Tetrapod origins of small burrows from the Permian of Southwest Poland?

This paper reports on early Permian continental burrows from Poland. The in situ orientation of the burrows, their size, morphology, and wall margin sculpture suggest that they could have been excavated with limbs of small tetrapods. The burrow-makers likely used a technique similar to that applied by modern amphibians and reptiles with sprawled limb posture. Putative small-sized tetrapod tracks are preserved on laminae parting surfaces within the burrow-casting sediments. Their presence may suggest that some small-sized tetrapods utilized the preexisting, abandoned shelters. The purported fossorial behaviours could increase the environmental fitness of tetrapods inhabiting the environment of the circa equatorial early Permian Pangaea.