News Article | September 2, 2016
A rare small-bodied pterosaur, a flying reptile from the Late Cretaceous period approximately 77 million years ago, is the first of its kind to have been discovered on the west coast of North America. Pterosaurs are the earliest vertebrates known to have evolved powered flight. The specimen is unusual as most pterosaurs from the Late Cretaceous were much larger with wingspans between 4 and 11 meters (the biggest being as large as a giraffe, with a wingspan of a small plane), whereas this new specimen had a wingspan of only 1.5 meters. The fossils of this animal are the first associated remains of a small pterosaur from this time, comprising a humerus, dorsal vertebrae (including three fused notarial vertebrae) and other fragments. They are the first to be positively identified from British Columbia, Canada and have been identified as belonging to an azhdarchoid pterosaur, a group of short-winged and toothless flying reptiles which dominated the final phase of pterosaur evolution. Previous studies suggest that the Late Cretaceous skies were only occupied by much larger pterosaur species and birds, but this new finding, which is reported in the Royal Society Open Science journal, provides crucial information about the diversity and success of Late Cretaceous pterosaurs. "This new pterosaur is exciting because it suggests that small pterosaurs were present all the way until the end of the Cretaceous, and weren't outcompeted by birds. The hollow bones of pterosaurs are notoriously poorly preserved, and larger animals seem to be preferentially preserved in similarly aged Late Cretaceous ecosystems of North America. This suggests that a small pterosaur would very rarely be preserved, but not necessarily that they didn't exist," said lead author Elizabeth Martin-Silverstone, a palaeobiology PhD Student at the University of Southampton. The fossil fragments were found on Hornby Island in British Columbia in 2009 by a collector and volunteer from the Royal British Columbia Museum, who then donated them to the Museum. At the time, it was given to Victoria Arbour, a then PhD student and dinosaur expert at the University of Alberta. Victoria, as a postdoctoral researcher at North Carolina State University and the North Carolina Museum of Natural Sciences, then contacted Martin-Silverstone and the Royal BC Museum sent the specimen for analysis in collaboration with Mark Witton, a pterosaur expert at the University of Portsmouth. "The specimen is far from the prettiest or most complete pterosaur fossil you'll ever see, but it's still an exciting and significant find. It's rare to find pterosaur fossils at all because their skeletons were lightweight and easily damaged once they died, and the small ones are the rarest of all. But luck was on our side and several bones of this animal survived the preservation process. Happily, enough of the specimen was recovered to determine the approximate age of the pterosaur at the time of its death. By examining its internal bone structure and the fusion of its vertebrae we could see that, despite its small size, the animal was almost fully grown. The specimen thus seems to be a genuinely small species, and not just a baby or juvenile of a larger pterosaur type" said Witton. "The absence of small juveniles of large species—which must have existed—in the fossil record is evidence of a preservational bias against small pterosaurs in the Late Cretaceous. It adds to a growing set of evidence that the Late Cretaceous period was not dominated by large or giant species, and that smaller pterosaurs may have been well represented in this time. As with other evidence of smaller pterosaurs, the fossil specimen is fragmentary and poorly preserved: researchers should check collections more carefully for misidentified or ignored pterosaur material, which may enhance our picture of pterosaur diversity and disparity at this time," added Martin-Silverstone.
Dyke G.,University College Dublin |
Wang X.,University College Dublin |
Kaiser G.,Royal BC Museum
Canadian Journal of Earth Sciences | Year: 2011
Few fossil birds and non-avian dinosaurs are known from Mesozoic sediments bordering the eastern margin of the Pacific Ocean. Here, we describe additional remains of Late Cretaceous birds from a deep-water marine turbidite sequence of the Northumberland Formation exposed on Hornby Island, British Columbia. The bones described here are referable (based on hypothesized autapomorphies) to the Cretaceous avian lineages Enantiornithes and Ornithurae and fall into at least two size classes within either lineage. This suggests the presence of multiple taxa occurring within the Northumberland Formation.
Hope A.G.,U.S. Geological Survey |
Panter N.,Royal BC Museum |
Cook J.A.,University of New Mexico |
Talbot S.L.,U.S. Geological Survey |
Nagorsen D.W.,Royal BC Museum
Journal of Mammalogy | Year: 2014
North American water shrews, which have traditionally included Sorex alaskanus, S. bendirii, and S. palustris, are widely distributed through Nearctic boreal forests and adapted for life in semiaquatic environments. Molecular mitochondrial signatures for these species have recorded an evolutionary history with variable levels of regional divergence, suggesting a strong role of Quaternary environmental change in speciation processes. We expanded molecular analyses, including more-comprehensive rangewide sampling of specimens representing North American water shrew taxa, except S. alaskanus, and sequencing of 4 independent loci from the nuclear and mitochondrial genomes. We investigated relative divergence of insular populations along the North Pacific Coast, and newly recognized diversity from southwestern montane locations, potentially representing refugial isolates. Congruent independent genealogies, lack of definitive evidence for contemporary gene flow, and high support from coalescent species trees indicated differentiation of 4 major geographic lineages over multiple glacial cycles of the late Quaternary, similar to a growing number of boreal taxa. Limited divergence of insular populations suggested colonization following the last glacial. Characterization of southwestern montane diversity will require further sampling but divergence over multiple loci is indicative of a relictual sky-island fauna. We have reviewed and revised North American water shrew taxonomy including the recognition of 3 species within what was previously known as S. palustris. The possibility of gene flow between most distantly related North American water shrew lineages coupled with unresolved early diversification of this group and other sibling species reflects a complex but potentially productive system for investigating speciation processes. © 2014 American Society of Mammalogists.
