A5085728528- Paleontology and Evolutionary Biology
- Evolution and Paleontology Studies
- Ichthyology and Marine Biology
- Amphibian and Reptile Biology
- Morphological variations and asymmetry
- Bat Biology and Ecology Studies
- Animal Behavior and Reproduction
- Neurobiology and Insect Physiology Research
- Fish biology, ecology, and behavior
- Physiological and biochemical adaptations
- Cephalopods and Marine Biology
- Ocular Infections and Treatments
- Plant and animal studies
- Astronomical Observations and Instrumentation
- Optical measurement and interference techniques
- Paleontology and Stratigraphy of Fossils
- Avian ecology and behavior
- Spider Taxonomy and Behavior Studies
- Pleistocene-Era Hominins and Archaeology
- Olfactory and Sensory Function Studies
- Parasite Biology and Host Interactions
- Birth, Development, and Health
- Dental Radiography and Imaging
- Radioactivity and Radon Measurements
- Geochemistry and Geologic Mapping
Johns Hopkins Medicine
2024
Johns Hopkins University
2024
Field Museum of Natural History
2021-2023
Planetary Science Institute
2021-2023
Yale University
2016-2023
American Museum of Natural History
2016-2023
Yale Peabody Museum
2020-2021
Whitney Museum of American Art
2018
University of Bristol
2014
University of Florence
2011-2013
We describe adaptations for a semiaquatic lifestyle in the dinosaur Spinosaurus aegyptiacus. These include retraction of fleshy nostrils to position near mid-region skull and an elongate neck trunk that shift center body mass anterior knee joint. Unlike terrestrial theropods, pelvic girdle is downsized, hindlimbs are short, all limb bones solid without open medullary cavity, buoyancy control water. The robust femur with hypertrophied flexor attachment low, flat-bottomed pedal claws...
Abstract Vertebrate hard tissues consist of mineral crystallites within a proteinaceous scaffold that normally degrades post-mortem. Here we show, however, decalcification Mesozoic preserved in oxidative settings releases brownish stained extracellular matrix, cells, blood vessels, and nerve projections. Raman Microspectroscopy shows these fossil soft are product diagenetic transformation to Advanced Glycoxidation Lipoxidation End Products, class N-heterocyclic polymers generated via...
The avian skull is distinctive in its construction and function. Much of bird anatomical variety expressed the beak; but beak itself, largely formed premaxillary bone, set upon a shortened face bulbous, enlarged braincase. Here, we use original observations reconstructions to describe overall form larger context provide general account evolutionary transformation from early dinosaur skull-the an archosaurian macropredator-to that modern birds. Facial shortening, enlargement braincase around...
Ouranosaurus nigeriensis is an iconic African dinosaur taxon that has been described on the basis of two nearly complete skeletons from Lower Cretaceous Gadoufaoua locality Ténéré desert in Niger. The entire holotype and a few bones attributed to paratype formed original description by Taquet (1976). A mounted skeleton appears correspond O. public display since 1975, exhibited at Natural History Museum Venice. It was never explicitly reported whether Venice specimen represents therefore,...
Abstract The most commonly preserved soft tissues associated with ornithischian dinosaurs are skin remains. apparent resistance of hadrosaur to decay, and its abundance in the fossil record relative that other tetrapods, has been attributed factors such as thickness composition. Here we report additional intrinsic within skin: 3D‐preserved eumelanin‐bearing bodies, dermal cells blood vessel fragments an organic matrix composed protein fossilization products. is much thinner than living...
Although evolvability of genes and traits may promote specialization during species diversification, how ecology subsequently restricts such variation remains unclear. Chemosensation requires animals to decipher a complex chemical background locate fitness-related resources, thus the underlying genomic architecture morphology must cope with constant exposure changing odorant landscape; detecting adaptation amidst extensive chemosensory diversity is an open challenge. In phyllostomid bats,...
Abstract Squamata is the most diverse clade of terrestrial vertebrates. Although origin pan-squamates lies in Triassic, oldest undisputed members extant clades known from nearly complete, uncrushed material come Cretaceous. Here, we describe three-dimensionally preserved partial skulls two new crown lizards Late Jurassic North America. Both species are placed at base skink, girdled, and night lizard Pan-Scincoidea, which consistently occupies a position deep inside squamate both...
Abstract Chemosensation is the most ubiquitous sense in animals, enacted by products of complex gene families that detect environmental chemical cues and larger-scale sensory structures process these cues. While there a general conception olfactory receptor (OR) genes evolve rapidly, universality this phenomenon across vertebrates, its magnitude, are unclear. The supposed correlation between molecular rates chemosensory evolution phenotypic diversity systems largely untested. We combine...
Sauropod dinosaurs include the largest terrestrial vertebrates that have ever lived. Virtually every part of sauropod body is heavily modified in association with gigantic size and associated physiological alterations. skulls are no exception: they feature elongated, telescoped facial regions connected to tilted neurocrania reoriented jaw adductor muscles. Several these cranial features been suggested be adaptations for feeding on one hand result paedomorphic transformation near base...
Evolutionary variation in ontogeny played a central role the origin of avian skull. However, its influence subsequent bird evolution is largely unexplored. We assess links between ontogenetic and evolutionary skull morphology Strisores (nightbirds). Nightbirds span an exceptional range ecologies, sizes, life-history traits craniofacial morphologies constituting ideal test for evo-devo hypotheses evolution. These include superficially ‘juvenile-like’ broad, flat skulls with short rostra large...
We report an isolated frontal of a large-bodied theropod from the Cenomanian "Kem Kem beds" Morocco with unusual morphology that we refer to new carcharodontosaurid distinct sympatric Carcharodontosaurus.The specimen shows unique combination plesiomorphic and potentially autapomorphic features: very thick broad bone complex saddle-shaped dorsal surface, narrow vertical lamina between prefrontal lacrimal facets.This study supports hypothesis fourth large was present in together...
Abstract During the latest Cretaceous, European Archipelago was characterized by highly fragmented landmasses hosting putative dwarfed, insular dinosaurs, claimed as fossil evidence of “island rule”. The Villaggio del Pescatore quarry (north-eastern Italy) stands most informative locality within palaeo-Mediterranean region and represents first, multi-individual Konservat-Lagerstätte type dinosaur-bearing in Italy. site is here critically re-evaluated early Campanian age, thus preceding final...
Eudromaeosauria is a clade of derived dromaeosaurids that typifies the common perception 'raptor' dinosaurs. The evolutionary history this has been controversial due to conflicting views taxonomic identity, and because, taphonomic bias, several species were diagnosed primarily or solely by maxilla. maxilla therefore crucial in understanding phylogenetic relationships within clade. Morphometric characterization commonly applied recognize distinguish major dromaeosaurid clades. However,...
Abstract Jeholornis is a representative of the earliest-diverging bird lineages, providing important evidence anatomical transitions involved in origins. Although ~100 specimens have been reported, its cranial morphology remains poorly documented owing to poor two-dimensional preservation, limiting our understanding and ecology key avian lineage Jeholornithiformes, addition evolution during origin early birds. Here, we provide detailed description osteology prima, based primarily on...
Ecology is a key driver of morphological evolution during adaptive radiations, but alternative factors like phylogeny and allometry can have strong influence on morphology. Lepidosaurs, the most diverse clade tetrapods, including lizards snakes, evolved remarkable variety forms adapted to disparate ecological niches, representing an ideal case study understand drivers evolution. Here, we quantify variation in lower jaw using three-dimensional geometric morphometrics broad sample 153...