The Behavior of Atlanticus Testaceus (Orthoptera: Tettigoniidae) on the E.S. George Reserve, Michigan

Several reports deal in part with the systematics, distribution, or habits of one or another of the shield-backed katydids of the orthopteran genus Atlanticus. Included are Blatchley (1920), Cantrall (1943), Caudell (1907), Davis (1893), Hebard (1934), McNeill (1891), Rehn and Hebard (1916), and Scudder (1894). One species of the genus, A. testaceus (Scudder), is found commonly throughout Michigan and has interesting habits. As the species\u27 feeding behavior was poorly understood, the author undertook an investigation dealing with that subject. The results are in press. During the course of that study much information was obtained on certain non-feeding aspects of the species\u27 behavior. Findings with respect to the latter are given below. The project was carried out during the 1958-1961 field seasons at the University of Michigan\u27s Edwin S. George Reserve, a biological preserve near the village of Pinckney, Livingston County, Michigan. The general area is described in detail in Cantrall\u27s excellent report on the Reserve\u27s Orthoptera (1943) and in less detail in the author\u27s monograph on food selection in Orthoptera (1961). The specific sites of study, Southwest Field and Southwest Woods, are described in Gang- were (1965) and Gangwere (in press), respectively. The latter two re- ports may also be consulted for information on the techniques used during the study

Relationships between the Mandibles, Feeding Behavior, and Damage Inflicted on Plants by the Feeding of Certain Acridids (Orthoptera)

[excerpt] In 1960 the author described three fundamental patterns of feed- ing in Orthoptera and their allies and emphasized the close correlation that exists between the insects\u27 mouthpart structure, food, and feeding pattern. An article by Anderson (1964) made reference to these described patterns and discussed possible modifications of them. To the author\u27s knowledge these are the only reports available that make other than casual mention of the characteristic damage by Orthoptera to food plants. Numerous other papers include figures that depict orthopteran damage, and still others verbally describe the damage inflicted by various economically important species. In all these reports at least one basic consideration has been all but ignored: the possible relationships between mandibular form, pattern of use, and the resulting damage to food plants

A study of the feculae of Orthoptera, their specificity, and the role which the insects'mouthparts, alimentary canal, and food-habits play in their formation

2 láminasMany physiological studies have been carried out on different aspects of the feculae ("feces") and their formation in Orthoptera (sens. lat.). Among the more important of these researches are ones by Nenjukov and Parfentjev (1929), Nielsen (1943), and Snipes and Tauber (1937), who described for various species the speed of transit of food through the alimentary canal, i. e., rate of formation of feculae; Chauvin (1946), the periodicity of defecation in four species ; Bro-wn (1937) and Chauvin (1941), the biochemistry of feculae ; Brown (1937), their structure ; and numerous authors, the general physiology of digestion and excretion in Orthoptera. Surprisirigly, however, purely descriptive studies on feculae have lagged. Frost (1928; 1959) reviewed insect "scatology", but included scant material relative to Orthoptera ; Weiss and Boyd (1950) described and figured the feculae of three species of Orthoptera, and Boldyrev (1928) did the same for a species of katydid ; and Day (1950) described, but did not figure, those of a species of cockroach.Peer reviewe

The Food-Habits and Biology of Acrididae in an Old-Field Community in Southeastern Michigan

(excerpt) Inasmuch as the earth supports a wide variety of terrestrial communities differing in size and species composition, and because no two of these communities are identical in terms of foods and feeders, a correspondingly great complexity of feeding relationships is to be expected. Consequently, food-habit studies must take cognizance of dynamic interplay among many factors which vary with place and time, including that between food availability and the food preferences of consumers. Although ecologists have developed some sophisticated models of the various feeding interactions (e.g., Holling, 1963, 1964, 1966), the number of species whose food-habits and preferences have been carefully studied is small. Further knowledge is needed, particularly of the feeding biology of organisms in specific, limited communities and ecosystems

