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We assessed the effects of an outdoor education programme (Tihoi) with no access to electronic media among 14 year-old boys. We compared creative thinking, socio-emotional wellbeing, and materialism with their peers attending regular classes at their normal school. Students at both locations were assessed in the second week of term and after 15 weeks. Boys in the Tihoi programme outperformed those in regular classes on a creative thinking task at both time points. Although the Tihoi group initially had lower scores on some well-being measures, they had small but significant improvements in wellbeing at 15 weeks, which were not observed among those attending normal school. No differences were observed for materialism. A programme of outdoor activity and reduced media exposure may improve creative thinking and wellbeing in adolescents. Encouraging adolescents to replace indoor time with outdoor activities is unlikely to cause persistent psychological harm and may be beneficial.

Palacrodon, a near-crown stem reptile, is known from several Triassic sites across the globe, and is easily recognized by its dentition characterized by labiolingually expanded molariform teeth coupled with acrodont tooth implantation. Here we explore the nature of tooth implantation and attachment in specimens of Palacrodon from South Africa and Arizona, U.S.A. using µCT. We note the presence of unusual ridges located underneath the tooth crowns in Palacrodon browni. Such ridges are not present in specimens from Arizona, which warrants the naming of a new species P. parkeri. We conducted a broad survey of internal tooth morphology across extant and extinct pan-reptiles (n = 212), and we conclude that homologous ridges like those we observe in P. browni are not present in any other species of reptile. As such, our ability to determine the function of the ridges is limited, though we hypothesize it is related to tooth attachment via unmineralized soft tissues. [ABSTRACT FROM AUTHOR]

Large-bodied temnospondyl amphibians were the dominant predators in non-marine aquatic ecosystems from the Carboniferous to the Middle Triassic. In the Permian-aged lower Beaufort Group of the main Karoo Basin, South Africa, temnospondyls are represented exclusively by the family Rhinesuchidae and are well represented by body fossils, whereas trace fossils are scarce. Accordingly, most interpretations of the behaviour of this family are based on skeletal morphology and histological data. Here we document the sedimentology and palaeontology of a late Permian palaeosurface situated immediately below the palaeoshoreline of the Ecca Sea (transition from the Ecca Group to the Beaufort Group) near the town of Estcourt in KwaZulu-Natal Province. The surface preserves numerous ichnofossils, including tetrapod footprints and fish swim-trails, but most striking are seven body impressions and associated swim trails that we attribute to a medium-sized (~1.9 m long) rhinesuchid temnospondyl. These provide valuable insight into the behaviour of these animals. The sinuous shape of some of the traces suggest that the tracemaker swam with continuous sub-undulatory propulsion of the tail. [ABSTRACT FROM AUTHOR]

The Triassic dicynodont Sangusaurus is poorly known because the holotype of the first species to be described (S. edentatus from Zambia) is fragmentary, and the description of the second species (S. parringtonii from Tanzania) is extremely brief. Nevertheless, the genus has played a role in Triassic biostratigraphy by linking the Ntawere Formation and the Manda Beds. Here, we redescribe Sangusaurus, including a new, nearly complete skull from Tanzania. The incomplete holotype of S. edentatus results in few characters diagnosing the genus. The skull of S. parringtonii, however, is highly autapomorphic. The snout is telescoped, with only a thin strip of frontals separating the nasals and the parietals. The external surfaces of the premaxilla, the maxillae, the nasals, and the prefrontals are extremely rugose; a sharp median crest extends from the premaxilla to the frontals, terminating in a thickened boss. The occiput is broader than the skull is long, and the adductor fossa on the squamosal is nearly vertical. Our phylogenetic analysis shows that Sangusaurus is not a kannemeyeriid but instead is a stahleckeriid. The feeding system of Sangusaurus emphasizes an orthal jaw motion. The articular surfaces of the jaw joint form a single posteroventrally sloping surface; translating the quadrate and the articular results in a primarily orthal movement of the jaw symphysis. The internal and external jaw adductors provide a strong, dorsally-directed component to the power stroke. Adductor mechanical advantage is similar to Stahleckeria, but Sangusaurus likely had a stronger transverse component of jaw movement because of the very lateral placement of M. adductor mandibulae externus lateralis. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Angielczyk, K. D., P. J. Hancox, and A. Nabavizadeh. 2018. A redescription of the Triassic kannemeyeriiform dicynodont Sangusaurus (Therapsida, Anomodontia), with an analysis of its feeding system; pp. 189-227 in C. A. Sidor and S. J. Nesbitt (eds.), Vertebrate and Climatic Evolution in the Triassic Rift Basins of Tanzania and Zambia. Society of Vertebrate Paleontology Memoir 17. Journal of Vertebrate Paleontology 37(6, Supplement). [ABSTRACT FROM AUTHOR]

