The behaviour of the mealworm beetle pupa and its conditioned reaction to the geomagnetic field turn.
|Year of publication||2006|
|Type||Article in Proceedings|
|Conference||3rd European Conference on Behavioural Biology. Physiological Mechanisms in Behavioural Ecology.|
|MU Faculty or unit|
|Keywords||insect pupa magnetoreception|
|Description||Pupae of holometobolous insects are not immovable and insensitive development stages although they might seen so. Their behavioral display is restricted to rotations and contractions of the abdomen but the range of amplitudes extends from the microscopic contractions in order of tenths of microns up to clearly visible jerks. This way, pupae react spontaneously and surprisingly sensitive to irritating mechanic, light or sound stimulations. In our work, we monitored the abdomen reactions of the mealworm beetle Tenebrio pupae to the geomagnetic field 60deg turn. By means of the micromechanic registration we recorded the peaks of abdomen contractions and compared the data obtained after the magnetic treatment with those preceding the treatment. Spontaneous reaction to the magnetic stimulus was not significant. Nevertheless, by means of a negative reinforcement training we succeeded to elicit a significantly higher irritation activity after the magnetic pulse. Such conditioned magnetosensitive reaction was present even in darkness indicating the reception mechanism be light-independent. Sensory capacities of the insect pupae and their behavioral performance show that pupae ethology may enrich the spectrum of the behavioral neurophysiology methods. The neural base and the adaptive value of the geomagnetic sense of non migrating species like mealworm beetle Tenebrio are still to be discovered.|