Numerical taxonomy of some bacteria isolated from antarctic and tropical seawaters.

Pfister, Robert M. (Lamont Geological Observatory, Palisades, N.Y.), and Paul R. Burkholder. Numerical taxonomy of some bacteria isolated from Antarctic and tropical seawaters. J. Bacteriol. 90:863-872. 1965.-Microorganisms from Antarctic seas and from tropical waters near Puerto Rico were examined with a series of morphological, physiological, and biochemical tests. The results of these analyses were coded on punch cards, and similarity matrices were computed with a program for an IBM 1620 computer. When the matrix was reordered by use of the single-linkage technique, and the results were plotted with four symbols for different per cent similarity ranges, nine groups of microorganisms were revealed. The data suggest that organisms occurring in different areas of the open ocean may be profitably studied with standardized computer techniques.