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News Article | April 21, 2016
Site: www.rdmag.com

By analyzing data collected from 3,104 fossilized teeth from four different maniraptoran families (small bird-like dinosaurs), researchers from the University of Toronto, the Royal Tyrrell Museum of Palaeontology, and the Royal Ontario Museum believe that early modern birds thrived following the Cretaceous extinction due to their toothless beaks, which were perfect for seed consumption while other food sources dwindled. The study was recently published in Current Biology. The fossilized teeth spanned 18 million years, right up until the end-Cretaceous extinction. Across the four maniraptoran families, the teeth maintained their differences, leading the researchers to hypothesize that the ecosystem was rich and stable prior to the catastrophic extinction event. “There were bird-like dinosaurs with teeth up until the end of the Cretaceous, where they all died off very abruptly,” said study author Derek Larson, of the University of Toronto, in a statement. “Some groups of beaked birds may have been able to survive the extinction event because they were able to eat seeds.” According to the Smithsonian National Museum of Natural History, the extinction event, which many agree was helped along by an asteroid impact, was likely marked by global forest fires, and cold weather brought on by sun-blocking clouds and dust, which was followed by a period of hot climate due to a rise in carbon dioxide. “In the fallout of the bolide impact that marks the end of the Cretaceous, terrestrial food webs that relied on photosynthesis would have collapsed,” the researchers wrote. “However seed banks derived from plants, including relatively abundant angiosperms could have been a common, nutrient-rich resource that would have persisted among the detritus.” According to the researchers, a seed bank can remain viable for more than 50 years in modern temperate forests. Toothed maniraptorans were likely dependent on food chains that thrived on living plant matter, and were unable to indulge in seed banks. “Dietary specialization toward granivory in some lineages of crown group birds may have been one of the key factors in their survival through the end-Cretaceous mass extinction,” they wrote. Establish your company as a technology leader! For more than 50 years, the R&D 100 Awards have showcased new products of technological significance. You can join this exclusive community! Learn more.

News Article | October 28, 2016
Site: news.yahoo.com

SALT LAKE CITY — About 75 million years ago, a mosasaur — a dolphin-like, predatory, marine reptile that lived during the dinosaur age — bit another mosasaur so hard that it left its tooth behind, embedded in its foe's face, new research finds. Now, paleontologists are studying the remains of the victim, a creature that sustained not one, but two attacks on its face, likely from different adversaries, said paleontologist Takuya Konishi, an assistant professor at the University of Cincinnati. "The specimen represents the first direct, unequivocal evidence of nonlethal biting, and not predation, between mosasaurs," Konishi told Live Science, here at the 76th annual meeting of the Society of Vertebrate Paleontology. [T. Rex of the Seas: Images of Fierce Mosasaurs] A mining company discovered the 21-foot-long (6.5 meters) specimen in southern Alberta, Canada, in 2012, and promptly shared the news with the Royal Tyrrell Museum of Palaeontology. Museum researchers spent two years preparing the fossil, "during which [time] the specimen's unique scientific significance became clear: It had a tooth from another mosasaur embedded in its lower jaw," Konishi said. "We were all thrilled, and began working on it." The 74.8-million-year-old mosasaur was fully articulated, meaning that all of its bones were preserved in place. An analysis of the creature's anatomy, with the help of a computed tomography (CT) scan, suggests that it was a species in the Mosasaurusgenus, Konishi said. The remnants of the mosasaur attack — three lesions in all, including the still-embedded tooth — are visible on the left side of the mosasaur's face. All three lesions show signs of bone remodeling, indicating that the mosasaur survived the attack and began healing before the animal's demise, Konishi said. However, two genuses of mosasaurs lived in the region where the specimen was found, and it wasn't immediately clear which had bitten the victim. Mosasaurs in the genus Prognathodon had powerful teeth that could crunch through turtle shells, so it's unlikely that one of them would have broken a tooth while attacking another mosasaur, Konishi said. Rather, a mosasaur in the genus Mosasauruswas a likelier assailant, as these animals had long and pointy teeth that were more prone to breaking, Konishi said. The researchers found no evidence of any Mosasaurus bites on the other side of the victim's face, suggesting that the attacker came at its target at an angle from below, Konishi added. Perhaps competition for a mate sparked the Mosasaurus-on­-Mosasaurus fight, Konishi said. Mosasaurs are related to squamates, scaled reptiles such as snakes and lizards. Mosasaurs are extinct, but their distant relatives, squamates called gila monsters (Heloderma suspectum) are known to fight when competing for female mates, Konishi said. The male monsters will bite the underside of their opponents' throats as a way to prevent the other from biting back, Konishi said. "It is possible that a similar tactic was employed by the mosasaur individual that left its tooth in [the newfound specimen], where the bite was from one side of the jaw and from underneath — forceful enough to subdue the opponent but not to kill it," Konishi wrote in a preliminary draft of the study's abstract. A magnified look at the tooth left in the lower jaw of the mosasaur. Courtesy of the Royal Tyrrell Museum of Palaeontology The right side of the mosasaur's skull also showed bite marks, but there was less bone remodeling, indicating that the animal was bitten not long before it died, Konishi said. Moreover, these bite marks did not come from another Mosasaurus, and the assailant's identity is still unknown, Konishi said. This isn't the first time scientists have found evidence of mosasaurs going after their own kind. In 2013, researchers reported finding a fossilized mosasaur in Angola with the partial remains of three other mosasaur species in its gut. The new study has yet to be published in a peer-reviewed journal. In Images: The Tracks of an Ancient Sea Monster Rumor or Reality: The Creatures of Cryptozoology

