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Crypsis Brakefield, P.M Crypsis Brakefield, P.M. Citation Brakefield, P. M. (2003). Crypsis. Encyclopedia Of Insects. Eds V.h. Resh And R.t. Carde, 269-273. Retrieved from https://hdl.handle.net/1887/11224 Version: Not Applicable (or Unknown) License: Leiden University Non-exclusive license Downloaded from: https://hdl.handle.net/1887/11224 Note: To cite this publication please use the final published version (if applicable). Cry psi s 269 MATING SYSTEM acts involving significant force, but the reverse does not seem to have happened. Groups of features related to the history of he long-range female-attracting songs and long tactual cerci insect mating acts have significance for interpreting changes °r crickets are components of a unique mating system, some in diagnostic features of major groups of insects, including aspects of which evidently trace to the earliest instances of cerci, .intennae, gcnitalia, wing structure, long-range com- copulation in the insect line and help explain changes leading munication, and modes of pair formation. to 'he current major groups of insects. Thus, none of the Distinctive morphological and behavioral features of primitively wingless modern insects copulate, while all winged crickets, especially those related to their methods of pair ar>d secondarily wingless insects do, the majority with the male formation and mating behavior, make them a pivotal group mounting the female and in some way holding or forcing her. in understanding insect evolution and phylogeny. n primitively wingless insects, however, a sac or bulb con- taining the sperm (a spermatophore) is transferred indirectly See Also the Following Articles to the female without direct copulation. Like crickets, some ol Cultural Entomology • Folk Beließ and Superstitions • these particular primitively wingless insects possess prominent Hearing» Orthoptera tactual cerci (e.g., Thysanura), used to guide the female during spermatophore transfer, as also in cockroaches and mayflies, Further Reading n all insect groups of ancient origin that have prominent Alexander, R. D. (1961). Aggressiveness, icniioriality. .nul sexual bdumour tactual cerci, transfer of the spermatophore is a luring act in in field crickets (Orthoptcra: ( ii\ llul.ic). Rrhaviour 17, l .W-223. which the female either mounts (winged and secondarily Alexander, R. O. (1966) The evolution ol uiikct chirps. Nat. Histnry Mag. V| ngless forms) or stands beside the male (primitively wingless 75,26-31. orms). In some crickets, such as the field cricket genus Gryllus, Alexander, R. l'. (1%8). lite ivile origins, spei i.ition, and related copulatory act appears unique among all animals in being phenomena in UK km. Q. Rev. fiinl. 43, 1-42. Alexander. R. 11. (!%')). Arthropods. /«"Animal Communication" (R. Schenk. entirely luring, with no evidence of controlling force by the ed.). 1 si ed.. pp. l 67-21 S. Indian.) University Press. Bloomington. e at any stage. The female' is .ittraded initially by the long- Alexander. R. II., and Cltte. II. (1967). The évolution ot" genit.ili.i and ange calling song and then by the male's close-range courtship mating behavior in crickets (Civllul.u-) and othei Otthoptera. Université ;°ng and probably the fluttering touches of his antennae of Michigan Museum ol /oology Miscellaneous Publication No. 133, 'g- 7). As in nearly all crickets, most close relatives of crickets, pp. 1-62. Huhn, l.. Mooie. T. K. and l.oher, W. (eels.) (I1)«1)). "Cricket Behaviour and most cockroaches and mayflies (the last aerially), the and Neurobiologv. ' Cornell University Press, Ithaca, NY. em ale mounts (or flies above) the male in the copulatory act. One, 11. (l')')2). l-'voluiion of ciiikct songs. /. Ort/wfitrm Res. 1, 25-49. PParently in correlation with the male field cricket having One, 11. (1'I'M). The crukeis ot'Hawaii: Origins, svstcmams, and evolution. ulnimal ability to clasp the females genital parts, the In "Pnhlii .liions on Orlhoplctan lliversiiy." The Orthoptcrists' Society. Perrnatophore is transferred quickly, in 15 to 90 s. The Academy ol Natural Suciucs. Philadelphia. One, II. (1994). Orthoptera species file 1: Crickets (Crvlloidca). /„ 'ermatophore is osmotically self-emptying, so that sperm "Publications on Orthopteran Diversity." The Orthoptcnsis' Society. lection occurs largely after the female dismounts from the Academy ot Natuial Siieiues, Philadelphia. e- In forms related to crickets, such as Tettigoniidac and One, II., and Alexander, R. 11. ( 1983). The Australian crickets (Ortlioptera: fera, m which males have evolved terminal claspers on the Civllidae). Aiadcniv of Natural Si icm es ot 'Philadelphia Monograph No. ornen, the tactual cerci have disappeared and copulation 22, pp. 1-447. One, 1). and Naskrccki, P. (1997). Orthoptera species file online at rnucn lengthier. In Caelifera the mating act has evolved http://viccrov.cch.iu on n.cdu./Ol I hoptera. c that the male mounts the