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Fabio d'Alessi
the database
the logic behind our database and the S.I. code

Document Revision 1.0
First Edited October, 1st, 2005
Reads : 3400
1. Genera and Species
2. Entities
3. Linking entities to genera and species
4. The first release of the database (2003-4)
5. Expanding the view - the second release (2005)
6. Guessing Engine
7. database interfaces

Without entering into too much detail, genera and species are the lower hierarchic levels in which botanists and zoologists subdivide living beings, following a method established by Linnaeus in his books (Species Plantarum, Systema Naturae, etc.) in 1753-1759. According to this method, animals, plants, bacteria and every living being can be properly put in relationship with the others following a pyramidal hierarchy of different levels (top to bottom: Kingdom, Phylum, Class, Order, Family, Genus and Species). Several variations of this method have evolved in centuries, but the basic principle still remains valid.

Unfortunately, according to the "weight" given to different concepts and features, different authors can build (and usually do) different hierarchies, with subtle, yet sometimes incompatible differences from previous classifications.

Because of this (as well as other reasons) in the centuries hundreds of authors have published different descriptions, articles, classifications, revisions and counter-revisions of the same plants or animals, generating an endless plethora of names, of which some are valid, others are synonyms and others are regarded as invalid. In some cases the nomenclature is evolving at such a pace that it is not uncommon to find a plant with tens of names. The confusion arising from this is clear.

This problem is present in the Stapeliad world as well, and it is well evident since the very beginning when some authors, talking about these plants, still put them in a family Asclepiadaceae while others, following a more recent approach, merge them into the Apocynaceae family, and treat asclepiads as the subfamily Asclepiadoideae. It is probably not so wrong to say that every species of asclepiad has been given at least two or three different names in its botanical history.

Notwithstanding this, the "botanic names" of plants prove to be an invaluable resource to help people speaking different languages and living in different countries refer to a specific plant, therefore every tool or database dealing with stapeliads has to take into account the existing scientific nomenclature, with all its problems, synonims and neverending changes.

At the moment a very good resource that keeps track of all published scientific plant names (as well as the names of the authors that published them, and the publication where they published it and when) is the I.P.N.I. (the International Plant Name Index). has a direct interface to the full nomenclatural data present at IPNI, and heavily refers to it.

After speaking about nomenclature, botanic names, genera and species, let's briefly talk about another issue: entities.

You will find the word "entity" in the database and pages quite often. An "entity" is nothing magic, it is just a word we use to refer to a single plant or group of plants with very high similarity between them. It is not a species - the definition of "species" is something so delicate and fought on that we do prefer to leave that to hi-tec scientists, botanists and philosophers.

An entity is just a plant or group of plants with extreme similarity and consistence among them.

Whenever you walk in habitat and stump into a population of plants, you will see they display remarkable similarities in the stem, growth, flower shape and colors. The population might be scattered in a few mile area or spreading in a vast continuous area. We regard this population as an "entity". If you then walk to a totally different place, you might found another group of plants of the same "species", but displaying a different flower shape and color - a different entity.

An "entity" is not defined in a theoretical and philosophical way - tries to be extremely "practical", so an "entity" is just a useful way to distinguish different plants, even when they are the same species.

You can think at the SI code which you will find throughout the whole website as the "entity" code. I can't remember if Loukie and I chose S.I. as an acronym for Stapeliads.Info or for Specimen Id - possibly for both.

The database is built around the two above ideas. There is a nomenclature database keeping track of genera, species, publications, dates and authors (in other words a database of ideas), and there is a specimen database with photographs, notes and observations of real plants in habitat and cultivation (in other words a database of things).

The way a certain entity (material thing) is linked to a scientific name (ideal concept) is the determination.

Entity (real plant)DeterminationGenus/Species (concept)
A determination is an assessment made by a knowledgeable botanist, enthusiast or specialist, which states that according to him a certain entity pertains to that genus/species. The database allows more determinations for each single entity, when there is no general agreement on a single determination. The database will be smart enough to treat that entity as if it were two different species (or more). Determinations can be modified, added, deleted, and the database internally rearranges entities and names accordingly.

Working on the schema we just described, I have begun coding the database in my spare time between 2003 and 2004.

Initially the idea was to build a "photography" database, like many around the net in these days. It became immediately evident that if we were using a single "photo" database, with a scientific name attached to a photo, there would have been many problems with synonyms, spelling errors and name changes.

Because of this I opted for a wider approach: I split the "name" part from the "image" part - downloaded the Asclepiadaceae data from IPNI (authors, plant names, publication names and dates) and arranged them in a "nomenclatural database", built up a database of pictures and habitat/cultivation notes (and arranged them in a "specimen database") and then built up a set of "determinations" in order to link this or that specimen to this or that published plant name.

Around mid 2004 this is how the database looked like. We had something like 5-600 photographs with notes and words from various cultivators and explorers arranged in a specimen database, plus a small part of the IPNI Asclepiadaceae family data snapshot, with just the names and author abbreviations. A simple relation table was linking this or that photo to this or that name.

