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Exquisite discoveries and new interpretations regarding an enigmatic group of cursorial avemetatarsalians led to a new phylogenetic hypothesis regarding pterosaur affinities. Previously thought to be dinosaur precursors, lagerpetids are now considered to be the closest relatives to pterosaurs. This new hypothesis sheds light on a new explorable field, especially regarding the character acquisition and evolution within the pterosaur lineage. In the present study, the morphospace occupation of distinct skeletal regions of lagerpetids within the morphological spectrum of avemetatarsalians is investigated. This approach indicates which portions of the skeleton are more similar to the anatomy of pterosaurs and which portions present different homoplastic signals. The analyses demonstrate that the craniomandibular traits of lagerpetids are pterosaur-like, the pectoral girdle and forelimb are dinosauromorph-like and the axial skeleton and the pelvic girdle and hindlimb are unique and highly specialized among the analyzed sample. So, despite the close phylogenetic relationships, the postcranial skeleton of lagerpetids and pterosaurs are very different. The occurrence of two distinct and highly specialized groups of pterosauromorphs coexisting with a wide ecological range of dinosauromorphs during the Triassic suggests pressure for new niches occupation., (© 2022 American Association for Anatomy.)

The Istiodactylidae is a group of pterodactyloids characterised by large nasoantorbital fenestrae and labiolingually compressed teeth, with several records reported from the Early Cretaceous of northeastern China and western Europe. Here we report a new istiodactylid, Lingyuanopterus camposi gen. et sp. nov. from the Jiufotang Formation of Lingyuan, Liaoning, northeastern China. The holotype is represented by a near-complete skull, mandible and atlas-axis complex. It is distinguished from other istiodactylids by several characters, including two autapomorphies: short triangular tooth crowns with sharp mesial and distal carinae limited to the distal teeth, mandibular symphysis occupying approximately a quarter the mandible length. We also report the presence of helical jaw joints in istiodactylids, and provide a revised diagnosis of the clade Istiodactylidae, which includes five genera: Istiodactylus , Liaoxipterus , Nurhachius , Luchibang and Lingyuanopterus . Four pellets containing fish fragments were observed and are tentatively interpreted as bromalites of Lingyuanopterus . Although members of this clade possess similar skull morphologies, istiodactylids vary in terms of their dentition, with at least three forms from the Jiufotang Formation alone. This may represent different feeding strategies, and also indicate a similarity between the pterosaur assemblages of northeastern China and Britain during the Early Cretaceous., Competing Interests: The authors declare there are no competing interests., (©2022 Xu et al.)

Studies of soft tissue effects on joint mobility in extant animals can help to constrain hypotheses about joint mobility in extinct animals. However, joint mobility must be considered in three dimensions simultaneously, and applications of mobility data to extinct taxa require both a phylogenetically informed reconstruction of articular morphology and justifications for why specific structures' effects on mobility are inferred to be similar. We manipulated cadaveric hip joints of common quail and recorded biplanar fluoroscopic videos to measure a 'ligamentous' range of motion (ROM), which was then compared to an 'osteological' ROM on a ROM map. Nearly 95% of the joint poses predicted to be possible at the hip based on osteological manipulation were rendered impossible by ligamentous constraints. Because the hip joint capsule reliably includes a ventral ligamentous thickening in extant diapsids, the hip abduction of extinct ornithodirans with an offset femoral head and thin articular cartilage was probably similarly constrained by ligaments as that of birds. Consequently, in the absence of extraordinary evidence to the contrary, our analysis casts doubt on the 'batlike' hip pose traditionally inferred for pterosaurs and basal maniraptorans, and underscores that reconstructions of joint mobility based on manipulations of bones alone can be misleading., (© 2018 The Author(s).)

Pterosaurs were the first vertebrates to achieve active flight, with some derived forms reaching enormous size. Accumulating fossil evidence confirms earlier indications that selection for large size in these flying forms resulted in a light, yet strong skeleton characterized by fusion of many bones of the trunk. However, this process also added mechanical constraints on the mobility of the thorax of large pterosaurs that likely limited the options available for lung ventilation. We present an alternative hypothesis to recent suggestions of an avian-like mechanism of costosternal pumping as the primary means of aspiration. An analysis of the joints among the vertebrae, ribs, sternum, and pectoral girdle of large pterosaurs indicates limited mobility of the ribcage and sternum. Comparisons with modes of lung ventilation in extant amniotes suggests that the stiffened thorax, coupled with mobile gastralia and prepubic bones, may be most consistent with an extracostal mechanism for lung ventilation in large pterodactyloids, perhaps similar to a crocodile-like visceral displacement system., (© 2013 Wiley Periodicals, Inc.)

