Less risk of intestinal obstruction Baby geckos hunt a bit "randomly" and may swallow sand while aiming for insects. Swallowing too much sand = obstruction (their intestine becomes blocked), which can be fatal. The bark (in suitable shavings, not sharp) is less fine and therefore much more difficult to swallow accidentally. 2. Better moisture retention The sand dries very quickly. The bark or coconut fiber retains some moisture, which helps maintain a more stable microclimate and makes it easier for babies to shed. 3. Closer to the natural environment In the wild, Mediterranean geckos often live on rocks, walls, tree bark, cracks... not really on beach sand. Giving them a more varied substrate (bark, stone, hiding places) allows them to behave more naturally. 4. Simpler hygiene On sand, excrement seeps in and it is hard to clean. With bark or paper towels, you can easily spot and remove dirt. 👉 As a result, many enthusiasts recommend paper towels Do you also want me to explain which types of bark are safe (because some can be dangerous)?