Evolution and environment in the late Silurian-early Devonian: the rise of the pteridophytes

Abstract

A brief review of the major advances since 1979 in Silurian and Devonian palaeobotany is followed by a preliminary report on a Gedinnian assemblage from the Welsh Borderland. This is dominated by rhyniopsids and includes several species of Cooksonia and Salopella . Spores have been isolated from a number of taxa. The assemblage is used to illustrate the problems of recognition and classification of early vascular plants. Parallel sedimentological and palaeogeographical studies permit speculation on the ecology and life histories of the plants that colonized the Old Red Continent. It is concluded that the lack of well preserved and independently dated assemblages from elsewhere in the world (an exception being the Baragwanathia flora of Australia) prevents the detection of any provincialism in the late Silurian and early Devonian and makes generalizations on the early history of vascular plants premature.