+A sign stimulus is a simple, often exaggerated feature in an animal's environment that triggers a specific, innate behavior. This crucial concept in [Ethology](/wiki/ethology) explains how a distinct cue, like a red patch, acts as a [Releaser](/wiki/releaser), prompting a predictable response without prior learning.
+## See also
+- [Fixed Action Pattern](/wiki/fixed_action_pattern)
+- [Supernormal Stimulus](/wiki/supernormal_stimulus)
+- [Innate Behavior](/wiki/innate_behavior)