In a groundbreaking discovery, researchers from Ohio State University have shattered the long-held belief that complex organic molecules cannot survive fossilization.

The revelation comes from the examination of remains of crinoids, aquatic sea creatures that lived around 350 million years ago, in Ohio, Indiana, and Iowa. These fascinating creatures, also known as “sea lilies,” were found to have retained organic compounds sealed within their fossilized skeletons.

Crinoids, with their feathery arms and plant-like appearance, were buried alive during storms in the Carboniferous Period, when vast inland seas covered North America. Rapid burial and isolation from the water by layers of sediment allowed their porous skeletons to gradually fill with minerals. Importantly, some of the pores containing organic molecules remained intact and sealed.

The discovery challenges the assumption that complex organic molecules couldn’t withstand the fossilization process. The identified molecules are aromatic compounds called quinones, found in both modern crinoids and other animals. Quinones can serve various functions, such as pigments or toxins to deter predators.

The unique aspect of this discovery lies in the fact that these organic molecules were found inside specific, complete fossils rather than being scattered fragments. The molecules, identified as quinones, provide valuable insights into the biology of the individual animals whose remains were tested.

The study was led by Christina O’Malley, who noticed color differences among crinoid species preserved side by side in the same rock. The fossils displayed various colors, such as light bluish-gray, dark gray, and creamy white, distinct from the color of the rock they were buried in.

O’Malley isolated the molecules by grinding small bits of fossil and dissolving them, then analyzed them using a gas chromatograph mass spectrometer. The molecules were identified as quinones, similar to those found in modern crinoids.

The well-preserved state of the fossils, their unique skeletal structure, and the specific conditions of their burial contributed to the retention of these ancient organic molecules. The findings challenge preconceptions about the preservation of organic material and open new avenues for understanding ancient ecosystems.

While these molecules may not replace DNA in defining evolutionary relationships, they offer a unique glimpse into the biology of ancient species. Further research aims to identify the exact type of quinone molecules present and explore the depth of information they can provide about these intriguing sea creatures from Earth’s distant past.