A. INSECT DATABASES
In the Madang project, insect databases are routinely used as research tool for identification of (morpho) species, as well as medium of storage, preliminary analysis of field data, and teaching tool. The databases include digital pictures of whole insect specimens and morphological details, scanned drawings of outline of insect genitalia, text field for species diagnosis, taxonomic and ecological information, direct links to similar species and between developmental stages of the same species, as well as multiple ways of sorting species according to various taxonomic or ecological criteria. Spreadsheets used to input raw data are analyzed by a number of routines summarizing spatial and temporal distribution and host plant preferences for each species (sample of a template). The main advantages of using such powerful tools can be summarized as follows:
(1) Improved processing of insect material. Rather efficient and preliminary sorting can be achieved to prepare a sound material for further taxonomic analyses. Morphospecies which were never collected previously can be easily recognized and assigned. The assistants compare the digital pictures, read the species' diagnosis, compare drawings of genitalia and examine insect specimens in reference collections, all at the same time. A typical set-up in our laboratory includes a computer screen facing a good stereomicroscope equipped with fiber optics.
(2) Improved management of rather considerable and complex insect data. Our databases hold basically all the insect data resulting from the project and are fully relational. Various preliminary analyses can be performed with the click of a few buttons.
(3) Improved training and teaching of insect parataxonomists. Since the display of the digital pictures is quasi immediate, the databases are constantly used as a sort of mega "flip-books" by the parataxonomists. In doing so, they quickly learn to recognize particular families, group of species or morphospecies, and quickly grasp essentials of taxonomy. The value of our databases as a teaching tool is also enhanced by a glossary of entomological terms, characterized by relevant text and illustrations.
Such databases appear particularly useful in the context of ecological projects dealing with complex data stemming from multi-species communities. Typically, in these situations, the number of species being examined is rather limited (as compared to large-scale taxonomic surveys, for example) and, concurrently, the number of specimens collected is rather high. As such, our tool differs markedly from other databases more taxonomically orientated and less amenable to management of considerable field data, such as DELTA, CABIKEY, Platypus, etc. It is more similar to Biota, but since it has been developed specifically for our insect herbivore study, it is much simpler. It is therefore easier to use (important for parataxonomists), but also needs to be re-programmed to accommodate any changes in the data structure or project design. Other interesting databases include BioLink, Specify, Lucid and Ecoport.
Technical information
The databases are being developed by Richard
Pyle of Bishop Museum, using the software Microsoft Access
7.0. Since Access comes as a standard with the Windows operating
system of many DOS-based computers, the databases can easily run
on a variety of configurations. We split the databases according
to taxa, thus allowing convenient back-up on Iomega ZIP
cartridges of 100 MB. Typically, databases hold information about
250 species per 100 MB size, including two images per species.
B. DIGITAL PHOTOGRAPHY
In Madang, we use a SONY video camera for shooting digital pictures, but other configurations are also possible with similar results (for example, a FUJIX digital camera in Guyana). The video camera is hooked to a TV screen, which allow convenient setting of light sources and of the insect specimen. The screen is also helpful for teaching purposes. The main advantages of using digital photography over a more conventional setting involving regular photography and a slide scanner is the speed to which the final pictures can be included in the databases. This is particularly important when continuously collecting a rather high number of specimens, which need to be quickly assigned, and with no easy way to process quickly slide or negative films.
The assistants are also trained to work with digital techniques, i.e. to develop the ability of shooting high quality pictures of insect specimens and retouching efficiently these pictures using adequate computer software. This is particularly important because a trade-off is needed between the quality of the pictures and the amount of memory space that must be allocated to them.
We developed a processing system for live caterpillars in which they are anaesthetised with CO2 to reduce mobility and to allow shooting of optimal colour pictures. After recovering, the caterpillars are reared to the adult stage, pictures of the adults are shot, thus allowing matching between juvenile and adult specimens.
Our methods using digital photography and
databases are described in a greater detail in:
Basset, Y., Novotny, V., Miller, S. E. & Pyle, R. (2000)
Quantifying biodiversity: experiences with parataxonomists and
digital photography in New Guinea and Guyana. BioScience 50,
899-908. Click here for
abstract.