Most sea stars are positively phototactic - they move towards light. While the ability to distinguish light and dark may help it find better habitat, most sea star's sense their environment primarily with a kind of smell - chemical reception. If the sea star detects a chemical signal from a prey animal, it moves in the direction of the arm receiving the strongest signal. In this way, it can relatively quickly find a prey animal. This material may be copied for use in student classroom projects and reports.
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