Adventure comics were one of the most popular forms of escapism for young people during the harsh period following the Spanish Civil War, until they were replaced by television in the 1960s. The heroes of these comic booklets faced all sorts of threats and monsters, often including dinosaurs, pterosaurs, and other animals from the past which proved ideal for personifying all the horrors that readers had to deal with on a daily basis, so they were destroyed in the cruellest way possible. As these were extinct and largely unknown creatures, the scriptwriters and artists had to use a considerable amount of imagination to fill in their many gaps. A sample of about five hundred pages of Spanish comic booklets featuring different reptiles of the past is analysed here to examine which species were favoured by readers, their role in these comics, and the general palaeontological ignorance that they often revealed. These results are also compared with similar studies of different geographical and temporal scope in order to assess similarities and differences. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that the invasive air sac system evolved at least three times independently in avemetatarsalians: in pterosaurs, sauropodomorphs and theropods. Data from sauropodomorphs showed that the pneumatic architecture in vertebrae first developed in camellate‐like trabeculae in the Triassic, later in camerate systems in Jurassic neosauropods, and finally camellate tissue in Cretaceous titanosaurs. This evolutionary trajectory has support from a considerable sampling of sauropodomorph taxa. However, the evolution of pneumatic bone tissues in Theropoda is less understood. We analyzed the computed tomography of Majungasaurus and Rahonavis, using densitometry rendering to differentiate the microarchitecture along the presacral axial skeleton of late Ceratosaurians and early Paravians. We also compared these results with scans of other theropod clades. Our analysis revealed an increase in pneumatic complexity in early paravians compared to the ceratosaurians. Majungasaurus presents some apneumatic neural spines, a condition also observed in Allosaurus. Majungasaurus also features some apneumatic centra despite the presence of lateral pneumatic fossae. This raises caution when evaluating PSP solely based on external morphology. We also found evidence of distinct patterns of PSP in maniraptorans. Considering that Majungasaurus, a late abelisaurid, inherited from their ceratosaurian ancestors, some apneumatic elements such as the neural spine and some centra, Rahonavis, an early paravian, took a different trajectory toward the full pneumatization of the axial skeleton. This characteristic provided paravians an advantage in gliding and flying. Also, unlike Sauropoda, pneumaticity in Theropoda apparently developed by increasing chamber volumes toward paravians. Similar studies on early Theropoda are needed to elucidate their condition and better describe the evolutionary trajectory of different groups. [ABSTRACT FROM AUTHOR]

Herein, we describe the first pterosaur material from the Lower Cretaceous of Victoria and the geologically oldest pterosaur material from Australia. The isolated material comprises a partial synsacrum and a left metacarpal IV from the lower Albian portion of the Eumeralla Formation at Dinosaur Cove, Cape Otway, Victoria. The vestiges of a supraneural plate in the synsacrum precludes assignment to the Azhdarchidae. Moreover, presence of a supraneural plate indicates that the synsacrum likely belongs to individual late in ontogeny, perhaps attaining osteological maturity. The synsacrum does not preserve any diagnostic features, and is regarded here as an indeterminate member of either the Archaeopterodactyloidea or Pteranodontia. Similarly, the metacarpal IV cannot be identified more precisely than Pterosauria indet. Positive identification of the fourth metacarpal is supported by the presence of a ginglymoid distal articular surface and proximodistal length. The metacarpal IV is distinct from others previously reported from Australia, in that it is substantially smaller; it is therefore interpreted to derive from a juvenile specimen. Despite the isolated nature of these remains, they extend the temporal and geographic range of pterosaurs in Australia, and in tandem with remains described elsewhere, indicate that the Pterosauria prevailed and potentially reproduced at high latitudes. [ABSTRACT FROM AUTHOR]

As the lowest horizon of the Early Cretaceous Jehol Biota, the Huajiying Formation of the northern Hebei Province, China is rich with avians and feathered dinosaurs, but lacks pterosaur record. Here the first pterosaur fossil is reported from the Huajiying Formation. The new pterosaur specimen is characterised by an unusual pedal configuration of a short and spread metatarsus with elongate digits, showing a close resemblance to the dentulous Ornithocheiroidea. The pedal configuration is diverse in pterosaurs, and is often associated with ecological adaptations. In contrast to the general pattern of the elongate metatarsus and short digits, the elongate digits of the dentulous ornithocheiroids (e.g., boreopterids and istiodactylids) might offset the shortened metatarsus to enlarge the pedal surface for paddling, representing a new strategy in adaptation to the aquatic environment. [ABSTRACT FROM AUTHOR]

The article reports that fossilized footprints of Dromaeosauriformipes rarus in South Korea suggest this sparrow-sized dinosaur flapped its feathered forelimbs while running, indicating a precursor to flight during the Cretaceous.

A recent study published in the Proceedings of the National Academy of Sciences suggests that a sparrow-size relative of Tyrannosaurus rex may have used its wings to run faster and lengthen its stride, potentially as a precursor to flight. Fossilized footprints from South Korea indicate that this microraptor dinosaur may have flapped its wings while running, providing new evidence that flight may have evolved multiple times in different dinosaur lineages. While some paleontologists remain skeptical of these claims, the study offers intriguing insights into the potential aerial behaviors of feathered dinosaurs. [Extracted from the article]

Studies of soft tissue effects on joint mobility in extant animals can help to constrain hypotheses about joint mobility in extinct animals. However, joint mobility must be considered in three dimensions simultaneously, and applications of mobility data to extinct taxa require both a phylogenetically informed reconstruction of articular morphology and justifications for why specific structures' effects on mobility are inferred to be similar. We manipulated cadaveric hip joints of common quail and recorded biplanar fluoroscopic videos to measure a 'ligamentous' range of motion (ROM), which was then compared to an 'osteological' ROM on a ROM map. Nearly 95% of the joint poses predicted to be possible at the hip based on osteological manipulation were rendered impossible by ligamentous constraints. Because the hip joint capsule reliably includes a ventral ligamentous thickening in extant diapsids, the hip abduction of extinct ornithodirans with an offset femoral head and thin articular cartilage was probably similarly constrained by ligaments as that of birds. Consequently, in the absence of extraordinary evidence to the contrary, our analysis casts doubt on the 'batlike' hip pose traditionally inferred for pterosaurs and basal maniraptorans, and underscores that reconstructions of joint mobility based on manipulations of bones alone can be misleading.

