Pearse Vicki Buchsbaum
Biol Bull. 1974 Dec;147(3):630-640. doi: 10.2307/1540746.
The sea anemone Anthopleura elegantissima, with and without endosymbiotic zooxanthellae, was tested for evidence of phototactic behavior. Anemones with zooxanthellae always displayed phototaxis, either positive or negative depending on the experimental light intensity and the light intensity of the habitat from which the animals were taken. Anemones without zooxanthellae-even those that had previously harbored zooxanthellae and that were genetically identical clone-mates of phototactic individuals-never displayed phototaxis, appearing completely indifferent to light and shade. The results indicate that phototaxis in this sea anemone depends directly on the presence of its symbiotic algae. It is suggested that the flexible phototactic behavior of the anemone may play an important role in favorably regulating the amount of light to which the zooxanthellae are exposed.
对有无内共生虫黄藻的太平洋海葵进行了趋光行为证据的测试。有虫黄藻的海葵总是表现出趋光性，根据实验光强度和动物所采集栖息地的光强度，趋光性有正有负。没有虫黄藻的海葵——即使是那些以前曾有过虫黄藻且与有趋光行为个体基因相同的克隆体——从未表现出趋光性，对光和暗完全无动于衷。结果表明，这种海葵的趋光性直接取决于其共生藻类的存在。有人认为，海葵灵活的趋光行为可能在有利地调节虫黄藻所暴露的光量方面发挥重要作用。
