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Related to phototactic: Phonotactic


The movement of an organism or a cell toward or away from a source of light.

pho′to·tac′tic (-tăk′tĭk) adj.
pho′to·tac′ti·cal·ly adv.


(ˌfəʊtəʊˈtæksɪs) or


(Biology) the movement of an entire organism in response to light
phototactic adj


(ˌfoʊ təˈtæk sɪs)

also pho′to•tax′y,

movement of an organism toward or away from a source of light.
pho`to•tac′tic (-ˈtæk tɪk) adj.
pho`to•tac′ti•cal•ly, adv.

phototaxis, phototaxy

the movement of an organism away from or toward a source of light. — phototactic, adj.
See also: Light
the movement of an organism away from or toward a source of light. — phototactic, adj.
See also: Motion
References in periodicals archive ?
halys individuals exhibit a positive phototactic response, orient themselves towards visual light sources, and show a distinct preference for white light over other colors in a laboratory setting (Leskey et al.
Consistent with this finding, adult Limulus exhibit a positive phototactic response when their MEs are illuminated with UV light but no response when their MEs are illuminated with visible light.
Environmental and physiological factors influencing phototactic flight of Bemisia tabaci.
If pelagic larvae are positively phototactic and become negatively phototactic during the settlement stage it is likely that light conditions would have had an influence on [?
As examples, paved surfaces (concrete, asphalt) directly remove habitat needed by ground-nesting bees and other insects; asphalt roads can induce misorientation of aquatic insects to polarised light, leading to futile oviposition on road surfaces; traffic can cause direct mortality; roadways may act as a barrier, isolating insect populations; light intensity in streets and buildings can attract phototactic insects from more natural areas and render them vulnerable to vertebrate predators; and 'heat islands' may affect development rates and tolerances of resident and adventive species.
Phototactic responses to ultraviolet and white light in various species of Collembola, including the eyeless species, Folsomia Candida.
Phototactic responses include movement towards or away from a light source.
Many aquatic insects are negatively phototactic and actively avoid light (Ward, 1992).
formosa) was positively phototactic in the absence of any chemical influence of its host mussel, Anodonta (now Pyganodon) cataracta, but exhibited negative phototaxis when tested in water containing extract of host gill tissue or in water from the mantle cavity of the host.
1997) Phosphoregulation of an inner dynein arm complex in Chlamydomonas reinhardtii is altered in phototactic mutant strains.