Toe fringes are a key innovation for sand dwelling lizards, and the relationship between toe fringe function and substrate properties is helpful in understanding the adaptation of lizards to sand dune environments. We tested the sand burial performance of Phrynocephalus mystaceus on different sand substrates with toe fringe manipulation, with the aim of assessing whether the function of the toe fringes shifts under different substrate properties, especially in highly mobile substrates. The sand burial performance of P. mystaceus was influenced by substrate properties in relation to the toe fringe states of the lizard. After removal of the bilateral toe fringes, the sand burial ability score of P. mystaceus was significantly higher on sand substrates below 100 mesh than on native sand substrates. As the angle of stability of the substrate properties decreased, the sand burial performance of the lizard was even better after the bilateral toe fringes were removed. The results of the LASSO model and the path analysis model showed that the stability angle provided the opposite effect on sand burial performance in different toe fringe states. These results further suggest that the sand burial function of toe fringes may not be suitable for highly mobile sand substrates. It remains to be tested further whether the function of toe fringes is more important for running on sand.

中文翻译：

---

脚趾边缘对于蜥蜴埋在高度流动的沙子中重要吗？


脚趾边缘是沙栖蜥蜴的一项关键创新，脚趾边缘功能与基质特性之间的关系有助于了解蜥蜴对沙丘环境的适应。我们通过脚趾边缘操作测试了沙蜥在不同沙质基质上的沙埋性能，目的是评估脚趾边缘的功能在不同基质特性下，特别是在高度移动的基质中是否发生变化。 P. mystaceus 的沙埋性能受到与蜥蜴脚趾边缘状态相关的基质特性的影响。去除双侧脚趾边缘后，P. mystaceus 在 100 目以下的沙基质上的沙埋能力得分显着高于天然沙基质。随着基底性能稳定角的降低，去除双侧趾须后蜥蜴的埋沙性能甚至更好。 LASSO模型和路径分析模型的结果表明，不同趾缘状态下稳定角对埋砂性能的影响相反。这些结果进一步表明，脚趾边缘的沙埋功能可能不适合高度流动的沙基质。脚趾边缘的功能对于沙地跑步是否更重要，还有待进一步检验。