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Beyond clinical areas, photon-counting detector (PCD) CT is innovatively applied to study paleontological specimens. This study presents a preliminary investigation into the application of PCD-CT for imaging large dinosaur fossils, comparing it with standard energy-integrating detector (EID) CT. The left dentary of Tyrannosaurus and the skull of Camarasaurus were imaged using PCD-CT in ultra-high-resolution mode and EID-CT. The PCD-CT and EID-CT image quality of the dinosaurs were visually assessed. Compared with EID-CT, PCD-CT yielded higher-resolution anatomical images free of image deterioration, achieving a better definition of the Tyrannosaurus mandibular canal and the three semicircular canals of Camarasaurus. PCD-CT clearly depicts the internal structure and morphology of large dinosaur fossils without damaging them and also provides spectral information, thus allowing researchers to gain insights into fossil mineral composition and the preservation state in the future.

Two new insect-related ichnogenera are reported in fossil dinosaur bones from Upper Cretaceous continental strata in Madagascar and Utah. Cubiculum ornatus n. igen. and isp. is described from numerous fossil bones in the Upper Cretaceous Maevarano Formation of northwestern Madagascar, and consists of hollow, ovoid chambers with concave flanks excavated into both spongy and compact bone. Traces similar in morphology to Cubiculum ornatus have been reported elsewhere in North America, Asia, Europe, and Africa in bones ranging in age from Jurassic to Pleistocene, and have been interpreted as pupal chambers constructed by carrion beetle larvae. Osteocallis mandibulus n. igen. and isp. is described in dinosaur bones from continental deposits of the Upper Cretaceous Maevarano Formation of Madagascar and the Upper Cretaceous Kaiparowits Formation of southern Utah. O. mandibulus consists of shallow, meandering surface trails, composed of numerous arcuate grooves, bored into compact (cortical) bone surfaces, and is tentatively interpreted as a feeding trace. Based on similar patterns of bioglyph preserved in both Cubiculum ornatus and Osteocallis mandibulus, the tracemaker is interpreted to be the same or similar for both borings. Given the recurrent association with animal remains, the tracemaker is furthermore presumed to be a necrophagous or osteophagous insect that used bone as a substrate for both reproduction (C. ornatus) and feeding (O. mandibulus).

During the Early Cretaceous, lakes, meandering streams, and flood plains covered the region where the current foothills of Rioja now exist. Today the area is known for its wine and for the dozens of sites where footprints and trackways of dinosaurs, amphibians, and even pterosaurs can be seen. The dinosaurs that lived here 120 million years ago left their footsteps imprinted in the mud and moist soil. Now fossilized in rock, they have turned Rioja into one of the most valuable dinosaur footprint sites in all of Europe. Félix Pérez-Lorente and his colleagues have published extensively on the region, mostly in Spanish-language journals. In this volume, Pérez-Lorente provides an up-to-date synthesis of that research in English. He offers detailed descriptions of the sites, footprints, and trackways, and explains what these prints and tracks can tell us about the animals who made them.

A large dinosaur bone bed has been investigated in the Udurchukan Formation (?late Maastrichtian) at Blagoveschensk, Far Eastern Russia. The observed mixture of unstratified fine and coarse sediments in the bone bed is typical for sediment-gravity-flow deposits. It is postulated that sediment gravity flows, originating from the uplifted areas at the borders of the Zeya-Bureya Basin, reworked the dinosaur bones and teeth as a monodominant bone bed. Fossils of the lambeosaurine Amurosaurus riabinini form >90% of the recovered material. The low number of associated skeletal elements at Blagoveschensk indicates that the carcasses were disarticulated well before reworking. Although shed theropod teeth have been found in the bone bed, <2% of the bones exhibit potential tooth marks; scavenging activity was therefore limited, or scavengers had an abundance of prey at hand and did not have to actively seek out bones for nutrients. Perthotaxic features are very rare on the bones, implying that they were not exposed subaerially for any significant length of time before reworking and burial. The underrepresentation of light skeletal elements, the dislocation of the dental batteries, and the numerous fractured long bones suggest that most of the fossils were reworked. The random orientation of the elements might indicate a sudden end to transport before stability could be reached. The size-frequency distributions of the femur, tibia, humerus, and dentary elements reveal an overrepresentation of late juveniles and small subadult specimens, indicative of an attritional death profile for the Amurosaurus fossil assemblage. It is tentatively postulated that the absence of fossils attributable to nestling or early juvenile individuals indicates that younger animals were segregated from adults and could join the herd only when they reached half of the adult size.

The Jurassic and Cretaceous are considered to have been warmer than today on the basis of various climate data and model studies. Here, we use the available global record of climate‐sensitive sediments, plants, and dinosaurs to infer broadscale geographic patterns for the Late Jurassic. These provide a context for our more detailed accounts of the Morrison and Tendaguru Formations in North America and East Africa. At the global scale, evaporites predominated in low latitudes and coals in mid‐ to high latitudes. We ascribe these variations to a transition from drier to wetter conditions between the equator and poles. Plant diversity was lowest in equatorial regions, increasing to a maximum in midlatitudes and then decreasing toward the poles. Most dinosaur remains are known from low‐latitude to marginally midlatitude regions where plant fossils are generally sparse and evaporites common. Conversely, few dinosaur remains are known from mid‐ to high latitudes, which have higher floral diversities and abundant coals. Hence, there is an obvious geographic mismatch between known dinosaur distributions and their primary food source. This may be due to taphonomic bias, indicating that most dinosaur discoveries provide only a small window on the diversity and lifestyles of this group. On the basis of our global‐ and local‐scale studies, we suggest that dinosaur preservation was favored in environments toward the drier end of the climate spectrum, where savannas rather than forests predominated. A holistic approach, incorporating climate and vegetation as well as geography, is required to better understand patterns of dinosaur ecology and evolution.

The extent of racemization of aspartic acid, alanine, and leucine provides criteria for assessing whether ancient tissue samples contain endogenous DNA. In samples in which the D/L ratio of aspartic acid exceeds 0.08, ancient DNA sequences could not be retrieved. Paleontological finds from which DNA sequences purportedly millions of years old have been reported show extensive racemization, and the amino acids present are mainly contaminates. An exception is the amino acids in some insects preserved in amber.

The association of vertebrate, invertebrate, plant, and ichnofossils from two Upper Cretaceous lacustrine environments in West Texas permits interpretation of the paleolimnology of part of the Javelina Formation. The relatively rich fossil assemblages permit studies of paleoenvironments and food web complexities, as well as provide paleohydrological information. In Big Bend National Park, at least three juvenile Alamosaurus sauropods were preserved in situ in anoxic mud among shallow-water lacustrine charophytes. Alamosaur remains in the Moon Valley section are both in situ and transported. Mussels, gastropods, gar, and crayfish trace fossils largely define the paleoecology, as well as reveal details of specific biological relationships, especially at several intervals in Moon Valley. The modern larval-host reproduction system of mussels may have existed in the possible case of an ectoparasitic relationship in the co-occurrence of fossil Unio and Lepisosteus. Relatively fine time-frame resolution is present based on investigations of the mussel, Unio, and the presence of crayfish burrows. Unio sclerochronology indicates continuous inundation for at least seven years at two different stratigraphic intervals. Horizons of fossil crayfish burrows record both periods of nondeposition and the level of the water table at those times. Viviparus gastropods suggest subtleties of water movement and oxygen concentration. Studies of the dinosaur bones and the presence of probable footprint impressions suggest dinosaurs visited these types of water bodies.