The origin of the air sac system present in birds has been an enigma for decades. Skeletal pneumaticity related to an air sac system is present in both derived non-avian dinosaurs and pterosaurs. But the question remained open whether this was a shared trait present in the common avemetatarsalian ancestor. We analyzed three taxa from the Late Triassic of South Brazil, which are some of the oldest representatives of this clade (233.23 ± 0.73 Ma), including two sauropodomorphs and one herrerasaurid. All three taxa present shallow lateral fossae in the centra of their presacral vertebrae. Foramina are present in many of the fossae but at diminutive sizes consistent with neurovascular rather than pneumatic origin. Micro-tomography reveals a chaotic architecture of dense apneumatic bone tissue in all three taxa. The early sauropodomorphs showed more complex vascularity, which possibly served as the framework for the future camerate and camellate pneumatic structures of more derived saurischians. Finally, the evidence of the absence of postcranial skeletal pneumaticity in the oldest dinosaurs contradicts the homology hypothesis for an invasive diverticula system and suggests that this trait evolved independently at least 3 times in pterosaurs, theropods, and sauropodomorphs. [ABSTRACT FROM AUTHOR]

Monospecific assemblages of non-avian theropod tracks are relatively rare in the Cretaceous of Korea, where assemblages dominated by the tracks of diverse tetrapods (birds, sauropods, ornithopods, and pterosaurs) are well known and widely distributed in the Haman and Jindong formations (Hayang Group). To date, few high-density assemblages of theropod tracks have been documented. A Haman Formation site on Adu Island reveals a small high-density assemblage of Grallator tracks (~29 tracks/m2). The tracks, which indicate registration on a sandy substrate infused with microbial mat, are indistinguishable from Grallator tracks known from a few other Lower Cretaceous sites in China and east Asia. Early and Middle Jurassic Grallator-dominated assemblages are common in east Asia, and persist into the Late Jurassic- Early Cretaceous (Neocomian) transition in China, where they are typically only associated with sauropodomorph tracks. Post-Neocomian (Aptian-Albian) Cretaceous assemblages from Korea are much more diverse, and characterised by tracks of sauropod and ornithopod dinosaurs, non-avian and avian theropods (birds), pterosaurs and other tetrapods. Post-Neocomian assemblages dominated by theropod tracks, are rare and no large monospecific grallatorid assemblages are currently known. [ABSTRACT FROM AUTHOR]

We report new ichnites corresponding to a trackway composed of three tetradactyl pedal footprints and plant remains near Southeastern Guatacondo, Tarapacá Region, within the transition of Majala and Chacarilla Formations (Late Jurassic-Early Cretaceous). The fossils were found in the context of a Copper Mining road construction at the PK23 site, Quebrada Blanca Phase 2 project, by the Teck Mining Company Quebrada Blanca S.A. We performed stratigraphical, paleobotanical, and paleoichnological studies, along with the footprint characterization and comparisons by Principal Component Analysis, and Discriminant Analysis of I-II, II-III and III-IV interdigital angles, using a large tetradactyl footprint morphological database of potential producers (dinosaurs, crocodiles, lepidosaurs, and pterosaurs). Additionally, we performed 3D pedal computer modeling kinematic analysis of the Chilesaurus diegosuarez i's 3D tetradactyl foot under two different sedimentary conditions (i.e. hard soil with superficial impression, and soft sediment with a penetrative impression), to test it as a potential trackmaker. The stratigraphic section reveals an association of siliciclastic facies, formed by the intercalation of fine-grained sandstones and wackes, with ripple marks, cross and horizontal lamination, evidencing intermittent moderate to low sedimentation energy. Among the plant material, several organs of the family Cheirolepidiaceae were identified such as, leaves and leafy branches of Brachyphyllum type, Classostrobus pollen cone, ovuliferous scales, and wood fragments related to Cupressinoxylon. The monodominance of Cheirolepidiaceae among the preserved macroflora allows inferring the characteristics of the environment in which the plants lived, highlighting halophytic, and temporarily arid conditions. Evidence as a whole, permits to interpret the depositional environment as an arid deltaic-littoral plain, temporarily covered with an ephemeral water layer associated with a stunted woody vegetation, in which terrestrial vertebrates walked by. Despite the low predictive power of the multivariate analysis, due to the various sources of morphological variability inherent to footprint formation, the PK23 footprints seem to better correspond to Dinosauria or Avialae as the most likely producers, rather than to Lepidosauria or Crocodylia, discarding the dinosaur Chilesaurus due to very low interdigital mediolateral rotation capabilities. • We studied a palaeobotanical and paleoichnological record exposed during the construction of a road leading to a copper mine. • Majala is the most likely bearing Formation. Its depositional environment is interpreted as an arid deltaic-littoral plain. • Different plant organs identified are all attributables to the Cheirolipidiaceae Family. • We performed multivaried analyses on an extensive tetradactyl footprint interdigital angle database. • We built a 3D kinematic model of Chilesaurus foot in order to compare it as a potential producer • PK23 footprintsbetter correspond to Dinosauria or Avialae as the most likely producer, but is distinct from Chilesauridae. [ABSTRACT FROM AUTHOR]

The article focuses on the retraction of six publications by former British Journal of Sports Medicine editor-in-chief Paul McCrory due to evidence of plagiarism and other issues, adding to previous retractions following similar concerns.

