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LABANDEIRA—PREDATORS, PARASITOIDS, AND PARASITEScharacterized by incisiform and shearing teethrather than broad molar shelves for grinding(Samways et al., 1997). In insects with stylatemouthparts, such as flies with piercing-and-suckingbeaks, serrate or barbed mandibular stylets orblades indicate hematophagy (blood feeding)(Borkent, 1995; McKeever et al., 1991).Additionally, elongate and falcate mandibles thatare distally curved are almost always borne bypredators, some of which display a complicated “trapjaw” mechanism such as larval antlions and manyadult ants (Korn, 1943; Gronenberg, 1996). Othertypes of mouthparts are fashioned as co-coordinatedmultielement structures that can be hurled at preyimmediately anterior of the head, such as the labialmask of aquatic odonatopterans (Pritchard, 1976)or the adhesive labial sling of some terrestrial rovebeetles (Betz, 1996), both of which demonstrateobligate predation. Although it is the mouthparts ofinvertebrates that most directly interact with prey,other external appendicular structures are used tosubdue potential victims, including raptorialprothoracic legs armed with spines in Mantodea,cerci modified into forceps in japygid Diplura(telsontails), ovipositors designed to penetratearthropod hosts for insertion of parasitoid eggs(Fig. 2F), or chelate tarsi used for grasping hairamong ectoparasites of warm-blooded tetrapods(Askew, 1979; Godfray, 1994) (Fig. 2E).Additionally, extrasomatic structures may revealcarnivory, such as nits, or eggs glued to hair shafts,that are deposited by ectoparasitic lice (Weitschatand Wichard, 1998) (Fig. 2K). Other fossilizablestructures produced by carnivores are silk webs thatensnare potential prey (Bachofen-Echt, 1934;Gerhard and Rietschel, 1968; Weitschat andWichard, 1998). The body structures responsiblefor spider silk have a record extending back to theMiddle Devonian (Shear et al., 1989a) (Fig. 2B).Organismic Damage.—Carnivory can result inmany kinds of damage to continental invertebrates.This damage can occur on the prey or host oralternatively on the carnivore itself, and includesteratologies (abnormal growths) (Poinar and Poinar,1999), amputated appendages or broken bodyprocesses (Petrunkevitch, 1942; Rolfe, 1985;Hannibal and Feldman, 1988), small exit holes ofparasitoids from cocoons (Houston, 1987; Bown etal., 1997) (Fig. 2N), prey items wrapped by spidersilk (Weitschat and Wichard, 1998), excavated softtissue of arthropods consistent with predation(Poinar, 1999a), and refuse accumulations ofdiscarded victim carcasses (Abel, 1935; Weitschatand Wichard, 1998). These examples involveunusual removal or alteration of tissue that resultsfrom both unsuccessful and successful predationattempts; and they indicate the behavior of apredator located at a stationary site for an extendedtime. Although plant rather than animal individualsare killed, there is a fossil history of seed predationextending to the Late Paleozoic (Zherikhin, 1989;Labandeira, 2002a), characterized by variousmodes of removal of endosperm or its nutritiveequivalent in plants (Sharov, 1973; Genise, 1995;Mikulas et al., 1998) (Fig. 2M). An analogoussituation is that of palynivory (Fig. 2A)(Labandeira, 1998b, 2000).Gut Contents.—Instances of terrestrialinvertebrates preserved in the digestive tracts ofpredators are extremely rare in the fossil record.Regurgitated gut contents have been identified inmacerated material from the Middle DevonianGilboa deposit in New York State and are attributedto trigonotarbid arachnids (Gray and Shear, 1992).Large carnivorous insects such as protodonatandragonflies should reveal boluses of insect-bearingmaterial, but due to the rarity of preserved and intactsoft tissues, only one specimen is known: a terminalabdomen with a dark, oval mass within the lastsegment (Durden, 1988). The best examples of gutcontents in the fossil record come from mammals ofthe middle Eocene Messel oil shale of Germany. Thisdiverse assemblage contains gut contents from severalarchaic antecedents of extant mammalian orders.They include the bat Palaeochiropteryx that preyedon beetles and especially primitive moths andbutterflies active at night, dawn, or sunset (Franzen,1985) (Fig. 2I); the hedgehog Pholidocercus, whosestomach contents include beetles and other types ofinsects (Von Koenigswald et al., 1992); and theanteater Eotamandua, an avid consumer of termites,among other insects (Storch and Richter, 1992). It215