Estimating body volumes and surface areas of animals from cross-sections DOI Creative Commons
Ruizhe Jackevan Zhao

PeerJ, Год журнала: 2024, Номер 12, С. e17479 - e17479

Опубликована: Май 28, 2024

Background Body mass and surface area are among the most important biological properties, but such information is lacking for some extant organisms extinct species. Numerous methods have been developed body size estimation of animals this reason. There two main categories mass-estimating approaches: extant-scaling approaches volumetric-density approaches. Extant-scaling determine relationships between linear skeletal measurements using regression equations. Volumetric-density approaches, on other hand, all based models. The models various types, including physical models, 2D images, 3D virtual reconstructions. Once constructed, their volumes acquired Archimedes’ Principle, math formulae, or software. Then densities assigned to convert masses. acquisition similar volume by changing formulae software commands. This article presents a new approach called cross-sectional method (CSM). Methods CSM integrates cross-sections estimate accurately. It requires side view dorsal/ventral image, series silhouettes perform calculation. To evaluate performance CSM, (Graphic Double Integration (GDI) Paleomass) compared with it. Results produces very accurate results, average error rates around 0.20% in 1.21% respectively. has higher accuracy than GDI Paleomass estimating areas irregular-shaped structures. Discussion Most previous assume an elliptical superelliptical approximation animal cross-sections. Such does not always good performance. processes true profiles directly rather approximating can deal any shape. process objects that gradually study also suggests more attention should be paid careful otherwise serious errors may introduced during estimations. Combined modeling techniques, considered as alternative under certain conditions. reduce complexity making reconstructions while ensuring reliability results.

Язык: Английский

Reassessment of the possible size, form, weight, cruising speed, and growth parameters of the extinct megatooth shark, Otodus megalodon (Lamniformes: Otodontidae), and new evolutionary insights into its gigantism, life history strategies, ecology, and extinction DOI Creative Commons
Kenshu Shimada, Ryosuke Motani,

Jake J. Wood

и другие.

Palaeontologia Electronica, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Otodus megalodon (Lamniformes: Otodontidae) is an iconic Neogene shark, but the lack of well-preserved skeletons has hampered our understanding various aspects its biology. Here, we reassess some biological properties using a new approach, based on known vertebral specimens O. and 165 species extinct extant neoselachian sharks across ten orders. Using median neurocranial caudal fin proportions relative to trunk proportion among non-mitsukurinid/non-alopiid lamniforms, show that could have had slender body possibly reached about 24.3 m in length. Allometric considerations indicate stout plan like white shark (Carcharodon carcharias) for incurred excessive hydrodynamic costs, further supporting interpretation likely slenderer than C. carcharias. A 24.3-m-long may weighed around 94 t, with estimated cruising speed 2.1-3.5 km h-1. reanalysis growth bands suggests size at birth 3.6-3.9 megalodon, previous interpretations ovoviviparity embryos' intrauterine oophagous behavior, less need nursery areas. Additional inferred patterns corroborated by fossil record support hypothesis emergence carcharias during Early Pliocene least partly responsible demise due competition resources. These are working hypotheses expected serve as reasonable reference points future studies biology megalodon.

Язык: Английский

Процитировано

2
Cautionary tales on the use of proxies to estimate body size and form of extinct animals DOI Creative Commons
Joel H. Gayford, Russell K. Engelman, Phillip C. Sternes

и другие.

Ecology and Evolution, Год журнала: 2024, Номер 14(9)

Опубликована: Сен. 1, 2024

Abstract Body size is of fundamental importance to our understanding extinct organisms. Physiology, ecology and life history are all strongly influenced by body shape, which ultimately determine how a species interacts with its environment. Reconstruction form in animals provides insight into the dynamics underlying community composition faunal turnover past ecosystems broad macroevolutionary trends. Many known only from incomplete remains, necessitating use anatomical proxies reconstruct form. Numerous limitations affecting appropriateness these often overlooked, leading controversy downstream inaccuracies studies for reconstructions represent key input data. In this perspective, we discuss four prominent case ( Dunkleosteus , Helicoprion Megalodon Perucetus ) proxy taxa have been used estimate shape fragmentary remains. We synthesise results other nuances validity taxon selection when reconstructing organisms, as well mitigation measures that can ensure most appropriate proxy. argue precautionary necessary maximise robustness better evolutionary ecological inferences.

Язык: Английский

Процитировано

6
Estimating body volumes and surface areas of animals from cross-sections DOI Creative Commons
Ruizhe Jackevan Zhao

PeerJ, Год журнала: 2024, Номер 12, С. e17479 - e17479

Опубликована: Май 28, 2024

Background Body mass and surface area are among the most important biological properties, but such information is lacking for some extant organisms extinct species. Numerous methods have been developed body size estimation of animals this reason. There two main categories mass-estimating approaches: extant-scaling approaches volumetric-density approaches. Extant-scaling determine relationships between linear skeletal measurements using regression equations. Volumetric-density approaches, on other hand, all based models. The models various types, including physical models, 2D images, 3D virtual reconstructions. Once constructed, their volumes acquired Archimedes’ Principle, math formulae, or software. Then densities assigned to convert masses. acquisition similar volume by changing formulae software commands. This article presents a new approach called cross-sectional method (CSM). Methods CSM integrates cross-sections estimate accurately. It requires side view dorsal/ventral image, series silhouettes perform calculation. To evaluate performance CSM, (Graphic Double Integration (GDI) Paleomass) compared with it. Results produces very accurate results, average error rates around 0.20% in 1.21% respectively. has higher accuracy than GDI Paleomass estimating areas irregular-shaped structures. Discussion Most previous assume an elliptical superelliptical approximation animal cross-sections. Such does not always good performance. processes true profiles directly rather approximating can deal any shape. process objects that gradually study also suggests more attention should be paid careful otherwise serious errors may introduced during estimations. Combined modeling techniques, considered as alternative under certain conditions. reduce complexity making reconstructions while ensuring reliability results.

Язык: Английский

Процитировано

1