Theropod Locomotion

Farlow, James O.; Gatesy, Stephen M.; Holtz, Thomas R.; Hutchinson, John R.; Robinson, John

doi:10.1093/icb/40.4.640

Cited by 69 publications

(112 citation statements)

References 69 publications

Supporting

Mentioning

110

Contrasting

Order By: Relevance

“…Its bipedalism was inherited from the primitive dinosaurian condition, but received considerable modification in several subsequent ingroup clades. These modifications often appear in parallel, suggesting similar mechanical effects with regard to locomotion (Carrano, 2000;Farlow et al, 2000;Hutchinson and Gatesy, 2000).…”

Section: Functional and Evolutionary Implicationsmentioning

confidence: 84%

“…Given the close approximation of these bones in Tyrannosaurus (and other tetanurans), M. popliteus was likely restricted (relative to the primitive condition) to the region proximal to the fibular crest. Thus, the muscle would have originated from the lateral surface of the proximal tibia, posterior to the fibular crest, and inserted within the expansive medial fossa of the proximal fibula (as noted by Farlow et al, 2000). In Tyrannosaurus, this region is marked by a flat, ridged surface that faces posterolaterally.…”

Section: Popliteus (Pop)mentioning

confidence: 99%

“…The reduction of the plantar aponeurosis and the expansion of the flexor tubercles and extensor attachments on the pes are also likely correlated with the evolution of digitigrady, bipedalism, erect posture, and perhaps changes in lower limb kinematics as well. Reduction of the fibula reflects the increased consolidation of the lower limb (Farlow et al, 2000) as well as changes in lower leg muscle origins, such as the proximal restriction of M. popliteus. These changes probably signal a restriction of nonparasagittal motion of joints within the lower limb, such as movement of the fibula relative to the tibia or complex intratarsal motion.…”

Section: Functional and Evolutionary Implicationsmentioning

confidence: 99%

See 2 more Smart Citations

Pelvic and hindlimb musculature of Tyrannosaurus rex (Dinosauria: Theropoda)

Carrano

Hutchinson

2002

Journal of Morphology

Self Cite

227

619

View full text Add to dashboard Cite

In this article, we develop a new reconstruction of the pelvic and hindlimb muscles of the large theropod dinosaur Tyrannosaurus rex. Our new reconstruction relies primarily on direct examination of both extant and fossil turtles, lepidosaurs, and archosaurs. These observations are placed into a phylogenetic context and data from extant taxa are used to constrain inferences concerning the soft-tissue structures in T. rex. Using this extant phylogenetic bracket, we are able to offer well-supported inferences concerning most of the hindlimb musculature in this taxon. We also refrain from making any inferences for certain muscles where the resulting optimizations are ambiguous. This reconstruction differs from several previous attempts and we evaluate these discrepancies. In addition to providing a new and more detailed understanding of the hindlimb morphology of T. rex-the largest known terrestrial biped-this reconstruction also helps to clarify the sequence of character-state change along the line to extant birds.

show abstract

Section: Functional and Evolutionary Implicationsmentioning

confidence: 84%

Section: Popliteus (Pop)mentioning

confidence: 99%

Section: Functional and Evolutionary Implicationsmentioning

confidence: 99%

See 1 more Smart Citation

Pelvic and hindlimb musculature of Tyrannosaurus rex (Dinosauria: Theropoda)

Carrano

Hutchinson

2002

Journal of Morphology

Self Cite

227

619

View full text Add to dashboard Cite

show abstract

“…Because of proposed similarities in behaviour and habitat, the bipedal ostrich is a valuable model for the theoretical reconstruction of locomotor modes in theropod dinosaurs (Farlow et al, 2000;Gatesy, 1991). We hope these results contribute to this inquiry and perhaps add to the debate about toe reduction in avian species over the course of evolution.…”

