Paleocene-Eocene Thermal Maximum (PETM)

Sand tiger shark teeth

Sand tiger shark (Odontaspis robusta) teeth from the Early Eocene rocks of Abbey Wood, Kent

Principal Investigators

Project summary

  • Focus: Studying the response of organisms to the PETM
  • Funding: The Natural History Museum

This project investigates the response of organisms to the Paleocene-Eocene Thermal Maximum (PETM), the most rapid and significant climatic warming pulse of the past 65 million years.

We are studying molluscs and cartilaginous fish (sharks and rays) from extensive fossil deposits in north-west Europe to answer these questions:

  • Did patterns of extinction and evolution change?
  • Did overall levels of biodiversity change, and if so, over what interval of time?
  • What was the effect of the PETM on the ecology and structure of shallow marine communities?

Coastal ecosystems around the world are increasingly fragile and ecologically degraded, but many communities rely on them for a wide range of ecosystem services. We hope that documenting the response of organisms to the PETM will help us to predict the result of current global warming in these habitats.


The PETM occurred around 55.8 million years ago. Global temperatures rose by 6°C, leading to an increase in atmospheric CO2 levels comparable to the rate of current anthropogenic warming.

Some organisms were unable to adapt to rapidly changing environmental conditions and became extinct. These included:

  • bottom-dwelling deep-sea organisms
  • open-ocean plankton
  • terrestrial mammals

Little is known about the response of shallow-water marine organisms to the PETM and how coastal ecosystems themselves may have changed. 

Related information

Origins, evolution and futures

We study the Earth's origins and environment, and the evolution of life.

Invertebrate and plant palaeobiology research

We are investigating the origins and evolution of these diverse fossil groups.

Palaeontology collections

The geographic, stratigraphic and historical coverage of fossils in the collection make it globally important.