Henderson D.M.,Royal Tyrrell Museum of Palaeontology
Journal of Vertebrate Paleontology | Year: 2010

Body masses for 14 species of pterosaur spanning four orders of magnitude were estimated using three-dimensional, digital models. The modeled taxa comprised seven paraphyletic 'rhamphorhynchoids': Anurognathus ammoni, Dimorphodon macronyx, Eudimorphodon ranzii, Jeholopterus ningchengensis, Preondactylus buffarinii, Rhamphorhynchus muensteri, and Sordes pilosus; and seven pterodactyloids: Anhanguera santanae, Dsungaripterus weii, Pteranodon longiceps, Pterodaustro guinazui, Pterodactylus sp., Quetzalcoatlus northropi, Tupuxuara longicristatus. The reliability of the mass estimation methods were tested with equivalent models of six extant species of bird with masses that spanned three orders of magnitude. The close agreement between model bird mass estimates and those of the living forms provides a level of confidence in the results obtained for the extinct pterosaurs. The masses of the axial body regions (tail, trunk, neck, head), limbs, and patagia of the pterosaurs were individually estimated and distinct differences in relative body proportions were found between species. Allometric relationships between body length and wingspan and body mass were derived for 'rhamphorhynchoids' and pterodactyloids to facilitate the estimation of body masses for other pterosaurs known from incomplete material, and these relationships also highlight differences in phyletic shape change between the two groups. The estimated mass for the largest pterosaur known, Quetzalcoatlus northropi, exceeds the previous highest estimates by more than 100%, and it is argued that this extremely large pterosaur is better interpreted as a secondarily flightless form. © 2010 by the Society of Vertebrate Paleontology.

Brown C.M.,Royal Tyrrell Museum of Palaeontology | Henderson D.M.,Royal Tyrrell Museum of Palaeontology
Current Biology | Year: 2015

Summary Ceratopsid (horned) dinosaurs are an iconic group of large-bodied, quadrupedal, herbivorous dinosaurs that evolved in the Late Cretaceous and were largely restricted to western North America [1-5]. Ceratopsids are easily recognized by their cranial ornamentation in the form of nasal and postorbital horns and frill (capped by epiossifications); these structures show high morphological disparity and also represent the largest cranial display structures known to have evolved [2, 4]. Despite their restricted occurrence in time and space, this group has one of the best fossil records within Dinosauria, showing a rapid diversification in horn and frill morphology [1]. Here a new genus and species of chasmosaurine ceratopsid is described based on a nearly complete and three-dimensionally preserved cranium recovered from the uppermost St. Mary River Formation (Maastrichtian) of southwestern Alberta. Regaliceratops peterhewsi gen. et sp. nov. exhibits many unique characters of the frill and is characterized by a large nasal horncore, small postorbital horncores, and massive parietal epiossifications. Cranial morphology, particularly the epiossifications, suggests close affinity with the late Campanian/early Maastrichian taxon Anchiceratops, as well as with the late Maastrichtian taxon Triceratops. A median epiparietal necessitates a reassessment of epiossification homology and results in a more resolved phylogeny. Most surprisingly, Regaliceratops exhibits a suite of cranial ornamentations that are superficially similar to Campanian centrosaurines, indicating both exploration of novel display morphospace in Chasmosaurinae, especially Maastrichtian forms, and convergent evolution in horn morphology with the recently extinct Centrosaurinae. This marks the first time that evolutionary convergence in horn-like display structures has been demonstrated between dinosaur clades, similar to those seen in fossil and extant mammals [6]. © 2015 Elsevier Ltd.

