One giant clam contains a month-by-month diary of the Great Barrier Reef’s climate 200 years ago

By Bohao Dong, Research Assistant, ARC Centre of Excellence for Indigenous and Environmental Histories and Futures, The University of Melbourne
Amy Prendergast, Associate Professor in The School of Geography, Earth and Atmospheric Sciences and Chief Investigator for the ARC Centre of Excellence for Indigenous and Environmental Histories and Futures, The University of Melbourne
Sean Ulm, Director, ARC Centre of Excellence for Indigenous and Environmental Histories and Futures, James Cook University

When you swim through the azure waters of the Great Barrier Reef, there is one entity on the seafloor that’s almost impossible to miss: the giant clam. Its huge, fluted shell frames a soft mantle shimmering with electric blue, green and gold.

As the world’s largest living bivalve, Tridacna gigas can reach 1.2 metres, weigh more than 200 kilograms and live for over a century. Across their long lives, these clams record their daily life in their shells, creating an autobiographical shell diary.

Read complete article

~	Register to vote for the winner of the Vitae Three Minute Thesis competition 2026 – supported by The Conversation

~	More land, better life? South African farming study asks if that’s the road to rural development

~	Child malnutrition is one of Africa’s biggest health challenges: food aid is only part of the solution

~	Senegal’s Youth Olympics legacy: who pays after the Games?

~	“I lost a friend following an unsafe abortion in Malawi”

~	Millions of adults in England have high blood pressure without knowing it – so why are free pharmacy checks not solving the problem?

~	Brain stimulation could reshape how you learn new skills

~	Pollen season: new map of South Africa’s allergy hotspots gives you time to prepare

~	After five years of war, how do Ukrainian small businesses survive?

~	The joy of song: where songbirds came from and why we should listen to them