon Jarvik
could not be ignored for long, and in 1952 Jarvik – although
somewhat contradicted by his own observations – confirmed
the idea of the animal that had been pushed by Koch since it
was first discovered 30 years earlier: a fish that could walk on
land, as well as live in the sea.
By then Koch was beginning to drift towards the fringes of
Danish Greenland exploration. Still eager to sum up his many
years of East Greenland exploration, he again urged Jarvik to
publicly promote ‘the four-legged fish’ as a draw for continued
expedition support. It was as a response to this request that
Jarvik made his revised 1955 popular scientific reconstruction
of the standing Ichthyostega, not on the basis of new investiga-
tions of the limbs, but rather in order to meet Koch’s demand
for publicity.
But the scheme to re-launch ‘the four-legged fish’ as a magnet
for political and financial interest met only limited success, and
in 1958 Koch was forced to terminate his expedition activi-
ties for good. From then on, the pressure on Jarvik was lifted
by Koch, who now seemed more concerned with keeping the
fossils away from the Danish geologists than with getting the
43. 143
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work done. Jarvik, accordingly, gave up on Ichthyostega to
pursue his interest in the crossopterygians, and when Koch died
in 1964 Jarvik was left in complete control of the material. As
long as Ichthyostega remained the only known Devonian tetra-
pod, no one could challenge his interpretation, however feeble
its foundation might have been.
Jarvik’s reconstruction of Ichthyostega was influenced by
many factors, but not by an overwhelming amount of scientific
evidence. In fact, his alteration of the position of the hind limbs
in 1955 was based mostly on circumstantial evidence, and in
direct conflict with observations made by himself in 1952, and
later verified by Ahlberg, Clack and Blom in 2005. Generally
speaking, Jarvik’s Ichthyostega was well suited to common mid-
twentieth-century notions of a causal relation between limb
evolution and vertebrate adaptation for terrestrial life. More
specifically, however, it was the durability of ‘the four-legged
fish’ as popular scientific icon, the long-winded investigative
process and Koch’s constant demand for scientific justification
that set the frame for Jarvik’s interpretation of Ichthyostega as
the first vertebrate ever to have walked the land.
![102
Inventing ‘the four-legged fish’
during this period vertebrate palaeontologists deliberated on
the form and status of Ichthyostega in the history of evolution,
the image of a ‘four-legged fish’ settled in the public imagina-
tion to such a degree, that it shaped scientific lore about the
animal until the late 1990s.
1. Introduction
In September 2005 a new and long awaited reconstruction of
the Devonian tetrapod Ichthyostega appeared in Nature.2
The
reconstruction, proposed by palaeontologists Jennifer Clack,
Per Ahlberg and Henning Blom, was juxtaposed with another
published in 1996 by the Swedish palaeototlogist Erik Jarvik
(1907-1998) 3
[Fig. 1]. For more than 40 years Jarvik had
remained the international authority on Ichthyostega, main-
taining with only very minor revisions his reconstruction first
published in 1955 in the popular scientific journal American
Scientific4
[Fig. 2].
Fig. 1. Top: the new reconstruction of Ichtyostega according to Clack, Ahlberg
and Blom. Bottom: Jarviks reconstruction as depicted in Jarvik, 1996. Source:
Clack, et al., “The axial skeleton…” Nature, 2005.
2
Jennifer A. Clack, Per Ahlberg and Henning Blom, “The axial skeleton of the
Devonian tetrapod Ichthyostega”, Nature, 2005, 437:137-140.
3
Erik Jarvik, “The Devonian tetrapod Ichthyostega”, Fossils and Strata, 1996,
40:1-213.
4
E. Jarvik, “The earliest tetrapods and their fore-runners”, Scientific Monthly,
1955, 3:141-154](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)