Downsizing a giant: re-evaluating
            <i>Dreadnoughtus</i>
            body mass

Bates, Karl T.; Falkingham, Peter L.; Macaulay, Sophie; Brassey, Charlotte A.; Maidment, Susannah C. R.

doi:10.1098/rsbl.2015.0215

Cited by 48 publications

(74 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…; Bates et al . ) and perhaps 90 tonnes ( Argentinosaurus , herein) in giant sauropods (Table ). The regimes relevant to these extremely large and extremely small body sizes are both unique, having each evolved only once among Mesozoic dinosaurs (Fig.…”

Section: Discussionmentioning

confidence: 91%

See 1 more Smart Citation

Cope's rule and the adaptive landscape of dinosaur body size evolution

et al. 2017

View full text Add to dashboard Cite

The largest known dinosaurs weighed at least 20 million times as much as the smallest, indicating exceptional phenotypic divergence. Previous studies have focused on extreme giant sizes, tests of Cope's rule, and miniaturization on the line leading to birds. We use non-uniform macroevolutionary models based on Ornstein-Uhlenbeck and trend processes to unify these observations, asking: what patterns of evolutionary rates, directionality and constraint explain the diversification of dinosaur body mass? We find that dinosaur evolution is constrained by attraction to discrete body size optima that undergo rare, but abrupt, evolutionary shifts. This model explains both the rarity of multilineage directional trends, and the occurrence of abrupt directional excursions during the origins of groups such as tiny pygostylian birds and giant sauropods. Most expansion of trait space results from rare, constraint-breaking innovations in just a small number of lineages. These lineages shifted rapidly into novel regions of trait space, occasionally to small sizes, but most often to large or giant sizes. As with Cenozoic mammals, intermediate body sizes were typically attained only transiently by lineages on a trajectory from small to large size. This demonstrates that bimodality in the macroevolutionary adaptive landscape for land vertebrates has existed for more than 200 million years.

show abstract

Section: Discussionmentioning

confidence: 91%

“…; Woodruff & Foster ; Bates et al . ) and on framing hypotheses of the physiological, environmental, ecological and life history factors that made large sizes possible (Alexander ; Janis & Carrano ; Burness et al . ; Sander & Clauss ; O'Connor ; Sander et al .…”

Section: Abbreviationsmentioning

confidence: 99%

Cope's rule and the adaptive landscape of dinosaur body size evolution

et al. 2017

View full text Add to dashboard Cite

show abstract

“…There are two principal methods of body mass estimate in sauropods: long bone circumference and volumetric reconstruction (Bates et al, 2015;Carballido et al, 2017). Both these methods are not applicable for the body mass estimate in Volgatitan gen. nov. because of its incompleteness.…”

Section: Body Size Of Volgatitanmentioning

confidence: 99%

The oldest titanosaurian sauropod of the Northern Hemisphere

Alexander

Vladimir

2018

BioComm

View full text Add to dashboard Cite

Volgatitan simbirskiensis, gen. et sp. nov., is described based on a series of anterior and middle caudal vertebrae from a single individual discovered in the Lower Cretaceous (upper Hauterivian, Speetoniceras versicolor ammonite Zone) marine deposits at Slantsevy Rudnik vertebrate locality near Ulyanovsk City, Russia. The new taxon is characterized by strongly procoelous anterior and middle caudal vertebrae, a long centrum of the first caudal vertebra, a strong ventral ridge in the anterior and middle caudal vertebrae, a neural arch positioned at the anterior half of the centrum, hyposphene-hypantrum articulation in the anterior caudal vertebrae, and somphospondylous bone texture. Phylogenetic analysis places the new taxon as a lithostrotian titanosaur, a basal member of the lineage leading to the Lognkosauria. This lineage previously contained only South American taxa with body mass reaching 60-70 tons. Volgatitan gen. nov. is the first European and the geologically oldest representative of this lineage. Its body mass is estimated as 17.3 tons. Discovery of Volgatitan gen. nov. suggests that the lithostrotian lineage leading to the Lognkosauria had a wider distribution in the Early Cretaceous and became extinct everywhere except South America by the end of the Early Cretaceous. Citation: Citation: Averianov, A. and Efimov, V. 2018. The oldest titanosaurian sauropod of the Northern Hemisphere. Bio. Comm. 63(3): 145-162. https://doi.

show abstract

“…; Bates et al. , ), where in some cases the discrepancies are appreciable (for example up to 16% in extant taxa, Allen et al. ).…”

Section: Introductionmentioning

confidence: 99%

“…Comparisons are often made between physical measurements of body mass and values predicted from digital volumetric models (e.g. Henderson, 2006;Hutchinson et al 2007;Allen et al 2009;Bates et al 2009Bates et al , 2015, where in some cases the discrepancies are appreciable (for example up to 16% in extant taxa, Allen et al 2009b). However, assessing the ability of a model to predict body mass accurately does not indicate how accurately the model is able to predict CoM.…”

Section: Introductionmentioning

confidence: 99%

A quantitative evaluation of physical and digital approaches to centre of mass estimation

2017

Self Cite

View full text Add to dashboard Cite

Centre of mass is a fundamental anatomical and biomechanical parameter. Knowledge of centre of mass is essential to inform studies investigating locomotion and other behaviours, through its implications for segment movements, and on whole body factors such as posture. Previous studies have estimated centre of mass position for a range of organisms, using various methodologies. However, few studies assess the accuracy of the methods that they employ, and often provide only brief details on their methodologies. As such, no rigorous, detailed comparisons of accuracy and repeatability within and between methods currently exist. This paper therefore seeks to apply three methods common in the literature (suspension, scales and digital modelling) to three ‘calibration objects’ in the form of bricks, as well as three birds to determine centre of mass position. Application to bricks enables conclusions to be drawn on the absolute accuracy of each method, in addition to comparing these results to assess the relative value of these methodologies. Application to birds provided insights into the logistical challenges of applying these methods to biological specimens. For bricks, we found that, provided appropriate repeats were conducted, the scales method yielded the most accurate predictions of centre of mass (within 1.49 mm), closely followed by digital modelling (within 2.39 mm), with results from suspension being the most distant (within 38.5 mm). Scales and digital methods both also displayed low variability between centre of mass estimates, suggesting they can accurately and consistently predict centre of mass position. Our suspension method resulted not only in high margins of error, but also substantial variability, highlighting problems with this method.

show abstract

Downsizing a giant: re-evaluating Dreadnoughtus body mass

Cited by 48 publications

References 10 publications

Cope's rule and the adaptive landscape of dinosaur body size evolution

Cope's rule and the adaptive landscape of dinosaur body size evolution

The oldest titanosaurian sauropod of the Northern Hemisphere

A quantitative evaluation of physical and digital approaches to centre of mass estimation

Contact Info

Product

Resources

About