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Movement of a motile cell or organism in response to the direction of water currents.



the property of certain lower plants (myxomycetous plasmodia), unicellular animals (flagellates, infusorians), and cells (spermatozoa) to move in a direction opposite to the current of a fluid.

References in periodicals archive ?
There is evidence that fish use it for prey detection, predator avoidance, intraspecific communication, schooling, object discrimination, entrainment, and rheotaxis (Bleckmann, 1993, 1994; Montgomery, et al., 1997).
Therefore, each population may be simultaneously employing characteristics of both an odor-gated rheotaxis (Dusenbery, 1992) and a chemo-tropotaxis (Payne et al., 1986).
Gastropods may use odor-guided rheotaxis and move upstream after detection of attractive chemical cues until they are able to detect and follow a concentration gradient (Croll 1983).
All showed positive rheotaxis, in that crawling always was oriented in the upstream direction.
The effects of flow speed.--Flow speed has a dual effect on olfactory search by influencing plume dispersal and by providing a directional cue for the navigating organism via rheotaxis (Bossert and Wilson 1963, Bell and Kramer 1979, Brown and Rittschof 1984, Weissburg and Zimmer-Faust 1993).
There has to be some flow to serve as the directional cue which will trigger the positive rheotaxis on the juvenile, so that they move upstream.
They were frequently observed crawling directly upstream (positive rheotaxis).
For example, striped jack show strong phototaxis from 3.5 mm TL and rheotaxis from 4.5 mm TL (Masuda and Tsukamoto, 1996).
The lateral line functions in surface feeding, rheotaxis, localization of underwater objects, and subsurface prey detection (1).
(1997) provided experimental evidence that differential weighting, caused by the presence of spicules at the posterior end in some larvae, is correlated with positive geotaxis and rheotaxis.
To run the experiments, the system was set with similar flow rates of clean seawater entering each side of the choice chamber, thus reducing any confounding effects of rheotaxis. The test animal was placed in the middle of the drainage plate outlet and allowed to acclimate for 1 mm.