Abstract The cranial morphology of theropod dinosaurs has been used to examine the phylogeny, ontogeny, ecology and biomechanics of the clade. Previous studies have recognized that paedomorphosis and peramorphosis occurred multiple times throughout theropod evolution, with skull paedomorphism being one of the major changes during the transition from non-avialan theropods to birds. This study supplemented previous works with more detailed sampling of the morphological data of non-avialan paravians. Principal component analyses based on the cranial geometry confirm that the small-bodied non-avialan paravians have paedomorphic skulls compared with the early-diverging theropods, but independent peramorphosis is also observed in various groups. The secondary elongation of the preorbital portion of the cranium was present in both the late-diverging troodontids and the late-diverging dromaeosaurids, but it was achieved through different morphological configurations in these two lineages.

Abstract: Simple, three-dimensional, digital models of the crania and mandibles of 22 pterosaurs – 13 pterodactyloids and nine non-pterodactyloids (‘rhamphorhynchoids’) – were generated to investigate gross-level mechanical aspects of the skulls as they would related to feeding behaviour such as bite force and speed of jaw motions. The key parameter was the determination of second moments of area of the mid-muzzle region and the computation of the bending moment relative to the occiput. The shorter, stockier skulls of basal ‘rhamphorhynchoids’ were the strongest for their size in terms of potential resistance to dorso-ventral bending, and this finding correlates with their robust dentitions. More derived ‘rhamphorhynchoids’ showed the start of a trend towards weaker skulls, but faster jaw adduction was interpreted to be an adaptation for the snatching of small prey. Pterodactyloids continued the trend to lengthen the skull and to reduce its cross-sectional area, resulting in less stiff skulls, but more rapid opening and closing of the jaws. Changes in the rear of the skulls and the development of coronoid eminences on the mandibles of all the pterodactyloids are correlated with the reduction in bite force and a concomitant increase in jaw closing speed.

Abstract: The Solnhofen pterosaurs Pterodactylus antiquus , Aerodactylus scolopaciceps , Diopecephalus kochi , Germanodactylus cristatus and Germanodactylus rhamphastinus all have complicated taxonomic histories. Species originally placed in the genus Pterodactylus , such as Aerodactylus scolopaciceps , Ardeadactylus longicollum , Cycnorhamphus suevicus and Germanodactylus cristatus possess apomorphies not observed in the type species of Pterodactylus , and consequently have been placed in new genera. The affinities of another Solnhofen pterosaur previously placed in Pterodactylus , Diopecephalus kochi , are less clear. It has been proposed that D. kochi is a juvenile specimen of Pterodactylus antiquus , or perhaps ‘ Germanodactylus rhamphastinus ’ specimens are mature examples of D. kochi . Furthermore, studies have suggested that ‘ Germanodactylus rhamphastinus ’ is not congeneric with the type species of Germanodactylus. Geometric morphometric analysis of prepubes and a cladistic analysis of the Pterosauria elucidate plesiomorphic and apomorphic conditions for basal Jurassic pterodactyloids. Germanodactylus is found to be a monotypic genus and Pterodactylus , Diopecephalus , and ‘ G. rhamphastinus ’ are found as distinct taxa belonging in individual genera, diagnosable using a combination of characters. Thus, Diopecephalus kochi is not demonstrated to be congeneric with Germanodactylus or Pterodactylus and is maintained as a valid taxon. ‘ G. rhamphastinus ’ is readily distinguishable from other Solnhofen pterosaur taxa, and a new genus is erected for its reception. Supplementary material: Technical details of the mechanical theory behind this article are available at https://doi.org/10.6084/m9.figshare.c.3809401.v1

Abstract It has become accepted in recent years that the fossil record can preserve labile tissues. We report here the highly detailed mineralization of soft tissues associated with a naturally occurring brain endocast of an iguanodontian dinosaur found in c. 133 Ma fluvial sediments of the Wealden at Bexhill, Sussex, UK. Moulding of the braincase wall and the mineral replacement of the adjacent brain tissues by phosphates and carbonates allowed the direct examination of petrified brain tissues. Scanning electron microscopy (SEM) imaging and computed tomography (CT) scanning revealed preservation of the tough membranes (meninges) that enveloped and supported the brain proper. Collagen strands of the meningeal layers were preserved in collophane. The blood vessels, also preserved in collophane, were either lined by, or infilled with, microcrystalline siderite. The meninges were preserved in the hindbrain region and exhibit structural similarities with those of living archosaurs. Greater definition of the forebrain (cerebrum) than the hindbrain (cerebellar and medullary regions) is consistent with the anatomical and implied behavioural complexity previously described in iguanodontian-grade ornithopods. However, we caution that the observed proximity of probable cortical layers to the braincase walls probably resulted from the settling of brain tissues against the roof of the braincase after inversion of the skull during decay and burial. Supplementary material: Information regarding associated fossil material, and additional images, can be found at https://doi.org/10.6084/m9.figshare.c.3519984 Gold Open Access: This article is published under the terms of the CC-BY 3.0 license .

Abstract In 1884, Arthur Smith Woodward first met Charles Dawson, a solicitor and industrious amateur collector, antiquarian, geologist, archaeologist and palaeontologist. This began a long association and friendship centred on their mutual interest in palaeontology and human evolution. Dawson devised a complicated plot focused around the ancient river gravel deposits at Barkham Manor near the village of Piltdown, Sussex. In these gravels he planted stone tools and fossil mammal remains together with the lower jaw of an ape and numerous modern human cranial bones to deceive the scientific establishment into believing an early human ancestor had been found in his own back yard. Cleverly devised to provide anatomists and archaeologists with evidence for concepts that they wanted to believe were true, Dawson fuelled numerous contentious debates among scientists that quickly attracted international attention. Nothing could be more unfortunate than such a respectable scientist as Arthur Smith Woodward being taken in by the events of 1912, and then subsequently swept along by them well into his retirement right up to the time of his death in 1944.