Oviposition Digging in the Grasshopper
نویسندگان
چکیده
1. Transection of the ventral nerve cord of female grasshoppers activates the rhythmical motor programme for oviposition digging. 2. Electrical stimulation of the cut nerve cord had the following effects on elicited oviposition motor activity: (i) shortand long-lasting inhibition of activity, (ii) phase resetting and (iii) modulation of burst frequency. 3. Cold saline applied to the nerve cord reversibly elicited the oviposition motor programme. 4. The effects of transection and stimulation at different levels of the nerve cord indicate that the higher neural control of the motor pattern is not confined to the head ganglia, but includes a thoracic component. 5. In intracellular recordings of ventral opener motoneurones, stimulus-related IPSPs were observed in response to stimulation of the cut nerve cord. Stimulation also abolished slow wave synaptic input to the motoneurones during inhibition of the oviposition motor programme. 6. It is suggested that oviposition digging behaviour is initiated and maintained by a mechanism of 'release' from descending neural inhibition.
منابع مشابه
Oviposition digging in the grasshopper. I. Functional anatomy and the motor programme.
The ovipositor appendages of acridid insects (grasshoppers and locusts) consist of two pairs of shovel-shaped valves that are used to dig a deep chamber in the ground for egg burial, to manipulate the eggs, and to assist in capping the egg-pod with froth. During oviposition the valves undergo cyclical opening, closing, retraction and protraction movements. These movements are produced by the co...
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