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How does the law of priority determine the accepted scientific name of a taxon?

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A nautilus mollusk with a spiral, brown-and-white striped shell and numerous white tentacles extending from its soft body, set against a dark background. — species A nautilus (*Nautilus*) floating in the water column of the ocean.

The law of priority is a fundamental principle in biological nomenclature used to ensure stability and consistency when naming organisms. Under this rule, the first name that was validly published and meets the requirements of the relevant international code for a given taxon is considered the correct, accepted name.12

Any other names subsequently published for that same taxon are relegated to the status of synonyms. This system prevents confusion by establishing a clear chronological precedence for scientific naming. While international codes for botany, zoology, and microbiology may differ in specific procedural details, they all uphold this core requirement to maintain a standardized taxonomic record. If a taxonomist's understanding of a taxon's status changes, the valid name may be updated, but the law of priority remains the primary mechanism for determining which name takes precedence among those previously published.21