Insight into the evolutionary assemblage of cranial kinesis from a Cretaceous bird

eLife, Journal Year: 2022, Volume and Issue: 11

Published: Dec. 5, 2022

The independent movements and flexibility of various parts the skull, called cranial kinesis, are an evolutionary innovation that is found in living vertebrates only some squamates crown birds considered to be a major factor underpinning much enormous phenotypic ecological diversity birds, most diverse group extant amniotes. Compared postcranium, our understanding assemblage characteristic modern bird skull has been hampered by sparse fossil records early materials, with competing hypotheses regarding development kinesis among members avialans. Here, detailed three-dimensional reconstruction Early Cretaceous enantiornithine Yuanchuavis kompsosoura allows for its in-depth description, including elements poorly known early-diverging avialans but central deciphering mosaic assembly features required avian kinesis. Our shows functional conservation temporal palatal regions retaining ancestral theropod dinosaurian configuration within this otherwise derived volant bird. Geometric morphometric analysis palatine suggests loss jugal process represents first step structural modifications element leading kinetic condition. mixture plesiomorphic structures together avialan rostrum postcranial skeleton encapsulated manifests key role mosaicism experimentation diversification.

Language: Английский

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Origin of the avian predentary and evidence of a unique form of cranial kinesis in Cretaceous ornithuromorphs

Proceedings of the National Academy of Sciences, Journal Year: 2019, Volume and Issue: 116(49), P. 24696 - 24706

Published: Nov. 18, 2019

The avian predentary is a small skeletal structure located rostral to the paired dentaries found only in Mesozoic ornithuromorphs. evolution and function of this enigmatic element unknown. Skeletal tissues forming lower jaws basal ornithuromorph Yanornis martini are identified using computed-tomography, scanning electron microscopy, histology. On basis these data, we propose hypotheses for development, structure, element. composed trabecular bone. convex caudal surface articulates with rostromedial concavities on dentaries. These articular surfaces covered by cartilage, which divided into 3 discrete patches: 1 cartilage 2 symphyseal cartilages. mechanobiology suggests both compression kinesis were present at predentary–dentary joint, therefore suggesting yet unknown form cranial kinesis. Ontogenetic processes formation occurring within extant taxa do not suggest originates dentaries, nor Meckel’s cartilage. We hypothesize that biomechanically induced sesamoid arose soft connective mandibular canal hosting alveolar nerve dentary teeth proprioceptive. This whole system may have increased foraging efficiency. apparently coevolved an edentulous portion premaxilla, representing unique kinetic morphotype combined functional beak persisted successfully ∼60 million years.

Language: Английский

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Cranial osteology and palaeobiology of the Early Cretaceous birdJeholornis prima(Aves: Jeholornithiformes)

Zoological Journal of the Linnean Society, Journal Year: 2022, Volume and Issue: 198(1), P. 93 - 112

Published: Oct. 24, 2022

Abstract Jeholornis is a representative of the earliest-diverging bird lineages, providing important evidence anatomical transitions involved in origins. Although ~100 specimens have been reported, its cranial morphology remains poorly documented owing to poor two-dimensional preservation, limiting our understanding and ecology key avian lineage Jeholornithiformes, addition evolution during origin early birds. Here, we provide detailed description osteology prima, based primarily on high-quality, three-dimensional data recently reported specimen. New information confirms overall plesiomorphic skull, with exception more specialized rostrum. Data from large sample size reveal dental formula J. prima be 0–2–3 (premaxillary–maxillary–dentary tooth counts), contrary previous suggestions that presence maxillary teeth diagnostic separate species, palmapenis. We also present sensory adaptation, including relatively olfactory bulbs comparison other known stem birds, suggesting olfaction was an aspect ecology. The digitally reconstructed scleral ring suggests strongly diurnal habit, supporting hypothesis early-diverging birds were predominantly active day.

Language: Английский

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Evolutionary insights from an anatomical network analysis of the hyolaryngeal apparatus in extant archosaurs (birds and crocodilians)

The Anatomical Record, Journal Year: 2023, Volume and Issue: 306(7), P. 1631 - 1645

Published: Jan. 3, 2023

Abstract Adaptive radiation of archosaurs, represented by crocodilians, non‐avian dinosaurs, and birds, since the Mesozoic has been studied mainly based on their major skeletal elements (skull, vertebrae, limbs). However, little is known about evolution hyolaryngeal apparatus, which involved with feeding, respiration, vocalization, because poor fossil preservation difficulty in determining musculoskeletal homology apparatus. Network analysis a framework to quantitatively characterize topological organization anatomical structures for comparing structural integration modularity regardless ambiguous homology. Herein, we modeled system hyolarynx six species extant archosaurs its sister‐taxon turtle, conducted network using parameters, modular partition, bone centrality phylogenetic framework. The parameters reveal that ancestral have reduced numbers links acquired complex networks as whole domain strong hyolarynx. Furthermore, partition hyoids are highly evolvable, while larynx constrained less evolvable. archosaur exhibits different evolutionary trends: crocodilians integration, basihyal simplification, ceratobranchial centralization; birds simplicity, weak hyolarynx, laryngeal cricoid centrality, tongue‐module expansion acquisition paraglossal. Four bones (ceratobranchial, basihyal, paraglossal, cricoid) played important roles evolution, records keys understanding two lineages toward birds.

Language: Английский

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Comparative digital reconstruction of Pica pica and Struthio camelus and their cranial suture ontogenies

The Anatomical Record, Journal Year: 2023, Volume and Issue: 307(1), P. 5 - 48

Published: June 20, 2023

Abstract To date, several studies describe post‐hatching ontogenetic variation in birds; however, none of these document and compare the entire skull multiple avian species. Therefore, we studied two bird species with very different ecologies, Pica pica , Struthio camelus using μCT based 3D reconstructions. For each specimen, performed bone‐by‐bone segmentation order to visualize morphological bone during ontogeny estimated average sutural closure skulls identify stages. Although fusion P . occurs more rapidly than that S general sequence follows a similar trend from posterior anterior, but detailed analysis reveals some interspecific patterns. growth persists over longer period adults former are significantly larger, most mature is still less fused Different patterns indicate could be related heterochronic developments. Nevertheless, this hypothesis needs tested broader phylogenetic framework detect evolutionary direction potential transformations.

Language: Английский

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