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Alignment of two classifications of the Monotremata

Echidnas, platypus – monotremes are amazing. They are also subject of an exploratory project to align two highly influential classifications of mammals using the Euler/X toolkit. Of course we are talking about:

  1. Mammal Species of the World, 3rd Edition. 2005.
  2. Mammal Species of the World, 2nd Edition. 1993. [not or no longer available on-line; which relates to our project’s aims.]

The respective 1993 & 2005 monotreme classifications were authored by Colin Groves. Thanks to MSW Editor DeeAnn Reeder for enthusiasm and support. Below is an abbreviated representation of how we aligned the two classifications. Most critically, in 1998 Zaglossus sec. Flannery & Groves (1998) was revised, and a new species (concept) Z. attenboroughi was added. Let us see what else changed..

Euler/X Toolkit Input: Table 1 – 1993 & 2005 concepts (name according to author).


Input Table 2 – Assembling each classification through parent/child relationships.


Input Table 3 – Articulations.  We need only 6 of these, and dared to assert them ourselves based on reconciling the two publications. == congruence, < proper inclusion, | exclusion. 16 + 17 == 6 means, in essence, that what used to be a single species-level concept 6 (Zaglossus bruijni sec. Groves 1993) got split into two narrower species-level concepts 16 + 17 (Z. bartoni sec. Groves 2005 and Z. bruijni sec. Groves 2005) which are jointly congruent with concept 6. Of the three input tables, only this third table requires (newly applied) taxonomic expertise.


 Now let us examine the Euler/X toolkit visualizations.

Input Visualization – Groves (1993) as yellow octagons and Groves (2005) as green rectangles.


Aligned Merge Taxonomy – in this visualization (which may be tweaked) – differently ranked concepts which otherwise refer to the congruent taxonomic entities due to monotypy (e.g., Ornithorhynchidae [7,18] => Ornithorhynchus [8,19] => Ornithorhynchus anatinus [9,20]) are visualized as clusters. For this visualization we used the polynomial encoding, with overlap shown. The red articulations represent newly inferred instances of inclusion. What this particular representation shows is that from a strict reasoning perspective, the new addition of Zaglossus attenboroughi sec. Groves (2005) (concept 2.15) “cascades up” to expand the taxonomic circumscriptions of the entailing genus (2.14), family (2.11), and ultimately the order (2.10). Alternative ways to represent this alignment are possible, however, and allow one to express that “Monotremata” sec. 1993/2005 are congruent (at least in an intensional, property-centered sense).


One order “done”, 28 to go?

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