Thursday, 6 October 2016

spiral motion

“When a person loses his way in the forest or in snowstorms or fogs he goes around in circles as long as he keeps on moving, until in some way or other he finds his way again. The same is true of foxes, rabbits, antelopes,’ and doubtless other animals, when hard pressed in the chase. Going down lower in the scale of organisms, where there are only poorly developed guiding senses, as in some of the crustacea, or none at all as in the protozoa arid the flatworms, one finds these creatures going in circles all the time that they are in movement, hut with a ‘drift,’ making the path a loose helical spiral. In all these animals and, in fact, in all motile organisms whatsoever, there is a deep-seated spiralling mechanism which leads an animal to go in a series of circles of spiral form when there are no guiding senses, as in the lower organisms. or when the guiding senses do not function through fear or for other reasons, in the higher. A tendency to spiral locomotion is inherent in all moving organisms. An examination of biological literature shows, as is well known, that the lower animals : flagellates, ciliates, rotifers, and the marine larvae of echinoderms, molluscs, worms, and crustacea swim in spiral paths, as well as some of the zoospores of algae and a few spermatozoa. So many organisms, in fact, swim in spiral paths that the negative aspect of the question is the more practical form for purposes of investigation : Are there any motile organisms which do not move in spiral paths when guiding senses are absent or not functioning?”

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