The latitudinal biodiversity gradient (LBG), the increase in biodiversity from the poles to the equator, is one of the most widely recognized global macroecological patterns, yet its deep time evolution and drivers remain uncertain. The Late Triassic (237–201 Ma), a critical interval for the early evolution and radiation of modern tetrapod groups (e.g. crocodylomorphs, dinosaurs, mammaliamorphs), offers a unique opportunity to explore the palaeolatitudinal patterns of tetrapod diversity since it is extensively sampled spatially when compared with other pre‐Cenozoic intervals, particularly at lower palaeolatitudes. Here, we explore palaeolatitudinal patterns of Late Triassic tetrapod diversity by applying sampling standardization to comprehensive occurrence data from the Paleobiology Database (PBDB). We then use palaeoclimatic model simulations to explore the palaeoclimatic ranges occupied by major tetrapod groups, allowing insight into the influence of palaeoclimate on the palaeolatitudinal distribution of these groups. Our results show that Late Triassic tetrapods generally do not conform to a modern‐type LBG; instead, sampling‐standardized species richness is highest at mid‐palaeolatitudes. In contrast, the richness of pseudosuchians (crocodylians and their relatives) is highest at the palaeoequator, a pattern that is retained throughout their subsequent evolutionary history. Pseudosuchians generally occupied a more restricted range of palaeoclimatic conditions than other tetrapod groups, a condition analogous to modern day reptilian ectotherms, while avemetatarsalians (the archosaur group containing dinosaurs and pterosaurs) exhibit comparatively wider ranges, which is more similar to modern endotherms, such as birds and mammals, suggesting important implications for the evolution of thermal physiology in dinosaurs. [ABSTRACT FROM AUTHOR]

The record of land tetrapods of the Cerro del Pueblo Formation (Late Cretaceous, Campanian), in Coahuila, includes turtles, pterosaurs, dinosaurs, and crocodyliforms. This last group is represented only by goniopholidids, indeterminate eusuchians, and Brachychampsa montana. In this work we report the first crocodyliform remains from La Parrita locality, Cerro del Pueblo Formation, based on one isolated tooth, vertebrae, and osteoderms. The association of crocodyliforms, turtles, dinosaurs, and charophyte oogonia provide evidence for stagnant to fluvial environments on a delta plain with tropical climate for the Cerro del Pueblo Formation during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

Azhdarchid pterosaurs have been known since 1972 from upper Campanian deposits of Alberta, Canada. Originally represented by only very fragmentary remains tentatively assigned to the genus Quetzalcoatlus, additional material uncovered over the years has revealed that the taxonomic identity of the Alberta pterosaur material is at odds with this in the light of the growing understanding of azhdarchid diversity. Here, we describe previously undocumented pterosaur remains from Alberta and reassess previously studied material. The specimens collected from the Dinosaur Park Formation can be assigned to a new genus and species Cryodrakon boreas, gen. et sp. nov. The largest elements referable to this taxon suggest that this genus reached sizes comparable to those of other giant azhdarchids. [ABSTRACT FROM AUTHOR]

The tongue, with fleshy, muscular, and bony components, is an innovation of the earliest land-dwelling vertebrates with key functions in both feeding and respiration. Here, we bring together evidence from preserved hyoid elements from dinosaurs and outgroup archosaurs, including pterosaurs, with enhanced contrast x-ray computed tomography data from extant taxa. Midline ossification is a key component of the origin of an avian hyoid. The elaboration of the avian tongue includes the evolution of multiple novel midline hyoid bones and a larynx suspended caudal to these midline elements. While variable in dentition and skull shape, most bird-line archosaurs show a simple hyoid structure. Bony, or well-mineralized, hyoid structures in dinosaurs show limited modification in response to dietary shifts and across significant changes in body-size. In Dinosauria, at least one such narrow, midline element is variably mineralized in some basal paravian theropods. Only in derived ornithischians, pterosaurs and birds is further significant hyoid elaboration recorded. Furthermore, only in the latter two taxa does the bony tongue structure include elongation of paired hyobranchial elements that have been associated in functional studies with hyolingual mobility. Pterosaurs and enantiornithine birds achieve similar elongation and inferred mobility via elongation of ceratobranchial elements while within ornithurine birds, including living Aves, ossified and separate paired epibranchial elements (caudal to the ceratobranchials) confer an increase in hyobranchial length. The mobile tongues seen in living birds may be present in other flighted archosaurs showing a similar elongation. Shifts from hypercarnivory to more diverse feeding ecologies and diets, with the evolution of novel locomotor strategies like flight, may explain the evolution of more complex tongue function. [ABSTRACT FROM AUTHOR]

The midline pattern of sternal ossification characteristic of the Cretaceous enantiornithine birds is unique among the Ornithodira, the group containing birds, nonavian dinosaurs and pterosaurs. This has been suggested to indicate that Enantiornithes is not the sister group of Ornithuromorpha, the clade that includes living birds and their close relatives, which would imply rampant convergence in many nonsternal features between enantiornithines and ornithuromorphs. However, detailed comparisons reveal greater similarity between neornithine (i.e. crown group bird) and enantiornithine modes of sternal ossification than previously recognized. Furthermore, a new subadult enantiornithine specimen demonstrates that sternal ossification followed a more typically ornithodiran pattern in basal members of the clade. This new specimen, referable to the Pengornithidae, indicates that the unique ossification pattern observed in other juvenile enantiornithines is derived within Enantiornithes. A similar but clearly distinct pattern appears to have evolved in parallel in the ornithuromorph lineage. The atypical mode of sternal ossification in some derived enantiornithines should be regarded as an autapomorphic condition rather than an indication that enantiornithines are not close relatives of ornithuromorphs. Based on what is known about molecular mechanisms for morphogenesis and the possible selective advantages, the parallel shifts to midline ossification that took place in derived enantiornithines and living neognathous birds appear to have been related to the development of a large ventral keel, which is only present in ornithuromorphs and enantiornithines. Midline ossification can serve to medially reinforce the sternum at a relatively early ontogenetic stage, which would have been especially beneficial during the protracted development of the superprecocial Cretaceous enantiornithines. [ABSTRACT FROM AUTHOR]

