A comparison of intuitive and objective interpretations of Miocene plant assemblages from north Bohemia

Abstract

An extensive corpus of semi-quantitatively described geobotanical analyses from the early Miocene of north Bohemia has been examined by parametrical and non-parametrical multivariate statistical methods. The results of these analyses have been compared with traditional geobotanical interpretations that are based on uniformitarian assumptions. The statistical analyses show that there are patterns of relationships inherent in the raw geobotanical analyses that are very similar to the traditional interpretations; but the statistical analyses define seventeen groups where tradition recognises eight. The objective picture from the statistical study, however, throws a fresh perspective on the familiar evidence and implies that montane, colline, and riparian forest associations—often sub-divided on edaphic lines-can be recognised in addition to the lowland marsh ecologies implicit in a major brown coal deposit. The present-day ecological patterns recognisable in ecosystems more than twenty million years old suggest that most of the components retained their ecological preferences throughout this time. The statistical analyses offer fresh insights into aspects of the processes transporting the specimens to their place of burial. The success of the statistical analyses indicates that the methods used are potentially capable of identifying ecological associations in older geological systems.