Clarify availability (fix issue #44)

04-introduction.md

@@ -4,7 +4,7 @@ Names of plant species are a foundation for further research on the ecology and
 
 Despite the importance of naming, and the many uses of a comprehensive taxonomic system, progress towards documenting and understanding plant diversity is challenged by the “taxonomic impediment”. This term was first introduced in 1976 and is a shorthand for the skills (and resources) gap in taxonomy [@taylor_submission_1976; @taylor_descriptive_1983]. Access to the necessary skills and resources is uneven, and when viewed globally actually mismatches the areas of greatest need: the most species-rich areas are often the most resource-poor [@meyer_multidimensional_2016]. 
 
-The naming of algae, fungi, and plants is governed by the International Code of Nomenclature for algae, fungi, and plants (hereafter the Code) [@turland_international_2018], which is revised every six years at the International Botanical Congress following proposals put forward by the botanical community [@knapp_stability_2004; @lindon_international_2020]. The Code has specific rules for publication of specific nomenclatural acts; unless these rules are followed (see Chapter IV and V of @turland_international_2018) names are not considered available for use. Nomenclatural acts referring to names of taxa include names of new taxa and  renaming of taxa (such as transfers to different genera or the establishment of a replacement name). Because nomenclatural acts must be published, they should theoretically be widely available for use by both taxonomic and downstream communities.
+The naming of algae, fungi, and plants is governed by the International Code of Nomenclature for algae, fungi, and plants (hereafter the Code) [@turland_international_2018], which is revised every six years at the International Botanical Congress following proposals put forward by the botanical community [@knapp_stability_2004; @lindon_international_2020]. The Code has specific rules for publication of specific nomenclatural acts; unless these rules are followed (see Chapter IV and V of @turland_international_2018) names are not considered code compliant and are not correctly available for use. Nomenclatural acts referring to names of taxa include names of new taxa and  renaming of taxa (such as transfers to different genera or the establishment of a replacement name). Because nomenclatural acts must be published, they should theoretically be widely available for use by both taxonomic and downstream communities.
 
 Names of taxa are associated with type materials, these are objects (often specimens) to which a name is attached and serve as a reference for future taxonomists. The type method is a relatively recent innovation, prior to 1958 the citation of a type as necessary for the publication of a nomenclatural act as defined above was not necessary (Art. 40, [@turland_international_2018]). The adoption of the type method in plant taxonomy means that there is an intimate connection between the names of plants and their type specimens in collections. The distribution of these preserved specimens has been influenced by colonial history, with comprehensive plant collections having been developed in the Global North, with just under 70% of  the almost 400 million herbarium specimens being housed in Europe and North America whilst the areas richest in species diversity are often located in the tropics [@paton_plant_2020; @thiers_worlds_2022]. Indeed, the enormous wealth of existing collections mean that many as yet unnamed taxa are already lodged in preserved collections, awaiting examination and description [@bebber_herbaria_2010].