Shells reveal how ancient Sri Lankans adapted to rising seas

Associate Professor Patrick Faulkner is investigating how climate change and shifting sea levels from 24,000 to 1,000 years ago influenced human behaviour and migratory patterns on the southern coast of Sri Lanka.

His research, which featured in a 2024 journal article in Scientific Reports, focuses on Pathirajawela on the southern coast of Sri Lanka, which is a largely untapped archaeological resource.

By studying shell fragments, he can interpret changes in human behaviour over time, such as the shifts from economic use to ritual or symbolic use of certain shells. He also analyses the composition and variety of shell species to understand past diets and how people used those resources.

Associate Professor Faulkner holds a unique expertise in this area having spent the last 12 years working internationally on research projects in eastern Africa, Papua New Guinea, Oman and Jordan, and more recently in Sri Lanka as part of his ARC Future Fellowship.

“Working on shells allows me to understand the nature of human-environmental interactions on the coast (and other aquatic environments), or how people engaged with marine environments from inland locations, in a way that adds a different dimension to other forms of archaeological evidence,” said Associate Professor Faulkner.

Scientists know sea levels began to rise in Sri Lanka 24,000 years ago by studying ancient geological and biological evidence, such as marine fossils and sediment cores from locations that were once underwater. Techniques such as radiocarbon dating have been used to reconstruct past sea levels and identifying indicators of past shorelines, now found inland.