The Relations of the Anterior Visceral Arches to the Chondrocranium

Gregory, William K.

doi:10.2307/1535500

Cited by 47 publications

(68 citation statements)

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“…Although the jaw suspension mechanism of H. francisci is classified as hyostylic (Gregory, 1904;Wilga, 2002), this analysis indicates that it is functionally amphistylic. Heterodontus francisci exhibits considerable upper jaw kinesis (reduces maximum gape by 39%), similar to other hyostylic carcharhiniform sharks (Edmonds et al, 2001;Wilga et al, 2001).…”

Section: (A) Bite Forces (N) Of Various Vertebrates Plotted Against Mmentioning

confidence: 82%

“…However, a number of variants on this arrangement exist, primarily in the superorder Squalea (Gregory, 1904;Shirai, 1996;Wilga, 2002). The hexanchiform sharks possess an orbitostylic jaw suspension in which the upper jaw articulates with the ethmoidal, orbital and postorbital regions of the chondrocranium, and the hyomandibula contributes little support to the jaws (Fig.·1B).…”

mentioning

confidence: 99%

“…The hexanchiform sharks possess an orbitostylic jaw suspension in which the upper jaw articulates with the ethmoidal, orbital and postorbital regions of the chondrocranium, and the hyomandibula contributes little support to the jaws (Fig.·1B). Conversely, the only suspensorial element in the batoids is the hyomandibula (euhyostyly; Fig.·1C; Gregory, 1904;Maisey, 1980;Wilga, 2002). These highly divergent morphologies constitute independent mechanical systems, perhaps with comparably divergent cranial loading regimes occurring during feeding.…”

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confidence: 99%

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Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

Huber

Eason

Hueter

et al. 2005

Journal of Experimental Biology

144

182

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Three-dimensional static equilibrium analysis of the forces generated by the jaw musculature of the horn shark Heterodontus francisci was used to theoretically estimate the maximum force distributions and loadings on its jaws and suspensorium during biting. Theoretical maximum bite force was then compared with bite forces measured (1) voluntarily in situ, (2) in restrained animals and (3) during electrical stimulation of the jaw adductor musculature of anesthetized sharks. Maximum theoretical bite force ranged from 128·N at the anteriormost cuspidate teeth to 338·N at the posteriormost molariform teeth. The hyomandibula, which connects the posterior margin of the jaws to the base of the chondrocranium, is loaded in tension during biting. Conversely, the ethmoidal articulation between the palatal region of the upper jaw and the chondrocranium is loaded in compression, even during upper jaw protrusion, because H. francisci's upper jaw does not disarticulate from the chondrocranium during prey capture. Maximum in situ bite force averaged 95·N for free-swimming H. francisci, with a maximum of 133·N. Time to maximum force averaged 322·ms and was significantly longer than time away from maximum force (212·ms). Bite force measurements from restrained individuals (187·N) were significantly greater than those from free-swimming individuals (95·N) but were equivalent to those from both theoretical (128·N) and electrically stimulated measurements (132·N). The mean mass-specific bite of H. francisci was greater than that of many other vertebrates and second highest of the cartilaginous fishes that have been studied. Measuring bite force on restrained sharks appears to be the best indicator of maximum bite force. The large bite forces and robust molariform dentition of H. francisci correspond to its consumption of hard prey.

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Section: (A) Bite Forces (N) Of Various Vertebrates Plotted Against Mmentioning

confidence: 82%

mentioning

confidence: 99%

mentioning

confidence: 99%

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Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

Huber

Eason

Hueter

et al. 2005

Journal of Experimental Biology

144

182

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“…First, regardless of the particulars of adult (or reproductive) phenotype, a basic seminal structural bauplan (unitary plan) is initially ontogenetically followed (see Reichert, 1837;Parker, 1866Parker, , 1869Parker, , 1871Parker, , 1873Parker, , 1876Parker, -79, 1881Parker, -83, 1885aHuxley, 1869;Gegenbaur, 1888;Wiedersheim and Parker, 1897;Gaupp, 1898Gaupp, , 1899Howes and Swinnerton, 1901;Gregory, 1904Gregory, , 1913Gregory, , 1933Reynolds, 1913;Kindred, 1921;Wilder, 1923;Kingsley, 1925;Kingsbury, 1926;de Beer, 1937;Paterson, 1939;Nelsen, 1953;Romer, 1956Romer, , 1966Jollie, 1957Jollie, , 1962Jollie, , 1977Goodrich, 1958;Romanoff, 1960;Young, 1962;Schmalhausen, 1968;Allin, 1975;Presley and Steel, 1976;Crompton and Parker, 1978;Barghusen and Hopson, 1979;Bellairs and Kamal, 1981;Moore, 1981;Kuhn and Zeller, 1987;…”

