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2021 ◽  
Author(s):  
Ian Moffat

In 2011, Gunn et al. published the discovery in a remote part of the western Arnhem Land plateau of a rock painting that closely resembles the most recent reconstructions of an extinct megafaunal bird, the dromornithid Genyornis newtoni. Characteristics of the painting distinguish it from depictions of other bird species and support its identification as G. newtoni: a deep convex bill, unlike the shallow bill of an emu or cassowary; a globular cranium and relatively thick neck; indication of a crop (emus and cassowaries lack crops); non-pendulous posture of the wing (unlike the pendulous posture of emus); the proportions of the pelvic limb showing long tibiotarsi and stout tarsometatarsi; the short, broad toes that appear to terminate in blunt claws; and a dorsal profile paralleling that of reconstructed dromornithids and unlike an emu or any species of cassowary, in which the vertex of the back is more anterior. The several points of special resemblance between the painting and reconstructions of the extinct bird based on paleontological evidence led Gunn et al. (2011:10) to conclude, ‘on the basis of probability the painting is indeed a representation of Genyornis newtoni’. This finding brings a conundrum. If the painting is indeed a contemporaneous depiction of G. newtoni, it becomes the oldest painting known in the world, for the bird is thought to have become extinct around 50,000 +/- 5000 years ago (Miller et al. 1999; Roberts and Brook 2010; Roberts et al. 2001) or even earlier (see Grellet-Tinner et al. 2016). Or that timing for the extinction of Genyornis is wrong; or a relic population survived longer on the Arnhem Land plateau (e.g. Murray and Vickers-Rich 2004), perhaps until the Last Glacial Maximum (LGM), which commenced around 25,000 years ago. And, as Gunn et al. (2011) acknowledged, there are still other alternatives. The painting might be of a ‘mythological’ animal: either one rooted in ancient memory of G. newtoni, as has been suggested for the ‘mihirung’ of southern Australian Aboriginal peoples (Vickers-Rich 1987) – although in societies without writing, social memory has not been found anywhere in the world to reliably extend in recognisable form over very long periods of time (cf. Bradley 2002) – or of a creature without a material counterpart that fortuitously resembled the fossil bird. The painting occurs on a vertical rock wall under a shallow overhang. Could the motif really have survived there since Pleistocene times, whether 25,000 or 50,000 years ago? And the painting shows a speared bird, so it could be the first evidence for the hunting of extinct megafauna in Australia. With these enigmas in mind, the Jawoyn Association asked us in 2010 to study the ‘Genyornis’ site, to investigate the age of the art and its archaeological and geomorphological context. Our major aims were to ask whether the painting dates, or theoretically could date, to the time of G. newtoni, or whether it must be more recent, and to uncover contextual ancient cultural information relating to the artworks and to occupation activities at the site in the past. Here, we present the results of these archaeological and geomorphological investigations along with a summary of the chemistry of the rock surface that houses the painting of the large bird thought by Gunn et al. (2011) to be of a Genyornis.


2021 ◽  
Vol 10 (2) ◽  
pp. 141-149
Author(s):  
Anna Andreevna Malyutina ◽  
Maxim Mikhailovich Charniauski

In 2010, during the investigation of the site Asaviec 2 (Krivina peat bog, Beankovičy District, Viciebsk Region, Belarus) a unique set of tools in a case was revealed. It consists of an ornamented case made of the tubular bone of a large bird, an awl made of the lateral metapody of an elk, and a pointed bone item with an extension in the form of a wedge at one end. The method of experimental-traceological analysis was employed to determine the details of the manufacturing technology and the functional purpose of the find. According to the results of the study, a separate use of the tools was established - working with plant materials, which may indicate evidence of knitting or weaving products from organic fibers. Following experimental observations, some possible ways of working with these implements are considered. Thus, on the basis of the structural and contextual features of the artefacts, a variant of their use in a composite form, where the case served also as a handle is proposed. Bone awls or points are a widespread type of tools on sites from the Stone to the Bronze Age. However, the unique set found in situ allows us to expand our knowledge of the economy and productive activities of the past. Archaeological material, revealed an accompanying set of tools and a radiocarbon date from the underlying finding of conditional layer - 3810 50 BP (cal BC 2460-2064) (Le 10465), allow us to reconcile it with the antiquities of the Zhyzhyca-Kryvina stage of the Northern Belarusian Culture, middle of the 3rd-first half of the 2nd mill. BC.


