INQUA Working Group on Data-Handling Methods

Newsletter 11: January 1994

RANDOM ACCESS COMPUTER KEYS (RACKs)

John H. McAndrews and Zicheng Yu
Department of Botany
Royal Ontario Museum
100 Queens Park
Toronto, Ontario M5S 2C6 Canada

E-mail:
docjock@utcs.utoronto.ca
yuzi@gpu.utcs.utoronto.ca

To make visual identifications of objects we resort to comparison with identified specimens, illustrations, descriptions and keys. In biology these keys commonly require choice between sequences of often subtle taxonomic characters. In contrast, random access keys permit selection of taxa using the more obvious characters of the unknown specimen. Random access keys take three forms: determinative tables for identifying minerals and wood, the edge-perforated card key illustrated in Faegri and Iversen (1964, p. 200) for identifying pollen grains, and the Random Access Computer Key (RACK).

A RACK is basically a two-dimensional array of characters versus taxa. You work the key by entering the most obvious characters in any order; taxa having these characters are immediately listed on the monitor. Our BASIC program was modified from Ogden and Mitchell (1990) to which Maher added an editor to ease making changes.

The type of RACK we describe is handy, easy to use and modify, inexpensive to operate, and it makes an excellent teaching device. Although the European and North American Pollen Databases are organized and available by random access, they are not easy to learn, and they require a user have Paradox©.

Our first RACK was designed to handle North American Pollen grains and spores, and we call it NAPKEY.BAS. It is a text-based key, and this was done to keep it simple and cheap. We are not competing with The South Pacific Pollen Atlas Project (Hope et al. 1992) or Cushing's (1991) Macintosh HyperStack© key SARI; both make use of screen graphics and are much more complex to set up and maintain. NAPKEY comes up with a screen that provides information and a few rules. The user then sees a screen like Fig. 1. There are 105 pollen/spore characters or character values grouped into nine menu categories. The main categories are shown in yellow capital letters. You can type a number or the letters N, R, or Q. If the number is between 1 and 105, the corresponding character item changes color, and the number of taxa with that character appears at the screen's upper left. You can see the names of these taxa by pressing the letter N. Normally one has several characters set simultaneously to reduce the number of possible taxa. If setting a character results in 0 taxa with that combination of characters, typing the number again prefixed with a minus sign turns the character off. If you want to reset everything and start again, touch the letter R. Touch Q to quit.

Figure 1. NAPKey Work Screen.

While it is not overly helpful to a student to see a list of taxon names, a lot of names indicates more grain characteristics are going to be needed to narrow down the possibilities. Whereas the microscope is best for deciding which taxon matches the unknown grain, RACKS should be used with a paper manual. NAPKEY uses McAndrews et al. (1973); when the taxa names appear, the user is given helpful comments as well as reference to figures showing the grain.

We have just completed a RACK for Hardwood (HWKEY.BAS) based on a table in Panshin and de Zeew (1970). Maher made a Rock and Mineral Key (MINKEY.BAS) based on Bowser et al. (1968), as well as one for identifying airplanes (AIRKEY.BAS) which refers to page illustrations in Montgomery and Foster (1984). The main screens of these RACKs are shown in Fig. 2. RACKs for tropical pollen, seeds and minnows are in progress.

Figure 2. HDKey, MINKey and AIRKey.

Because we are sure you are going to want to make a RACK for your own use, we have produced Generic RACK forms. They require no screen mapping to complete, and you can just fill in the blanks. The working screen comes in versions of two, three, four or five columns, together with editors for each type. Fewer columns are simpler and require fewer abbreviations. The group label on the generic RACKs is just another character with a CAPITALIZED name, and thus it is edited as a character.

A RACK is most useful when a user can add or delete taxa or change the characters associated with taxon. Lou Maher will discuss his EDITRACK program in the next article. These programs can run using QBASIC that come with DOS 5. You can get them by ftp from the INQUA File Boutique. They occur in the self-extracting file RACKS.EXE in directory: /pub/inqua on geology.wisc.edu (ftp 144.92.137.14).

References.

Bowser, C. J., Gates, R. M. and Archbald, D. 1968. Quick-Key Guide to Rocks and Minerals, Doubleday & Company, Inc., Garden City, NY.

Cushing, E.J. 1991. Sara: a HyperCard stack for describing and identifying spores and pollen grains. INQUA - Commission for the Study of the Holocene, Working Group on Data-Handling Methods Newsletter 6:1-3.

Faegri, K. and Iversen, Johs. 1964. Textbook of pollen analysis. Munksgaard, Copenhagen, 237 p.

Hope, G., Martinello, C. and Owen, J. 1992. Australian and Southwest Pacific pollen atlas project. INQUA - Commission for the Study of the Holocene, Working Group on Data-Handling Methods Newsletter 8:1-3.

McAndrews, J.H., Berti, A.A., and Norris, G. 1973. Key to the Quaternary pollen and spores of the Great Lakes region. Life Sci. Misc. Publ., Royal Ontario Museum, 61 p.

Montgomery, M.R. and Foster, G. 1984. A Field Guide to Airplanes, Houghton Mifflin Company, Boston, 212 p.

Panshin, A.J. and C. de Zeew. 1970. Textbook of Wood Technology, Vol. 1. 3rd edition. McGrawHill, New York (modified from Table 5-10).

Ogden, E.C. and R.S. Mitchel. 1990. Identifications of plants with fleshy fruits. New York State Museum Bulletin No. 467.

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