Male Weaponry in a Fighting Cricket

Sexually selected male weaponry is widespread in nature. Despite being model systems for the study of male aggression in Western science and for cricket fights in Chinese culture, field crickets (Orthoptera, Gryllidae, Gryllinae) are not known to possess sexually dimorphic weaponry. In a wild population of the fall field cricket, Gryllus pennsylvanicus, we report sexual dimorphism in head size as well as the size of mouthparts, both of which are used when aggressive contests between males escalate to physical combat. Male G. pennsylvanicus have larger heads, maxillae and mandibles than females when controlling for pronotum length. We conducted two experiments to test the hypothesis that relatively larger weaponry conveys an advantage to males in aggressive contests. Pairs of males were selected for differences in head size and consequently were different in the size of maxillae and mandibles. In the first experiment, males were closely matched for body size (pronotum length), and in the second, they were matched for body mass. Males with proportionately larger weaponry won more fights and increasing differences in weaponry size between males increased the fighting success of the male with the larger weaponry. This was particularly true when contests escalated to grappling, the most intense level of aggression. However, neither contest duration nor intensity was related to weaponry size as predicted by models of contest settlement. These results are the first evidence that the size of the head capsule and mouthparts are under positive selection via male-male competition in field crickets, and validate 800-year-old Chinese traditional knowledge

The phylogenetic development of food selection in certain Orthopteroids

The horse, Equus, has long enjoyed a k-ind of pre-eminence in the eyes of biologists. So instructive and apparently well-documented are the facts of its evolution that a discussion of them is a part of most elementary courses in zoology. Several decades of students have beeil taught that the horse finds its origin in the Eocene with the rise of the humble forest-dweller Eohip pus. This cat-sized animal of browzing habit was dramatically transformed into modern Equus through a series of increases in body size and changes in teeth and legs adapting it for a cursorial, grazing existence. These adaptations followed known changes in the Tertiary landscape from moist woodland to dry grassland.Peer reviewe

The mechanical handling of food by the alimentary canal of Orthoptera and alijes

2 láminasDufour's classic "Recherches Anatomiques et Physiologiques sur les Orthoptères" (1841) contained an early comparative treatment of the digestive canal in Orthoptera and alijes. Since Dufour many workers have contributed studies relating to the alimentary system of these important, interesting insects. Among the more salient are those of Bordas (various papers, especially 1897, 1897 a), dealing with the morphology of the digestive tracts of various orthopteroids, and Walker (1949), summarizing present-day knowledge on the subject. More specialized contributions have been made by Albrecht (1953, 1956), Bryantseva (1951), Carpentier (1937), Hodge (1936, 1939, 1940, 1943), Williams (1954), and many others. In none of the published work has there been detailed discussion of possible relationships between the structure of the tract and the nature of the food mass it handles mechanically.Peer reviewe

The structural adaptations of mouthparts in Orthoptera and Allis

5 láminasThe Orthoptera (sens. lat.), long favorite types for classroom study, llave had much written about their mouthparts. Laboratorv manuals and textbooks account for many published descriptions, though their focus is not aimed at either Orthoptera or mouthparts. Other descriptions are contained within various formal reports which discuss the mouthparts and sometimes the general morphology of given species or groups. These papers are not cited because of limitations of space. It is sufficient to note that they contribute to an improved knowledge of range of form within the order but seldom discuss function. Still other reports are essentially comparative anatomical treatments dealing entirely or in part with mouthparts of Orthoptera. These include papers by Crampton (1916, 1921, 1923, 1928) (insect head and mouthpart structure); Snodgrass (1928, 1935, 1951) (general insect morphology) ; Golden (1926) (the mandibles and maxillae in representative Orthoptera); Cook (1944) (the clypeus and labrum in selected insect groups); Walker (1931) (the clypeus and labium in selected insects); Walker (1933) (comparison of the Grylloblatta head and mouthparts with those of other Orthoptera); and Yuasa (1920) (the classic survey of head and mouthpart structure in Orthoptera).Peer reviewe

Biting in Orthoptera and their allies

Orthoptera of some subfamilies bite when handled carelessly, while those of other subfamilies rarely do so. This behavior has not been reviewed, and the little that is known about it is recorded perfunctorily within reports on other topics. It is probably more common than is indicated by its scant literature ; those who are sufficiently trained in entomology to report defensive biting are expert in handling the insects and not likely to be bitten. The vast majority of bites, therefore, go unrecorded. 'Whatever the extent of biting-, it is of interest both in terms of its possible biological significance and because it hurts.Peer reviewe