It’s hard to find fossil skin, but a rare discovery reveals clues about the evolution from water to land
Fossilized skin and other soft tissues are exceedingly rare, and it is only under special conditions that these rarest of fossils are preserved.
- Fossilized skin and other soft tissues are exceedingly rare, and it is only under special conditions that these rarest of fossils are preserved.
- Most skin is preserved as impressions in the rock, but under rare conditions and incalculable odds, a 3D fossil of the actual skin can form.
Fossilized skin
- The fossilized skin is so well preserved that its internal structures can be identified and is the oldest such fossil currently known.
- These early amniotes saw many evolutionary innovations that allowed them to adapt to the challenges of a fully terrestrial lifestyle, including several modifications to the epidermis, the outermost layer of skin.
Skin for living on land
- One of the biggest hurdles to living on land is water retention.
- The first tetrapods to lead largely terrestrial lives were amphibians whose skin was prone to drying out.
- As such, they remained bound to an aquatic environment and lived a semi-aquatic lifestyle for at least part of their lives.
- It was not until the evolution of reptiles, with their skin especially suited for water retention, that these pioneers were able to adopt fully terrestrial lifestyles.
A perfect cave system
- These exceptional fossils were discovered in a cave system near Richards Spur, Oklahoma.
- This cave system consists of expansive karst networks, which often appear as vertical fissures carved into surrounding limestone by water.
- Cave conditions are known to promote preservation of animal remains through desiccation, permeation by mineral rich ground water and burial by fine sediments.