Networks of highly branched stigmarian rootlets developed on the first giant trees
Coal swamps were the carbon burial factories of the Carboniferous period, forming huge coal deposits and driving climate cooling. The Carboniferous forests were also home to the first giant (>50 m) trees to grow on the planet. These trees were anchored by a unique structure termed a stigmarian system, which is hypothesized to represent a leafy shoot modified to function as a root. Here, we report the discovery of the complex, highly branched rootlet structure of these trees. Our findings demonstrate that rootlet architecture is conserved from the giant extinct trees of the Carboniferous to the small extant herbs of today’s flora (Isoetes).
Reconstruction of stigmarian root systems with highly branched systems of rootlets by Rosemary Wise, Botanical Artist.
Collaborators, supporting organisations and funders
This work was undertaken in collaboration with Christopher M. Berry. School of Earth and Ocean Sciences, Cardiff University.
We would like to thank The John Muir Trust, The National Trust, Natural England, the Scourie Estate, (All for help and permission to collect Isoetes plants). Oxford University Museum of Natural History, Oxford University Herbaria, London Natural History Museum, British Geological Survey, and University of Manchester, Manchester Museum (All for access and permission to fossil material).
This research was supported by a Biotechnology and Biological Sciences Research Council (BBSRC) Doctoral Training Partnership Scholarship to Alexander (Sandy) Hetherington and a European Research Council Advanced Grant awarded to Professor Liam Dolan.