Half humanoid (head and torso) and half fish or dolphin-like (an aquatic tail instead of legs) mermaids are traditionally folklore legends as are mermen and other related merfolk. Modern fiction has extended the traditional image to include more dramatic appearances - elaborate tails, fins, gills, scales, feathers - and living beyond the limits of Earth's waters. While mermaid stories continue in fantastic fantasy tales, they further appear in modern science fiction works.
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