The Bristol-Russia PTB Programme has the aim of dissecting the greatest mass extinction of all time, the Permo-Triassic boundary (PTB) event, which happened 252 million years ago. Through fieldwork in the redbeds of Late Permian and Early Triassic age, and analysis of palaeontological, sedimentological, and geochemical data, we seek to understand the environments before, during and after the mass extinction and how the plants and animals were wiped out and then recovered.
Most studies of the PTB event have focused on marine sections from many parts of the world. We hope to determine what happened on land. Our key aims are to find out:
- How do the timings and patterns of extinction on land compare with those in the sea? What were the global rates for loss of life on land, and how do these compare with the scale of the
- Were there associated climatic changes (in temperature, CO2 etc.), as indicated
by oxygen and carbon isotopes? Do the isotope curves match those from South Africa, and from
marine sections, thus implying a truly global scale change?
- What were the local environmental changes as indicated by sedimentology? Is there any evidence for global warming (e.g. aridity, desertification)?
- Is there evidence for massive plant die-off and soil stripping at the beginning of the Triassic? How did increased terrestrial erosion rates affect life in the sea?
- How did life on land respond to the crisis? What was the pattern of ecosystem collapse?
Is there evidence for ecological or taxonomic selectivity?
- What was the nature and timing of the post-extinction recovery through the Early and Mid
Triassic, in terms of rebuilding total diversity and rebuilding ecosystems? How do the Russian
data compare to South Africa and the marine realm?
- Was recovery a steady process of clade expansion, or was it fitful, with disaster taxa, and then more stable communities later?