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1.
Abstract

The aim of this note is to bring to wider attention a painting, entitled The Temptation of Saint Anthony, by Roelandt Savery sold at Sotheby’s London on 7th December 2016. This work of c.1611–1613 includes a depiction of the head of a dodo (Raphus cucullatus), here argued to be probably his earliest depiction of the dodo and apparently one based upon a preserved specimen. The date of the other putatively early Savery dodo (Gemäldegalerie Alte Meister, Berlin, Inv. No. 717a), cited as 1611 by some, is also discussed, and shown to be almost certainly a late work. In addition, another depiction of the dodo by Savery, in the National Museum of Warsaw, also previously unnoticed in the ornithological literature, is documented.  相似文献   
2.
《Ostrich》2013,84(3):233-242
Meyer's Parrot Poicephalus meyeri is the only cavity-nesting bird species that breeds during winter in the Okavango Delta. This is facilitated by exclusive access to arthropod larvae incubating inside and feeding on fruits and pods in their diet. To minimise predation risk and overcome low overnight temperatures they have specialised, non-random nest cavity preferences that restrict them to 4.5% of the available nest cavities in the study area. Here we evaluated the nest niche of Meyer's Parrot by studying the nest tree preferences and ecological context of all nest cavities to determine factors that may restrict breeding success in disturbed or altered habitat. Although specific nest tree preferences were significantly different between host tree species, Meyer's Parrot preferred trees greater than 14 m in height that were in relatively poor condition (e.g. portion of the canopy dead). A comparison of nest tree characteristics (n = 75) and the availability of these tree specifications in a representative sample of the different habitat types (n = 1 129) within the sample area indicated that Meyer's Parrot are dependent on riverine forest, Acacia-Combretum marginal woodland and dry mopane woodland for nesting opportunities. Disturbance to hardwood trees by African elephants Loxodonta africana and fungal attack (e.g. Coriolus versicolor) are likely important dynamics in supporting healthy Meyer's Parrot populations and cavity-nesting bird communities.  相似文献   
3.
The solitaire (Columbidae; Pezophaps solitaria) of Rodrigues was an extinct giant flightless pigeon and the sister taxon to the dodo (Columbidae; Raphus cucullatus) from neighbouring Mauritius. The appearance and behaviour of the solitaire was recorded in detail by two observers before it became extinct in the mid 1700s. They described a prominent wing structure termed the ‘musket ball’ (carpal knob), which was used as a weapon and to produce an audible signal by either sex in territorial combat. Our study of subfossil solitaire bones from cave localities shows that the carpal knob formed after skeletal maturity, and reached its greatest size in adult males. We describe the morphology of the carpal knob, including its histology in thin section. It is an outgrowth of the processus extensorius of the carpometacarpus, but differs morphologically from homologous structures in other bird taxa, and thus is unique in Aves. We also compare the pectoral and wing osteology of the solitaire with that of the dodo, which had a similar morphology, but lacked any bony outgrowths on the wing. Furthermore, we suggest some biological and environmental factors leading to the evolution of this remarkable and unique carpal weapon. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 32–44.  相似文献   
4.
5.
The fate of the proximal centriole in passeridan birds is an area of controversy and relative lack of knowledge in avian spermatogenesis and spermatology. This study examines, for the first time, spatiotemporal changes in the centriolar complex in various phases of spermiogenesis in a passerine bird, the Masked weaver (Ploceus velatus). It also describes the configuration of the centriolar complex and the relationship between it and the granular body in both intra- and extra-testicular spermatozoa. It is shown that the proximal centriole is retained and attaches, at its free end, to the granular body of spermatids in every step of spermiogenesis, as well as in mature intra-testicular and post-testicular spermatozoa, including those in the lumen of the seminal glomus. As the centriolar complex, along with its attached granular body, approaches the nucleus in the early spermatid, the proximal centriole articulates with the distal centriole at an acute angle of about 45°, and thereafter, both centrioles, still maintaining this conformation, implant, by means of their articulating proximal ends, at the implantation fossa of the nucleus. In the mature spermatid and spermatozoon, the granular body winds itself helically around the centriolar complex in the neck/midpiece region of the cell, and, thus, becomes the granular helix. The significance of this observation must await future studies, including possible phylogenetic re-evaluation and classification of birds.  相似文献   
6.
