IN: Kowalewski, M., and P.H. Kelley, (eds.), 2002. 
The Fossil Record of Pr?dation. Paleontological 
Society Papers, 8: 395-398. 
THE FOSSIL RECORD OF PREDATION: 
METHODS, PATTERNS, AND PROCESSES 
The papers assembled in this volume show 
compellingly the methodological, topical, and 
conceptual richness of paleontological research on 
pr?dation. Such studies span a broad spectrum of 
organisms and a wide range of observational scales, 
from individual interactions to global-scale secular 
trends. The fossil record offers us diverse and 
provocative evidence of predator-prey interactions 
through time, ranging from pr?dation traces to 
functional morphology and phylogenetic affinities. 
In recent years, these diverse data have become a 
base for posing increasingly sophisticated questions 
and for testing increasingly complex hypotheses. 
As clearly demonstrated in this volume, 
pr?dation can be defined in a variety of ways. A 
predator can be defined very broadly as "an 
organism killing another organism for nutritional 
purposes" (Bengtson; see also Labandeira; Lipps 
and Culver; Brett and Walker), or the definition 
may be restricted behaviorally by excluding 
organisms that kill by passive filter-feeding, so that 
predators are only "those organisms that hunt or 
trap, subdue, and kill individual animals that have 
some capacity for either protection or escape" 
(Bambach; see also Kowalewski). Pr?dation as a 
concept may be restricted to macro-camivory? 
with a predator then defined as "a large animal or 
sometimes a plant consuming part or the whole of 
another animal" (Vermeij)?or can be expanded 
to include tiny organisms, like foraminifera 
subduing and eating larger animals (Lipps and 
Culver), or even behaviors that involve the killing 
of plants (e.g., seed pr?dation; Labandeira). Thus, 
the definition of pr?dation varies significantly 
among researchers. The term pr?dation may also 
include related behaviors along a spectrum from 
active pr?dation to scavenging, from lethal 
pr?dation to partial (sublethal) pr?dation, 
parasitism, and amensalism (see Baumiller and 
Gahn; Labandeira; Kowalewski; Vermeij). 
METHODS 
The chapters included in the first part of the 
volume review a variety of methods that can be 
applied to study the fossil record of pr?dation. 
Various direct and indirect indicators of pr?dation 
are available to paleontologists, including trace 
fossils, coprolites, gut contents, exceptional 
preservational events, taphonomic patterns, and 
indirect evidence provided by functional 
morphology and phylogenetic affinities 
(Kowalewski). Because of the highly disparate 
nature of the data itself, variable research goals, 
and even personal idiosyncrasies, the methods 
used to study ancient predator-prey interactions 
are very diverse. 
Among various lines of evidence, trace fossils 
left by predatory activity offer a particularly rich 
source of quantifiable data (Kowalewski; see also 
Haynes; Lipps and Culver; Brett and Walker; Walker 
and Brett; Baumiller and Gahn; Farlow and Holtz; 
Bengtson; Dietl and Kelley; Vermeij); and various 
analytical approaches for studying trace fossils can 
be fruitful depending on the nature of the material 
and the scientific goals of paleontological projects 
(Kowalewski). Coprolites and stomach contents also 
provide a wealth of direct data on ancient predator- 
prey interactions and are widely used for studying 
the diet of ancient predators, from marine inverte- 
brates to tewestrial vertebrates (Chin; see also Brett 
and Walker; Walker and Brett; Labandeira; Farlow 
and Holtz). In addition to the pr?dation traces studied 
by paleontologists, anthropologists have developed 
a distinct set of qualitative and quantitative methods 
for studying the hunting behavior of hominids, not 
only to distinguish between scavenging and 
pr?dation, but also to draw the much more subtle 
distinctions among different butchering behaviors, 
such as skinning, meat-stripping, or sectioning of 
animal carcasses (Haynes). 
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PALEONTOLOGICAL SOCIETY PAPERS, V. 8, 2002 
The methods part of this volume shows that 
the methodological dimension of research on the 
fossil record of pr?dation is a rapidly growing field 
of study, with many promising future research 
directions ?particularly through laboratory 
experiments, observations in present-day 
ecosystems, and numerical modeling. Clearly, we 
need to continue improving our statistical tools and 
analytical strategies and to work together on 
erecting some general methodological guidelines 
for studying the fossil record of pr?dation. 
