Diversity, ecology and functional characteristics of Medullosa fern seeds

The project focuses on a specific group of seed plants from the late Palaeozoic era, the Medullosaceae. These fossil plants are known primarily from the tropical forests of the North American Carboniferous basins, but were also widespread in the seasonally dry forests of the early Permian. Little is currently known about the early Permian representatives: what they looked like and what evolutionary adaptations they underwent in response to the changing environmental conditions at the Permian–Carboniferous boundary.

In the Petrified Forest of Chemnitz, a forest ecosystem preserved by volcanic ash around 291 million years ago, the three-dimensional preservation of almost complete plants allows for a detailed reconstruction of the Medullosaceae, including the habitat in which they thrived. In the DFG project, the taxonomy of these plants is to be reassessed on the basis of extensive collection material in order to better understand their diversity. For the relevant taxa, we aim to generate models of complete plants using systematically collected fossils, which will allow conclusions to be drawn about growth form and architecture.

A second objective is to characterise the palaeoecology of medullose plants in as much detail as possible, ranging from the 3D-preserved root systems to morphometric analyses of the fern-like fronds. A third objective of the project is to model physiological processes in these plants using anatomical parameters. To this end, new approaches for quantifying the water-conducting capacity of fossil plants are to be developed and applied using computer simulations.

Ultimately, this should make it possible to better quantify material cycles and atmospheric environmental parameters in Permian fossil forests. This is particularly interesting for the early Permian, as a severe glaciation phase on Earth was coming to an end at that time. It is assumed that medullose plants played a significant role in the carbon and water cycles of these seasonally dry ecosystems, based on their presumed high biomass production and evaporation rates.

Ultimately, the aim is to make material cycles and atmospheric environmental parameters in Permian fossil forests more quantifiable. This is particularly interesting for the early Permian, as a severe glaciation phase on Earth was coming to an end at that time. It is assumed that medullose plants played a significant role in the carbon and water cycles of these seasonally dry ecosystems, based on their presumed high biomass production and evaporation rates.