A History of Ideas in Ichnology - Trace Fossils as Indicators of Sedimentary Environments - page 18

Contrary to what one might expect, the acceptance of Nathorst's ideas did
not result in a new ichnological revolution. Paradoxically, the disprovement of
fucoids brought a decline in interest for trace fossils and a consequent stagnation
in ichnological research. The factors accounting for this phenomenon include
the nomenclatural problems associated to traces, which consequently fell into
a no-man's land (see Knaust, 2012a ). Additionally, fucoids apparently lost their
biostratigraphical value and their application as indicators of shallow-marine,
euphotic environments ( Cad´e and Goldring, 2007; Osgood, 1975 ). Possibly,
this crisis was exacerbated by the aftermath of World War I, corresponding
to dramatic social, economic, and geopolitical effects. Notably, four empires
disappeared: the German, Austrian-Hungarian, Ottoman, and the Russian.
The French School was the first to be struck by the ichnological crisis,
and its once dominant contribution stopped after the previous polemic. Only
diverse short and obscure works were published; the nature of Zoophycos
(

Cancellophycus ) created some debate, but French scholars interpreted it
as an alcyonarian or a sponge (see the studies of Lucas, Dangeard in Supple-
mentary Material: http://booksite.elsevier.com/9780444538130 ). The same
happened in the other major center of the Period of Reaction, Scandinavia,
where trace fossils received sporadic attention. Nathorst himself returned to
the study of fossil plants ( Cad´e and Goldring, 2007 ).
This was a critical moment for ichnology at a global scale. For instance,
Italy's ichnological school waned and trace fossils were only reported as a sup-
port of stratigraphical works. In Britain, the pioneer work on modern traces in
the Wadden Sea by the German school at Frankfurt and Wilhelmshaven in the
1920s and 1930s ( Cad´e and Goldring, 2007 ), which established modern scien-
tific ichnology, passed virtually unnoticed. This resulted from the language bar-
rier, lack of European cooperation after World War I, and very little field
paleontology or sedimentology in this period. Spain and Portugal saw numerous
but regional works, driven by the first extensive geological mapping of the
Iberian Peninsula.
Amore complex scenario involved easternEurope. Poland envisaged the same
decline as the rest of Europe, with only marginal mentions of trace fossils. At the
same time, Czechoslovak geology gained a couple of internationally recognized
experts in ichnology, Bed ˇ ich Bou ˇ ek and Ferdinand Prantl. The first one focused
on Skolithos ; the second suggested a facies divisionof regional units based on trace
fossils, to some extent looking forward to the future ichnofacies concept (Supple-
mentary Material: http://booksite.elsevier.com/9780444538130 ) .
In many Eurasian countries, bedding-plane structures were referred to as
hieroglyphs ( Fuchs, 1895 ), composed of physical and biogenic sedimentary
structures; in their strict sense, hieroglyphs corresponded to graphoglyptids
( H¨ntzschel, 1975 : W17). The area of influence of the Soviet Union produced
a vast number of studies on this subject. Specifically, much of the work on
hieroglyphs is associated with the names of Grossheim, Vassoievitch, and
Bogatschev, who studied material from the Caucasus, Carpathians, and

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