An Australian-led study used prehistoric feces to uncover how molecular fossilization occurs, revealing new insights into what ancient animals ate, the world they lived in and what happened after they died.

The study, published in the journal Geobiology, examined 300-million-year-old fossilized droppings, or "coprolites," mostly from the Mazon Creek fossil site in the U.S., according to a statement released Friday by Australia's Curtin University.

The coprolites were already known to contain cholesterol derivatives, which is strong evidence of a meat-based diet. The new research explored how those delicate molecular traces were preserved and survived the ravages of time.

Usually, soft tissues are fossilized due to the presence of phosphate minerals. However, scientists from Australia, the U.S., Sweden and Germany found that the molecules in their samples were preserved because tiny grains of iron carbonate scattered throughout the fossil acted like microscopic time capsules.

"Fossils don't just preserve the shapes of long-extinct creatures; they can also hold chemical traces of life," said study lead Madison Tripp, adjunct research fellow at Curtin's School of Earth and Planetary Sciences.

"It's a bit like discovering a treasure chest, in this instance phosphate, but the real gold is stashed in the pebbles nearby," Tripp said, adding that the findings deepen scientists' understanding of molecular preservation, crucial to gaining insights into the ancient world.

"Carbonate minerals have been quietly preserving biological information throughout Earth's history," said Curtin University Professor Kliti Grice, adding expanded analysis of diverse fossils spanning different species, environments and eras confirmed consistent mineral-molecule preservation patterns.

Understanding which minerals best preserve ancient biomolecules lets scientists target fossil searches more effectively, focusing on conditions that increase the chances of finding molecular clues about ancient life, Grice said.

The researchers said the findings could help build a richer picture of past ecosystems, including their diets, interactions and decomposition processes.

"It brings prehistoric worlds to life in molecular detail," Grice said.

(Cover: A graphic illustrating the fossilization processes. /VCG)