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Estimates of deep-time biodiversity typically rely on statistical methods to mitigate the impacts of sampling biases in the fossil record. However, these methods are limited by the spatial and temporal scale of the underlying data. Here, we use a spatially explicit mechanistic model, based on neutral theory, to test hypotheses of early tetrapod diversity change during the late Carboniferous and early Permian, critical intervals for the diversification of vertebrate life on land. Our simulations suggest that apparent increases in early tetrapod diversity were not driven by local endemism following the ‘Carboniferous Rainforest Collapse’. Instead, changes in face-value diversity can be explained by variation in sampling intensity through time. Our results further demonstrate the importance of accounting for sampling biases in analyses of the fossil record and highlight the vast potential of mechanistic models, including neutral models, for testing hypotheses in palaeobiology.

We describe two partial dentaries of mammals from the Middle Jurassic of Scotland. They belong to the early cladotherian Palaeoxonodon ooliticus. These dentaries comprise the first specimen of P. ooliticus ever found – although its significance was initially unrecognised so it remained undescribed until now – and the most recently discovered specimen, found during fieldwork in 2017. The new specimen preserves part of the coronoid process of the dentary, previously unknown for P. ooliticus, demonstrating the presence of a deep masseteric fossa, with a prominent crest enclosing the fossa anteriorly, and a masseteric foramen, located in the masseteric fossa on the buccal surface of the dentary. On the lingual surface, the mandibular foramen is offset from the Meckel’s sulcus, and positioned below the alveolar plane. These morphologies allow an updated analysis of the phylogenetic position of P. ooliticus, confirming a sister-taxa relationship between Palaeoxonodon and Amphitherium. The position of the mandibular foramen, and the slight extension of the masseteric fossa into the body of the dentary are new autapomorphies for Palaeoxonodon.

Summary The production of meat from sheep and goats in Australia occurs almost entirely at pasture in zones known as the semi-arid pastoral zone, the wheat-sheep zone (where sheep and crops form an agricultural rotation system) and the high rainfall zone. Each zone has particular factors which affect the human health hazards associated with sheep and goat meat and the opportunities for prevention. The authors provide an overview of small ruminant production in Australia and a synopsis of the diseases encountered, including the factors which influence epidemiology. Animal health arrangements for underwriting food safety at the pre-harvest and post-harvest stages of production in Australia are also outlined. Specific public health hazards related to sheep and goat meat, together with measures for prevention, are considered under the headings of zoonoses, enteropathogens and chemical residues.

12 pages, 5 figures, 2 appendices.-- Full-text paper available Open Access at: http://ornithischia.googlepages.com/Barrettetal.-Hexinlusaurus.pdf, Three taxa of small-bodied ornithischian dinosaurs have been described from the Middle Jurassic (Lower Shaximiao Formation: ?Bajocian) locality of Dashanpu, Sichuan Province, People’s Republic of China. The taxonomy of these animals (Yandusaurus multidens, Xiaosaurus dashanpensis, and Agilisaurus louderbacki) has become highly confused, with many conflicting opinions regarding the validity of each species and the possible synonymies that might exist between them and other ornithischian taxa from both China and North America. Following re-examination of the relevant material, we propose that all three of the Dashanpu small ornithischians represent valid taxa, each of which can be diagnosed on the basis of at least one autapomorphy. In addition, these taxa can be distinguished from each other by a large number of cranial, dental, and postcranial character states. We demonstrate that ‘Yandusaurus’ multidens is not congeneric with either Y. hongheensis or any other taxon, and therefore propose the new generic name Hexinlusaurus for the reception of the species ‘Y.’ multidens. Consideration of the character states present in Hexinlusaurus, Agilisaurus, and Xiaosaurus shows that these taxa are not basal euornithopods (‘hypsilophodontids’), as had been suggested by the majority of previous authors, but represent more basal ornithischians. Hexinlusaurus and Agilisaurus can be regarded as Genasauria incertae sedis, whereas Xiaosaurus can only be recognized as Ornithischia incertae sedis on the basis of current data., For access to material in their care, and their excellent hospitality, PMB and RJB would like to thank Ouyang Hui and Peng Guangzhao (ZDM) and He Xin-Lu and Li Kui (GCC). Helpful reviews of an earlier draft of this paper were received from Xu Xing, D. B. Weishampel, and an anonymous referee. Travel to Zigong was supported by grants from the Royal Society of London (to PMB), The Jurassic Foundation (to PMB, RJB), the Cambridge Philosophical Society (to PMB), Emmanuel College, Cambridge (to RJB), and the Chancellerie des Universités de Paris (FK).