PATTERNS 
The chapters included in the second part of this 
volume impressively document the range of 
evidence related to predator-prey interactions that 
has been amassed by paleontologists. However, 
these studies also point to the numerous temporal 
and taxonomic gaps in our current knowledge. 
The fossil record of microorganisms provides 
insights into primary producers and secondary 
consumers in marine ecosystems over the last 3.8+ 
billion years, and points to a long-term increase 
in the complexity of trophic structures of marine 
ecosystems through the history of life (Lipps and 
Culver). In particular, the trophic strategy of 
endosymbiosis between animals and microbes, 
especially photosynthesizing algal eukaryotes, 
seems to have long played an important role in 
marine ecosystem development and the evolution 
of organisms (Lipps and Culver). 
The marine invertebrate fossil record offers a 
spectacular wealth of evidence relating to predator- 
prey interactions, including trace fossils, coprolites, 
and functional morphology of prey and predators 
(Brett and Walker; Walker and Brett). These 
predatory records suggest that long-term 
evolutionary changes in pr?dation pressure are 
linked to episodes of abrupt biotic reorganization 
during and after mass extinctions, punctuating 
longer interludes of relative stability (Brett and 
Walker; Walker and Brett). Moreover, the evolution 
of pr?dation in the pelagic realm may have been 
largely decoupled from its evolution in benthic 
ecosystems. The data fi-om the marine fossil record 
make a strong case for the existence of predatory 
attack on shelled organisms as early as the latest 
Precambrian and the early Cambrian?with a 
further intensification of pr?dation during the 
middle Paleozoic paralleled by increases in 
spinosity and other potentially defensive traits of 
the prey skeleton (Brett and Walker). In contrast, 
late Paleozoic forms may have taken refuge in 
smaller size and resistant, thicker-walled skeletons 
(Brett and Walker). Following the end-Permian 
mass extinction, the data suggest episodic, but 
generally increasing, pr?dation pressure on marine 
organisms through the Mesozoic-Cenozoic 
interval. Pr?dation in benthic communities may 
have intensified substantially in the Late 
Cretaceous-Early Cenozoic with the evolution of 
neogastropods, varied crustaceans, and 
durophagous fish. In the early to mid-Mesozoic, 
large-predator guilds were filled predominantly by 
varied marine reptiles; whereas neoselachian 
sharks, teleosts, and marine mammals dominated 
in similar roles throughout the Late Cretaceous to 
Cenozoic (Walker and Brett). 
The marine invertebrate record also supplies 
evidence relating to parasite-host interactions, 
with a nearly even distribution of reported cases 
through the post-Cambrian Phanerozoic 
(Baumiller and Gahn). However, in few of the 
reported examples can we explicitly distinguish 
parasitism from pr?dation, commensalism, or 
mutualism; and only in exceptional cases (such 
as interactions involving platyceratids and 
crinoids) is the evidence for parasitic interactions 
sufficiently compelling (Baumiller and Gahn). 
Terrestrial and freshwater invertebrates also 
provide a diverse fossil record of pr?dation, 
parasitoidism, and parasitism?with evidence for 
carnivory (i.e., taxonomic affiliation, fossil 
structural and functional attributes, organismic 
damage, gut contents, coprolites, and mechanisms 
indicating predator avoidance) occurring from the 
mid-Paleozoic to the Recent (Labandeira). 
However, only 12 invertebrate phyla have become 
carnivorous in the continental realm and only the 
two most diverse groups (nematodes and 
arthropods) left behind a comparatively good 
fossil record (Labandeira). 
396 
CLOSING REMARKS 
Major groups of amniote predators such as 
theropod dinosaurs and carnivorous synapsids offer 
a continuous fossil record of predator-prey 
interactions in the terrestrial realm. The fossil 
record of predatory theropod dinosaurs suggests 
that the taxonomic composition of dinosaurian 
predator-prey systems varied notably as a function 
of time and geography (Farlow and Holtz). Details 
regarding diet and hunting behavior of theropods 
can be inferred from their functional morphology, 
supported by evidence from taphonomic 
associations with likely prey species, bite marks, 
gut contents, coprolites, and trackways (Farlow and 
Holtz). Following the K-T extinction, carnivorous 
birds (the direct descendants of theropods) 
remained prominent predators throughout the 
Cenozoic Era (Farlow and Holtz). 
