coprolitesfossilized

Coprolites are fossilized feces produced by animals at various times in Earth’s history. The word combines Greek kopros, meaning dung, and lithos, meaning stone. They form when fecal matter is rapidly buried and mineralized, preserving evidence of diet and digestion. Coprolites may result from phosphate replacement, silica or calcite infill, or preservation by carbonization or iron minerals, producing durable, stone-like objects.

Contents within coprolites provide direct clues to ancient feeding, including plant material, seeds, pollen, bone fragments, scales, and shells. In some cases, microfossils or chemical residues enable taxonomic or ecological inferences, though many specimens cannot be confidently attributed to a specific producer. Coprolites thus contribute to reconstructions of past food webs, foraging behavior, and environmental conditions.

Preservation tends to be favored in sedimentary settings with rapid burial and mineral-rich waters, such as river floodplains, coal beds, and marine deposits. They occur across a wide range of sizes, from millimeters to several centimeters, and occasionally larger specimens are found. Dating is typically indirect, relying on the age of surrounding rocks or associated fossils, though some analyses use isotopic or mineralogical evidence to constrain timing.

Common sources of coprolites include a variety of vertebrates, notably dinosaurs and marine reptiles, as well as sharks and other fish, although attribution can be challenging without corroborating remains. As fossils, coprolites provide a unique window into the biology and ecosystems of ancient life.