Comments on the Morphology of Basal Paravian Shoulder Girdle: New Data Based on Unenlagiid Theropods and Paleognath Birds

In 1976 John Ostrom published an enlightening paper about the anatomical transformations in the shoulder girdle and forelimb elements along the origin of birds. Most of his ideas were based on comparing Archaeopteryx lithographica with the extant New World vulture Cathartes aura. Ostrom offered innovative ideas about range of movements and function of wing elements in the basal bird Archaeopteryx. Further, he explored anatomical transformations that may have occurred at early stages of the evolution of flight and established several hypothetical steps toward the acquisition of flapping flight in modern birds. Since then, however, our understanding of paravian diversity and anatomy has increased dramatically. Based on novel information derived from recent experiments, and currently available anatomical evidence of basal paravians, the present paper aims to review some important topics on pectoral girdle anatomy related to flight origins. Further, a brief analysis of pectoral girdle osteology and myology of the extant paleognath Rhea americana is also included with the aim to test whether Ostrom’s ideas still remain valid under this new context, based on available phylogenetic and anatomical frameworks.

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The Early Minoan Occupation of Knossos: A Note on some new Evidence.

Anatolian Studies ◽

10.2307/3642556 ◽

1972 ◽

Vol 22 ◽

pp. 115-128 ◽

Cited By ~ 3

Author(s):

John Evans

Keyword(s):

Bronze Age ◽

Early Years ◽

Major Obstacle ◽

Early Bronze Age ◽

Form And Function ◽

Long Period ◽

Early Stages ◽

And Function ◽

The Hill ◽

New Evidence

Following their discovery of the “Burnt Palace” at Beycesultan in the mid 1950's, Seton Lloyd and James Mellaart drew attention to a number of features of its architecture which seemed to indicate links with the palace architecture of Minoan Crete, and discussed the possible significance of these similarities (Lloyd and Mellaart, 1956 118–123, 1965 61, 62). Whatever this may be in terms of relationships between the two areas in the second millennium B.C., however, it seems clear that they cannot throw any light on the first appearance of palaces in Crete. The problems of the origin and development of the Cretan Bronze Age palaces are complex, and though they have been much discussed since the first excavations in the early years of the century, a major obstacle to progress has always been the lack of precise evidence, or even of any evidence at all, for the early stages of the process. As they stand, most of the palaces are the product of a series of rebuildings and remodellings over a long period, and it is not always clear just what they were like when first erected. Most frustrating of all, however, is the lack of evidence bearing on the question of whether they were preceded, during the Early Bronze Age, by buildings which were in any respect analogous in form and function. It has long been clear that the sites of some of the major Middle and Late Minoan palaces were occupied during the Early Minoan period, but at Phaistos and Knossos at any rate extensive clearing and levelling in preparation for the erection of the Middle Minoan palaces has obliterated practically all traces of the Early Minoan buildings. At Phaistos Branigan has hinted that the fragments of walls found by Pernier (1935, pl. VI) on the highest point of the hill might have belonged to a building of some consequence, possibly similar to the Early Minoan II mansion known as the House on the Hill at Vasiliki (Branigan 1970, p. 41). Branigan thinks that in addition to the rooms mentioned by Pernier, there may be traces of a corridor similar to that in the Vasiliki building. Only the bottom two courses of the walls survive, so that it is difficult to say much about their construction, though it seems to be poorer than that of the walls of some Early Minoan private houses later found by Levi on another part of the site.

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Development of forms and functions of interrogatives in children: a longitudinal study in Tamil

Journal of Child Language ◽

10.1017/s0305000900012551 ◽

1988 ◽

Vol 15 (3) ◽

pp. 533-549 ◽

Cited By ~ 4

Author(s):

R. Vaidyanathan

Keyword(s):

Longitudinal Study ◽

Language Acquisition ◽

Information Seeking ◽

Form And Function ◽

Early Stages ◽

Communicative Functions ◽

Child Interaction ◽

Children First ◽

Case Markers ◽

And Function

ABSTRACTThe development of the forms and functions of interrogatives in parent-child interaction in the early stages of language acquisition is discussed with illustrative examples from data relating to two Tamil-speaking children and their parents. The analysis of the data reveals that children first acquire and use intonation questions followed byenga‘where’,enna‘what’ andyaari‘who’. Yes/no questions using the interrogative marker-aaare acquired in the next stage when the children are able to use verb endings. Similarly question words that take case markers are acquired in the next stage. It is emphasized that interrogatives serve a multiplicity of communicative functions and are not restricted to the information-seeking role. Children, when they begin to use interrogatives, model their usage of them on the adult behaviour patterns to which they have been exposed, both in terms of form and function.

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The dorsomedial visual areas in New World and Old World monkeys: homology and function

European Journal of Neuroscience ◽

10.1046/j.0953-816x.2000.01414.x ◽

2001 ◽

Vol 13 (3) ◽

pp. 421-427 ◽

Cited By ~ 48

Author(s):

Marcello G. P. Rosa ◽

Rowan Tweedale

Keyword(s):

New World ◽

Old World Monkeys ◽

Old World ◽

Visual Areas ◽

And Function

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The oocyte of a new world marsupial,Monodelphis domestica: Structure, formation, and function of the enveloping mucoid layer

Journal of Experimental Zoology ◽

10.1002/jez.1402420316 ◽

1987 ◽

Vol 242 (3) ◽

pp. 363-371 ◽

Cited By ~ 11

Author(s):

David M. Phillips ◽

Barbara H. Fadem

Keyword(s):

