An architecture for electronic field guides

People who classify and identify things based on their observable or deducible properties (called “characters” by biologists) can benefit from databases and keys that assist them in naming a specimen. This paper discusses our approach to generating an identification tool based on the field guide concept. Our software accepts character lists either expressed as XML (which biologists rarely provide knowingly—although most databases can now export in XML) or via ODBC connections to the data author’s relational database. The software then produces an Electronic Field Guide (EFG) implemented as a collection of Java servlets. The resulting guide answers queries made locally to a backend, or to Internet data sources via http, and returns XML. If, however, the query client requires HTML (e.g., if the EFG is responding to a human-centric browser interface that we or the remote application provides), or if some specialized XML is required, then the EFG forwards the XML to a servlet that applies an XSLT transformation to provide the look and feel that the client application requires. We compare our approach to the architecture of other taxon identification tools. Finally, we discuss how we combine this service with other biodiversity data services on the web to make integrated applications.