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Published: 2022-12-20

Putting the cart before the horse: SeqCode’s attempt to solve systematics issues with changes to nomenclature

Biosecurity Surveillance & Incursion Investigation Plant Health Team, Ministry for Primary Industries, Christchurch, New Zealand
Research & Collections, Natural History Museum of Los Angeles County, Los Angeles, California, USA
Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
Division of Invertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, USA
Systematics nomenclature prokaryotic nomenclatural codes nomina DNA sequences taxa explanatory hypotheses


This opinion paper examines the recent proposal for a new nomenclatural code for prokaryotes (SeqCode). It addresses four problematic issues: (1) epistemological—failure of the SeqCode to acknowledge taxa as explanatory hypotheses, (2) conceptual—designating as a name-bearer a coded section of the genome of an organism, (3) operational—changing nomenclatural procedure as a means of resolving systematic challenges, and (4) political (policy)—SeqCode developed independent in opposition to the International Committee on Systematics of Prokaryotes (ICSP). Each of these matters should be alarms to the scientific community as the SeqCode proposal embodies many potentially negative consequences that would dramatically hinder systematics (science) and nomenclature (a tool in science) in other groups of organisms, e.g., animals, plants, fungi, if analogous proposals were sought.


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