Diagnosis (biology)
In biology, diagnosis is the compilation of the most important characteristics of a group of living beings. In the description, especially in the first description of a species or a higher taxon , the distinguishing features are defined that distinguish these living beings from relatives. In zoology and botany , as well as in paleontology , the diagnostic features are usually listed in key words, whereby mainly morphological and anatomical properties are taken into account, which play a role for the classification in the biological systematics . In phylogenetic systematics, these are primarily apomorphies , i.e. derived features that have developed in the course of evolution compared to ancestors.
In contrast to an overall description of a living being, value is also placed on less conspicuous characteristics in the diagnosis, which are important for the differentiation from other groups. It also mentions the lack of traits that are present in closely related groups. (Diagnosis English : diagnosis ) an overall description can (English: description ) follow.
Historical development
Already Carl von Linné differentiated in his fundamental work Systema naturae , with which he established the biological nomenclature still valid today , between the descriptio (description) and the differentia specifica (specific distinctions). In the early days of describing living beings, the external differences between the individual species or higher taxa had to be large so that they could be perceived and described as specific groups. A differentiated diagnosis in addition to the description was therefore usually not necessary. Conversely, this approach often led to multiple descriptions if conspicuous features such as the coloration varied within a species without real characteristics of the species delimitation being given. For this reason, as early as the 19th century, short diagnoses with the essential characteristics were often placed before the detailed descriptions. Often they were written in Latin in order to achieve an international understanding using the Latin terms established in the sciences. The detailed description followed the diagnosis, but mostly in the respective national language.
Scientists often differ in terms of what a good diagnosis should involve and how clearly a new taxon needs to be differentiated from the known. It is not always clear in the diagnoses whether a property occurs only in the taxon described or whether it is a general characteristic of a larger group. The distinguishing features to other taxa can often be found in very different places in an initial description, e.g. B. in the comments, in the summary or discussion or in separate chapters that serve for comparison with one or more other groups of living beings. Some scientific journals, in which initial descriptions are published, pass on rules and recommendations to the authors who want to publish with them. A diagnosis is usually prescribed. It follows the suggested name for the new taxon and before the detailed description.
botany
In botany, the International Code of Nomenclature for Algae, Fungi and Plants requires a full description or diagnosis for valid initial descriptions of plants. The definition of diagnosis is given in article 32.2 of the Code:
"32.2. A diagnosis of a taxon is a statement of that which in the opinion of its author distinguishes the taxon from others. "
"32.2. A diagnosis of a taxon is a finding of what, in the author's opinion, distinguishes the taxon from others. "
zoology
In zoology, Article 13.1.1 of the International Rules for Zoological Nomenclature (ICZN) states that the publication of a new taxon must contain a verbal description or definition that takes into account the characteristics according to which the new taxon can be distinguished from others. The function of a diagnosis is discussed in more detail in Recommendation 13A.
"13A [...] an author should make clear his or her purpose to differentiate the taxon by including with it a diagnosis, that is to say, a summary of the characters that differentiate the new nominal taxon from related or similar taxa."
"13A. [...] an author should make his or her intention to differentiate the taxon clear by including a diagnosis, namely a summary of the characteristics that distinguish the new nominal taxon from related or similar taxa. "
Individual evidence
- ^ Carl von Linné : Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Vol. 1: Regnum animale. Editio decima, reformata. Laurentii Salvii, Stockholm 1758
- ↑ Author Notes ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. Information for authors of the journal Palaeontology and other publications of the Palaeontological Association (PDF, English; 323 kB)
- ↑ Nicholas J. Turland, JH Wiersema, FR Barrie, W. Greuter, DL Hawksworth, PS Herendeen, S. Knapp, W.-H. Kusber, D.-Z. Li, K. Marhold, TW May, J. McNeill, AM Monro, J. Prado, MJ Price, GF Smith (Eds.): International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017 (= Regnum Vegetabile. Volume 159). Koeltz Botanical Books, Glashütten 2018, ISBN 978-3-946583-16-5 , Article 38.2 (English, online , accessed August 18, 2018).
- ^ Richard L. Cifelli and Zofia Kielan − Jawrowska: Diagnosis: Differing interpretations of the ICZN. Acta Palaeontologica Polonica, 50, 3, pp. 650–652, 2005 full text (PDF, English; 76 kB)
