199 research outputs found
The Genyornis egg: response to Miller et al.'s commentary on Grellet-Tinner et al., 2016
No full textGerald Grellet-Tinner, Nigel A. Spooner, Warren D. Handley, Trevor H. Worth
Correction: The evolution of giant flightless birds and novel phylogenetic relationships for extinct fowl (Aves, Galloanseres)
No full textTable 1 was presented incorrectly in the published paper. The corrected table is shown.Fil: Worthy, Trevor Henry. Flinders University; AustraliaFil: Degrange, Federico Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Handley, Warren D.. Flinders University; AustraliaFil: Lee, Mike S. Y.. Flinders University; Australi
Sexual dimorphism in the late Miocene mihirung <i>Dromornis stirtoni</i> (Aves: Dromornithidae) from the Alcoota Local Fauna of central Australia
No full textThe dromornithids were giant flightless birds endemic to Australia from the late Paleogene to the late Pleistocene. Dromornithids are generally considered to be divergent members of the Anseriformes, but they display many convergent features with extant ratites. In this study, we investigate Dromornis stirtoni from the Alcoota Local Fauna, a species for which little is known of its biology. We used traditional methods of comparative morphology, mass estimation, landmark-based morphometrics, and histological investigations to determine the presence of medullary bone, to assess the possible presence, form, and extent of sexual dimorphism in D. stirtoni. Two morphological groups were identified for each main leg element, differing primarily in relative robustness. Core samples from femora and tibiotarsi shafts revealed medullary bone in the less robust morph, indicating that these were females. Mass, as estimated by algorithms applied to our preferred measurement of least-shaft circumference of tibiotarsi, was significantly different between males (mean = 528 kg) and females (mean = 451 kg). Therefore, male D. stirtoni were more robust but not much taller than the females and challenge the elephant bird, Aepyornis maximus, for the title of the most massive bird to have existed. Sexual dimorphism in this largest of all dromornithids, therefore, was like that of extant Anseriformes. We infer long-term monogamy, mutual display, shared parental care, female incubation, and aggressive defense of nests in these birds. The techniques of geometric morphometrics applied in this study maximize the use of fragmentary material, helping to overcome the common paleontological challenge of limited sample sizes. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP
Citation for this article: Handley, W. D., A. Chinsamy, A. M. Yates, and T. H. Worthy. 2016. Sexual dimorphism in the late Miocene mihirung Dromornis stirtoni (Aves: Dromornithidae) from the Alcoota Local Fauna of central Australia. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1180298.</p
A MODIFIED CASE STUDY EXAMINING THE EFFECTS OF SPECIFIC SCHOOL GRADE-LEVEL ORGANIZATIONAL MODELS ON NINTH-GRADE LEARNERS
No full textThis doctoral dissertation represents a qualitative study employing a modified case study research design that is intended to assess the perspectives of school practitioners (i.e., principals, guidance counselors, and teachers) who work with ninth graders relevant to their perceptions of the developmental needs of those students, how their respective schools address those needs, and the effects their schools’ grade-level organizational plans may have on grade nine. This study employs semi-structured interviews, document reviews, and direct observations for data collection. Two case sites were selected for this dissertation—one populated by students in grades nine through twelve (9-12) and another with pupils in grades seven through nine (7-9). Both sites were selected purposefully on the basis of their grade-level configurations, their contemporary and historical relevance to ninth-grade-level education, and their proximity to the principal researcher. Sample groups at each school included 10 practitioners who worked directly with ninth graders within a multitude of professional realms, particularly administration, counseling, and teaching. Upon site selection, building principals were recruited for participation in this study; henceforth, those subjects selected nine other participants of faculty rank based on their professional positions and affiliations with students at the ninth-grade level.