female, though still reaching neath her to attach the genitalia; here, unlike Tettigoniidae, intennae have also become much shorter. Apparently n S copulatory acts in insects have repeatedly evolved into Crypsis Paul M. Brakefield Leiden University rganisms with bright and conspicuous color patterns O tend to attract the most attention both scientifically and aesthetically. However, the majority of insects and other animals rely on camouflage or crypsis for survival from predators that hunt them by sight. Furthermore, crypsis may 7 Adu extend to include the other senses, namely, smell, touch, and latt(,r -'t female (left) and male (right) Phyllnpalpus pulrhellus. the 1 pu , brewings in singing position. (Photograph courtesy ol I >a\ id II. sound. Indeed, any stimulus or signal that can alert a potential predator could be expected to become part of a 270 Cryps is FIGURE 1 Crypsis illustrated for different insects. (A) An individual of the dry se- on the forest floor in the Shimba Hills, Kenya. The insect is at the ce ""'""^ ' L"""S ^ rCSt'ng am°ng dead l that resembles a dead patch on a large leaf in a forest in Costa Rica (wing fsAVÎIÎ" "^/T"8 ^ * * 4'5 cm' (B) A '™» f 7 Lasiocam idac on a tree trunk in the Shimha Hills, Kenya; it is ca. 6 cm in length and b pod nedht U 7*^ °L ^ ° *' k™' f «^ rotated 90 degrees). (D) The same larva when actively moving in the s h—tally, head to the nght, in the center of the photo (im^- h,s IK,,, -ction along a tw,g. See text for further details. (Photographs hy the author.) coordinated suite of cryptic traits. A form of crypsis is also different genetic and developmental pathways, and yet shown by some predators that disguise themselves by assuming the same color and patterns as the background on evolution has led to a corresponding perfection of matching, albeit using entirely different mechanisms of pattern which they hunt. H. B. Cott in 1940 wrote perhaps the best known book on animal color patterns, but many of the great formation. Such an example of an underlying complexity of patterning is given by some caterpillars of the family entomologists of the 19th century had already considered insect camouflage. It is not usual to consider insect crypsis as Lasiocampidae that rest on the bark of trees and survive by a subject of applied biology but there are certainly many resemblance to the background color pattern of the bark, parallels with military expertise in either the hiding of or the including epiphytic lichens and algae (Fig. 1C). Such larvae searching for personnel and armaments in a landscape. are encircled by long hairs that are flattened around their margin when at rest. This breaks up their shape, smoothing their outline. These hairs are also patterned in a very specific COLOR MATCHING AND CRYPSIS way and one that is fully coordinated with the body cuticle, An insect that is perfectly camouflaged is perhaps one of the including the short bristles of the dorsal areas of the body most striking exhibitions of the power of evolution by segments. These elements are exposed, and the whole insect natural selection to mold and adapt organisms to fit their becomes highly conspicuous as soon as a larva is forced to environment and to maximize survival and reproductive move along a twig of fine diameter (Fig. ID). success. Wonderful examples of camouflage are presented by Furthermore, color matching in cryspis is almost always many species of insects, including some butterflies in tropical only one component of the strategy for survival; both habitat forests (Fig. 1A), which rest on carpets of dead brown leaves. )ice and, frequently, the adoption of very specific patterns The apparent perfection of crypsis is emphasized in many behavior and activity are required for effective crypsis. such insects by a similarity of, and matching of, the color e such example is shown by some species of moths ih.n pattern of the wings, body, and appendages to the cam crypsis by appearing to be a dead patch of tissue within background on which they normally rest. The color pattern large leaf on which they rest (Fig. IB). They achieve this of these different body parts and structures must involve >t only through the generally brown color of their wings i some details of patterning, which may resemble small Cry f sis 271 Patches of fungal-attacked leaf tissue, but also through a are active at night and rely on background matching and precise positioning on the leaf. For example, the moth in the crypsis for survival from birds during daylight hours. Survival photograph of Pig. 1 B has rolled up the leading edge of its enables males to mate at night and females to lay their eggs torewing, wrapped its abdomen along the trailing edge of one over a number of nights. The gaseous (e.g., sulfur dioxide) nind wing, hidden its appendages, and positioned itself and particulate (soot) air pollution produced by industry both a'ongside the midrib of the leaf.
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