Physiological constraints on body size distributions in Crocodyliformes

  title={Physiological constraints on body size distributions in Crocodyliformes},
  author={William Gearty and Jonathan L. Payne},
At least 26 species of crocodylian populate the globe today, but this richness represents a minute fraction of the diversity and disparity of Crocodyliformes. Fossil forms are far more varied, spanning from erect, fully terrestrial species to flippered, fully marine species. To quantify the influence of a marine habitat on the directionality, rate, and variance of evolution of body size in Crocodyliformes and thereby identify underlying selective pressures, we compiled a database of body sizes… 

Body Size Evolution in Crocodylians and Their Extinct Relatives

Crocodylians are currently facing evolutionary decline. This is evinced by the rich fossil record of their extinct relatives, crocodylomorphs, which show not only significantly higher levels of

Reconstructed evolutionary patterns for crocodile-line archosaurs demonstrate impact of failure to log-transform body size data

The analytical results of Stockdale & Benton5 are strongly influenced by a methodological error in their body size index, that they chose not to log-transform measurement data prior to analyses.

Ecological and evolutionary trends of body size in Pristimantis frogs, the world's most diverse vertebrate genus

It was found that the models that best explained body size in males, females, and SSD contained environmental variations in temperature, precipitation, and elevation as predictors, and body size has evolved toward an optimum with a decelerating rate of evolution differentiated between the large Pristimantis clades.

Anthropogenic disruptions to longstanding patterns of trophic-size structure in vertebrates

Diet and body mass are inextricably linked in vertebrates: while herbivores and carnivores have converged on much larger sizes, invertivores and omnivores are, on average, much smaller, leading to a

Ecological opportunity and the rise and fall of crocodylomorph evolutionary innovation

This macroevolutionary study of skull and jaw shape disparity shows that crocodylomorph ecomorphological variation peaked in the Cretaceous, before declining in theCenozoic, and the rise and fall of disparity was associated with great heterogeneity in evolutionary rates.

Ecological Filtering and Exaptation in the Evolution of Marine Snakes

There is strong evidence of ecological filtering for nonmarine ancestors that were already viviparous, had slightly larger than average body sizes, and lived in environments with higher-than-average temperatures and lower- than-average elevations.

Vertebrae-Based Body Length Estimation in Crocodylians and Its Implication for Sexual Maturity and the Maximum Sizes

  • M. IijimaT. Kubo
  • Environmental Science, Biology
    Integrative organismal biology
  • 2020
It was shown that most extant crocodylians reach sexual maturity before closure of precaudal NC sutures, and the upper or lower limit of the species maximum sizes can be determined from CLs and states of NC suture closure.

Ecological Drivers of Carnivoran Body Shape Evolution

  • Chris J. Law
  • Environmental Science, Biology
    The American Naturalist
  • 2021
AbstractMorphological diversity is often attributed as adaptations to distinct ecologies, but although biologists have long hypothesized that distinct ecology drive the evolution of body shape, these studies suggest that body shape can be influenced by multiple ecologies.

Evolutionary rates of body-size-related genes and ecological factors involved in driving body size evolution of squamates

Comparative genomic analyses of 101 body-size-related genes from 28 reptilian genomes laid a foundation for a comprehensive understanding of genetic mechanisms of body size evolution in squamates during the process of adapting to terrestrial life.

Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem

A new morphological dataset for Crocodylia is presented based on a critical reappraisal of published crocodylian character data matrices and extensive firsthand observations of a global sample of croc Codylians, which robustly recover Gavialis as more closely related to Tomistoma than to other extant cro codylians for the first time based on morphology alone.

The multi-peak adaptive landscape of crocodylomorph body size evolution

Shifts between macroevolutionary regimes provide a better explanation of crocodylomorph body size evolution than do climatic factors, suggesting a central role for lineage-specific adaptations rather than climatic forcing.

Body size estimation and evolution in metriorhynchid crocodylomorphs: Implications for species diversification and niche partitioning

The scaling of crania and femora to total body length of metriorhynchids is noticeably different from that of extant crocodylians, indicating that extant croCodylian are not ideal proxies for size reconstruction of extinct taxa that deviate from their semi-aquatic morphotype.

The evolution of island gigantism and body size variation in tortoises and turtles

This work found strong evidence for separate, larger optimal body sizes for sea turtles and island tortoises, the latter showing support for the rule of island gigantism in non-mammalian amniotes.

Dinosaurs, dragons, and dwarfs: The evolution of maximal body size

The body mass of the top species was found to increase with increasing land area, with a slope similar to that of the relation between body mass and home range area, suggesting that maximum body size is determined by the number of home ranges that can fit into a given land area.

Energetic tradeoffs control the size distribution of aquatic mammals

The evolutionary trajectories of body size in aquatic mammals are examined through both comparative phylogenetic analysis and examination of the fossil record to indicate that the evolution of an aquatic lifestyle is driving three of the four extant aquatic mammal clades toward a size attractor at ∼500 kg.

Big-headed marine crocodyliforms and why we must be cautious when using extant species as body length proxies for long-extinct relatives

Examination and regression analyses of the best preserved teleosaurid skeletons demonstrates that they were smaller than previously thought, with no known specimen exceeding 7.2 m in length; and that they had proportionally large skulls, and proportionally short femora, when compared to body length.

The macroevolutionary relationship between diet and body mass across mammals

Use of generalized Ornstein–Uhlenbeck models and data on over 1350 species of mammal reveal that evolutionary changes in body mass are consistently associated with dietary changes across mammals, and that herbivores are substantially heavier than other dietary groups and that omnivore are frequently intermediate in mass between herbivore and carnivores.

Evolutionary structure and timing of major habitat shifts in Crocodylomorpha

This analysis suggests at least four independent origins of saltwater tolerance in Crocodylomorpha, which is at least three independent shifts from terrestrial to aquatic and numerous other habitat transitions into the marine realm.

Environmental drivers of crocodyliform extinction across the Jurassic/Cretaceous transition

A comprehensive analysis of crocodyliform biodiversity through the Jurassic/Cretaceous (J/K) transition is presented using subsampling and phylogenetic approaches and maximum-likelihood methods to fit models of extrinsic variables to assess what mediated these patterns.

The Evolution and Distribution of Species Body Size

A simple model of cladogenetic diffusion over evolutionary time that omits explicit mechanisms for interspecific competition and other microevolutionary processes, yet fully explains the shape of the distribution of species body size within taxonomic groups is provided.