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1.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34580213

RESUMEN

How early human foragers impacted insular forests is a topic with implications across multiple disciplines, including resource management. Paradoxically, terminal Pleistocene and Early Holocene impacts of foraging communities have been characterized as both extreme-as in debates over human-driven faunal extinctions-and minimal compared to later landscape transformations by farmers and herders. We investigated how rainforest hunter-gatherers managed resources in montane New Guinea and present some of the earliest documentation of Late Pleistocene through mid-Holocene exploitation of cassowaries (Aves: Casuariidae). Worldwide, most insular ratites were extirpated by the Late Holocene, following human arrivals, including elephant birds of Madagascar (Aepyornithidae) and moa of Aotearoa/New Zealand (Dinornithiformes)-icons of anthropogenic island devastation. Cassowaries are exceptional, however, with populations persisting in New Guinea and Australia. Little is known of past human exploitation and what factors contributed to their survival. We present a method for inferring past human interaction with mega-avifauna via analysis of microstructural features of archaeological eggshell. We then contextualize cassowary hunting and egg harvesting by montane foragers and discuss the implications of human exploitation. Our data suggest cassowary egg harvesting may have been more common than the harvesting of adults. Furthermore, our analysis of cassowary eggshell microstructural variation reveals a distinct pattern of harvesting eggs in late ontogenetic stages. Harvesting eggs in later stages of embryonic growth may reflect human dietary preferences and foraging seasonality, but the observed pattern also supports the possibility that-as early as the Late Pleistocene-people were collecting eggs in order to hatch and rear cassowary chicks.


Asunto(s)
Huevos , Paleognatos , Bosque Lluvioso , Animales , Cáscara de Huevo , Conducta Alimentaria , Nueva Guinea , Paleognatos/fisiología
2.
Zoo Biol ; 42(2): 296-307, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36070084

RESUMEN

The ability to monitor developing avian embryos and their associated vascular system via candling enables the application of important reproductive management techniques. Egg candling facilitates the confirmation of egg viability throughout the incubation process and identification of a precise position on a vein for the safe extraction of blood. Blood samples may then be analysed to retrieve vital health and genetic information to assist in conservation management. However, the thick or opaque egg shell characteristics of some avian species prevents the observation of egg contents using traditional candling methods, thus limiting management options. This paper tests a novel method of preparing thick-shelled or opaque eggs so that traditional egg candling and blood extraction methods may be applied. Eggs from captive emu (Dromaius novaehollandiae, Latham 1790) and southern cassowary (Casuarius casuarius johnsonii, Linnaeus 1758) were obtained, and partial fenestration was performed on two areas of shell either before incubation or at ⅓ of incubation. Hatchability and weight loss were examined as a measure of effect of the fenestration process on the developing embryo. Clear observation of vascular development was successful in 97% of viable fenestrated eggs, without affecting hatchability or weight loss. Blood samples were taken from developing embryos and DNA was successfully extracted for proof of concept of this new technique. The ability to observe vascular development and monitor the developing embryo in thick and opaque eggs will significantly improve both in situ and ex situ population management options such as in ovo sexing in species of concern.


Asunto(s)
Animales de Zoológico , Aves , Animales , Pérdida de Peso , Reproducción , Cáscara de Huevo , Óvulo
3.
BMC Evol Biol ; 19(1): 233, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31881941

RESUMEN

BACKGROUND: Palaeognathae is a basal clade within Aves and include the large and flightless ratites and the smaller, volant tinamous. Although much research has been conducted on various aspects of palaeognath morphology, ecology, and evolutionary history, there are still areas which require investigation. This study aimed to fill gaps in our knowledge of the Southern Cassowary, Casuarius casuarius, for which information on the skeletal systems of the syrinx, hyoid and larynx is lacking - despite these structures having been recognised as performing key functional roles associated with vocalisation, respiration and feeding. Previous research into the syrinx and hyoid have also indicated these structures to be valuable for determining evolutionary relationships among neognath taxa, and thus suggest they would also be informative for palaeognath phylogenetic analyses, which still exhibits strong conflict between morphological and molecular trees. RESULTS: The morphology of the syrinx, hyoid and larynx of C. casuarius is described from CT scans. The syrinx is of the simple tracheo-bronchial syrinx type, lacking specialised elements such as the pessulus; the hyoid is relatively short with longer ceratobranchials compared to epibranchials; and the larynx is comprised of entirely cartilaginous, standard avian anatomical elements including a concave, basin-like cricoid and fused cricoid wings. As in the larynx, both the syrinx and hyoid lack ossification and all three structures were most similar to Dromaius. We documented substantial variation across palaeognaths in the skeletal character states of the syrinx, hyoid, and larynx, using both the literature and novel observations (e.g. of C. casuarius). Notably, new synapomorphies linking Dinornithiformes and Tinamidae are identified, consistent with the molecular evidence for this clade. These shared morphological character traits include the ossification of the cricoid and arytenoid cartilages, and an additional cranial character, the articulation between the maxillary process of the nasal and the maxilla. CONCLUSION: Syrinx, hyoid and larynx characters of palaeognaths display greater concordance with molecular trees than do other morphological traits. These structures might therefore be less prone to homoplasy related to flightlessness and gigantism, compared to typical morphological traits emphasised in previous phylogenetic studies.


Asunto(s)
Laringe/anatomía & histología , Paleognatos/anatomía & histología , Paleognatos/genética , Filogenia , Animales , Evolución Biológica , Femenino , Glotis/anatomía & histología , Masculino , Orofaringe/anatomía & histología , Paleognatos/clasificación , Vocalización Animal
4.
J Vet Med Sci ; 85(6): 667-671, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37150614

RESUMEN

An adult 22-year-old, male southern cassowary (Casuarius casuarius) presented for lethargy, dysorexia and soft feces. Clinical findings under chemical immobilization were unremarkable except for heterophilic toxic changes on blood smear, reduced albumin/globulin ratio and potentially elevated liver parameters. The animal was treated for suspected hepatobiliary insufficiency and received supportive treatment with daily subcutaneous fluids and medication and was monitored with a quality-of-life assessment. It was eventually euthanized after further deterioration. Post-mortem examination revealed vegetative valvular endocarditis, bile duct obstruction, cholangiohepatitis and splenitis with intralesional Enterococcus casseliflavus isolated. This is a first documented case of E. casseliflavus infection in a bird with multiorgan involvement.


Asunto(s)
Infecciones Bacterianas , Enterococcus , Animales , Masculino , Infecciones Bacterianas/veterinaria , Aves
5.
Aust Vet J ; 92(7): 240-5, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24964832

RESUMEN

BACKGROUND: The southern cassowary (Casuarius casuarius johnsonii) attains 1.8 m in height and over 80 kg in weight. These large birds are equipped with large claws and, although not a direct threat to humans, they have caused serious injury to handlers and members of the public. METHODS AND RESULTS: This study describes chemical immobilisation, restraint, transport and post-monitoring (satellite tracking) methodologies for adult and juvenile southern cassowaries, captured and released from their natural environment. CONCLUSIONS: The described methods have improved the management and research opportunities for the southern cassowary and may be transferable to other species of large ratite.


Asunto(s)
Anestésicos Disociativos/administración & dosificación , Ansiolíticos/administración & dosificación , Inmovilización/veterinaria , Struthioniformes , Tiletamina/administración & dosificación , Zolazepam/administración & dosificación , Animales , Combinación de Medicamentos , Femenino , Sistemas de Información Geográfica , Inmovilización/métodos , Masculino , Queensland , Telemetría/métodos , Telemetría/veterinaria
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