An international team of researchers from Jilin University in China and the University of Oklahoma in the United States has identified what is now considered the oldest preserved skin sample in the fossil record. The specimen dates to the Paleozoic era and belonged to one of the earliest reptiles to roam the planet, roughly 289 million years ago. The find is documented in a reputable scientific journal and represents a significant milestone in the study of ancient life and vertebrate skin evolution.
Paleontologists describe the fossil as extending the timeline by about 21 million years beyond similar discoveries, highlighting the remarkable preservation of the epidermis, the outermost layer of skin. Its texture and structure show clear similarities to modern crocodile skin, offering researchers a rare window into how early land-dwelling vertebrates may have adapted their protective coverings to terrestrial environments.
The fossil was discovered within the Richards Spur limestone cave system in Oklahoma, a site known for its exceptional preservation conditions that can trap delicate tissues. The cave environment allowed natural oils and resins to seep into the remains, acting as slow, efficient preservatives that prevented typical decay and helped maintain the integrity of soft tissues that rarely fossilize.
Experts say that this discovery will illuminate the broader narrative of skin evolution across terrestrial vertebrates, a lineage that ultimately contributed to major innovations such as the development of feathers in birds and fur or hair in mammals. By tracing the changes in skin texture, thickness, and organization over deep time, scientists gain insight into the pressures and adaptations that shaped a wide range of life on land.
Previous discussions about early vertebrate skin often center on harder, bony elements or gross skeletal remains. This new skin specimen adds a complementary perspective, showing how soft tissues can record environmental interactions, physiological strategies, and evolutionary steps that are less visible in bones alone. The discovery underscores the value of exceptional fossil sites and meticulous preparation in revealing secrets buried in ancient pigments and tissues. [1] [Attribution to the study authors]