Functional, simple, sleek. But, honestly, not groundbreaking.

Simple, functional, sleek. But not groundbreaking.

The database was doing what we wanted it to do : you were looking for Stapelia gigantea and it was reporting you the author abbreviated name, when it was published and where - and it was displaying you the photos of the specimens currently determined as Stapelia gigantea.

Good. But... enough?

I started playing with the database while Loukie was going on uploading pictures from South Africa to Italy night after night and after a while it became evident that "Stapelia L. (Sp.Pl.1753)" was not enough for me. Stapelia what? Stapelia where? Why Stapelia? - IPNI does not give these answers since it focuses on pure nomenclature and publication data, but these are quite common questions.

Notes on Genera and Species. The first thing I did was to expand the nomenclatural database with two additional note-tables, one for genera and one for species and lower level taxa (species, subspecies, forms, varieties and so on). Table notes, strictly hand edited, contain information not available on IPNI, as, for example, distribution area, cultivation notes, historical notes, name etymologies and so on. All these notes, which add great detail to a taxonomical entry, make up an "annotation database", linked to the IPNI nomenclature backbone.

IPNI extension. And at the end, no, I didn't like that "L." and that "Sp.Pl.". Yes, it's true - everywhere in every book you find them - but - in many many years I have never found a place where to read author and publication names in their plain full format. Sure we all know that that "L." stands for Linnaeus, but I would like to know how many know exactly what the "N" in N.E.Br. stands for, when he lived and so on. This is why I reconnected to IPNI and this time I downloaded the full set of data on plant names, on the publications and their extensive descriptions, on the plant authors, their full names and dates. This greatly enlarged the Nomenclatural Database.

Synonyms. One of the things that causes more headaches to newbies (but not only) is keeping track of valid names, invalid names and, especially, synonyms according to the various authors (one frequent scenario is this: author A uses a valid species name; author B treats that as a synonym for another species of the same genus; author C cancels the whole genus as invalid - and so on). IPNI keeps track of only a minor part of these synonyms. The remaining ones usually are hidden at the end of monographies and books. One of the tasks to be performed is building a complex synonym index on to be embedded in the nomenclatural database.
-> As of October 2005, this is the only part of the structure which is not finished yet.

Reports. While the first three improvements were mainly made to the nomenclatural database, a fourth improvement was made to the entity database. What I wanted was each entity contents to be not only written by the site administrators, but I wanted also to leave to the users, visitors, botanists and enthusiasts an open door for their own contributions: images, cultivation notes, curiosities. This is where the concept of "report" came from. A report is a set of notes (with or without an image) attached to an entity. Notes can be added by anyone and, this way, the general knowledge about that single specimen is not something statically put on the net by the authors of the site but something growing with the contributions of every user.

Field Numbers. Last, in the attempt to concentrate as much information as possible on each single entity, I also started to code a "field number database" in which further information about locality, collecting data, habitat notes and other can be sent in.

This is how the database looks like now.

As you can see the two main "trunks" of information are still the nomenclatural database and the specimen (or entity) database - just, now things have evolved and each trunk is made up of several different parts.

A last drawing depicting an example entity will simplify things and show how data is organized inside this structure.
As you can see, there is not a direct link between an entity and a scientific name. This is exactly what we wanted, as it is close to what happens in habitat: plants do exists on their owns and do not know their "own" name. They simply get associated to this or that name according to this or that author. A particular improvement added to the second release of the structure was the programming of a "guessing" algorithm on user queries - after all, even if botanists like to be extremely correct on plant names, simple enthusiasts often find it difficult to remember the right spelling of Rhytidocaulon or other similar names. Wouldn't it be beautiful if the database were able to understand what a user is looking for even if he didn't digit it particularly well?

Good news: it is.

If you don't believe me try accessing PAN and search for "peudolito migurtino" and see it for yourself.

Given the huge amount of data and linking tables built one thing that became evident playing with the second release of the database was the need for more "ways" to access to the data. The classical interface Loukie and I were using, infact, was not enough - it was squeezing out only a minor part of the new structure capability.

Because of this I tried building alternative ways to access to the data contained in the server. Right now these are the tools which interface with the structure:

  • the SI-Database : this was the first interface built. Initially studied as a simple image browser now it is the main way to access the database from an "entity" point of view. The focus is being put on the entity. The interface browses through available SI entities, reports and images.

  • P.A.N. (Publications, Authors and Names) : as the SI-Database approaches the structure from an entity point of view, PAN takes the opposite direction and approaches the structure from the IPNI point of view - the focus is put on scientific names, publications and author names and data.

  • SI Code Browser : a small but helpful tool to have a quicker access to the SI database. Browsing entities through the SI database interface can be clumsy and slow sometimes - with the Code Browser it is easier to see many entities per time - if this is what the user seeks. A simple lookup index.

  • Image Console : yet another way to access the specimen data - but this time not from a botanical nomenclature point of view nor from an entity one. The Image Console browses through all images submitted and associated reports and SI entities. The focus here is put on the images and the entity phototypes.

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