Sprecher
Beschreibung
The Early Eocene Climatic Optimum (EECO; c.53–49 Ma) is one of Earth’s hottest times marked by high global temperatures that allowed forests similar to modern tropical regions to thrive within the polar circles. These polar ecosystems were subject to an extremely seasonal light regime and atmospheric CO2 levels vastly different to any modern forests. Although the taxonomic composition of many ancient polar floras is well established, their forest structure at high latitudes remains largely unresolved.
The fossil plant assemblage of the Macquarie Harbour Formation (53–50 Ma) in Tasmania, southeastern Australia, was situated near the south polar circle (65–70°S). While Tasmania represented the last land bridge between Australia and Antarctica, its flora likely expanded along Antarctica’s margin.
Recent excavations have resulted in hundreds of leaf compressions that received detailed systematic study, thus offering a window into the extinct southern polar forest biome. We utilise this flora to study the vertical and horizontal forest structure (stratification, canopy openness) by using geochemical and morphological proxies for canopy structure as well as additional lines of evidence from systematic studies. We present the first results and methodological approaches to characterise this vegetation within the southern polar forest biome.