Plinian Core: A Data Specification for Species Pages in the Real World
Authors: Pando Francisco , Mora-Cross Maria , Plata Camila , Vargas Manuel , Martínez-Sagarra Gloria 
Published: August 2024

Plinian Core (PliC), a standard in development by a Biodiversity Information Standards (TDWG) task group, is a set of vocabulary terms that can be used to describe different aspects of biological species information, including all kinds of properties or traits related to taxa—biological and non-biological. PliC incorporates terms pertaining to descriptions, legal aspects, conservation, management, uses, demographics, nomenclature, or related resources (Plinian Core Task Group 2021).
Having a data specification is just a small part of what it takes to prepare and publish species information. The specification provides a structured way to describe species-related data, ensuring consistency and interoperability across different platforms and databases. Different aspects of Plinian Core and its development have been presented in the past (Pando 2018; Pando et al. 2022). In this contribution, we shift the focus out of the specification itself, to other key aspects of species information dissemination.
Plinian Core has been already put to use in various real-world scenarios. Here we select three examples to present the most significant lessons learned:

Cross-Nature Project

This project developed a Resource Description Framework for PliC to create an ontology-based endpoint for the Species Information System of the Spanish Ministry for the Environment (EIDOS). It provides a structured framework for describing and integrating species data following the Linked Open Data principles. The system provides information for over 85,000 species.

Biodiversity Catalogue of SiB Colombia

This national catalogue provides information on the natural history, conservation, threats, and biology of Colombian species. Aimed at a broad audience, it maintains scientific rigor while being accessible to anyone interested in Colombia's biodiversity. PliC has been essential in this endeavor, enabling the inclusion of both highly structured technical information and rich, engaging textual descriptions for over 6,000 species.

EncicloVida

Developed by CONABIO, EncicloVida aims to publicize the Mexican biodiversity. The platform integrates biological species information on more than 114,000 species of plants, animals, fungi, bacteria, and protozoa that CONABIO has gathered through the National Information System on Biodiversity (SNIB) in collaboration with Mexican researchers.
These implementations are based on the PliC Core abstract Model that is expressed as an XML Schema definitiion (XSD), and the supporting documentation is provided in the PliC Wiki.
Automatic aggregation of species pages is challenging and often ineffective as differences in taxonomic treatments, or in local populations (either biological or otherwise: threat status, laws and regulations, etc.) frequently create inconsistencies or even render false information. Conversely, sharing a standard across projects offers immediate benefits, such as consistency of navigation and information, or the facility for sharing software solutions.
Plinian Core terms, vocabularies and structure have been developed in collaboration with implementers and in response to real-world demands. That has resulted in a set of fairly large data specifications, but one flexible and easy to understand by domain experts who may not work comfortably with more technical approaches.
Each implementation puts emphasis on different aspects, applying different levels of granularity depending on the requirements. This is done by choosing between "unstructured" terms (for low granularity) or the "atomized classes'' (for highly structured information).
For instance, dispersal information can be recorded as a text block ("DispersalUnstructured") or using a set of specific terms: Purpose, DispersalMeans, StructureDisperse ("DispersalAtomized").
PliC reuses a number of terms from other standards (see Borrowed terms section) following a well-established best practice. Using XSD files as a basis, we link borrowed terms from external sources to their original specifications, which were also expressed as XSD files. This should provide consistency and reliability. However, this has proven to be problematic to maintain and validate, as links are broken and files changed. To keep the PliC XSD file valid, we opted for maintaining local copies of the XSD of the respective reused standards.
We also aim to present some current and future developments of PliC, especially in the context of the Living Atlases community. Thus, we will explore other elements involved in sharing species information such as the Global Biodiversity Information Facility's Integrated Publishing Toolkit extensions, SPARQL Endpoints, Frictionless Data Packages, Research Object-Crates, and integration with Atlas of Living Australia modules.