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John Gould James Taylor Bryce Davies Rachael Donelly Kate Schmahl Cassandra K. Bugir Chad T. Beranek Jess McGregor Stephen V. Mahony Rebecca Seeto Rose Upton Colin McHenry Alex Callen 《Austral ecology》2023,48(3):585-599
Traditional methods for identifying individual amphibians in capture–mark–recapture (CMR) studies have been primarily confined to post-metamorphic stages, using artificial markers that come with a variety of limitations. An alternative that may open CMR studies to earlier life stages involves the use of a species' natural external markers in photo-based identification. In this study, we investigated whether it was possible to distinguish tadpoles of the threatened green and golden bell frog (Litoria aurea) at the individual level based on tail venation patterns. We collected photographs of the tails of captive-raised tadpoles using a smartphone over a 4-week period. This photo-library was used to create an electronic survey where participants were asked to detect matches for query tadpoles from small image pools. We found that most participants agreed on a match for each query, with perfect consensus achieved for most queries (83%). We detected a 14% decline in perfect consensus when participants were asked to match images of tadpoles separated by longer time intervals, suggesting that it is more difficult to visually identify recapture events of L. aurea tadpoles over extended periods due to changes to tail appearance. However, consensus was obtained by participants for all queries, with all matches verified as being correct by the primary researcher. The strength of agreement among participants with no prior experience in matching tadpole tails suggests that there is sufficient inter-individual variation in this feature for individuals to be manually identified. We thus propose that photo-identification is likely to be a valid, non-invasive technique that can be used for short-term studies on tadpole populations that display tail venation. This offers an alternative to artificial markers that may not allow for individual identification, while also opening up tadpole monitoring programmes to citizen scientists who can be recruited online to process image data from home. 相似文献
673.
K H McGregor J Gil S Lahiri 《Journal of applied physiology (Bethesda, Md. : 1985)》1984,57(5):1430-1438
We performed morphometric studies of carotid body in acutely and chronically hypoxic rats (inspired PO2 = 70 Torr, at sea level). Acute exposure was for the duration of about 10 min, and chronic exposure lasted for 28 days. We confirmed that the total volume of the organ increased by severalfold. At the light-microscopy level we found an enlargement of the volume density of the blood sinuses from 14 to 31% due to chronic hypoxia. The morphometric hematocrit increased from 39 to 70% paralleling changes in the conventionally measured venous hematocrit. These data do not show any specific plasma skimming in the carotid body blood vessels. With the electron microscope we found that the mean average volume of type I cells increased from 320 micron3 in controls to 1,120 micron3 in the chronically hypoxic rats without hyperplasia, whereas type II cells had increased in number without alteration in size. Qualitative observations revealed that the normal appearance of clusters of ovoid type I cells interspersed by capillaries had been transformed into a pattern of individual cells forming plates between expanded blood vessels with a large increase of contact area between the cells and vessels. Type II cells appeared to have proliferated without changes in individual size to cover the enlarged periphery of type I cells. The observed structural changes in the carotid body parenchyma and vasculature appear to be physiologically adaptive and provide further support for the idea that various elements in the organ are particularly sensitive to hypoxia. 相似文献
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G. McGregor Reid 《Journal of fish biology》2017,90(5):1695-1699
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Sarah Abou Alaiwi Amin H. Nassar Elio Adib Stefan M. Groha Elie W. Akl Bradley A. McGregor Edward D. Esplin Shan Yang Kathryn Hatchell Vincent Fusaro Sarah Nielsen David J. Kwiatkowski Guru P. Sonpavde Mark Pomerantz Judy E. Garber Matthew L. Freedman Huma Q. Rana Alexander Gusev Toni K. Choueiri 《Cell reports》2021,34(13):108926
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Corinna Erckenbrecht Maureen Fuary Shelley Greer Rosita Henry Russell McGregor Michael Wood 《The Australian journal of anthropology》2010,21(3):350-366
This paper outlines some of the ways early artefact collecting contributed to the definition of the Australian region now known and marketed as the ‘World Heritage Wet Tropics’. While others have collected in this region, we focus on the collecting activities of Hermann Klaatsch and the work of Norman Tindale to explore some factors that contributed to their claims that certain artefacts represent a region and its history. We argue that these understandings of region and the past, along with the now widely dispersed artefacts, maintain a lively, albeit transformed, presence in current debates about Aboriginal regional culture, linking assertions of rights to lost and stolen cultural property with notions of large‐scale environmental management within the ‘Wet Tropics’. 相似文献
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