The Yangouxia dinosaur tracksites are well known for a diverse assemblage of tetrapod tracks preserved as natural impressions (concave epireliefs) on large bedding planes, representing a locally widespread surface marking the transition from a sand- to a mud-dominated sequence in the Hekou Group. Previous ichnological studies at these large sites have focused on the morphology and ichnotaxonomy of the tracks, including a single trackway representing the first pterosaur tracks reported from China. Here, we report a distinctly different assemblage associated with minor sandstones in the mud-dominated sequence 20 m above the main tracksite level. This assemblage consists of at least 20 pterosaur manus track casts attributed to a single ichnotaxon ( Pteraichnus). No pes tracks have been identified. These tracks mostly occur in random orientations, although one possible trackway segment is inferred, to represent walking progression. Manus-only pterosaur track assemblages are common and likely reflect differential registration depths of manus and pes and/or sub optimal preservation conditions. The tracks are associated with distinctive invertebrate traces including Cochlichnus, Spongeliomorpha and Paleophycus and suggest the pterosaurs were likely feeding on the invertebrate tracemakers. [ABSTRACT FROM AUTHOR]

Cretaceous tetrapod (dinosaur and pterosaur) tracks from Zhaojue County in Sichuan Province are locally very abundant. Large scale quarrying operations at the Sanbiluoga Copper Mine site have produced extensive exposures, and track material for detailed study. However, natural track-bearing outcrops also occur at a site in Jiefang Township. The traditions of the local Yi people, indigenous to the area, attribute such tracks to Zhigealu, a central creator hero-ancestor, who made the footprints while riding his heavenly steed through the area. Through seeing tracks exposed by quarrying the local people offered these legend-based interpretations, and reported the Jiefang site which was previously unknown to scientists from outside the area. Thus, it is important to pay attention to local legends about track makers since they may lead directly to significant fossil footprint discoveries. Thereby paleontology and ichnological research can benefit largely from archeological sciences as well as from oral narratives from the local people. The recently discovered sauropod trackway from Jiefang is an excellent example. It comprises 16 pes-manus sets arranged in a narrow-gauge pattern. A peculiarity is the combination of this feature with morphological characteristics known from typical wide-gaugeBrontopodustrackways suggesting a tentative assignment to cf.Brontopodus. The discovery enlarges the distribution and diversity ofBrontopodus-like trackways and their producers in the Cretaceous Sichuan Basin. [ABSTRACT FROM AUTHOR]

"We still need fossil evidence for feathers in the Triassic as well as unequivocal molecular evidence for the common origin between pterosaur pycnofibers and dinosaur feathers", Pêgas says. Now, a new study of a Brazilian fossil suggests that pterosaurs - leathery winged, flying reptiles only distantly related to dinosaurs - were also clad in tiny feathers of varying hues. [Extracted from the article]

Abstract: The first survey of vertebrate fossil tracks and trackways from the well-known Kem Kem beds of southern Morocco is here presented. The aims are to: (1) discuss the diversity of vertebrate trackmakers represented in two trace-yielding units at three localities, and (2) apply the novel data to ongoing debates about vertebrate ecological associations within the Kem Kem. The majority of the tracks we recorded from the Kem Kem are tridactyl theropod footprints; other dinosaurian track records include those of possible ornithopod dinosaurs, extremely rare as body fossils within Kem Kem collections. Traces of swimming turtles are reported, alongside the first tracks of crocodyliforms and possible pterosaurs to be recorded from the Moroccan Cretaceous (both unsurprising given their abundance as body fossil records in this region). Differences between the collected ichnological sample and faunal reconstructions made on the basis of skeletal evidence are discussed; as trace fossils record the same environment in which the trackmaker lived (i.e. not subject to post-mortem transportation), data of this type arguably provide a more precise palaeoecological sample than the heavily re-worked and usually fragmentary body fossils from the Kem Kem. [Copyright &y& Elsevier]

In the tails of dromaeosaurid dinosaurs and rhamphorhynchid pterosaurs, elongate osteological rods extend anteriorly from the chevrons and the prezygapophyses. These caudal rods are positioned in parallel and are stacked dorsoventrally. The fully articulated and three-dimensionally preserved caudal series of some dromaeosaurid specimens show that individually these caudal rods were flexible, not rigid as previously thought. However, examination of the arrangement of the caudal rods in cross-section indicates that the combined effect of multiple caudal rods did provide substantial rigidity in the dorsoventral, but not in the lateral, plane. The results of digital muscle reconstructions confirm that dromaeosaurids and rhamphorhynchids also shared greatly reduced caudofemoral muscles in the anterior tail region. The striking similarities between the tails of dromaeosaurids and rhamphorhynchids suggest that both evolved under similar behavioral and biomechanical pressures. Combined with recent discoveries of primitive deinonychosaurs that phylogenetically bracket the evolution of dromaeosaurid caudal rods between two arboreal gliding/flying forms, these results are evidence that the unique caudal morphologies of dromaeosaurids and rhamphorhynchids were both adaptations for an aerial lifestyle. [ABSTRACT FROM AUTHOR]

In the years since the first description of a pterosaur specimen in 1784, pterosaur research has inevitably advanced considerably. However the last decade has arguably seen a much greater increase in our knowledge than the preceding two centuries. Since the turn of the new millennium, more than 40 new pterosaur genera and species have been described and whole new clades have been discovered, in addition to much new data being developed on pterosaur anatomy, functional morphology, palaeobiology, systematics, ecology and more. We are perhaps at the start of a golden age of pterosaur research and much as the dinosaurs underwent a revolution in the 1970s through to the early 1990s, now the Pterosauria are taking their turn. There is also a new and wider interest in pterosaur work as it attracts both more researchers and greater public interest. Pterosaurs appear to be an increasingly popular aspect of paleontology in popular culture and of interest to the media, both mainstream and digital. [ABSTRACT FROM AUTHOR]

