Biomechanics of ossified tendons in ornithopod dinosaurs

  title={Biomechanics of ossified tendons in ornithopod dinosaurs},
  author={Christopher Lee Organ},
  • C. Organ
  • Published in Paleobiology 1 December 2006
  • Biology, Geography, Environmental Science
Abstract Spinal ossified tendons are a defining character for Ornithischia, one of the two major clades of dinosaurs. The function of these bony rods has remained a mystery since their first detailed description in 1886. Qualitative approaches to understand ossified tendon function have resulted in different ecological and behavioral interpretations for ornithopod dinosaurs. To evaluate ossified tendon function, this study constructed finite element models of the vertebral column for two… 

Morphology and Histology of Lattice‐like Ossified Epaxial Tendons in Psittacosaurus (Dinosauria: Ceratopsia)

Comparative study indicates that a lattice-like arrangement of three-layered epaxial tendons is widely distributed in Cerapoda, and implies that the different morphology of ossified tendons in dinosaurs may be associated with adaptive aspects of their paleobiology, not simply a side effect of skeletal ossification.

Vertebral Adaptations to Large Body Size in Theropod Dinosaurs

Novel histologic and phylogenetic evidence is shown that neural spine projections were a physiological response to biomechanical stress in large-bodied theropod species, and a new association of interspinal ligament metaplasia in Theropoda with large body size is added.

Nuchal ligament reconstructions in diplodocid sauropods support horizontal neck feeding postures

This study proposes that the apices of the bifurcated spines were the anchoring points for a split nuchal ligament, and that the trough of b ifurcation was predominantly filled with interspinal ligaments.

Finite Element Analyses of Ankylosaurid Dinosaur Tail Club Impacts

It is concluded that tail swinging‐behavior may have been possible in Euoplocephalus, but more sophisticated models incorporating flexible constraints are needed to support this hypothesis.

The homology and origins of intermuscular bones in fishes: phylogenetic or biomechanical determinants?

It is found that there is a phylogenetic signal in the distribution of four out of six ossified tendons, but that after correcting for phylogenetic relationships there are still morphological predictors for the presence of all ossify tendons.

Different ossification patterns of intermuscular bones in fish with different swimming modes

The ossification of intermuscular bones in teleost fish appears to be induced by mechanical force loadings produced by swimming.

Virtual palaeontology: Gait reconstruction of extinct vertebrates using high performance computing

This paper documents the use of an 8000 core computer to produce mechanically and physiologically plausible gaits and trackway patterns for a sub-adult dinosaur (Edmontosaurus annectens), evaluating a large range of locomotor possibilities in terms of running speed.

Osteology of a Near-Complete Skeleton of Tenontosaurus tilletti (Dinosauria: Ornithopoda) from the Cloverly Formation, Montana, USA

The character diagnosis of Tenontosaurus tilletti has been revised and redefined into a more robust and quantifiable state, and several of the synapomorphies are out-dated and deemed redundant in favour of a more quantifiable approach.

Description and etiology of paleopathological lesions in the type specimen of Parasaurolophus walkeri (Dinosauria: Hadrosauridae), with proposed reconstructions of the nuchal ligament

The history of reconstructions for Parasaurolophus walkeri is reviewed, showing how erroneous misconceptions have been perpetuated over time or have led to the development of new hypotheses, including the wide neck model supported in the current research.




Despite various anatomical locations and large differences in body size, ossified tendons were found to possess uniform microstructure even in specimens that do not normally experience intratendinous ossification (such as Spinostropheus and Camarasaurus).

Thoracic epaxial muscles in living archosaurs and ornithopod dinosaurs.

  • C. Organ
  • Biology, Environmental Science
    The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology
  • 2006
A phylogenetic perspective is used to determine muscle homologies in living archosaurs (birds and crocodylians), evaluate how the apparent disparity evolved, and reconstruct the thoracic epaxial muscles in ornithopod dinosaurs.

Caudofemoral musculature and the evolution of theropod locomotion

  • S. Gatesy
  • Biology, Environmental Science
  • 1990
Osteological evidence of both origin and insertion indicates that a substantial caudofemoralis longus was present in archosaurs primitively and was retained in the clades Dinosauria and Theropoda, and strongly suggests that details of the orientation (subhorizontal femur) and movement of the hind limb in extant birds are more properly viewed as derived, uniquely avian conditions, rather than as retentions of an ancestral dinosaurian pattern.

The postcranial skeleton of the ornithopod dinosaur Tenontosaurus tilletti

ABSTRACT Tenontosaurus tilletti is a moderate-sized ornithopod dinosaur from the Lower Cretaceous (Aptian–Albian) Cloverly Formation in Montana and Wyoming. Tenontosaurus remains are abundant. The

Intratendinous ossification in birds: A review

Interpretation of structural elements of the avian musculoskeletal system and their pattern among avian taxa at different systematic levels is reviewed with regard to age‐related changes in tendon, form features in avian phylogeny, and adaptive features in biomechanics and kinematics of locomotion.

Appendicular myology of the hadrosaurian dinosaur Maiasaura peeblesorum from the Late Cretaceous (Campanian) of Montana

  • D. Dilkes
  • Environmental Science
    Transactions of the Royal Society of Edinburgh: Earth Sciences
  • 1999
Abstract Musculature of the pectoral and pelvic appendages and girdles of adult and nestling Maiasaura peeblesorum (Dinosauria: Ornithischia: Hadrosauridae) from the Late Cretaceous of Montana is

Homologies of the transversospinalis muscles in the anterior presacral region of Sauria (crown Diapsida)

It is suggested here that the lepidosaurian articulo‐parietalis part of m.

In vivo locomotor strain in the hindlimb bones of alligator mississippiensis and iguana iguana: implications for the evolution of limb bone safety factor and non-sprawling limb posture

  • BlobBiewener
  • Biology
    The Journal of experimental biology
  • 1999
Measurements of in vivo locomotor strain from the limb bones of lizard and crocodilian species, animals from previously unsampled phylogenetic lineages with non-parasagittal limb posture and kinematics suggest that, in some lineages, strain magnitudes may not have been maintained at constant levels through the evolution of a non-sprawling posture.

An electromyographic analysis of hindlimb function in Alligator during terrestrial locomotion

  • S. Gatesy
  • Biology, Medicine
    Journal of morphology
  • 1997
The neuromuscular control of the hindlimb of American alligators walking on a treadmill was analyzed using simultaneous electromyography and cineradiography to discern the interplay of muscles mediating hip and knee movement during the high walk.

Tensile properties of calcified and uncalcified avian tendons

The mechanical properties of turkey and heron leg tendons have been investigated in dynamic tensile tests and the contribution made by elastic strain energy storage to lowering the cost of running is reduced.