Section: Introductionmentioning

confidence: 83%

Toe function and dynamic pressure distribution in ostrich locomotion

Schaller

D’Août

Villa

et al. 2011

Journal of Experimental Biology

121

View full text Add to dashboard Cite

SUMMARYThe ostrich is highly specialized in terrestrial locomotion and is the only extant bird that is both didactyl and exhibits a permanently elevated metatarsophalangeal joint. This extreme degree of digitigrady provides an excellent opportunity for the study of phalangeal adaptation towards fast, sustained bipedal locomotion. Data were gathered in a semi-natural setting with hand-raised, cooperative specimens. Dynamic pressure distribution, centre of pressure (CoP) trajectory and the positional interrelationship of the toes during stance phase were investigated using pedobarography. Walking and running trials shared a Jshaped CoP trajectory with greater localization of CoP origin as speed increased. Slight variations of 4th toe position in walking affect CoP origin and modulation of 4th toe pressure on the substrate allows correction of balance, primarily at the beginning of stance phase at lower speeds. Load distribution patterns differed significantly between slow and fast trials. In walking, the 3rd and particularly the 4th toe exhibited notable variation in load distribution with minor claw participation only at push-off. Running trials yielded a distinctly triangular load distribution pattern defined by the 4th toe tip, the proximal part of the 3rd toe and the claw tip, with the sharp point of the claw providing an essential traction element at push-off. Consistency of CoP trajectory and load distribution at higher speeds arises from dynamic stability effects and may also reflect stringent limitations to degrees of freedom in hindlimb joint articulation that contribute to locomotor efficiency. This novel research could aid in the reconstruction of theropod locomotor modes and offers a systemic approach for future avian pedobarographic investigations.

show abstract

“…caudofemoralis,'' but this muscle is not homologous to the M. caudofemoralis of saurians and birds (Appleton, 1928;Howell, 1938). In modern Aves, knee flexion is more important to locomotion than femoral retraction (Gatesy and Biewener, 1991;Carrano, 1998;Farlow et al, 2000), and the M. caudofemoralis is greatly reduced in most birds and altogether absent in others (Gatesy, 1990). In crocodilians and the majority of non-serpente squamates, however, the M. caudofemoralis is both the primary and the single largest retractor muscle of the hind limb (Snyder, 1962;Gatesy, 1990).…”

mentioning

confidence: 99%

The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non‐Avian Theropods

Persons

Currie

2010

The Anatomical Record

163

View full text Add to dashboard Cite

Unlike extant birds and mammals, most non-avian theropods had large muscular tails, with muscle arrangements similar to those of modern reptiles. Examination of ornithomimid and tyrannosaurid tails revealed sequential diagonal scarring on the lateral faces of four or more hemal spines that consistently correlates with the zone of the tail just anterior to the disappearance of the vertebral transverse processes. This sequential scarring is interpreted as the tapering boundary between the insertions of the M. caudofemoralis and the M. ilioischiocaudalis. Digital muscle reconstructions based on measurements of fossil specimens and dissections of modern reptiles showed that the M. caudofemoralis of many non-avian theropods was exceptionally large. These high caudofemoral mass estimates are consistent with the elevation of the transverse processes of the caudal vertebra above the centrum, which creates an enlarged hypaxial region. Dorsally elevated transverse processes are characteristic of even primitive theropods and suggest that a large M. caudofemoralis is a basal characteristic of the group. In the genus Tyrannosaurus, the mass of the M. caudofemoralis was further increased by dorsoventrally lengthening the hemal arches. The expanded M. caudofemoralis of Tyrannosaurus may have evolved as compensation for the animal's immense size. Because the M. caudofemoralis is the primary hind limb retractor, large M. caudofemoralis masses and the resulting contractile force and torque estimates presented here indicate a sizable investment in locomotive muscle among theropods with a range of body sizes and give new evidence in favor of greater athleticism, in terms of overall cursoriality, balance, and turning agility. Anat Rec, 294:119-131, 2011. V V C 2010 Wiley-Liss, Inc.

show abstract

Theropod Locomotion

Cited by 69 publications

References 69 publications

Pelvic and hindlimb musculature of Tyrannosaurus rex (Dinosauria: Theropoda)

Pelvic and hindlimb musculature of Tyrannosaurus rex (Dinosauria: Theropoda)

Toe function and dynamic pressure distribution in ostrich locomotion

The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non‐Avian Theropods

Contact Info

Product

Resources

About