Cautionary tales on the use of proxies to estimate body size and form of extinct animals

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(9)

Published: Sept. 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.

Language: 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

Palaeontologia Electronica, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 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.

Language: Английский

Uma proposta de uso da Paleontologia para ensinar Matemática

Terrae Didatica, Journal Year: 2025, Volume and Issue: 21(00), P. e025006 - e025006

Published: April 25, 2025

Introdução. A Paleontologia, quando associada a ferramentas tecnológicas, pode enriquecer o ensino básico ao integrar diferentes disciplinas, promover contextualização do conhecimento e estimular pensamento crítico dos estudantes. Objetivo. Este trabalho apresenta uma atividade interdisciplinar aplicada alunos 2º ano Ensino Médio de escola pública estadual Mato Grosso, na qual conceitos matemáticos foram explorados por meio da reconstrução tamanho corporal Pycnonemosaurus nevesi, um dinossauro carnívoro encontrado região. Metodologia. Foram utilizados fotogrametria, modelagem computacional impressão 3D, permitindo que os estudantes trabalhassem com Matrizes Escalas forma prática. Resultados. Os resultados evidenciam abordagem adotada não apenas melhorou compreensão matemática, mas também aumentou engajamento estudantes, despertando interesse pela Paleontologia aplicação das tecnologias no ensino. Conclusão. promoveu reflexões sobre valor patrimônio fossilífero brasileiro suas potencialidades interdisciplinar, tornando aprendizado mais dinâmico, acessível contextualizado.