A possible biological component of the explanation for the lack of substantial coal formation on Antarctica between the Late Jurassic and Late Cretaceous in hypothesised. Forcing a process-based terrestrial biogeochemistry model with climate model simulations for three successive intervals of the Mesozoic [Late Jurassic (150 Ma), mid-Cretaceous (100 Ma) and Late Cretaceous (65 Ma)>, predicts the establishment of productive terrestrial ecosystems with substantial soil carbon pools throughout the land surface of Antarctica between 150 and 65 million years ago. Sensitivity analyses indicate the annual land surface hydrological budget of Antarctica 150--65 Ma was largely balanced due to the effects of canopy transpiration on soil moisture. Post-depositional erosion and tectonic setting must have played an important role in determining coal preservation on the continent. However, the model results indicate that an active vegetated land surface precluded the preservation of the substantial soil organic carbon inputs by minimising the potential for anaerobic preservation (i.e. water logging). ¿ 2000 American Geophysical Union