Search Results - "Horner, John R."

First Reported Cases of Biomechanically Adaptive Bone Modeling in Non-Avian Dinosaurs by Cubo, Jorge, Woodward, Holly, Wolff, Ewan, Horner, John R

“…Predator confrontation or predator evasion frequently produces bone fractures in potential prey in the wild. Although there are reports of healed bone injuries…”
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A New Brachylophosaurin Hadrosaur (Dinosauria: Ornithischia) with an Intermediate Nasal Crest from the Campanian Judith River Formation of Northcentral Montana by Freedman Fowler, Elizabeth A, Horner, John R

“…Brachylophosaurini is a clade of hadrosaurine dinosaurs currently known from the Campanian (Late Cretaceous) of North America. Its members include: Acristavus…”
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Fusion Patterns in the Skulls of Modern Archosaurs Reveal That Sutures Are Ambiguous Maturity Indicators for the Dinosauria by Bailleul, Alida M, Scannella, John B, Horner, John R, Evans, David C

“…The sutures of the skulls of vertebrates are generally open early in life and slowly close as maturity is attained. The assumption that all vertebrates follow…”
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Maiasaura, a model organism for extinct vertebrate population biology: a large sample statistical assessment of growth dynamics and survivorship by Woodward, Holly N, Fowler, Elizabeth A. Freedman, Farlow, James O, Horner, John R

“…Fossil bone microanalyses reveal the ontogenetic histories of extinct tetrapods, but incomplete fossil records often result in small sample sets lacking…”
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Evolutionary trends in Triceratops from the Hell Creek Formation, Montana by Scannella, John B., Fowler, Denver W., Goodwin, Mark B., Horner, John R.

“…The placement of over 50 skulls of the well-known horned dinosaur Triceratops within a stratigraphic framework for the Upper Cretaceous Hell Creek Formation…”
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Extreme cranial ontogeny in the upper cretaceous dinosaur pachycephalosaurus by Horner, John R, Goodwin, Mark B

“…Extended neoteny and late stage allometric growth increase morphological disparity between growth stages in at least some dinosaurs. Coupled with relatively…”
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Dinosaur census reveals abundant Tyrannosaurus and rare ontogenetic stages in the Upper Cretaceous Hell Creek Formation (Maastrichtian), Montana, USA by Horner, John R, Goodwin, Mark B, Myhrvold, Nathan

“…A dinosaur census recorded during the Hell Creek Project (1999-2009) incorporates multiple lines of evidence from geography, taphohistory, stratigraphy,…”
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Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology by Woodward, Holly N, Horner, John R, Farlow, James O

“…Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct…”
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Misconceptions of sexual selection and species recognition: a response to Knell et al. and to Mendelson and Shaw by Padian, Kevin, Horner, John R.

“…► Sexual selection requires sexual dimorphism; this was integral to Darwin's original definition. ► Claims of sexual selection in extinct animals often rely on…”
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Osteohistological Evidence for Determinate Growth in the American Alligator by Woodward, Holly N, Horner, John R, Farlow, James O

“…An external fundamental system (EFS) is a form of bone microstructure present in the outermost cortex of long bones in animals that have attained skeletal…”
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Ontogenetic changes in the long bone microstructure in the nine-banded armadillo (Dasypus novemcinctus) by Heck, Christian Thomas, Varricchio, David J, Gaudin, Timothy J, Woodward, Holly N, Horner, John R

“…Analysis of ontogenetic changes in long bone microstructure aid in vertebrate life history reconstructions. Specifically, osteohistological examination of…”
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Paleontology: A Cock’s Comb on a Duck-Billed Dinosaur by Horner, John R.

“…A soft tissue structure has been discovered on the head of the duck-billed dinosaur Edmontosaurus. Its similarity to a cock’s comb and other sexually dimorphic…”
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Avian tail ontogeny, pygostyle formation, and interpretation of juvenile Mesozoic specimens by Rashid, Dana J., Surya, Kevin, Chiappe, Luis M., Carroll, Nathan, Garrett, Kimball L., Varghese, Bino, Bailleul, Alida, O’Connor, Jingmai K., Chapman, Susan C., Horner, John R.

“…The avian tail played a critical role in the evolutionary transition from long- to short-tailed birds, yet its ontogeny in extant birds has largely been…”
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Age and growth dynamics of Tyrannosaurus rex by Horner, John R., Padian, Kevin

“…T. rex…”
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Soft tissue and cellular preservation in vertebrate skeletal elements from the Cretaceous to the present by Schweitzer, Mary Higby, Wittmeyer, Jennifer L, Horner, John R

“…Tyrannosaurus rex…”
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Major cranial changes during Triceratops ontogeny by Horner, John R, Goodwin, Mark B

“…the well-known Late Cretaceous dinosaur distinguished by three horns and a massive parietal–squamosal frill. Our analysis is based on a growth series of 10…”
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Vertebral Adaptations to Large Body Size in Theropod Dinosaurs by Wilson, John P, Woodruff, D Cary, Gardner, Jacob D, Flora, Holley M, Horner, John R, Organ, Chris L

“…Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the…”
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A New Specimen of the Ornithischian Dinosaur Hesperosaurus mjosi from the Upper Jurassic Morrison Formation of Montana, U.S.A., and Implications for Growth and Size in Morrison Stegosaurs by Maidment, Susannah C. R, Woodruff, D. Cary, Horner, John R

“…Stegosauria is a clade of ornithischian dinosaurs characterized by a bizarre array of dermal armor that extends from the neck to the end of the tail. Two…”
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'Nedoceratops': an example of a transitional morphology by Scannella, John B, Horner, John R

“…The holotype and only specimen of the chasmosaurine ceratopsid dinosaur 'Nedoceratops hatcheri' has been the source of considerable taxonomic debate since its…”
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Relative growth rates of predator and prey dinosaurs reflect effects of predation by Cooper, Lisa Noelle, Lee, Andrew H, Taper, Mark L, Horner, John R

“…(MOR 549). Spatial locations of LAGs in the femoral and tibial transverse sections of MOR 549 were measured and circumferences were calculated. For each bone,…”
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