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Article
Open AccessEvolutionary trends in the elasmobranch neurocranium
The neurocranium (braincase) is one of the defining vertebrate characters. Housing the brain and other key sensory organs, articulating with the jaws and contributing to the shape of the anteriormost portion o...
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Article
Open AccessFossil evidence for a pharyngeal origin of the vertebrate pectoral girdle
The origin of vertebrate paired appendages is one of the most investigated and debated examples of evolutionary novelty1–7. Paired appendages are widely considered as key innovations that enabled new opportunitie...
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Article
Open AccessShark mandible evolution reveals patterns of trophic and habitat-mediated diversification
Environmental controls of species diversity represent a central research focus in evolutionary biology. In the marine realm, sharks are widely distributed, occupying mainly higher trophic levels and varied die...
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Article
Endochondral bone in an Early Devonian ‘placoderm’ from Mongolia
Endochondral bone is the main internal skeletal tissue of nearly all osteichthyans—the group comprising more than 60,000 living species of bony fishes and tetrapods. Chondrichthyans (sharks and their kin) are ...
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Article
Open AccessThe pharynx of the stem-chondrichthyan Ptomacanthus and the early evolution of the gnathostome gill skeleton
The gill apparatus of gnathostomes (jawed vertebrates) is fundamental to feeding and ventilation and a focal point of classic hypotheses on the origin of jaws and paired appendages. The gill skeletons of chond...
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Open AccessX-ray computed tomography library of shark anatomy and lower jaw surface models
The cranial diversity of sharks reflects disparate biomechanical adaptations to feeding. In order to be able to investigate and better understand the ecomorphology of extant shark feeding systems, we created a...
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Article
Osteichthyan-like cranial conditions in an Early Devonian stem gnathostome
A new analysis of a 415-million-year-old fossil fish head originally described as from an early osteichthyan (bony fish) puts it instead as the sister group of the gnathosomes (jawed vertebrates), and suggests...
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Article
The origin and early phylogenetic history of jawed vertebrates
Fossils of early gnathostomes (or jawed vertebrates) have been the focus of study for nearly two centuries. They yield key clues about the evolutionary assembly of the group's common body plan, as well the div...
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Article
A jaw-drop** fossil fish
The ancestors of modern jawed vertebrates are commonly portrayed as fishes with a shark-like appearance. But a stunning fossil discovery from China puts a new face on the original jawed vertebrate. See Article ...
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Initial radiation of jaws demonstrated stability despite faunal and environmental change
The first jawed vertebrates, or gnathostomes, were vastly outnumbered by their jaw-less relatives. Today, more than 99% of vertebrates have jaws. It is therefore tempting to conclude that the evolution of jaws...
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Article
The braincase and jaws of a Devonian ‘acanthodian’ and modern gnathostome origins
Acanthodians are long-extinct fossil fish that stand close to the divergence of cartilaginous and bony fishes. Their morphology has the potential to reveal much about the early evolution of jawed vertebrates. ...
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Article
Tetrapod-like middle ear architecture in a Devonian fish
Detailed study of Panderichthys, a lobe-finned fish closely related to the first amphibians, suggests that the early stages in the evolution of the vertebrate middle ear were related to breathing, rather than det...