Structure Formation ◽

New World ◽

Monodelphis Domestica ◽

And Function

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Investigating the Subcortical Route to the Amygdala Across Species and in Disordered Fear Responses

Journal of Experimental Neuroscience ◽

10.1177/1179069519846445 ◽

2019 ◽

Vol 13 ◽

pp. 117906951984644 ◽

Cited By ~ 2

Author(s):

Jessica McFadyen

Keyword(s):

Visual Information ◽

Sensory Input ◽

Cortical Circuits ◽

Temporal Area ◽

Middle Temporal ◽

Directional Flow ◽

The Past ◽

And Function ◽

Anatomical Evidence

Over the past few decades, evidence has come to light that there is a rapid subcortical shortcut that transmits visual information to the amygdala, effectively bypassing the visual cortex. This pathway purportedly runs from the superior colliculus to the amygdala via the pulvinar, and thus presents a methodological challenge to study noninvasively in the human brain. Here, we present our recent work where we reliably reconstructed the white matter structure and directional flow of neural signal along this pathway in over 600 healthy young adults. Critically, we found structure-function relationships for the pulvinar-amygdala connection, where people with greater fibre density had stronger functional neural coupling and were also better at recognising fearful facial expressions. These results tie together recent anatomical evidence from other visual primates with very recent optogenetic research on rodents demonstrating a functional role of this pathway in producing fear responses. Here, we discuss how this pathway might operate alongside other thalamo-cortical circuits (such as pulvinar to middle temporal area) and how its structure and function may change according to the sensory input it receives. This newly established circuit might play a potentially important role in autism and/or anxiety disorders.

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Structure and function of microbial communities during the early stages of revegetation of barren soils in the vicinity of a Pb/Zn Smelter

Geoderma ◽

10.1016/j.geoderma.2006.04.011 ◽

2006 ◽

Vol 136 (3-4) ◽

pp. 555-565 ◽

Cited By ~ 38

Author(s):

Chongbang Zhang ◽

Linan Huang ◽

Tiangang Luan ◽

Jing Jin ◽

Chongyu Lan

Keyword(s):

Microbial Communities ◽

Structure And Function ◽

Early Stages ◽

And Function

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Competitive Interactions within and between Species in a Guild of Avian Scavengers

The Auk ◽

10.1093/auk/104.2.290 ◽

1987 ◽

Vol 104 (2) ◽

pp. 290-295 ◽

Cited By ~ 105

Author(s):

Michael P. Wallace ◽

Stanley A. Temple

Keyword(s):

Body Mass ◽

New World ◽

Positive Relationship ◽

Competitive Interactions ◽

Cathartes Aura ◽

Dominance Hierarchies ◽

Interspecific Dominance ◽

Northern Peru ◽

Vultur Gryphus ◽

Turkey Vultures

Abstract We observed Andean Condors (Vultur gryphus), King Vultures (Sarcoramphus papa), Black Vultures (Coragyps atratus), Turkey Vultures (Cathartes aura), and Crested Caracaras (Polyborus plancus) interacting at 217 animal carcasses at two sites in northern Peru. At 53 carcasses for which we knew order of arrival, Turkey Vultures usually arrived first, Black Vultures second, and condors third. On the basis of our observations of 8,066 aggressive encounters between birds, we constructed dominance hierarchies by calculating the proportion of encounters won by an individual of one species, sex, or age during encounters with an individual of another species, sex, or age. Within each species there was a positive relationship between a bird's dominance and its age. In condors, males dominated females of the same age. Interspecific dominance was correlated positively with body mass. There are convergent similarities between the organizations of guilds of Old and New World vultures.

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Differentiation of sarcoplasmic reticulum during cardiac myogenesis

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1987.252.1.h22 ◽

1987 ◽

Vol 252 (1) ◽

pp. H22-H31 ◽

Cited By ~ 6

Author(s):

W. Pegg ◽

M. Michalak

Keyword(s):

Sarcoplasmic Reticulum ◽

Developmental Stages ◽

Cardiac Sarcoplasmic Reticulum ◽

Early Stages ◽

Dependent Atpase ◽

Age Related ◽

Cardiac Myogenesis ◽

Dependent Protein ◽

Low Levels ◽

And Function

The composition and function of fetal and mature sheep cardiac sarcoplasmic reticulum membranes were investigated. Phospholamban, a major phosphoprotein in the mature sarcoplasmic reticulum membranes, was present in early stages of cardiac myogenesis. This fetal form of phospholamban was phosphorylated by cAMP-dependent protein kinase but not in the presence of Ca2+ and calmodulin. Ca2+ uptake and Ca2+-dependent ATPase activity were low in fetal sarcoplasmic reticulum compared with the adult controls, although the apparent affinities for Ca2+ were similar. Sarcoplasmic reticulum vesicles isolated at all developmental stages had very low levels of plasma membrane (as determined by Na+-K+-ATPase and Na+-Ca2+ exchanger activities) and mitochondrial contamination. Sarcoplasmic reticulum Ca2+ uptake and Ca2+-dependent ATPase activities were not affected by micromolar concentrations of vanadate, and the accumulated Ca2+ could not be released by the addition of NaCl. The amount of both the 110- and 55-kDa protein bands, identified with specific antibodies as Ca2+-ATPase and calsequestrin, respectively, was low in early stages of cardiac myogenesis. Age-related differences in the Ca2+ transport properties of cardiac sarcoplasmic reticulum and in the amount of the Ca2+-ATPase and calsequestrin may explain alterations in the regulation of intracellular Ca2+ concentrations in the fetal heart. This may contribute to the developmental changes in myocardial function.

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