Northeastern China contains widely distributed Jurassic terrestrial strata that have yielded many spectacular mammal and pterosaur fossils, in addition to feathered dinosaur fossils and more recent discoveries from Jianchang, particularly from western Liaoning. However, the fossil-bearing stratigraphic succession, regional correlation, and age estimates of the fossils found in Jianchang County and nearby areas have been contentious. Here, we report on the vertebrate fossil-bearing Jurassic stratigraphy from Linglongta, Jianchang County, western Liaoning, including a SHRIMP U-Pb zircon date unambiguously associated with the fossil horizons. The primary goal was to determine the vertebrate fossil-bearing succession. A further aim was to provide age estimations for the fossil-bearing horizon as well as the earliest appearance of feathered dinosaurs, the eutherian-placental clade, and transitional pterosaurs. Field investigations showed that the vertebrate fossil-bearing stratigraphic succession in Jianchang County mainly consists of basal andesites overlain by rhythmic tuffs and tuffaceous lacustrine sediments, with the upper intermediate or acidic lavas interbedded with laminated more or less tuffaceous lacustrine deposits. This sequence correlates well with the Middle Jurassic Lanqi/Tiaojishan Formation in northeastern China. Detailed and accurate field observations showed that the well-preserved vertebrate fossils were buried in either the middle or the upper fine-grained laminated lacustrine deposits. Previous and current SHRIMP U-Pb zircon dates provide an age estimation of 161-159 Myr for the fossil-bearing horizon and vertebrates. This indicates that the earliest appearance of feathered dinosaurs here was more than 159 Myr ago and unquestionably older than Archaeopteryx from Germany, making these the earliest known feathered dinosaurs in the world. Furthermore, the eutherian-placental clade and the known transitional pterosaurs first emerged no later than 161 Myr. The vertebrate assemblage unearthed recently from Linglongta and neighboring areas in Jianchang County belongs to the Daohugou Biota. In addition to feathered dinosaurs, this biota was characterized by mammals, primitive pterosaurs, insects, and plants and was present in Inner Mongolia, western Liaoning, and northern Hebei in northeastern China during the Middle-Late Jurassic. [ABSTRACT FROM AUTHOR]

Abstract: Stomach contents preserved in fossil specimens provide direct evidence for the diet of extinct animals. Such exceptional fossils remain rare for predatory non-avian dinosaurs and each can add significantly to our understanding of trophic interactions between various taxa. Here we present evidence for the dromaeosaurid theropod Velociraptor scavenging on the carcass of an azhdarchid pterosaur, with a long bone of the pterosaur being found as gut contents of the dinosaur. Despite previous inferences of dromaeosaurs as hyper-predators, scavenging appears to have been an important part of their ecology. [Copyright &y& Elsevier]

Hone, D.W.E., Naish, D. & Cuthill, I.C. 2011: Does mutual sexual selection explain the evolution of head crests in pterosaurs and dinosaurs? Lethaia, Vol. 45, pp. 139-156. Cranial ornamentation is widespread throughout the extinct non-avialian Ornithodira, being present throughout Pterosauria, Ornithischia and Saurischia. Ornaments take many forms, and can be composed of at least a dozen different skull bones, indicating multiple origins. Many of these crests serve no clear survival function and it has been suggested that their primary use was for species recognition or sexual display. The distribution within Ornithodira and the form and position of these crests suggest sexual selection as a key factor, although the role of the latter has often been rejected on the grounds of an apparent lack of sexual dimorphism in many species. Surprisingly, the phenomenon of mutual sexual selection - where both males and females are ornamented and both select mates - has been ignored in research on fossil ornithodirans, despite a rich history of research and frequent expression in modern birds. Here, we review the available evidence for the functions of ornithodiran cranial crests and conclude that mutual sexual selection presents a valid hypothesis for their presence and distribution. The integration of mutual sexual selection into future studies is critical to our understanding of ornithodiran ecology, evolution and particularly questions regarding sexual dimorphism. □ Behaviour, Dinosauria, ornaments, Pterosauria, sexual selection. [ABSTRACT FROM AUTHOR]

Abstract: The Early Cretaceous Jehol Biota in China has produced numerous well preserved fossils of feathered theropods and early birds. Recent discoveries of feathered dinosaurs, as well as transitional pterosaurs and a sexually mature individual of Darwinopterus preserved together with an egg from the Daohugou Biota of an earlier age than the Jehol Biota, in northeastern China, have greatly enriched our knowledge of the transition from dinosaurs to birds and primitive to derived pterosaurs. The age estimate of fossils or host strata, however, has proven to be contentious and varies widely from the Middle Jurassic to the Early Cretaceous. Here, we report a SHRIMP U–Pb zircon date unambiguously associated with the fossil horizons, and thus, for the first time, provide an age calibration for the earliest appearance of feathered dinosaurs and transitional pterosaurs. Date results indicate that the feathered dinosaurs of China were present more than 161Ma ago, unquestionably older than Archaeopteryx in Germany, and are the earliest known feathered dinosaurs in the world. Furthermore, feathers appeared in ornithischians before 159Ma rather than late in the Early Cretaceous. The known transitional pterosaurs first emerged before 161Ma. The Daohugou Biota, containing mammals, primitive pterosaurs, insects and plants, in addition to the feathered dinosaurs, was living in Inner Mongolia ,western Liaoning and northern Hebei in northeastern China during the Middle Jurassic. [Copyright &y& Elsevier]

