The size of the megatooth shark, Otodus megalodon (Lamniformes: Otodontidae), revisited

@article{Shimada2019TheSO,
  title={The size of the megatooth shark, Otodus megalodon (Lamniformes: Otodontidae), revisited},
  author={Kenshu Shimada},
  journal={Historical Biology},
  year={2019},
  volume={33},
  pages={904 - 911}
}
  • K. Shimada
  • Published 30 September 2019
  • Environmental Science, Geography
  • Historical Biology
ABSTRACT Otodus megalodon (Lamniformes: Otodontidae) is a gigantic late Neogene shark that lived nearly worldwide in tropical-temperate regions. Its gigantic teeth have captivated imaginations of the scientific community and general public alike, where the most commonly cited maximum size range of O. megalodon in scientific literature is 18–20 m in total length (TL). In this study, I reexamined the ontogenetic development of teeth and the quantitative relationships between TL and the crown… 

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References

SHOWING 1-10 OF 62 REFERENCES

A new elusive otodontid shark (Lamniformes: Otodontidae) from the lower Miocene, and comments on the taxonomy of otodontid genera, including the ‘megatoothed’ clade

TLDR
A new large otodontid lamniform shark, Megalolamna paradoxodon gen. nov., chronostratigraphically restricted to the early Miocene, is described based on isolated teeth found from five globally distributed localities.

The Early Pliocene extinction of the mega-toothed shark Otodus megalodon: a view from the eastern North Pacific

TLDR
All records of Otodus megalodon from post-Messinian marine strata from western North America are reviewed and a published dataset is reevaluated, thoroughly vetting each occurrence and justifying the geochronologic age of each, as well as excluding several dubious records.

The transition between Carcharocles chubutensis and Carcharocles megalodon (Otodontidae, Chondrichthyes): lateral cusplet loss through time

TLDR
This study helps to elucidate the timing of lateral cusplet loss in Carcharocles locally, and the rationale for this prolonged evolutionary transition remains unclear.

Regional endothermy as a trigger for gigantism in some extinct macropredatory sharks

  • H. Ferrón
  • Environmental Science, Geography
    PloS one
  • 2017
TLDR
It is proposed that regional endothermy was present in otodontids and some closely related taxa (cretoxyrhinids), playing an important role in the evolution of gigantism and in allowing an active mode of live.

When Did Carcharocles megalodon Become Extinct? A New Analysis of the Fossil Record

TLDR
The study of the time of extinction of C. megalodon provides the basis to improve the understanding of the responses of marine species to the removal of apex predators, presenting a deep-time perspective for the conservation of modern ecosystems.

The relationship between the tooth size and total body length in the goblin shark, Mitsukurina owstoni (Lamniformes: Mitsukurinidae)

TLDR
The results suggest that the CH for most teeth can be used to predict the TL, where an increase in the CH of each tooth through replacement is proportional to the increase in TL.

Body-size trends of the extinct giant shark Carcharocles megalodon: a deep-time perspective on marine apex predators

TLDR
The results suggest that (1) a selective pressure in predatory sharks for consuming a broader range of prey may favor larger individuals and produce left-skewed distributions on a geologic time scale; (2) body-size variations in cosmopolitan apex marine predators may depend on their interactions with geographically discrete communities; and (3) the inherent characteristics of shark species can produce stable sizes overGeologic time, regardless of the size trends of their lineages.

Registro de Carcharocles megalodon en el sector oriental de la Cuenca del Guadalquivir (Mioceno superior, Sur de España)

Tortonian diatomites of the San Felix Quarry (Porcuna), in the Eastern Guadalquivir Basin, have given isolated marine vertebrate remains that include a large shark tooth (123.96 mm from apex to the

Carcharodon megalodon from the Upper Miocene of Denmark, with comments on elasmobranch tooth enameloid: coronoi:n

https://doi.org/10.37570/bgsd-1983-32-01 C. megalodon, not previously known from deposits in Denmark, is recorded from a large, but imperfect tooth derived from the marine clay exposed at the type
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