Section: Introductionmentioning

confidence: 99%

21^st Century neontology and the comparative development of the vertebrate skull

Depew

Simpson

2006

Developmental Dynamics

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Classic neontology (comparative embryology and anatomy), through the application of the concept of homology, has demonstrated that the development of the gnathostome (jawed vertebrate) skull is characterized both by a fidelity to the gnathostome bauplan and the exquisite elaboration of final structural design. Just as homology is an old concept amended for modern purposes, so are many of the questions regarding the development of the skull. With due deference to Geoffroy-St. Hilaire, Cuvier, Owen, Lankester et al., we are still asking: How are bauplan fidelity and elaboration of design maintained, coordinated, and modified to generate the amazing diversity seen in cranial morphologies? What establishes and maintains pattern in the skull? Are there universal developmental mechanisms underlying gnathostome autapomorphic structural traits? Can we detect and identify the etiologies of heterotopic (change in the topology of a developmental event), heterochronic (change in the timing of a developmental event), and heterofacient (change in the active capacetence, or the elaboration of capacity, of a developmental event) changes in craniofacial development within and between taxa? To address whether jaws are all made in a like manner (and if not, then how not), one needs a starting point for the sake of comparison. To this end, we present here a "hinge and caps" model that places the articulation, and subsequently the polarity and modularity, of the upper and lower jaws in the context of cranial neural crest competence to respond to positionally located epithelial signals. This model expands on an evolving model of polarity within the mandibular arch and seeks to explain a developmental patterning system that apparently keeps gnathostome jaws in functional registration yet tractable to potential changes in functional demands over time. It relies upon a system for the establishment of positional information where pattern and placement of the "hinge" is driven by factors common to the junction of the maxillary and mandibular branches of the first arch and of the "caps" by the signals emanating from the distal-most first arch midline and the lamboidal junction (where the maxillary branch meets the frontonasal processes). In this particular model, the functional registration of jaws is achieved by the integration of "hinge" and "caps" signaling, with the "caps" sharing at some critical level a developmental history that potentiates their own coordination. We examine the evidential foundation for this model in mice, examine the robustness with which it can be applied to other taxa, and examine potential proximate sources of the signaling centers. Lastly, as developmental biologists have long held that the anterior-most mesendoderm (anterior archenteron roof or prechordal plate) is in some way integral to the normal formation of the head, including the cranial skeletal midlines, we review evidence that the seminal patterning influences on the early anterior ectoderm extend well beyond the neural plate and are just as importan...

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“…O palatoquadrado e a cartilagem mandibular fazem parte do chamado arco maxilar, enquanto as cartilagens hiomandibulares, as cartilagens ceratohiais, o basihial e os faringohiaisobservados em quimeras (Dean, 1906; Didier, 1996;Mickoleit, 2004) -formam o arco hioide (Moss, 1977;Compagno, 1999; Compagno, 2003 (Wilga, 2002). A projeção permite aos elasmobrânquios explorarem vantagens mecânicas durante a captura da presa como a melhoria na manipulação da presa, o aumento da precisão durante a captura de presas bentônicas através da sucção ou da investida (Moss, 1977) e o impacto simultâneo dos dentes superiores e inferiores com a presa (Frazzetta & Prange, 1987).Dados sugerem que a projeção do palatoquadrado varie tanto intraespecificamente como interespecificamente (Liem & Summers, 1999 (Gregory, 1904;Didier, 1995;Wilga, 2002). A condição orbitostílica, proposta por Maisey (1980), está reservada a alguns representantes do táxon Squalea que possuem o processo orbital articulado a parede orbital.…”