2021 ◽  
Vol 9 ◽  
Author(s):  
Daniel Burgas ◽  
Otso Ovaskainen ◽  
F. Guillaume Blanchet ◽  
Patrik Byholm

Despite the wide recognition that strongly interacting species can influence distributions of other species, species interactions are often disregarded when assessing or projecting biodiversity distributions. In particular, it remains largely uncharted the extent to which the disappearance of a keystone species cast repercussions in the species composition of future communities. We tested whether an avian top predator can exert both positive and negative effects on spatial distribution of other species, and if these effects persist even after the predator disappeared. We acquired bird count data at different distances from occupied and non-occupied nests of Northern goshawks Accipiter gentilis. Using a Bayesian joint species distribution model, we found that large bird species (preferred prey) are less abundant in the proximity of nests occupied by goshawks, whereas smaller species –expected to get protection from subordinate predators displaced by goshawks– more often showed an opposite association. These spatial differences level off gradually, but still persist for years after the goshawks have disappeared. This indicates that the composition of local bird populations and communities might be conditional on past species interactions. Therefore, endeavors centered around species distributions could largely benefit from acknowledging the local extinction of keystone species.


Author(s):  
Dominik Marchowski

1. The use of a drone to count the flock sizes of 33 species of waterbirds during the breeding and non-breeding periods was investigated. 2. In 96% of 343 cases, drone counting was successful. 18.8% of non-breeding birds and 3.6% of breeding birds exhibited adverse reactions: in the former, the birds were flushed, whereas the latter attempted to attack the drone. 3. The automatic counting birds was best done with the microbiology software - ImageJ / Fiji: the average bird counting rate was 100 birds in 82 seconds. 4. Machine learning using neural network algorithms proved to be an effective and fast way of counting birds – 100 birds in 23 seconds. However, as the preparation of images and machine learning time are time-consuming, this method is recommended only for large data sets and large bird assemblages. 5. The responsible study of wildlife using a drone should only be carried out by persons experienced in the biology and behaviour of the animals concerned.


2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Gang Luo ◽  
Chi Ma ◽  
Wei Chen ◽  
Lulu Liu ◽  
Zhenhua Zhao

The high bypass ratio turbofan engine’s load-carrying structure transient response during bird ingestion was analyzed in accordance with the engine bird ingestion certification regulations, the principles of structural safety assessment were represented, and the structural safety analysis and assessment method of Turbo-Fan engine during bird ingestion were proposed. A high bypass ratio turbofan engine’s FEM was established and verified the rationality when its’ operation. Large bird ingestion into an engine’s procedure was conducted, the dynamic responses of key components on engine’s load-carrying structures during the bird ingestion were discussed, and the safety assessment consequence was obtained. We draw a conclusion that the relevant analysis/simulation data could be submitted to engine certification administration as key documents, the structural safety analysis and assessment method of turbofan engine due to bird ingestion could be applied as analysis and prediction work in the engine bird ingestion certification.


2020 ◽  
Vol 110 ◽  
pp. 104412 ◽  
Author(s):  
Lida Xing ◽  
Ryan C. McKellar ◽  
Jingmai K. O'Connor
Keyword(s):  

2019 ◽  
Vol 68 (270) ◽  
pp. 371
Author(s):  
Bernardino Leers
Keyword(s):  
X Ray ◽  