Henderson D.M.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2015

A very rare 11.2 m long wide-gauge trackway, made by an as yet undetermined large mammal, is described from the Lacombe Member (Late Paleocene) of the Paskapoo Formation (Paleocene). The exposure of the trackway was connected with the record-setting floods of 2013 in the province of Alberta as the tracks were exposed close to the base of the Brazeau Dam in west-central Alberta. The tracks are preserved on the top surface of a siltstone, but extensive erosion of the tracks resulted in the removal of details such as claw and digit traces, as well as any heel or palm impressions. The tracks are all circular to subcircular in outline, and it is not possible to determine the direction of travel of the trackmaker. Sequences of distinct pairings of adjacent tracks on both the left and right set of traces are present, and these are interpreted to represent manus-pes couples. The tracks do not show any overprinting. The mean pace angulations of the two best preserved sections range from 113° to 125°, while their mean stride lengths range from 95 to 96 cm. The lack of any distinctive anatomical details being preserved in the tracks prevents a precise identification of the trackmaker, but the sizes, shapes, and age of the tracks suggest that they could have been made by a large pantodont. © 2015, National Research Council of Canada. All Rights Reserved.

Eberth D.A.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2015

Upper Cretaceous dinosaur bonebeds are common in Alberta, Canada, and have attracted continuous scientific attention since the 1960s. Since its inception, the Royal Tyrrell Museum of Palaeontology has documented the presence of hundreds of these sites and has been involved directly in the scientific study of many tens. Because many of these bonebeds have been used to address questions about the paleobiology and paleoecology of dinosaurs, questions have arisen about bonebed origins and preservation in the Cretaceous of Alberta. This study of 260 bonebeds delineates broad paleoenvironmental settings and associations, and taphonomic signatures of assemblages as a first step in assessing patterns of dinosaur bonebed origins in the Upper Cretaceous of Alberta. Bonebeds are known predominantly from the Belly River Group and the Horseshoe Canyon, lower St. Mary River, Wapiti, and Scollard formations. In these units, bonebeds are mostly associated with river channel and alluvial wetland settings that were influenced by a subtropical to warm-temperate, monsoonal climate. Most bonebeds formed in response to flooding events capable of killing dinosaurs, reworking and modifying skeletal remains, and burying taphocoenoses. The “coastal-plain-flooding hypothesis,” proposed in 2005, suggested that many bonebeds in the Dinosaur Park Formation formed in response to the effects of recurring coastal-plain floods that submerged vast areas of ancient southern Alberta on a seasonal basis. It remains the best mechanism to explain how many of the bonebeds were formed and preserved at Dinosaur Provincial Park, and here, is proposed as the mechanism that best explains bonebed origins in other Upper Cretaceous formations across central and southern Alberta. © 2015, National Research Council of Canada. All Rights Reserved.

Braman D.R.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2015

The fossil pollen genus Morinoipollenites has been frequently reported in strata from the Upper Cretaceous of northern China and southeastern Russia. Pollen grains belonging to a single fossil species, Morinoipollenites normalis, have been only rarely encountered in Upper Cretaceous strata of North America. Just five specimens of Morinoipollenites have been recovered from sites of definite or probable Maastrichtian age in Alaska, Alberta, Saskatchewan, and Colorado. It is argued that the rarity in North America, common Asian occurrences, large size of pollen grains, and complex morphology of the pollen favour these pollen grains having been transported to North America from Asia by some vector. The transporting vector would most likely have been a flying organism based on the life styles of the producing plants and transporting organisms, long distance of transport, and morphology of the pollen grains. © 2015, National Research Council of Canada. All Rights Reserved.

