The microstructure and composition of the layers of two giant avian eggshells were investigated using a combination of scanning electron microscopy, electron probe microanalyses, and X-ray absorption near-edge structure spectroscopy (XANES). The two species have some similarities and differences in their microstructure and composition; the composition is not homogeneous throughout the eggshell thickness. XANES studies show that sulfur is associated with amino acids in the inner organic membranes, whereas in the mineralised layers the sulfur is mainly associated with sulfated polysaccharides. These results are similar to those obtained on chicken eggshells, and confirm the active role of sulfated acidic polysaccharides in biomineralisation processes of carbonate skeletons.
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http://dx.doi.org/10.1007/s00216-006-0784-8 | DOI Listing |
Sci Total Environ
January 2025
School of Biological Sciences, University of Adelaide, Adelaide, SA 5000, Australia; The Environment Institute, University of Adelaide, Adelaide, SA 5000, Australia; Center for Macroecology, Evolution, and Climate, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark; Center for Global Mountain Biodiversity, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark. Electronic address:
Human overexploitation contributed strongly to the loss of hundreds of bird species across Oceania, including nine giant, flightless birds called moa. The inevitability of anthropogenic moa extinctions in New Zealand has been fiercely debated. However, we can now rigorously evaluate their extinction drivers using spatially explicit demographic models capturing species-specific interactions between moa, natural climates and landscapes, and human colonists.
View Article and Find Full Text PDFBMC Genomics
January 2025
Shaanxi Key Laboratory of Qinling Ecological Security, Shaanxi Institute of Zoology, Xi'an, 710032, China.
Background: The relict gull (Larus relictus, Charadriiformes, Laridae) classified as vulnerable in the IUCN Red List is defined as a first-class national protected bird in China. However, our knowledge of the evolutionary history of L. relictus is limited.
View Article and Find Full Text PDFGenes (Basel)
December 2024
Shaanxi Key Laboratory of Qinling Ecological Security, Shaanxi Institute of Zoology, Xi'an 710032, China.
Background: Plovers (Charadriidae), within the order of Charadriiformes, a group of modern birds distributed worldwide, are a frequent subject of molecular phylogenetic studies. While research on mitochondrial genome (mitogenome) variation within the family Charadriidae, especially intraspecific variation, is limited. Additionally, the monophyly of and the phylogenetic placement of remain contentious.
View Article and Find Full Text PDFPol J Vet Sci
December 2024
Department of Animal Welfare and Research, University of Warmia and Mazury in Olsztyn, Oczapowskiego 5, Poland.
Poultry scientists are constantly studying different breeds of cockerels that would be suitable for capon meat production. Capon meat, although not yet very popular, is characterized by exceptional taste qualities that could appeal to many customers. Obtaining the appropriate palatability, structure and tenderness of capon meat is possible thanks to the reduction in androgen levels following the castration of roosters.
View Article and Find Full Text PDFPeerJ
December 2024
Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China.
, the earliest known ceratopsian, is represented by dozens of specimens of different sizes collected from the Upper Jurassic of the Junggar Basin, northwestern China. Here, we present the first comprehensive study on the bone histology of based on ten specimens varying in size. Four ontogenetic stages are recognized: early juvenile, late juvenile, subadult, and adult.
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