Knowledge of Late Permian biodiversity patterns, following the end-Guadalupian crisis, is still in its infancy, since most recent studies have focused on the end-Permian biotic crisis. The palynological record of southern Africa, however, reveals major climatic changes during the Late Permian. Here we report new palynological data from eastern Tete Province of Mozambique, documenting the change from cool to warm temperate climates during the Lopingian. This prominent climate signal was also detected recently in other depositional environments elsewhere in southern Africa, and thus enables interregional temporal correlations. [ABSTRACT FROM AUTHOR]

A new species of the erythrosuchid archosauriform reptile Garjainia Ochev, 1958 is described on the basis of disarticulated but abundant and well-preserved cranial and postcranial material from the late Early Triassic (late Olenekian) Subzone A of the Cynognathus Assemblage Zone of the Burgersdorp Formation (Beaufort Group) of the Karoo Basin of South Africa. The new species, G. madiba, differs from its unique congener, G. prima from the late Olenekian of European Russia, most notably in having large bony bosses on the lateral surfaces of the jugals and postorbitals. The new species also has more teeth and a proportionately longer postacetabular process of the ilium than G. prima. Analysis of G. madiba bone histology reveals thick compact cortices comprised of highly vascularized, rapidly forming fibro-lamellar bone tissue, similar to Erythrosuchus africanus from Subzone B of the Cynognathus Assemblage Zone. The most notable differences between the two taxa are the predominance of a radiating vascular network and presence of annuli in the limb bones of G. madiba. These features indicate rapid growth rates, consistent with data for many other Triassic archosauriforms, but also a high degree of developmental plasticity as growth remained flexible. The diagnoses of Garjainia and of Erythrosuchidae are addressed and revised. Garjainia madiba is the geologically oldest erythrosuchid known from the Southern Hemisphere, and demonstrates that erythrosuchids achieved a cosmopolitan biogeographical distribution by the end of the Early Triassic, within five million years of the end-Permian mass extinction event. It provides new insights into the diversity of the Subzone A vertebrate assemblage, which partially fills a major gap between classic ‘faunal’ assemblages from the older Lystrosaurus Assemblage Zone (earliest Triassic) and the younger Subzone B of the Cynognathus Assemblage Zone (early Middle Triassic). [ABSTRACT FROM AUTHOR]

Extensive research on the rocks of the Karoo Supergroup has shown that this sequence, which contains an unsurpassed record of Permian-Jurassic tetrapods, records a largely unbroken stratigraphic succession from 300 Ma to 180 Ma. This Gondwanan succession was deposited in a changing environmental setting reflecting glacial marine through deltaic to fluvial and aeolian desert conditions. The contact between the Ecca and Beaufort Groups (at the top of the Waterford Formation of the Ecca Group) in the southern and western Karoo represents a change in depositional environment from a subaqueous to a subaerial delta plain. By contrast, the Waterford Formation has not yet been recognised in the south-eastern Karoo Basin, which might imply that a major unconformity is present between the Fort Brown Formation of the Ecca Group, deposited in a prodelta environment, and the overlying fluvially deposited Koonap Formation of the Beaufort Group. From careful documentation of lithofacies and sedimentological data, it can be demonstrated that the Waterford Formation is indeed present in the south-eastern part of the basin and that no major unconformity is present - a fact that has implications for the mapping of Karoo rocks in the Eastern Cape Province of South Africa, for understanding the depositional environment of 'reptilian' fossils from the lowermost Beaufort in this part of the Karoo basin, and for basin development models. [ABSTRACT FROM AUTHOR]

The Late Triassic to Early Jurassic Molteno, Elliot and Clarens formations of the uppermost part of the Karoo Supergroup in the main Karoo Basin of South Africa form a distinct tectono-sedimentary sequence. A major problem with the modeling of this part of the Karoo basinal fill is that the nature of the Molteno-Elliot contact is poorly understood. Previously the contact has been defined on a mix of lithological and palaeontological criteria, and has been considered to be gradational or transitional in nature, with the Elliot considered the distal equivalent of the upper Molteno Formation. Recent field investigations demonstrate that the boundary can be defined on lithologic changes, including the gross and internal geometries of the sandstone units and contained lithofacies associations, the presence/absence of coal seams and paleosols, and on palaeocurrent patterns, sandstone composition and grain-size variations. This boundary represents a regional unconformity throughout the basin and the recognition of this cryptic second order sequence boundary invalidates previous interpretations of an interfingering stratigraphic relationship between the two formations. Stacking patterns in the upper Karoo Supergroup, and the tectonic framework of their development, suggest that the southern margin of the Kaapvaal Craton acted as a regional control on sequence development during Late Triassic -- Early Jurassic times. [ABSTRACT FROM AUTHOR]

