Hope from history: how ancient reefs could hold clues to the future

17 February 2022

An international collaborative study led by the Museum of Tropical Queensland has revealed how the collapse of ancient reefs millions of years ago may hold clues to understanding more about the challenges faced by modern reefs today.

 

Scientists from Queensland, Poland and the US have produced a research paper exploring the largest reef systems on Earth which occurred occurred during the geologic period known as Devonian, approximately 385 million ago.

 

These huge reef systems, the remains of which can still be found around the world, collapsed during the Late Devonian mass extinction where three-quarters of marine species went extinct – including many key reef-builders.

 

Museum of Tropical Queensland and ARC Centre of Excellence for Coral Reef Studies at JCU (Coral CoE) Senior Curator of Corals Dr Tom Bridge said the research is significant because it helped identify characteristics of corals that made them more vulnerable to extinction, and what the consequences of the extinction were for marine ecosystems.

 

These ancient reefs were built primarily by an extinct group of corals, known as tabulate corals. Although they are not closely related to today’s corals, they possessed some similar traits to corals that build modern reefs.”

 

“The research shows that although some tabulate coral species survived the mass extinction, they were much less diverse and, crucially, were no longer capable of building reefs. Consequently, this extinction event had ecological consequences that lasted for tens of millions of years.” Dr Bridge said

Co-author of the study University of Warsaw coral palaeontologist and leading authority on tabulate corals, Dr Mikolaj Zapalski, said the paper examines the functional diversity of tabulate corals across a 35-million-year period and shows that what occurred across that timeline has some similarities to what scientists are seeing on reefs today.

“Reef growth over millions of years shows strong ‘boom and bust’ cycles, attributable to both changes in environmental conditions and biological factors. The extinction of these key reef-building coral species in the Late Devonian mass extinction was associated with rapid increases in temperature – which is also a well-known challenge facing modern coral reefs.”

 

“While there are important differences between the Devonian period and today; this study provides evidence that rapid temperature rises also led to the collapse of ancient reef systems, thus affecting the ecology of shallow marine ecosystems for millions of years afterwards.” Dr Zapalski said.

 

Queensland Museum Network CEO Dr Jim Thompson said now more than ever, history is showing us that we need to make significant changes to protect our reefs and the coral diversity that thrives there.

 

“International collaborations such as this are key in assisting our reefs through the challenges they face now and into the future,” Dr Thompson said.

 

The paper also examines the question of whether these ancient coral species were photosymbiotic, which enabled them to build reefs but also made them vulnerable to changes in climate - another similarity to modern reefs.


Paper: Tom C.L Bridge, Andrew H Baird, John M Pandolfi, Michael J McWilliam and Mikolaj K Zapalski Functional consequences of Palaeozoic reef collapse. Scientific Reports Article no 1386 (2022)

Media Contact: Andrea Hughes Marketing Coordinator | andrea.hughes@qm.qld.gov.au