Oliver P.G.,National Museum of Wales |
Frey M.A.,Royal BC Museum
Zootaxa | Year: 2014
Ascetoaxinus quatsinoensis sp. et gen. nov. is described from deep waters off the coast of Vancouver Island, British Co- lumbia, Canada. The shell of this species is quite unusual in that the margin of the lunule is distinctly scalloped, a feature not reported previously for the Thyasiroidea. Further investigation led to the discovery of another similarly scalloped shell, represented by the unique type specimen of Cryptodon ovoideus Dall, 1890, herein re-classified as Ascetoaxinus ovoidea (Dall, 1890). Results obtained from scanning electron microscopy reveal additional anatomical differences, in- cluding distinct gill structure, that distinguish A. quatsinoensis from other thyasirids examined. Morphological compari- sons of this new species to closely related taxa has resulted in a re-evaluation of the genera Conchocele Gabb, 1866, and Channelaxinus Valentich-Scott and Coan, 2012. Copyright © 2014 Magnolia Press.
PubMed | National Museum of Wales and Royal BC Museum
Type: Journal Article | Journal: Zootaxa | Year: 2014
Ascetoaxinus quatsinoensis sp. et gen. nov. is described from deep waters off the coast of Vancouver Island, British Columbia, Canada. The shell of this species is quite unusual in that the margin of the lunule is distinctly scalloped, a feature not reported previously for the Thyasiroidea. Further investigation led to the discovery of another similarly scalloped shell, represented by the unique type specimen of Cryptodon ovoideus Dall, 1890, herein re-classified as Ascetoaxinus ovoidea (Dall, 1890). Results obtained from scanning electron microscopy reveal additional anatomical differences, including distinct gill structure, that distinguish A. quatsinoensis from other thyasirids examined. Morphological comparisons of this new species to closely related taxa has resulted in a re-evaluation of the genera Conchocele Gabb, 1866, and Channelaxinus Valentich-Scott and Coan, 2012.
Kaiser G.,Royal BC Museum |
Watanabe J.,Kyoto University |
Johns M.,Royal BC Museum
Palaeontologia Electronica | Year: 2015
The discovery of an avian fossil, in the upper Oligocene Sooke Formation rocks on southwestern Vancouver Island, British Columbia, is the first example from Canada of the Plotopteridae, an extinct family that lived in the North Pacific from the late Eocene to the early Miocene. The fossil is a nearly complete, well-preserved coracoid that exhibits the diagnostic features of the family. Stemec suntokum is described as a new genus and species for this family of extinct, wing-propelled diving birds. Coracoids are exceptionally informative bones that lie at the focus of forces acting on the shoulder where they play a major role in avian locomotory biomechanics. The coracoid of Stemec has an unusually narrow, conical shaft that differs fundamentally from the broad, flattened coracoids of other avian groups. © 2015, Texas A and M University. All rights reserved.
News Article | December 18, 2015
A family out on a stroll along a Vancouver beach in Canada discovered fossilized remains of a 25-million-year-old flightless bird. The clavicle from the bird is now the second fossil discovered on southern Vancouver Island since 1895. The rare fossil was in good condition enabling researchers to identify it as an unknown variety of plotopterid, an extinct family that lived in the North Pacific from the late Eocene to the early Miocene period. Today, fossils from this type of flightless birds have only been found in the United States and Japan. When Gary Kaiser, a paleontologist and research associate at the Royal British Columbia (BC) Museum, got a hold of the fossil, he immediately looked into a local First Nations dictionary to look for an appropriate name for it. Hence, Kaiser and his colleague Junya Wantanabe of Kyoto University named the penguin-like bird as Stemec suntoku, which originates from the language of the T'Sou-Ke people. It means long-necked, black water bird. Fossils from birds are extraordinary because these are fragile. This makes these bones unable to withstand elements like heat or coldness unlike other fossils. Apparently, the sandstone and lack of water acidity contributed to the preservation of the fossil. The fossil was discovered by a father and two children when they went walking on the beach. The daughter discovered the fossil in a slab of rock. They immediately brought it to the museum for examination. Though Kaiser is convinced that the fossil is from an animal similar to a penguin, other scientists say that it looks more closely like cormorants, a species of black and diving sea birds. "It's a bit of a fight, but not unusual in biology because there's no way of telling," Kaiser added. The study announcing the discovery was published in the journal Palaeontologia Electronica. "We wish to thank L. Suntok and G. Suntok for donating the fossil of Stemec to the Royal BC Museum," the authors acknowledged in the study.