The fossil record of synapsids points to 
significant parallels between the diversification of 
non-mammalian synapsid predators in the Late 
Carboniferous-Triassic and the Cenozoic 
radiation of mammalian predators: both groups 
evolved sabertooth forms as well as short-snouted, 
powerful biting forms (Van Valkenburg and 
Jenkins). Both radiations are characterized by 
repeated patterns in which one or a few clades 
evolved large size and dominated the carnivore 
guild for several million years, but then declined 
and were replaced by new taxa (Van Valkenburgh 
and Jenkins). Both non-mammalian and 
mammalian synapsid clades show trends toward 
increasing body size and hypercamivory over time 
(Van Valkenburgh and Jenkins). 
PROCESSES 
The last part of this volume includes chapters 
that provide an introduction to some major models 
regarding the origin and history of pr?dation as well 
as the evolutionary role of predator-prey 
interactions through time. 
Although data on early life are understandably 
scarce, existing data and theoretical considerations 
suggest that pr?dation may have played an 
important role in some of the major transitions in 
evolution, including the origin of eukaryotic cells, 
the origin of multicellularity (as a means of 
acquiring larger size), the decline of stromatolites, 
the diversification of acritarchs, and the Cambrian 
explosion (Bengtson; see also Lipps and Culver). 
Pr?dation may have been a decisive selective force 
behind the transition from simple, mostly microbial, 
ecosystems to those with complex food webs and 
higher-order consumers (Bengtson; Lipps and 
Culver). Following the Cambrian explosion, the 
diversity of predators and the proportion of the total 
fauna represented by predators have both increased 
throughout the Phanerozoic, implying that 
ecosystems have increased their ability to support 
either more predators or more specialization among 
predators (Bambach). This pattern may be linked to 
a secular increase in diversity and biomass of 
primary producers, and changes in the composition 
of prey taxa (Bambach). 
The evolutionary importance of pr?dation 
remains a hotly debated topic. Arms races between 
predators and prey may be driven by two related 
processes: escalation?enemy-driven evolution, in 
which the role of prey in the evolution of the 
predator is downplayed?and coevolution?in 
which two or more interacting species respond 
reciprocally to one another; prey are thought to 
drive the evolution of their predator, and vice versa 
(Dietl and Kelley; Vermeij). In the fossil record, 
the two processes are distinguished most reliably 
when the predator-prey system is viewed within the 
context of the other species that may influence the 
interaction, thus allowing for a relative ranking of 
the importance of selective agents (Dietl and Kelley). 
Scale is also important in evaluating the role of 
escalation and coevolution in the development of 
species interactions: prey are likely to exert some 
selective pressure on their predators over ecological 
time scales, but predators may still exert primary 
"top-down" control in directing evolution over 
evolutionary timescales. In the long term, predators 
have two principal effects: they influence prey 
phenotypes and they restrict prey to environments 
where predators are rare (Vermeij). Predators likely 
control overall directionality in evolution because 
of the inequalities of predator and prey in control df 
resources (Vermeij; Dietl and Kelley). Indeed, 
predators have the evolutionary upper hand over 
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PALEONTOLOGICAL SOCIETY PAPERS, V. 8, 2002 
the long run, especially in the expression of sensory 
capacities, locomotor performance, and the 
application of force; and only in passive defenses 
(armor, toxicity, large body size) does escalation 
favor the prey (Vermeij). The evidence provided by 
the fossil record points to increases over time in both 
predator power and prey defenses. These escalatory 
increases have proceeded episodically (Brett and 
Walker; Walker and Brett; Vermeij) against a 
backdrop of generally increasing productivity 
(Bambach) and increasing top-down evolutionary 
control by high-energy predators (Vermeij). 
MiCHAL KowALEwsKi, PATRICIA H. KELLEY, RICHARD K. BAMBACH, TOMASZ K. BAUMILLER, STEFAN 
BENGTSON, CARLTON E. BRETT, KAREN CHIN, STEPHEN J. CULVER, GREGORY P. DIETL, JAMES O. 
FARLOW, FOREST J. GAHN, GARY HAYNES, THOMAS R. HOLTZ, JR., IAN JENKINS, CONRAD C. 
LABANDEIRA, JERE H. LIPPS, BLAIRE VAN VALKENBURGH, GEERAT J. VERMEU, AND SALLY E. WALKER 
398