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Miologia comparada dos arcos maxilar e hioide em Chondrichthyes e sua relevância nas hipóteses filogenéticas das espécies viventes

Soares¹

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Muito do material coletado foi proveniente de coletas organizadas pelo Prof. Dr.Fernando Marques. Agradeço muito a ele e seus alunos (Mauro Cardoso Jr., VerônicaMantovani Bueno e Natália Luchetti) pela ajuda e interesse em Chondrichthyes durante esses anos. Também agradeço seu ex-aluno, e hoje professor na UFPA, Dr. Marcus Domingues pelas conversas que tivemos e por abrir portas na UNIFESP -Diadema para que eu pudesse mostrar um pouco do meu trabalho.Ao longo desses quatros anos, fiz grandes amigos no departamento. Chondrichthyes: Abordagens filogenéticasA vasta radiação dos Chondrichthyes tem cerca de 3000 espécies extintas conhecidas (Compagno, 1999) e certamente é um dos grupos com maior sucesso em termos de resistência histórica, sobrevivendo às extinções em massa que ocorreram nos últimos 400 milhões de anos (Grogan & Lund, 2004) e ocupando ambientes marinhos e de água doce (Compagno, 1990). Registros fósseis de espécies do grupo são conhecidos a partir do final do Ordoviciano (450 milhões de anos atrás) através de dentículos dérmicos (Samson et al., 1996). Desde Bonaparte (1832), a classe é dividida em duas subclasses (na ocasião, o autor usou os termos Selacha e Holocephala) e atualmente, cerca de 1100 espécies de tubarões e raias formam os Elasmobranchii (Ebert & Compagno, 2007) e 33 espécies de quimeras estão unidas dentro de Holocephali (Didier, 1995).Opiniões contrárias ao monofiletismo do grupo são apresentadas por alguns autores. Jarvik (1960) acreditava no surgimento dos Chondrichthyes a partir de diferentes linhagens de placodermes. Stensiö (1925Stensiö ( , 1963Stensiö ( , 1969Stensiö ( e 1971 classificou apenas os Holocephali como Placoderma. Patterson (1965, p. 212) segue a mesma ideia e, apesar das evidências de afinidade genética entre quimeras e elasmobrânquios, afirmaque Holocephali e Arthrodira compartilhem mais características. Hipóteses sobre a origem das raias a partir de Placodermes são apresentadas por Holmgren (1942), onde as raias são relacionadas aos Petalichthydae, e Jarvik (1980), que argumenta que as raias derivaram de formas com um exoesqueleto similar aos Rhenanidae ou de uma linhagem de Arthrodira. Jarvik (1977 & 1980) ainda insistiu na proximidade entre Acanthodi e tubarões.2 Considera-se, atualmente, que monofiletismo da classe seja sustentado, essencialmente, pela calcificação prismática do esqueleto (Schaeffer & Willians, 1977;Schaeffer, 1981;Maisey, 1984a;Maisey, 1986), pela presença de um órgão copulador, o clásper pélvico, nos machos (Schaeffer & Willians, 1977;Maisey, 1986) e substituição periódica de fileiras dentárias (Maisey, 1986).. Porém, esses caracteres são discutidos por alguns autores. Pradel et al. (2009) Em contrapartida à classificação proposta através do estudo morfológico (Shirai, 1992b;, Douady et al. (2003) et al., 2003). A miologia como ferramenta para interpretações filogenéticasApesar de ser uma classe com pequeno número de espécies, quando comparada, por exemplo, aos peixes ósseos, os Chondrichthyes são muito diversificados em relação ao compo...

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The Relations of the Anterior Visceral Arches to the Chondrocranium

Cited by 47 publications

References 0 publications

Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

21^st Century neontology and the comparative development of the vertebrate skull

Miologia comparada dos arcos maxilar e hioide em Chondrichthyes e sua relevância nas hipóteses filogenéticas das espécies viventes

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The Relations of the Anterior Visceral Arches to the Chondrocranium

Cited by 47 publications

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Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

21st Century neontology and the comparative development of the vertebrate skull

Miologia comparada dos arcos maxilar e hioide em Chondrichthyes e sua relevância nas hipóteses filogenéticas das espécies viventes

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21^st Century neontology and the comparative development of the vertebrate skull