The data seems to indicate that practitioners at the grades 9-12 high school perceive ninth graders differently from that of their counterparts at the grades 7-9 junior high school. The high-school subjects generally describe ninth graders as being immature, whereas participants at the junior high school perceive them the opposite of that. It also appears that participants at the grades 9-12 site lack consensus on the attributes of ninth-grade developmental needs with some questioning the appropriateness and/or legitimacy of four-year high schools for educating students at that grade level, while others ardently support that construct. Conversely, practitioners at the grades 7-9 junior high school seem to be unified in their perspectives on ninth-grade-level development—contending that ninth graders are better educated in junior high schools versus senior high schools and that their school is developmentally appropriate and more suitable for ninth-grade learners
A CASE STUDY IN CONSERVATION PALEOBIOLOGY: THE MOLLUSCAN COMMUNITY OF THE COLORADO RIVER ESTUARY
No full textThe Colorado River no longer reaches the Gulf of California in most years due to numerous upstream dams and associated water diversions for consumptive use. The downstream estuary in Mexico has undergone habitat change as a consequence; however, a paucity of pre-impact data has made it challenging to assess the full scope of change. Fortunately, along the shoreline in the estuary there are accumulations of clam and snail shells that predate dam construction and can provide an invaluable perspective on past community dynamics in the molluscan community. Shell accumulations in the estuary were sampled during 2013 and 2014 at three sites along the north-south salinity gradient that existed prior to upstream water diversions. The living community was sampled during 2014 at the northern-most of these sites, which corresponds to the most estuarine environment from the past. In the following five chapters, a variety of analytical methods are applied to different subsets of the samples to assess change at multiple levels of the ecological hierarchy. Major results from these chapters include: (1) identification of a new predatory snail species in the estuary; (2) evidence suggesting decreases in predator populations in the estuary due to reduction in prey availability; (3) documentation of population decreases in species with preferences for low-salinity conditions and population increases for species with preferences for high-salinity conditions; (4) increases in community evenness and richness in the post-impact community; (5) evidence suggesting a shift in the processes controlling community assembly from environmental preference and dispersal capacity to competition-colonization tradeoff; and, (6) a reduction in carbon emissions from the estuary due to decreases in the clam population. Restoration efforts are ongoing in the Colorado River estuary under multiple binational agreements between the United States and Mexico. The results presented here represent baseline data that can be used to evaluate the success of those efforts and to inform the best strategies for restoration success. Counterintuitive as it may seem, restoration success likely means a reduction in the number of species living in the estuary and an increase in estuarine carbon emissions
Endocranial Anatomy of the Giant Extinct Australian Mihirung Birds (Aves, Dromornithidae)
No full textDromornithids are an extinct group of large flightless birds from the Cenozoic of Australia. Their record extends from the Eocene to the late Pleistocene. Four genera and eight species are currently recognised, with diversity highest in the Miocene. Dromornithids were once considered ratites, but since the discovery of cranial elements, phylogenetic analyses have placed them near the base of the anseriforms or, most recently, resolved them as stem galliforms. In this study, we use morphometric methods to comprehensively describe dromornithid endocranial morphology for the first time, comparing Ilbandornis woodburnei and three species of Dromornis to one another and to four species of extant basal galloanseres. We reveal that major endocranial reconfiguration was associated with cranial foreshortening in a temporal series along the Dromornis lineage. Five key differences are evident between the brain morphology of Ilbandornis and Dromornis, relating to the medial wulst, the ventral eminence of the caudoventral telencephalon, and morphology of the metencephalon (cerebellum + pons). Additionally, dromornithid brains display distinctive dorsal (rostral position of the wulst), and ventral morphology (form of the maxillomandibular [V2+V3], glossopharyngeal [IX], and vagus [X] cranial nerves), supporting hypotheses that dromornithids are more closely related to basal galliforms than anseriforms. Functional interpretations suggest that dromornithids were specialised herbivores that likely possessed well-developed stereoscopic depth perception, were diurnal and targeted a soft browse trophic niche
