Comparison of the Pectoral and Pelvic Skeletons and of some other Bones and their Phylogenetic Implications in the Aulorhynchidae and Gasterosteidae (Pisces)

1971 ◽  
Vol 28 (3) ◽  
pp. 427-442 ◽  
Author(s):  
Joseph S. Nelson
Keyword(s):  
Mosaic Pattern ◽  
Primitive Form ◽  
Phylogenetic Implications ◽  
Living Species

Study of the pectoral and pelvic skeletons and some other bones in recognized species of the seven genera comprising the related families Aulorhynchidae (tubesnouts) and Gasterosteidae (sticklebacks) showed that the two families differ in several respects, with no one living species appearing to be intermediate. The genera Aulorhynchus, Aulichthys, Spinachia, Apeltes, and Gasterosteus each have distinctive characteristics not found in any other genus of the two families. Gasterosteus wheatlandi is the only species of the two families that lacks both the posttemporal and the supracleithrum. The interrelations of the genera form a mosaic pattern and there is no acceptable basis in the characters examined for postulating a phylogeny within the Gasterosteidae or for selecting a living species as being a primitive form or the most closely allied to the Aulorhynchidae.

scholarly journals Developmental Evolution of Hypaxial Muscles: Insights From Cyclostomes and Chondrichthyans

2021 ◽  
Vol 9 ◽  
Author(s):  
Rie Kusakabe ◽  
Masako Tanaka ◽  
Shigeru Kuratani
Keyword(s):  
Temporal Order ◽  
Evolutionary Mechanisms ◽  
Evolutionary Pathway ◽  
Primitive Form ◽  
Developmental Evolution ◽  
Skeletal Musculature ◽  
Sequential Addition ◽  
Living Species ◽  
Body Patterns ◽  
And Function

Jawed vertebrates possess two distinct groups of muscles in the trunk (epaxial and hypaxial muscles) primarily defined by the pattern of motor innervation from the spinal cord. Of these, the hypaxial group includes muscles with highly differentiated morphology and function, such as the muscles associated with paired limbs, shoulder girdles and tongue/infrahyoid (hypobranchial) muscles. Here we summarize the latest findings on the evolutionary mechanisms underlying the morphological variety of hypaxial musculature, with special reference to the molecular insights obtained from several living species that diverged early in vertebrate evolution. Lampreys, extant jawless vertebrates, lack many of derived traits characteristic of the gnathostomes, such as jaws, paired fins and epaxial/hypaxial distinction of the trunk skeletal musculatures. However, these animals possess the primitive form of the hypobranchial muscle. Of the gnathostomes, the elasmobranchs exhibit developmental mode of hypaxial muscles that is not identical to that of other gnathostomes in that the muscle primordia relocate as coherent cell aggregates. Comparison of expression of developmental genes, including Lbx genes, has delineated the temporal order of differentiation of various skeletal muscles, such as the hypobranchial, posterior pharyngeal and cucullaris (trapezius) muscles. We have proposed that the sequential addition of distal muscles, associated with expression of duplicated Lbx genes, promoted the elaboration of skeletal musculature. These analyses have revealed the framework of an evolutionary pathway that gave rise to the morphological complexity and diversity of vertebrate body patterns.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Architecture of Radiolitid Rudist (Mollusca) Shell-Wall Structures and its Phylogenetic Implications

1975 ◽  
Vol 33 ◽  
pp. 686-687
Author(s):  
David H. Sturm ◽  
Bob F. Perkins
Keyword(s):  
Phylogenetic Relationships ◽  
Outer Wall ◽  
Shell Microstructure ◽  
Shell Wall ◽  
Wall Structures ◽  
Phylogenetic Implications ◽  
Cellular Wall ◽  
Superfamily Analysis ◽  
Central Texas

Each of the seven families of rudists (Mollusca, Bivalvia, Hippuritacea) is characterized by distinctive shell-wall architectures which reflect phylogenetic relationships within the superfamily. Analysis of the complex, calcareous, cellular wall of the attached valve of the radiolite rudist Eoradiolites davidsoni (Hill) from the Comanche Cretaceous of Central Texas indicates that its wall architecture is an elaboration of the simpler monopleurid rudist wall and supports possible radiolite-monopleurid relationships.Several well-preserved specimens of E. davidsoni were sectioned, polished, etched, and carbon and gold coated for SEM examination. Maximum shell microstructure detail was displayed by etching with a 0.7% HC1 solution from 80 to 100 seconds.The shell of E. davidsoni comprises a large, thick-walled, conical, attached valve (AV) and a small, very thin, operculate, free valve (FV) (Fig. 1a). The AV shell is two-layered with a thin inner wall, in which original structures are usually obliterated by recrystallization, and a thick, cellular, outer wall.

