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PALEONTOLOGICAL SOCIETY PAPERS, V. 8, 2002Baszio’s (2001) report of fish coprolites withterrestrial arthropod remains, including insects, fromthe middle Eocene Messel Deposit of Germany.Mechanisms of Predation Avoidance.—Thereare two broad classes of defense strategies by meansof which terrestrial invertebrates avoid predation.First, there are those that involve resemblance of apotential prey’s external body to another organismor aspect of its ambient environment. Second, thereis physical deterrence based on increasing the levelof difficulty for predation, exemplified by thepresence of spines. Instances of the resemblance ofone organism to another in color, overall form, orbehavior are well documented among moderninsects, and are likewise represented in the fossilrecord. The three basic types of protection aremimicry (both Batesian and Müllerian versions),warning coloration, and crypsis (Price, 1997). Formimicry, the fossil record provides few clues todistinguish the Batesian type, where a palatablemimic resembles an unpalatable model, from theMüllerian type, where both the mimic and the modelare distasteful or otherwise negatively affect thepredator. However, in some fossil examples,determination of mimicry can be approached bymodern analogy (Jarzembowski, 1989). Oneexample is the distinctive color banding on thedigger wasp Palaeapis from the Jurassic-Cretaceousboundary of China (Hong, 1984) (Fig. 2G), whichprobably was a model. Another example, the soldierfly “Stratiomys” from the late Eocene of southernEngland (Jarzembowski, 1976), likely was a mimic.Other instructive examples of the use of color andpattern for protection include the disruptivecoloration—with light and countershaded darkpatterns—on the wings of canopy-inhabitingpaleodictyopteroid insects, presumably to enhanceconcealment when viewed from below, or perhapsrepresenting an example of aposematic (warning)coloration for potential dragonfly predators fromabove (Shear and Kukalová-Peck, 1990).Additionally, there is a fossil record of distinctivewing eyespots, which function in extant insects toinflate apparent size and to startle predators (Preston-Mafham and Preston-Mafham, 1993). Such warningcoloration occurs in a protorthopteran from the LateCarboniferous at Mazon Creek (Carpenter, 1971)(Fig. 2D), as well as throughout the later Mesozoicin the planipennian family Kalligrammatidae, abutterfly-like lineage in which some species boreprominent eyespots (Panfilov, 1968; Jarzembowski,1984). Unlike mimicry and warning coloration,crypsis (camouflage) in the fossil record has faceda more checkered interpretation: one of the bestexamples is the resemblance of Late Carboniferouscockroach wings to seed-fern pinnules, first notedby Scudder (1895). Subsequent observers such asPruvost (1919) and North (1931) expanded thetaxonomic scope of this pinnule similarity byextending it to orthopteroid insects. The resemblanceof cockroach forewings to seed-fern pinnules,however, is more likely attributable to structuralconvergence—based on biomechanical principlesfor the support of planated structures—than toprotective camouflage (Shear and Kukalová-Peck,1990; Jarzembowski, 1994). A similar criticism canbe applied to Fischer’s (1979) argument regardingthe subaerial occurrence of the horseshoe crabEuproops and its proposed concealment amid leafyLepidodendron shoots, whose elongate leavesresemble the animal’s carapace spines. The mostperplexing possible occurrence of crypsis is the leaflikecolor patterns on the tegmina of the MiddleTriassic grasshopper Triassophyllum (Papier, et al.,1997), which resembles certain fern leaves withangiosperm-like venation.Evidence of defenses against predatorsinvolving spines, large size, and protective domicilesoccurs sporadically throughout the fossil record.From the Upper Carboniferous, the herbivorousMazon Creek form Gerarus bore robust andradiating prothoracic spines that evidentlyfunctioned for predation deterrence (Shear andKukalová-Peck, 1990), a feature found in moderntropical grasshoppers and other insects. In the samedeposit and throughout the Late Carboniferous,many terrestrial arthropods achieved great size,including arthropleurid myriapods, the arachnidMegarachne, paleodictyopteroids, protodonatandragonflies, and even Diplura and Zygentoma(silverfish) (Dudley, 1998). Although this gigantismis ultimately attributable to atmospheric oxygen218