Review of Reclaimed
No full textWhen Middlemarch was being issued in Eight Parts from December 1871 until December 1872, there was a strong readership interest in the fact that Dorothea and Lydgate had made, in each instance, a wrong choice of marriage mate. It went farther than this, some readers even expressing the view that Dorothea and Lydgate would have been ideally suited. With Daniel Deronda, which was also issued in parts from February to September 1876, readership sympathy was also involved. There was much dissatisfaction in Daniel\u27s forsaking of Gwendolen at the end (\u27I said I should be forsaken: says Gwendolen in her anguish) and going off to marry Mirah, embrace Judaism, and perhaps come back \u27some time: Indeed, so strong was this sense of frustration in one reader, that het she wrote a sequel to Daniel Deronda. It was published in 1878. The title-page has Gwendolen: A Sequel to George Eliot\u27s Daniel Deronda. library Edition. Ira Bradley and Company. 1878, but the first page of the novel has the word RECLAIMED at the top, followed by the first chapter, the latter headed by a motto in the George Eliot manner. The binding of the volume, incidentally, is exactly the same as that of the two-volume American edition of Daniel Deronda published by Harper and Brothers in 1876. I had heard about the sequel vaguely some years ago, and was excited when I found this copy in Coventry Central library during my visit last October.
The notorious Newby did not issue his sequel Adam Bede Inr, either because of the threat of legal proceedings or because it didn\u27t get written. Unhappily, Reclaimed got written and my excitement on opening it quickly cooled. The opening is sensational enough, the author\u27s wish-fulfilment being quickly translated into fictional fact. Daniel is initially happy with Mirah, but abandons his Jewish views \u27consequent upon his observing Jewish life in reality: We are told that \u27the East was growing irksome to him\u27. He goes on a journey (the journeys in this novel are always fraught with crisis and discovery), having left Mirah in Cairo. He is summoned back: Mirah\u27s child dies, followed shortly afterwards by Mirah herself, at the end of the first chapter. Daniel, whose memory extends back to his first meeting with Mirah on the Thames at Richmond, recites the words he was then singing. The author\u27s translation of these words is given in a footnote, just like the original footnote in Daniel Deronda. An eerie feeling comes over the reader (or perhaps I should say this reader) at this stage. Imagine all the sequels that could have been written after certain novels, and I don\u27t mean sequels like Jean Rhys\u27s to lane Eyre, for Wide Sargasso Sea has its own fasdnations and a particularised artistic independence. But think of a sequel to Tess of the D\u27Urbervilles. What kind of domestic life did Angel Gare and Liza Lu have? Was she always throwing his love for Tess in his face? Or suppose there was a sequel to Women in Love. Who else did Gudrun help to destroy? Is it possible that she might have an affair with Birkin? I remember in the 1960\u27s a romantic novelist called, I think, Patricia Robins, producing a sequel to the most discussed novel of that decade. She called it Lady Chatterley\u27s DauKhter. It was salacious and almost permissive. Reclaimed is dull and Gothic. Gwendolen (unrecognisably dull, conscience-stricken, unvibrant despite the author\u27s use of the word \u27elasticity\u27) is brooding
The policy of the Church Missionary Society concerning the development of self-governing indigenous churches 1900-1942
No full textThis study examines the leadership and administration of the Church Missionary Society (CMS) between 1900 and 1942. It concentrates on the particular policy issue of' self-governing, indigenous Churches', building on the work done by Peter Williams on this policy in the CMS during the 19th century. It begins with an analysis of the way the CMS worked as an organisation in Britain throughout the period. This includes the contribution to the leadership of the CMS from
both supporters and staff, along with a discussion of the change in the role of women with the society. The main voices heard in this study are those of the leadership of the CMS in Britain, particularly the full time 'Secretaries'. The tension between being an 'evangelical' society and being an 'Anglican' society runs through the whole period, but was particularly marked in 1922 when a split occurred within the CMS.