Modern crocodilians and birds are the only living representatives of the Archosauria, a group that also includes non-avian dinosaurs and pterosaurs. Modern crocodilians originated during the early Cretaceous period and dispersed globally. Examples of physiological similarities between living crocodilians and birds include similar amino acids in β-keratins among crocodiles, turtles and birds; oviduct homologies between crocodilians and birds; similar forelimb structures in crocodiles and other archosaurs and similarities in gene expression in limb development in alligators and chickens. While individual crocodilian species have adapted their behaviours to meet specific strategies for survival in specific habitats, core reproductive behaviours are universal among modern crocodilians and transcend speciation, morphology and geographic distribution. Hard-wired core behaviours include social signals that incorporate chemosensory, auditory and mechanoreception modalities; construction of a temperature-stabilising nest chamber to incubate eggs; and parental care of their young. Parental care may reflect a primitive character for archosaurs, including dinosaurs. Crocodilians use integumentary sense organs (ISOs) during courtship and in parental care, and similar structures may have had similar functions in dinosaurs. The presence of numerous foramina (possible ISOs) in the skulls of saurischians, along with the findings of fossilised nests with adults, may indicate similar complex behaviours, including parental care, in dinosaurs. [ABSTRACT FROM AUTHOR]

The early evolutionary history of Ornithodira (avian-line archosaurs) has hitherto been documented by incomplete (Lagerpeton) or unusually specialized forms (pterosaurs and Silesaurus). Recently, a variety of Silesaurus-like taxa have been reported from the Triassic period of both Gondwana and Laurasia, but their relationships to each other and to dinosaurs remain a subject of debate. Here we report on a new avian-line archosaur from the early Middle Triassic (Anisian) of Tanzania. Phylogenetic analysis places Asilisaurus kongwe gen. et sp. nov. as an avian-line archosaur and a member of the Silesauridae, which is here considered the sister taxon to Dinosauria. Silesaurids were diverse and had a wide distribution by the Late Triassic, with a novel ornithodiran bauplan including leaf-shaped teeth, a beak-like lower jaw, long, gracile limbs, and a quadrupedal stance. Our analysis suggests that the dentition and diet of silesaurids, ornithischians and sauropodomorphs evolved independently from a plesiomorphic carnivorous form. As the oldest avian-line archosaur, Asilisaurus demonstrates the antiquity of both Ornithodira and the dinosaurian lineage. The initial diversification of Archosauria, previously documented by crocodilian-line archosaurs in the Anisian, can now be shown to include a contemporaneous avian-line radiation. The unparalleled taxonomic diversity of the Manda archosaur assemblage indicates that archosaur diversification was well underway by the Middle Triassic or earlier. [ABSTRACT FROM AUTHOR]

Azhdarchid pterosaurs were among the most widespread and successful of pterosaur clades, but their paleoecology remains controversial. Morphological features common to all azhdarchids include a long, shallow rostrum; elongate, cylindrical cervical vertebrae that formed a long and unusually inflexible neck; and proportionally short wings with an abbreviated fourth phalanx. While azhdarchids have been imagined as vulture-like scavengers, sediment probers, swimmers, waders, aerial predators, or stork-like generalists, most recent authors have regarded them as skim-feeders, trawling their lower jaws through water during flight and seizing aquatic prey from the water's surface. Although apparently widely accepted, the skim-feeding model lacks critical support from anatomy and functional morphology. Azhdarchids lack the many cranial specialisations exhibited by extant skim-feeding birds, most notably the laterally compressed lower jaw and shock absorbing apparatus required for this feeding style. Well-preserved azhdarchid skulls are rare, but their rostra and lower jaws appear to have been sub-triangular in cross-section, and thus dissimilar to those of skim-feeders and sediment probers. Taphonomic data indicates that azhdarchids predominately inhabited inland settings, and azhdarchid morphology indicates that they were poorly suited for all proposed lifestyles bar wading and terrestrial foraging. However, azhdarchid footprints show that their feet were relatively small, padded and slender, and thus not well suited for wading. We argue that azhdarchids were stork- or ground hornbill-like generalists, foraging in diverse environments for small animals and carrion. Proficient terrestrial abilities and a relatively inflexible neck are in agreement with this interpretation. [ABSTRACT FROM AUTHOR]

Pterosaurs, the flying reptiles of the Mesozoic, often play second fiddle in popularity to their contemporaries, the dinosaurs. Such treatment conceals the remarkable diversity and biology of this group: not only were pterosaurs the first vertebrates to achieve powered flight, but they also existed for 160 million years—longer than any other flying vertebrates. Named after the Uzbek mythical dragon ‘azhdarkho’, the Azhdarchidae are among the most enigmatic of all pterosaurs. As with most pterosaurs, azhdarchid remains are rare, and their fossil record is largely represented by isolated bones or incomplete skeletons. Despite the collection of azhdarchid fossils over the last 100 years, recognition of these pterosaurs as a distinct group was not achieved until relatively recently. It is now clear that the azhdarchids were a highly successful group that probably first appeared in the Early Cretaceous, gradually spreading across the globe until the latest Cretaceous when they, as one of the last remaining groups of pterosaurs, became extinct. Although most notable for achieving wingspans comparable with light aircraft, other aspects of azhdarchid morphology and ecology make them not just aberrant animals but also unusual pterosaurs. [ABSTRACT FROM AUTHOR]

