Head grooming behaviour in the praying mantis

Mantis head grooming is a rhythmic behaviour pattern involving co-ordinated movements of head and foreleg. The probability of grooming is influenced by releaser concentration, while the number of cycles/episode is influenced by concentration and amount of releaser. Within a grooming episode (usually 4 to 6 cycles) successive cycles are longer in duration; this is primarily caused by an increase in the actual head cleaning phase, although all three phases increase in duration. The phase cleaning the femur brush is most sensitive to feedback effects from releaser substances. It is concluded that head grooming is a programmed, i.e. centrally organized, movement pattern responsive to peripheral feedback. First approximations to the model-equations and model-hypotheses are presented.     

On display behaviour and courtship in the praying mantis Ephestiasula amoena (Bolivar)

Display behaviour in a small species of Indian praying mantis, Ephestiasula amoena , is described and the possible role of this display in courtship is discussed. The display involves exposure of the bright pattern on the inside face of the expanded plate-like profemora. The profemoral patterns found in closely related species are discussed and it is suggested that the display may also play a role in species recognition. The courtship behaviour of E. amoena is contrasted and compared with the courtship of other species of praying mantis.     

Coordinated movements of the head and body during orienting behaviour in the praying mantis Tenodera aridifolia

The visual orienting behaviour towards prey in the free-moving mantis was investigated with a high-speed camera. The orienting behaviour consisted of head, prothorax, and abdomen rotations. Coordinated movements of these body parts in the horizontal plane were analysed frame-by-frame. Rotations of these body parts were initiated with no or slight (≤40 ms) differences in timing. The initiation timing of prothorax-abdomen rotation was affected by its initial angle before the onset of orienting. There were positive correlations in amplitude among head-prothorax, prothorax-abdomen, and abdomen rotations. The ratio of these rotations to total gaze rotation was affected by the initial prothorax-abdomen angle before the onset of orienting. Our data suggest that coordinated movements of the head, prothorax, and abdomen during orienting are ballistic events and are pre-determined according to visual and proprioceptive information before the onset of orienting.     

Visual deprivation and distance estimation in the praying mantis larva

Abstract. Young larvae of the praying mantis, Tenodera sinensis Saussure, were placed on an off-centre island surrounded by a round arena with six black bars painted on a white inner wall. In this situation, it was shown that the horizontal peering movements of the head often seen in mantids are in fact used to measure distances; motion parallax may be involved in this process. Aimed jumps that followed peering were taken to be the distinct result of an absolute distance measurement. Specific visual deprivation such as painting over of certain parts of the eye with opaque black varnish or degeneration of the fovea with sulforhodamine showed that: absolute evaluation of distance is only possible with two fully intact eyes; the peering mechanism is under visual control; and visual experience has a long-term effect on distance measurement involving peering movements.     

A chemical correlate of learning in a praying mantis

Bidimensional and unidimensional maps of amine-containing components extracted from brains of the praying mantis (Stagmatoptera biocellata) were obtained using high-voltage electrophoresis and chromatography, and high-voltage electrophoresis alone.Bidimensional maps from control insects, i.e. animals that did not receive training, showed four distinctive spots and one less intense spot (number 5). On the other hand, bidimensional maps from trained animals, i.e. mantids that were trained not to attack a moving star, showed the same spots 1–4, plus an intense spot (number 5) and an extra componet (number 6).Unidimensional maps from brains of mantids that were trained not to attack a moving star (‘star-group’) showed two extra components in comparison with maps from the control insects. On the other hand, when mantids received training similarto that of the star-group, but using a fly that could not be caught as a stimulus, instead of a mobile star, they did not learn and their maps were similar to those from control mantids.The techniques used in this paper to obtain the maps suggest that they are maps of peptides of low molecular weight. The possible correlation between the appearance of extra spots in the maps and a learning process is discussed.     

Changes in brain peptides and memory consolidation in the praying mantis

A praying mantis (Stagmatoptera biocellata) faced with a bird (Padda orzyvora) displays a frightening reaction called a deimatic reaction (DR). Habituation of this response takes place after repeated presentation of the bird (no-DR training). The purpose of the present paper is to: (a) attempt an analysis of the effect of anoxia at various times with different types of no-DR training; (b) study the dynamics of those types of training that cause habituation but not consolidation, in order to use these groups of animals as controls of groups that show both habituation and consolidation; and (c) test a correlation between the no-DR memory consolidation and the appearance of specific amine-containing components in high-voltage electrophoregrams obtained from brains of the mantids.     

The midline metathoracic ear of the praying mantis,Mantis religiosa

Summary The praying mantis, Mantis religiosa, is unique in possessing a single, tympanal auditory organ located in the ventral midline of its body between the metathoracic coxae. The ear is in a deep groove and consists of two tympana facing each other and backed by large air sacs. Neural transduction takes place in a structure at the anterior end of the groove. This tympanal organ contains 32 chordotonal sensilla organized into three groups, two of which are 180° out of line with the one attaching directly to the tympanum. Innervation is provided by Nerve root 7 from the metathoracic ganglion. Cobalt backfills show that the auditory neuropile is a series of finger-like projections terminating ipsilaterally near the midline, primarily near DC III and SMC. The auditory neuropile thus differs from the pattern common to all other insects previously studied.     

Defence behaviours of the praying mantis Tenodera aridifolia in response to looming objects

Defence responses to approaching objects were observed in the mantis Tenodera aridifolia. The mantis showed three kinds of behaviour, fixation, evasion and cryptic reaction. The cryptic reaction consisted of rapid retraction of the forelegs under the prothorax or rapid extending of the forelegs in the forward direction. Obstructing the mantis’ sight decreased its response rates, suggesting that the visual stimuli generated by an approaching object elicited the cryptic reaction. The response rate of the cryptic reactions was highest for objects that approached on a direct collision course. Deviation in a horizontal direction from the direct collision course resulted in a reduced response. The response rate of the cryptic reaction increased as the approaching velocity of the object increased, and the rate decreased as the object ceased its approach at a greater distance from the mantis. These results suggest that the function of the observed cryptic reactions is defence against impending collisions. The possible role of the looming-sensitive neuron in the cryptic reaction is also discussed.     

Cannibalistic siblicide in praying mantis nymphs (Miomantis caffra)

Inclusive fitness theory predicts that cannibalism should be more likely to arise if close relatives can be avoided, suggesting that cannibalistic species will possess mechanisms for minimizing predation on kin. Juvenile Miomantis caffra are good candidates for the possession of such traits because; (1) groups of siblings hatch together into the same locale, (2) they are aggressive hunters, and (3) they are strongly cannibalistic. In this study, the possibility of kin recognition or avoidance in M. caffra is investigated by laboratory comparison of cannibalism rates between groups of differing relatedness. In order to examine the likelihood of encounters between early instar siblings, the extent of dispersal away from the ootheca in the days following hatching is also observed. Nymphs did not rapidly disperse after hatching, so the chances of full siblings encountering one another in the wild appear to be high. Despite this, cannibalism was equally high in groups of full siblings and groups of mixed parenthood. We suggest that for M. caffra, a generalist ambush predator, the benefits of indiscriminate aggression may outweigh any inclusive fitness benefits that would be gained from kin discrimination.