Assessing taxon names in palynology (II): indices to quantify use of names

Abstract

A major and recurrent issue in nomenclature and taxonomy is synonymy and the occurrence of competing names for a taxon. Formal proposals for conservation, protection, or rejection of names are a painstaking but necessary work, which for extant plants, often requires consulting the frequency of use of competing names in floras. In palaeopalynology, such information can be gathered by tedious consultation of the literature or by working with palaeopalynological databases, which provide easily accessible quantitative data on how frequently each given taxon name is used. Here, we show that such information can be employed not only for taxonomic revisions in plant microfossils, but also to calculate three new simple metrics, i.e. Citation Share (CS), Citation Rate (CR), and Establishment Index (EI), and quantify how widespread the use of a name is on its own, or in comparison to potentially competing name(s). Using three case studies, we demonstrate how our proposed metrics can easily be used to present how the use of a name of a taxon changed over the decades, especially for competing names. Independently of the study question, our proposed metrics provide a fast overview of popularity of names and abundance of the respective taxa in species inventories (CS and CR), and a concise compound metric to represent the standing of a name for competing names today (EI). Their advantage is that they encode information that would otherwise require rather lengthy enumerations and space-consuming visual representations. They are therefore an effective tool to represent data in a short and concise way to clarify cumbersome taxonomical and nomenclatural problems, and can support informed proposals for either conservation, protection or rejection, which are typically very limited in space for the respective argument.

Keywords:

• taxonomy
• Palynodata
• John Williams Index of Palaeopalynology
• databases
• Citation Share
• Citation Rate
• Establishment Index

Acknowledgements

We are very grateful to Stephen Stukins (Natural History Museum London) and Niall Paterson (CASP, Cambridge) for sharing photocopies of the JWIP cards. We thank Wolfram M. Kürschner (University Oslo) for supervising JG’s PhD thesis, bringing her in contact with the topic and problems of taxonomy and nomenclature. Furthermore, we thank Maria Schauer (Freie Universität Berlin) for her diligent help with compiling part of the dataset. We sincerely thank Nicholas Turland (Botanical Garden and Botanical Museum Berlin) for his inspiring insights on taxonomy and nomenclature that informed this study and for commenting and editing on Code related topics of this manuscript. We thank the editor Jim Riding (British Geological Survey), who assisted in solving copyright questions about potential reprint of Orłowska-Zwolińska’s images and for efficiently helping with technical issues of this side-by-side submission. Additionally, we thank Annette Götz and a second anonymous reviewer for their constructive criticism and suggestions that significantly improved this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.