Botanical systematics 1950-2000: change, progress, or both?

Biosystematics, the study of variation patterns and evolution at the specie s level and below, flourished In the 1950s. Higher evolutionary level studi es, however, were stalled because there was no convincing way of hypothesis ing relationships. Phenetic systematics developed in the late 1950s as a cr itique of both the goals and methods of evolutionary systematics, its own g oals being those earlier stated by Gilmour (1940: 472, emphasis in original ): "A natural classification is that grouping which endeavours to utilise a ll the attributes of the individuals under consideration, and hence is usef ul for a very wide range of purposes". Phenetic computer-assisted analyses of data became popular. Nevertheless, many systematists were specifically i nterested in phylogenies. By the late 1970s several methods that produced h ypotheses of phylogeny were in use; they emphasised the possession of share d, derived characters. Since then variants of parsimony-based Hennigan anal yses have remained popular. With the influx of molecular data-a flood after 1990-and the development of methods that estimated aspects of support for branches of phylogenetic trees, a radical overhaul of higher-level relation ships got underway. Analyses of species-level patterns of variation were le ss popular during much of this period, and the process of description of sp ecies has remained largely unchanged. However, computer-based interactive k eys and multi-purpose descriptive databases may fundamentally affect this a rea of our business. During the last 50 years some kinds of systematic work have become highly cooperative and systematics as a whole is a much more u nified discipline, even as some more traditional areas of botanical systema tics seem largely static if not in regress.