Response of Late Carboniferous and Early Permian plant communities to climate change

Late Carboniferous and Early Permian strata record the transition from a co ld interval in Earth history, characterized by the repeated periods of glac iation and deglaciation of the southern pole, to a warm-climate interval. C onsequently, this time period is the best available analogue to the Recent in which to study patterns of vegetational response, both to glacial-interg lacial oscillation and to the appearance of warm climate. Carboniferous wet land ecosystems were dominated by spore-producing plants and early gymnospe rmous seed plants. Global climate changes, largely drying, forced vegetatio nal changes, resulting in a change to a seed plant-dominated world, beginni ng first at high latitudes during the Carboniferous, reaching the tropics n ear the Permo-Carboniferous boundary. For most of this time plant assemblag es were very conservative in their composition. Change in the dominant vege tation was generally a rapid process, which suggests that environmental thr esholds were crossed, and involved little mixing of elements from the wet a nd dry floras.