Based on regional palaeocurrent pattern analysis and petrographic studies, the Late Triassic-Early Jurassic Elliot Formation (Karoo Supergroup, South Africa) is divisible into a Lower and an Upper Elliot Formation. Laterally, along a north-south section, the lower unit displays both changes in the sediment supply pattern and petrological composition, whereas the upper unit lacks significant petrological variations. A break in sedimentation took place after the deposition of the Lower Elliot Formation, and a regional subaerial unconformity is detected between the Lower and Upper Elliot formations. This unconformity is emphasized by marked differences in the sedimentological and palaeontological composition of the deposits below and above the surface. Prevailing northerly sediment supply patterns of the Lower Elliot Formation are replaced by mainly easterly-northeasterly transportation directions in the Upper Elliot Formation, trends which were mentioned, but not accounted for by earlier researchers of the Late Triassic-Early Jurassic Elliot Formation. Simultaneously with the reorganization of the sediment supply patterns, the origin of the sandstones also shifted from recycled-orogen provenance, to a transitional continental source situated between craton interior and basement uplift provenances. This paper presents the contrast in palaeocurrent trends and sandstone composition across this surface, and reports, for the first time, the basin-wide presence of outsized quartzite pebbles and boulders, sourced from the Cape Fold Belt. [ABSTRACT FROM AUTHOR]

The integrated results of a facies analysis and provenance study of the Late Trissic to Early Jurassic Elliot Formation (Karoo Supergroup) provide some new insights into the development of the main Karoo foreland system of South Africa. Based on changes in the fluvial style, palaeocurrent pattern, provenance, isopach trends and fossil content, a regional lithostratigraphic subdivision of the Elliot Formation is proposed. In addition, the boundary between the Lower and Upper Elliot formations appears to be a second order sequence boundary. This unconformity was probably generated by the last stage of orogenic loading of the Cape Fold Belt, which interrupted the overall, first order orogenic unloading of the system, suggesting that tetonically controlled flexural subsidence existed in the main Karoo Basin until at least the end of Triassic. The magnitude of this pre-Upper Elliot Formation suggest that the first stages of inversion from a compressional to extensional tectonic regime began only in the Early Jurrasic. [ABSTRACT FROM AUTHOR]

A proximal caudal vertebra from the upper Elliot Formation (Early Jurassic) of the main Karoo Basin is identified as a sauropod dinosaur more derived than basal forms such as Antetonitrus and Blikanasaurus from the lower Elliot Formation (Late Triassic). The caudal displays an ambiguous autapomorphy with the Early-Middle Jurassic Vulcanodon from Zimbabwe and may be closely re- lated to that genus. This is the first record of a sauropod dinosaur from the upper Elliot Formation and indicates that the sauropodomorph fauna of the Massospondylus Range Zone is more diverse than previously appreciated. In particular, it demonstrates that large, robust sauropodomorphs are not restricted to the lower Elliot Formation. [ABSTRACT FROM AUTHOR]

Terrestrial Triassic assemblages are an important component of the heritage of Argentina, particularly because of their diverse record of fossil vertebrates. Triassic basins from western Argentina have a good representation of therapsids, a lineage that includes a series of stem extinct groups plus crown Mammalia. Because of their diversity and abundance, non-mammaliaform cynodonts are the most conspicuous therapsids in the Argentinean Triassic. Cynodonts have been intensively researched in Argentina since the 1960s and continue to provide key advances in the understanding of the evolution and biology of the lineage. Here we offer a summary of Triassic Argentinean non-mammaliaform cynodonts, presenting a historical context of research on this group, and highlighting seminal contributions of Triassic Argentinean cynodonts to the global knowledge of the group. To provide a Gondwanan context we review the cynodont record in the two other places where the lineage is best represented: Brazil and southern Africa (including Madagascar), highlighting commonalities in the Argentinean record with these places. Considering the important role of non-mammaliaform cynodonts in the interpretation of the origin of mammals, we provide a historical account on the contribution of Argentinean, and Gondwanan, cynodonts to the understanding of this topic. This is supplemented with a summary of the progression of phylogenetic ideas and hypotheses for all non-mammaliaform cynodonts and for the most prolific subgroups represented in western Gondwana. • Western Gondwana has 61 Triassic cynodont species: 40 in South America, 21 in Africa. • Non-mammaliaform cynodonts from Argentina have been known for seventy-seven years. • Traversodontid cynodonts are best documented in Argentina. • Triassic cynodonts evidence faunal connections between South America and Africa. • Western Gondwana cynodonts are crucial to understand the early evolution of mammals. [ABSTRACT FROM AUTHOR]

Background: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic., Principal Findings: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic) of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative., Conclusions: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.