O título abre um panorama largo e complexo. Sugere o vôo alto de uma águia no céu azul por cima das montanhas. Mas homem maduro é prudente, até cauteloso. Sabe que não tem asas para voar. Ao menos no centro do Brasil, o pássaro que voa nas alturas não é águia. É urubu. Em vez de ficar sonhando ou querendo voar como um grande pássaro de asas largas, toda iniciativa humana moral começa com os seres humanos, como são, onde estão pisando na terra e quais possibilidades eles têm para responder às chamadas de Deus e às necessidades dos próximos. Fazer uma radiografia da contextualização do referido apelo moral e de suas possibilidades, no Brasil, hoje, é objeto do ensaio do Autor.Abstract: The title opens a large and complex panorama. It suggests the flight of an eagle, high up in the blue skies above the mountains. But the mature man is prudent, even cautious. He knows he has no wings and cannot fly. At least in the brazilian hinterland the bird flying high is not the eagle but the vulture. Instead of day-dreaming or hoping to fly like a large bird with huge wings, we must remember that every moral human initiative begins with the human beings as they actually are, on the ground where they stand and with the possibilities they have of answering God’s summons and to his/her fellow beings’needs. The objective of the Author’s essay is to take an X-ray of the context of this moral appeal and the possibilities of its realization in contemporary Brazil.


2019 ◽  
Vol 11 (4) ◽  
pp. 13492-13496 ◽  
Author(s):  
Alex Leigh Brighten ◽  
Robert John Burnside

Little is known about the ecology of the Sand Cat Felis margarita throughout its range in the deserts of northern Africa to central Asia.  We present observations of the Sand Cat in the southern Kyzylkum Desert, Uzbekistan, potentially preying upon a large bird and returning to the kill on subsequent nights.  This record contributes to the knowledge about the feeding ecology and varied diet of the Sand Cat and its opportunistic hunting strategy.


2019 ◽  
Vol 35 (2) ◽  
pp. 68-73 ◽  
Author(s):  
Victor H. Montalvo ◽  
Carolina Sáenz-Bolaños ◽  
Luis D. Alfaro ◽  
Juan C. Cruz ◽  
Flavio H. Guimarães-Rodrigues ◽  
...  

AbstractTemporal and spatial scarcity of water in semi-arid and seasonal ecosystems often leads to changes in movements and behaviour of large vertebrates, and in the neotropics this dynamic is poorly understood due to logistical and methodological limitations. Here we used camera trapping to elucidate variation in patterns of seasonal use of waterholes and pathways by 10 large-mammal and four large-bird species in the dry forest of north-western Costa Rica. From 2011 to 2015, we deployed trail cameras at 50 locations, including waterholes and three types of pathway (roads, human trails and animal paths). We used Generalized Linear Models to evaluate the effect of location and seasonality on the rates at which independent photographs were taken. We found interacting effects of location and seasonality for the capuchin monkey (Cebus capucinus), the tiger heron (Trigrisoma mexicanum), the white-tailed deer (Odocoileus virginianus) and the tapir (Tapirus bairdii) suggesting that these species were the most influenced by waterholes during the dry season. Comparison of waterhole sites and specific types of pathways (roads, animal paths and human trails) showed that location influenced photo-capture rates of almost all species, suggesting a useful insight to avoid and account for bias in camera trap studies. Furthering our ecological understanding of seasonal water regimes and large vertebrates’ behaviours allow for better understanding of the consequences of climate change on them.


2018 ◽  
Vol 93 (2) ◽  
pp. 359-367 ◽  
Author(s):  
Gerald Mayr ◽  
Philip D. Gingerich ◽  
Thierry Smith

AbstractWe revisit the holotype of Calcardea junnei Gingerich, 1987 from the latest Paleocene (Clarkforkian) of the Willwood Formation (Wyoming, USA). The species is based on a partial skeleton and was originally assigned to the Ardeidae (herons). As we show, this classification cannot be upheld and Calcardea Gingerich, 1987 more closely resembles the taxon Vastanavis Mayr et al., 2007 (Vastanavidae), a parrot-like bird from the early Eocene of India. Even though C. junnei is a large bird, its long wings and short tarsometatarsus argue against a predominantly terrestrial way of living, and the morphology of the tarsometatarsus and pedal phalanges instead suggest strong grasping feet. We conclude that an assignment of Calcardea to the landbird clade (Telluraves) is better supported than its classification into the waterbird clade (Aequornithes), which includes Ardeidae and other ‘ciconiiform’ and ‘pelecaniform’ taxa. Calcardea junnei is one of the oldest known representatives of Telluraves and its morphology shows plesiomorphic features, which contributed to its previous misidentification as a heron. Calcardea exhibits a distinctive osteology and affords a glimpse of a previously unknown late Paleocene avian morphotype.


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