The policy at the start of the period is examined through a detailed discussion of a
Memorandum on 'native' Churches produced in 1901, which committed the CMS to work exclusively to produce Churches that would be part of the Anglican Communion. A study of the way the CMS Missions around the world were governed, and how they related to the Churches they had helped found, reveals that until 1922 very little progress was made in producing Churches that were not governed by the CMS. A study of another Memorandum in 1909 shows that the Secretaries at this time were trying to keep a significant degree of control over CMS, rather than being proactive in developing the leadership structures for the new Churches. In the 1920s and 1930s much more rapid progress was made in India and China, but not in Africa. This caused significant concern within the CMS leadership in Britain, that in the process' evangelical principles' were not being safeguarded. From 1926-1942 the CMS was led by W.W. Cash. His background, theology and attitudes are examined in some detail. During the whole period, very little progress was made in producing indigenous bishops, in any of the areas in which CMS worked. The CMS had some influence over the appointment of bishops in its Mission areas. The actual degree of influence is examined. The CMS only started encouraging the appointment ofloca1 people as diocesan bishops in the late 1930s, in India and China, and always opposed their appointment in Africa. The reasons behind this policy, and how it changed over time, are also explored. By the end of the period some significant steps had been made, towards a 'self-governing, indigenous Church', particularly in India, but the CMS had still not realised its goal
Experimental and numerical investigation of leading edge Krueger flaps at low Reynolds numbers
No full textRecent publications examining the flight of Eagles have shown that leading edge feather deflections occur on the lower surface of the wings in free flight to create a leading edge flap analogous to a Krueger flap system.
Such passive high lift devices may be adaptable to the lifting surfaces of unmanned air vehicles (UAVs). This work is aimed to an application of a passive leading edge Krueger device which will deploy during the landing and takeoff stages of a UAV flight. Cont/d
Osteology Supports a Stem-Galliform Affinity for the Giant Extinct Flightless Bird Sylviornis neocaledoniae (Sylviornithidae, Galloanseres)
No full textThis is an open
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.The giant flightless bird Sylviornis neocaledoniae (Aves: Sylviornithidae) existed on La
Grande Terre and Ile des Pins, New Caledonia, until the late Holocene when it went extinct
shortly after human arrival on these islands. The species was generally considered to be a
megapode (Megapodiidae) until the family Sylviornithidae was erected for it in 2005 to
reflect multiple cranial autapomorphies. However, despite thousands of bones having been
reported for this unique and enigmatic taxon, the postcranial anatomy has remained largely
unknown.We rectify this deficiency and describe the postcranial skeleton of S. neocaledoniae
based on ~600 fossils and use data from this and its cranial anatomy to make a comprehensive
assessment of its phylogenetic affinities. Sylviornis neocaledoniae is found to
be a stem galliform, distant from megapodiids, and the sister taxon to the extinct flightless
Megavitiornis altirostris from Fiji, which we transfer to the family Sylviornithidae. These two
species form the sister group to extant crown-group galliforms. Several other fossil galloanseres
also included in the phylogenetic analysis reveal novel hypotheses of their relationships
as follows: Dromornis planei (Dromornithidae) is recovered as a stem galliform rather
than a stem anseriform; Presbyornis pervetus (Presbyornithidae) is the sister group to
Anseranatidae, not to Anatidae; Vegavis iaai is a crown anseriform but remains unresolved
relative to Presbyornis pervetus, Anseranatidae and Anatidae. Sylviornis neocaledoniae
was reconstructed herein to be 0.8 m tall in a resting stance and weigh 27–34 kg. The postcranial
anatomy of S. neocaledoniae shows no indication of the specialised adaptation to
digging seen in megapodiids, with for example, its ungual morphology differing little from
that of chicken Gallus gallus. These observations and its phylogenetic placement as stem
galliforms makes it improbable that this species employed ectothermic incubation or was a
mound-builder. Sylviornis neocaledoniae can therefore be excluded as the constructor of
tumuli in New Caledonia
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