Mosaic Pattern of Lung Attenuation on Thin-Section CT: Review of 31 Cases

1998 ◽  
Vol 39 (1) ◽  
pp. 93
Author(s):  
Young Hi Choi ◽  
Jee Hyun An ◽  
Kye Young Lee ◽  
Young Koo Jee ◽  
Young Seok Lee
Keyword(s):  
Thin Section ◽  
Mosaic Pattern

The Efficacy of Virtual Chromoendoscopy in the Diagnosis of Portal Hypertensive Gastropathy

2016 ◽  
Vol 25 (3) ◽  
pp. 289-293
Author(s):  
Anda Carmen Achim ◽  
Stefan Cristian Vesa ◽  
Eugen Dumitru
Keyword(s):  
Diagnostic Criteria ◽  
White Light ◽  
Narrow Band Imaging ◽  
Endoscopic Examination ◽  
Kappa Statistics ◽  
Portal Hypertensive Gastropathy ◽  
Mosaic Pattern ◽  
White Light Endoscopy ◽  
A New Technique ◽  
Virtual Chromoendoscopy

Background: Diagnosis of portal hypertensive gastropathy (PHG) is based on endoscopic criteria. I-scan technology, a new technique of virtual chromoendoscopy, increases the diagnostic accuracy for lesions in the gastrointestinal tract. Aim: To establish the role of i-scan endoscopy in the diagnosis of PHG. Method: In this prospective study, endoscopic examination was conducted first by using white light and after that i-scan 1 and i-scan 2 technology in a group of 50 consecutive cirrhotic patients. The endoscopic diagnostic criteria for PHG followed the Baveno criteria. The interobserver agreement between white light endoscopy and i-scan endoscopy was determined using Cohen’s kappa statistics. Results: Forty-five of the 50 patients met the diagnostic criteria for PHG when examined by i-scan endoscopy and 39 patients were diagnosed with PHG by white light endoscopy. The strength of agreement between the two methods for the diagnosis of PHG was moderate (k=0.565; 95%CI 0.271-0.859; p<0.001). I-scan 1 classified the mosaic pattern better than classic endoscopy; i-scan 2 described better the red spots. Conclusion: I-scan examination increased the diagnostic sensitivity of PHG. The diagnostic criteria (mosaic pattern and red spots) were easier to observe endoscopically using i-scan than in white light.Abbreviations: FICE: Fuji Intelligent chromoendoscopy; GAVE: gastric antral vascular ectasia; NBI: narrow band imaging; PHG: portal hypertensive gastropathy; PHT: portal hypertension; UGIB: upper gastrointestinal bleeding.

Elementary Affective Sharing

2018 ◽  
Vol 2018 (1) ◽  
pp. 129-150
Author(s):  
Henning Nörnberg
Keyword(s):  
The Other ◽  
Primitive Form ◽  
Phenomenological Tradition ◽  
Current Discussion ◽  
Affective Intentionality ◽  
Elementary Form ◽  
The One ◽  
Central Claim

This paper contributes to the current discussion on collective affective intentionality. Very often, affective sharing is regarded as a special feature ofamore general form of we-intentionality being already in place. In contrast to this view, the paper attempts to explicate a more elementary form of affective sharing that does not simply presuppose other forms of we-intentionality, but amounts to a primitive form of we-intentionality of its own. The account presented here draws on two conceptual tools from the broader phenomenological tradition: prereflective we-intentionality on the one hand and atmospheric perception on the other. The central claim is that some instances of affective we-consciousness mainly emerge on the level of unthematic, pre-reflective orientation within one’s environment. The first part of the paper gives an account of this claim, while second part places the account in the broader discussion on collective affective intentionality.

Affiliations, aggressions and an adoption: Male–male relationships in wild bonobos

2018 ◽  
Author(s):  
Martin Surbeck ◽  
Gottfried Hohmann
Keyword(s):  
Close Relationships ◽  
Group Living ◽  
Mate Competition ◽  
Male Group ◽  
Cooperative Hunting ◽  
Sexual Behaviours ◽  
Study Population ◽  
Living Species ◽  
The Way

The nature of the relationships between males is a characteristic trait of many multi-male group living species with implications for the individuals. In our study population of bonobos, certain male dyads exhibit clear preferences for ranging in the same party and sitting in proximity. These preferences are not reflected in the frequency of aggression towards each other and only to some extent in their affiliative and socio-sexual behaviours. While bonobo males at LuiKotale clearly do not benefit from close relationships in the way chimpanzee males do (cooperative hunting, territorial patrol, mate competition), some relationships might result from close associations between their mothers. In some particular situations, these male relationships can be very important as in the case of an orphan adopted by his older maternal brother. La nature des relations entre mâles est un trait caractéristique de plusieurs groupes qui ont plusieurs mâles, avec des implications au niveau d’individus. Dans notre étude des populations de bonobos, certains dyades mâles montrent une préférence à aller dans le même groupe et s’asseoir proche l’un de l’autre. Cette préférence n’est pas reflétée dans la fréquence d’agression entre eux et est seulement lié, à degrés, à leur comportements socio-sexuels et d’appartenance. Tandis que les mâles bonobos à LuiKotale ne profitent pas de leur fortes relations comme les chimpanzés mâles (chasse coopérative, patrouille territoriale, compétition pour compagnon), ils peuvent aider leur partenaires à supporter le stress de la vie en groupe et peuvent en conséquence contribuer au bien-être des individus. Quelques proches associations entre les mâles peuvent provenir d’associations entre leurs mères. Dans quelques situations particulières, ces relations mâles prouvent leur importance comme dans le cas d’un orphelin adopté par son grand frère maternel.

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