In contrast to African Village Weavers (Ploceus cucullatus)that are parasitized by Diederik Cuckoos (Chrysococcyx caprius),introduced weavers on Hispaniola existed without parasitismfor at least 2 centuries until the arrival of the Shiny Cowbird(Molothrus bonariensis) in the 1970s. Cruz and Wiley (1989)found that Hispaniolan weavers had a lower rejection rate offoreign eggs than African populations. Subsequently, Robertand Sorci (1999) and Lahti (2005, 2006) found that acceptanceof dissimilar eggs is not characteristic of the species throughoutits Hispaniolan range. In 1999–2002, we studied egg rejectionin Hispaniolan weavers on a broad regional scale. Rejectionincreased as experimental eggs became increasingly differentfrom the host eggs. Rejection rates for mimetic eggs, differentcolor eggs, different-spotting eggs, and cowbird eggs was 23.2%,33.3%, 61.5%, and 85.3%, respectively, with higher rejectionof cowbird eggs in areas where cowbirds were observed. Althoughrejection is likely to have a genetic component, the differencescould be due to phenotypic plasticity. Plasticity in egg rejectionmay be expected, given the potential cost of rejection and thespatiotemporal distribution of cowbirds. Thus, egg rejectionhas not necessarily decreased in Hispaniolan weavers, but itmay act in a plastic manner, increasing where cowbirds are present.  相似文献   
7.
The Tradescant or Oxford Dodo has played an important role in exhibition and education throughout its 360-year history, and has been the subject of scientific research reflecting changing interests and techniques over this time. Due to confusion over its relationships, its placement in the classification systems continually changed, until the dissection in 1847 of the head and foot confirmed its columbid (pigeons and doves) affinities. Here, we describe the dissection of the head and foot and the Tradescant Dodo’s display history, from the late nineteenth century until the present day, and also its use in education. We discuss the importance of the Tradescant Dodo to Lewis Carroll, whose ‘Alice’s Adventures in Wonderland’ made the dodo aware to a worldwide audience. We further provide an overview of recent work including electron microscopic study of feathers, mDNA analysis, cytological investigation of the skin and measuring of the brain capacity, all of which have added to our knowledge of the evolution and ecology of this most extraordinary of birds. Research is ongoing; the Tradescant Dodo is presently subject to CT scanning and functional analysis. This is the second part of a two-part paper.  相似文献   
8.
The Dodo Raphus cucullatus, a giant flightless pigeon endemic to Mauritius, became extinct in the late seventeenth century, and so rapid was the birds’ disappearance, that by the beginning of the nineteenth century even its very existence was questioned. Only four specimens were then recorded in European museums, of which the most famous was the Tradescant or Oxford Dodo, now in the Oxford University Museum of Natural History. It comprised the head and one foot, and unique soft tissue in the form of skin and traces of feathers. The history of this specimen is reviewed, including the still unresolved question of how it came to Britain, and we provide evidence to show that it was stuffed but probably never mounted. The changes of ownership, and its cataloguing and curation in the different museums are also described, along with its varying roles in entertainment, education and research from the earliest years until the nineteenth century. This is part one of a two-part article; the second deals with the Tradescant Dodo from its dissection in the 1840s until the present day.  相似文献   
9.
Today, the Dodo is the most famous species known to have been driven to extinction through human activity. However, it disappeared over a century before Cuvier demonstrated the reality of extinction, and was only one of a huge number of species that died out following early European expansion around the globe. Unlike many other now-extinct Mascarene species, the Dodo's decline and disappearance was not documented by contemporary observers. Repeated settlement changes on Mauritius during the seventeenth century led to protracted ‘cultural amnesia’ over its very existence, and it was widely regarded as mythical by European scientists into the nineteenth century. A series of scientific and socio-cultural hurdles, which all had to be overcome before a given species could be widely appreciated by the general public as an icon of human-caused extinction, are identified and assessed in order to understand how the Dodo returned from scientific death and achieved its tremendous posthumous celebrity. This review indicates that although some ecological and evolutionary factors may have given the Dodo an increased chance of becoming famous, these factors are offset by a much greater series of serendipitous events, emphasising the importance of contingence and the fundamental lack of inevitability in historical processes.

The dodo was (perverse distinction) Immortalized by his extinction  相似文献   
10.
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