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PALEONTOLOGICAL SOCIETY PAPERS, V. 8, 2002the 420-million-year continental invertebraterecord. These and more typical deposits (Figs.1,2)provide six types of evidence for carnivory:taxonomic affiliation, structural and functionalattributes, organismic damage, gut contents,coprolites, and mechanisms of predationavoidance—all but the last of which are analogousto those cited for recognition of arthropod herbivory(Labandeira, 1998b, 2002a). Of these types ofevidence, taxonomic affiliation is most often used,whereas coprolites from vertebrate or insectcarnivores are rarely reported (Thulborn, 1999).Functional and structural attributes as well asdamage to organisms are more frequent in the fossilrecord, but have been underused for inferring dietsand life habits. Gut contents provide a “smokinggun” by establishing both the carnivore and its prey,but are rarely preserved. Mechanisms of carnivoreavoidance, such as mimicry, spines, large size, larvalcases, and the presence of auditory tymbals foravoiding aerial predators are recognizable fromanalogous patterns in the modern world, but becomemore problematic deeper in the fossil record(Labandeira, 2002a). In fact, the applicability oftaxonomic uniformitarianism for understandingcarnivory decreases into the geologic past, andmust be supplemented or supplanted by other,intrinsic approaches such as structural andfunctional attributes or gut contents.Taxonomic Affiliation.—Obvious invertebrateclades that are pre-eminent carnivores are theChilopoda (centipedes), Araneida (spiders),Odonatoptera (dragonflies and damselflies),Mantodea (mantises), the Raphidioptera,Megaloptera, and Planipennia (snakeflies, alderflies,lacewings, and relatives), the Carabidae (groundbeetles), Dytiscidae (predaceous diving beetles), andAsilidae (robber flies) (Fig. 2J), among many others.For these taxa, which have phylogenetic continuityto the present day, a taxonomic uniformitarianapproach is valid. An extensive literature hasdocumented the obligate dependence of these extantgroups on live prey (Withycombe, 1922; Clausen,1940; Brues, 1972; Sih, 1987; Hagen, 1987; Foelix,1996; Corbet, 1999). A uniformitarian approach isalso applicable to fossil representatives of animalendoparasites such as tylenchid and mermithidnematodes, which consume live internal tissues(Poinar, 1991; Weitschat and Wichard, 1998); andectoparasitic lice (Fig. 2H) and fleas (Fig. 2L), whichfeed on dermal and subcutaneous tissues. Muchdiscussion of extant carnivory is centered onmouthpart structures and their association with diet(reviewed in Labandeira, 1990) and behavior,drawing inferences from functional morphology. Indiverse taxa that encompass multiple diets andfeeding strategies and larval stages—for example,leiodid and meloid beetles, and ants—a finertaxonomic resolution is necessary for certitude indietary assignments.There are instances in which prey andcarnivore are preserved in conjunction, especiallyin single pieces of amber (Weitschat and Wichard,1998; Kutscher and Koteja, 2000a), and frequentlyinvolving ants as predators. Many of theseexamples represent predator-prey interactions thatoccur today. Perhaps the ultimate directdemonstrations of carnivory are those samples ofBaltic amber in which a predatory ant is graspinga scale insect with its mandibles (Kutscher andKoteja, 2000b), or a spider is grasping a capturedant (Weitschat and Wichard, 1998). Other samplespreserve parasites or parasitoids exiting the bodycavity immediately after envelopment by resin(Weitschat and Wichard, 1998; Poinar and Poinar,1999). Lastly, there are amber specimens whereectoparasites such as mites or nematodes areentombed with mouthparts firmly attached to theirhost’s intersegmental membrane (Poinar et al.,1994a, 1997; Weitschat and Wichard, 1998), ordisplaying body distension due to engorgement ofhost hemolymph (Poinar et al., 1991).Structural and Functional Attributes.—Continental invertebrates possess several structuresthat indicate carnivorous habits. Prominent amongthese are mouthparts. Also included are body shape,the presence of attachment suckers, auditorytympanal organs, spider spinnerets, specializationsof the legs, ovipositor type, and cerci. Amongmandibulate hexapods, head mobility andforwardly positioned mouthparts are associatedwith predation (Walker, 1932), as are mandibles214