Abstract: Diverse and well-preserved assemblages of dinosaur (theropod, sauropod and ornithopod), pterosaur, and bird tracks from the Hekou Formation (Lower Cretaceous) in the Yellow River (Huang He) valley represent the first significant fossil footprint discoveries in Gansu Province, China. However, the sites are large, visually spectacular, and well-exposed thanks to labor-intensive hand excavation. The sites have the potential for development as educational and tourist destinations. These sites have become one of the National Geoparks in China. Dinosaur tracks include at least two theropod morphotypes that range in size from about 5 to >30cm in length. Wide-gauge sauropod tracks (Brontopodus) range in size from 25 to 90cm (pes length) and are the best-preserved examples known from China, with clear claw impressions. One trackway suggests an accelerating/running individual. Parallel ornithopod trackways indicate gregarious behavior. An enigmatic trackway may be a manus-only ornithopod trackway. A pterosaur trackway (cf. Pteraichnus), the first reported from China, consists of 24 consecutive footprints, and is the longest, well-preserved trackway on record. Bird tracks (cf. Aquatilavipes) are also very well preserved. The tracks occur at multiple stratigraphic levels in fluvio-lacustrine sequences of paleosol mudstones and sandstones with mud cracks and wave ripple marks. A minimum ichnodiversity of eight, the highest reported from the Cretaceous of China, is estimated. The saurischian component (theropods and sauropods) compares well with Inner Mongolia ichnofaunas from the Jing Chuan Formation. However, the co-occurrence of ornithopod and sauropod tracks is rare in Asia and globally, and compares with assemblages from South Korea, a similar Cretaceous paleolatitude (ca. 30°). [Copyright &y& Elsevier]

It is a basis of darwinian evolution that the microevolutionary mechanisms that can be studied in the present are sufficient to account for macroevolution. However, this idea needs to be tested explicitly, as highlighted here by the example of the superceding of dinosaurs and pterosaurs by birds and placental mammals that occurred near the Cretaceous/Tertiary boundary ∼65 million years ago. A major problem for testing the sufficiency of microevolutionary processes is that independent ideas (such as the existence of an extraterrestrial impact, and the extinction of dinosaurs) were linked without the evidence for each idea being evaluated separately. Here, we suggest and discuss five testable models for the times and divergences of modern mammals and birds. Determination of the model that best represents these events will enable the role of microevolutionary mechanisms to be evaluated. The question of the sufficiency of microevolutionary processes for macroevolution is solvable, and available evidence supports an important role for biological processes in the initial decline of dinosaurs and pterosaurs. [Copyright &y& Elsevier]

In this article we describe in a new and exceptionally well-preserved pterodactyloid pterosaur, Sinopterus dongi gen. et sp. nov. from the Jiufotang Formation in western Lianoning Province of northeast Chain. The new species is referred to the family Tapejaridae, representing its first record outside Brazial. It also represents the earliest occurrence as well as the most complete skeleton of the family. Some revisions are made about the family according to the morphological observations of the postcranial bones of Sinopteras. Two pterosaur assemblages appear to have existed in the Jehol Group, represented by the lower Yixian Formation and upper Jiufotang Formation, respectively. The lower pterosaur assemblage shows some resemblance to that of the Late Jurassic in Solnhofen (Tithonian) by sharing members of the Pterodactylidae and Anurognathidae. The upper one shows more resemblance to that of the Early Cretaceous Santana Formation (Aptian/Albian) by comprising only pterodactyloids such as the Tapejaridae. The age of the Yixian Formation is younger than that of the Solnhofen lithographic limestone, and the age of the Jiufotang Formation (Aptian) is slightly older than the Santana Formation.

Our understanding of the pterosaurs' place within the reptilian lineage has had a long and complex history. The unusual morphology of pterosaurs, which is inextricably linked to their habit of powered flight, has generated numerous proposals over the years regarding their exact origin and systematic position. Though it was concluded early on in pterosaur research history that these animals represented a group of derived flying reptiles, their exact origination remained mysterious for a long time and is still somewhat controversial. A rough consensus has now been reached that pterosaurs are derived archosaurs and are likely close relatives of the dinosaurs, united with them in the clade Ornithodira, though some still challenge this view. The anatomical evidence in support of this position close to Dinosauria is also admittedly fairly limited at present, largely owing to a lack of any clear-cut transitional 'proto-pterosaur' taxa (albeit that some fragmentary specimens have been suggested to represent exactly this). Differing hypotheses have also recently been put forward as to the exact interrelationships between the pterosaurs and other non-dinosaurian and dinosaurian ornithodirans. Here the previous hypotheses of where pterosaurs fit into the reptilian lineage and the anatomical evidence in support of the current hypotheses are reviewed. Results of new analyses are included that looked to test the origin and systematic position of the Pterosauria using an expanded version of a large anatomical dataset of archosaurs, within which several previously unconsidered early pterosaur taxa and a suit of new anatomical characters were considered. The analyses in this study support the close affinities between pterosaurs and dinosauriforms within Ornithodira; Pterosauria is recovered as the sister-taxon to Lagerpetidae. Such a result suggests that the clade Pterosauria belongs with Lagerpetidae as part of a broader Pterosauromorpha that then, with Dinosauriformes, falls within Ornithodira. The anatomical evidence in support of this position within Ornithodira is also discussed in detail. [ABSTRACT FROM AUTHOR]

The article reviews exhibitions for 2014 - 2015 including "Pterosaurs: Flight in the Age of Dinosaurs" in New York from April 5 - January 5, "The Valley of Astonishment" in London from June 20 - July 12, and "Britain: One Million Years of the Human Story" in London from February 13 - September 28.