Linking the evolution of body shape and locomotor biomechanics in bird-line archosaurs

@article{Allen2013LinkingTE,
  title={Linking the evolution of body shape and locomotor biomechanics in bird-line archosaurs},
  author={Vivian R Allen and Karl T. Bates and Zhiheng Li and John R. Hutchinson},
  journal={Nature},
  year={2013},
  volume={497},
  pages={104-107}
}
Locomotion in living birds (Neornithes) has two remarkable features: feather-assisted flight, and the use of unusually crouched hindlimbs for bipedal support and movement. When and how these defining functional traits evolved remains controversial. However, the advent of computer modelling approaches and the discoveries of exceptionally preserved key specimens now make it possible to use quantitative data on whole-body morphology to address the biomechanics underlying this issue. Here we use… 

Figures from this paper

Relationships of mass properties and body proportions to locomotor habit in terrestrial Archosauria
TLDR
Digital volumetric models of 80 taxa are used to explore how mass properties and body proportions relate to each other and locomotor posture in archosaurs and facilitate the development of a quantitative predictive framework that can help assess gross locom motor posture in understudied or controversial taxa.
Maniraptoran pelvic musculature highlights evolutionary patterns in theropod locomotion on the line to birds
TLDR
Examination of the pelvis for osteological correlates of hind limb and tail musculature allowed reconstruction of primary locomotory muscles across theropods and their closest extant relatives and suggests that a more punctuated step in caudal decoupling occurred at or near the base of Maniraptora.
The relationship between sternum variation and mode of locomotion in birds
TLDR
This study lays the groundwork for estimating the locomotory abilities of paravian dinosaurs, the ancestors to Neornithes, by highlighting the importance of this critical element for avian flight, and will be useful for future work on the origin of flight along the dinosaur-bird lineage.
The influence of speed and size on avian terrestrial locomotor biomechanics: Predicting locomotion in extinct theropod dinosaurs
TLDR
The influences of speed and body size on kinematic and kinetic factors in birds are developed into a set of predictive relationships that may be applied to extinct, non-avian theropods.
New Perspectives on the Ontogeny and Evolution of Avian Locomotion.
TLDR
The ontogeny of avian locomotion is reviewed, highlighting how the developmental acquisition of flight in extant birds can improve the authors' understanding of form-function relationships in the avian body plan, and provide insight into the evolutionary origin of flight among extinct non-avian theropod dinosaurs.
Cancellous bone and theropod dinosaur locomotion. Part III—Inferring posture and locomotor biomechanics in extinct theropods, and its evolution on the line to birds
TLDR
The results of this study support the hypothesis that an upright femoral posture is correlated with bending-dominant bone loading and abduction-based muscular support of the hip, whereas a crouched femoral postures are correlated with torsion-DominantBone loading and long-axis rotation- based muscular support.
Walking Like Dinosaurs: Chickens with Artificial Tails Provide Clues about Non-Avian Theropod Locomotion
TLDR
The results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution.
Using step width to compare locomotor biomechanics between extinct, non-avian theropod dinosaurs and modern obligate bipeds
TLDR
Step width—the mediolateral distance between successive footfalls—was investigated with respect to speed (stride length) in non-avian theropod trackways of Late Triassic age, inferring a continuous locomotor repertoire, possibly including grounded running.
The evolution of pelvic limb muscle moment arms in bird-line archosaurs
TLDR
The authors' results reveal how, from the Triassic Period, bipedal theropod dinosaurs gradually modified their hindlimb form and function, shifting more from hip-based to knee-based locomotion and hip-abductor to hip-rotator balancing mechanisms inherited by birds.
Cellular preservation of musculoskeletal specializations in the Cretaceous bird Confuciusornis
The hindlimb of theropod dinosaurs changed appreciably in the lineage leading to extant birds, becoming more ‘crouched' in association with changes to body shape and gait dynamics. This postural
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 39 REFERENCES
The evolutionary continuum of limb function from early theropods to birds
TLDR
It is emphasised that many false dichotomies or categories have been applied to theropod form and function, and sometimes, these impede research progress, and a combination of techniques that emphasises integration of neontological and palaeontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables are needed.
Adductors, abductors, and the evolution of archosaur locomotion
TLDR
Fossil theropods document the stepwise evolution of a novel mechanism of limb adduction/abduction involving long-axis rotation of the femur, which accounts for the conspicuous absence of significant musculature ventral and dorsal to the hip joint in extant birds.
Experimental alteration of limb posture in the chicken (Gallus gallus) and its bearing on the use of birds as analogs for dinosaur locomotion
TLDR
The hypothesis that a postural change during early avian evolution could underlie the allometric differences seen between bird and nonavian dinosaur femora by requiring more robust femoral dimensions in birds due to an increase in torsion is supported.
A Computational Analysis of Limb and Body Dimensions in Tyrannosaurus rex with Implications for Locomotion, Ontogeny, and Growth
TLDR
It is concluded that adult T. rex had body masses around 6000–8000 kg, with the largest known specimen (“Sue”) perhaps ∼9500 kg, and that the limb “antigravity” muscles may have been as large as or even larger than those of ratite birds, which themselves have the most muscular limbs of any living animal.
Limb proportions and avian terrestrial locomotion
TLDR
It is concluded that birds (Archaeopteryx + crownclade Aves) are a subgroup of the theropod dinosaurs and feathers cannot be used to define birds, as is traditionally advocated.
Variation in Center of Mass Estimates for Extant Sauropsids and its Importance for Reconstructing Inertial Properties of Extinct Archosaurs
TLDR
Estimation of inertial properties for extant and extinct animals found considerable potential methodological errors related to assumed body segment orientation, what frames of reference are used to normalize COM for size‐independent comparisons among animals, and assumptions about tail shape, are found.
LOCOMOTOR MODULES AND THE EVOLUTION OF AVIAN FLIGHT
  • S. Gatesy, K. Dial
  • Biology, Psychology
    Evolution; international journal of organic evolution
  • 1996
TLDR
The term “locomotor module” is introduced to identify anatomical subregions of the musculoskeletal system that are highly integrated and act as functional units during locomotion and has produced the diverse locomotor abilities of modern birds.
Bipedalism, flight, and the evolution of theropod locomotor diversity
TLDR
This work addressed the hypothesis that bird hind limbs should be more disparate than those of non-avian theropods by visualizing one aspect of limb design, the proportions of the three main segments, using ternary diagrams, and shows that avian hind limb proportions are much more disparate.
Caudofemoral musculature and the evolution of theropod locomotion
TLDR
Osteological evidence of both origin and insertion indicates that a substantial caudofemoralis longus was present in archosaurs primitively and was retained in the clades Di- nosauria and Theropoda, and strongly suggests that details of the orientation (subhorizontal femur) and movement (primarily knee flexion) of the hind limb in extant birds are more properly viewed as derived, uniquely avian conditions.
Biplane wing planform and flight performance of the feathered dinosaur Microraptor gui
TLDR
This reconstruction shows that the wings of Microraptor could have resembled a staggered biplane configuration during flight, where the forewing formed the dorsal wing and the metatarsal wing formed the ventral one.
...
1
2
3
4
...