著者

恩藤 芳典

出版者

一般社団法人 日本生態学会

雑誌

生態誌 (ISSN:00215007)

巻号頁・発行日

vol.9, no.4, pp.159-167, 1959

被引用文献数

1

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The analyses of the behavior reactions to the vibrating stimuli have been attempted only on some aquatic insects and terrestrial spiders. There have been some reports of direct reactions (taxes) to the vibrating stimuli, for example, by EGGERS (1926,1927) on Gyrinus ; by SHIMA (1940,1942) and by HONJO (1945) on Dineutus ; afterwards by BAERENDS (1950) on Notonecta. On the other hand, MORI (1938,1950) recorded the tidal rhythmic activity of a small bivalve, Donax semignosus, a sandy-beach inhabitant with a rhythmic behavior evoked with the stimuli of mechanical vibrations caused by waves. No direct reaction to the vibrating stimuli, however, has been investigated on a small terrestrial crustacean. It is no doubt due to the difficulties of controlling and measuring the conditions and evolving technique as accurate and precise as that can be used when mechanical vibration is the stimulus. The author has shown that the shore sowbug, Tylos granulatus, takes a characteristic behavior under natural conditions, to and from the water edges, accompanied with the periodic movement of waves in the night (ONDO, 1958). The present work is attempted to analyse the mechanisms in a behavior qualitatively, in terms of elementary animal behavior. Experimental analyses were carried out in the laboratory, using fresh and reared materials from 1954 to 1956. The material, apparatus and methods to relaese the direct reactions to the vibrating stimuli used in the study have been discribed in the previous paper (ONDO, 1958). Some results obtained will be stated in this paper. 1. Animals exhibit a turning locomotion avoiding the stimuli when the substratum of vibrating plate was vibrated and an approaching to the region of low intensity. In such behaviors, it is confirmed by means of the two-stimuli-source experiment and the unilateral removal of receptors, that negative tropo-taxis does occur, i.e., being removed the left (right) antenna, animals move round in general leftwards (rightwards) just like a circus movement. 2. When seven distal segments of both the second antennae were removed, animals still were able to response to the stimuli of mechanical vibration caused by electric tuning fork, but if the second basal segments of both antennae were removed, the sense of vibrating stimuli was lost. These results may only be understood, when it is assumed that the receptor of vibrating stimuli is located on the second basal segments of both antennae. 3. Periodic behavior accompanied with the periodic movement of waves is based upon the sense of the mechanical vibrating stimuli, therefore, such a periodic behavior exhibited by the shore sowbug has an endogenous feature in its nature. 4. The present writer is in the opinion that the periodic behavior accompanied with periodic movement of waves exhibited by the shore sowbug, may be one of the physiological adaptations in individual level to the inorganic waves, from thee. g., periodic movement of environmental elements, ecological viewpoint.