Gardner J.D.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2015

The frog Tyrrellbatrachus brinkmani, gen. et sp. nov., is described on the basis of seven incomplete maxillae from vertebrate microfossil localities in the Upper Cretaceous (Campanian) Dinosaur Park Formation, in the Dinosaur Provincial Park area, southeastern Alberta, Canada. The maxillae are distinctive in a unique suite of features related to size, shape, and proportions of the bone, texture of the labial surface, form of the surface for inferred contact with the squamosal, form of the lamina horizontalis and the processus pterygoideus, relative depth of the crista dentalis, and in being edentulous (i.e., lacking teeth). The higher level affinities of Tyrrellbatrachus are uncertain, although certain features exclude it from several known families; for example, the presence of a processus pterygoideus excludes it from Gobiatidae (Late Cretaceous, Asia), whereas the presence of a crista dentalis and of a relatively unreduced pars facialis exclude it from Pipidae (Cretaceous–Recent, Africa and South America). The lack of teeth in Tyrrellbatrachus is notable because although tooth loss is widespread among extant anurans and has arisen independently multiple times, it has rarely been documented among Mesozoic anurans. Comparisons with the only other edentulous anuran from the Mesozoic of the Northern Hemisphere, namely Theatonius (late Campanian – late Maastrichtian, western USA), reveal no compelling similarities to support a close relationship between the two genera. Those taxa represent an early (Campanian) instance of independent tooth loss in anurans and, potentially, the oldest record of tooth loss in nonpipid anurans. © 2015, National Research Council of Canada. All Rights Reserved.

Neuman A.G.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2015

The Sulphur Mountain Formation in Alberta, Canada, comprises shales, siltstones, and limestones laid down on the continental shelf and shoreline along the western margin of the North American Craton during the Early and Middle Triassic. At least 13 taxa of fossil marine fishes have been found at a number of Triassic localities along the Front Ranges and foothills in Alberta. Common taxa (Boreosomus, Birgeria, Bobasatrania, Australosomus, Saurichthys, parasemionotids, and coelacanths) found at localities in Alberta are similar to those found at the classic Lower and Middle Triassic localities near Wapiti Lake, British Columbia, and in East Greenland, Spitzbergen, Madagascar, and China. The occurrence of Lower Triassic fishes in western Alberta shows that this fauna was widespread, occurring over at least 1000 km of shoreline, and that ecological and environmental factors were similar along the western edge of the Panthalassic Ocean during the Early Triassic. © 2015, National Research Council of Canada. All Rights Reserved.

Eberth D.A.,Royal Tyrrell Museum of Palaeontology | Braman D.R.,Royal Tyrrell Museum of Palaeontology
Canadian Journal of Earth Sciences | Year: 2012

The Upper Cretaceous paralic to nonmarine Horseshoe Canyon Formation (HCFm) of southern Alberta is divided into seven mappable members: Strathmore, Drumheller, Horsethief, Morrin, Tolman, Carbon, and Whitemud (bottom to top). This subdivision, based on combined outcrop and subsurface analyses, reflects lithostratigraphic variations related to changes in sea level (previously recognized) and newly documented changes in climate, volcanism, and orogenesis in an evolving foreland basin. Million-year-scale cycles of orogenesis resulted in changes in sediment supply and rates of subsidence in the basin and are interpreted in the context of a simple, two-phase foreland-basin sequence stratigraphic model: (i) overthrust loading resulting in reduced rates of sediment supply and subsidence in the most distal portions of the Alberta foredeep (our field area); (ii) tectonic quiescence leading to increased rates of sediment supply and subsidence during proximal-foredeep rebound. During the first ~2.5 Ma of its history (Strathmore and Drumheller members), the HCFm was tectonically and climatically "stable", and depositional style and stratigraphic architecture were influenced by vertical aggradation and modest progradation of shorelines. During the remaining ~4.5 Ma (Horsethief, Morrin, Tolman, Carbon, and Whitemud members), there were more complex and frequent changes in climate, volcanism, orogenesis, landscape weathering, and soil formation. Understanding this previously unrecognized complexity is critical for correctly assessing hydrocarbon resource distributions and biostratigraphic and taphonomic patterns.

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