CONCLUSION

The morphology, orientation and abundance of the horizontal, regularly-oriented structures suggest a biogenic origin, and a likely social insect-like (termitic?) architect. The ethological reason for the preferred alignment of these biogenic structures of the Clarens Formation remains unknown to date. The dearth of similar modern features leads to speculation as to the exact functional interpretation of the traces, as well as the role of their tracemakers in the Early Jurassic ecosystem. Nonetheless, these findings, together with the other Early Jurassic palaeontological and sedimentological records of southern Africa, contain important clues regarding changes in the depositional environment that were most likely related to episodic variations in climate as well as intermittent sedimentation rates. The recurrence of moisture indicating biogenic and sedimentary structures in the Lower Jurassic aeolian successions in this part of Gondwana may be used to enhance the resolution Early Jurassic global climate models. In particular, with improved stratigraphic and geochronological studies, the strongly oriented biogenic structures that show ethological pattern adaptations to changing ecological parameters may prove to be valuable constraints in reconstructing the duration and periodicity of Early Jurassic climate changes. Finally, it is hoped that this morphologic description detailing their physical appearance, geological context and associated trace fossils will aid the recognition of similar ancient structures, and advance the quest for identifying modern organisms capable of producing similar structures.