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1.
Nature ; 626(7998): 319-326, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326596

RESUMO

Late Pleistocene ice-age climates are routinely characterized as having imposed moisture stress on low- to mid-latitude ecosystems1-5. This idea is largely based on fossil pollen evidence for widespread, low-biomass glacial vegetation, interpreted as indicating climatic dryness6. However, woody plant growth is inhibited under low atmospheric CO2 (refs. 7,8), so understanding glacial environments requires the development of new palaeoclimate indicators that are independent of vegetation9. Here we show that, contrary to expectations, during the past 350 kyr, peaks in southern Australian climatic moisture availability were largely confined to glacial periods, including the Last Glacial Maximum, whereas warm interglacials were relatively dry. By measuring the timing of speleothem growth in the Southern Hemisphere subtropics, which today has a predominantly negative annual moisture balance, we developed a record of climatic moisture availability that is independent of vegetation and extends through multiple glacial-interglacial cycles. Our results demonstrate that a cool-moist response is consistent across the austral subtropics and, in part, may result from reduced evaporation under cool glacial temperatures. Insofar as cold glacial environments in the Southern Hemisphere subtropics have been portrayed as uniformly arid3,10,11, our findings suggest that their characterization as evolutionary or physiological obstacles to movement and expansion of animal, plant and, potentially, human populations10 should be reconsidered.


Assuntos
Ecossistema , Umidade , Camada de Gelo , Animais , Humanos , Migração Animal , Austrália , Temperatura Baixa , Clima Desértico , História Antiga , Plantas , Pólen , Volatilização
2.
J Wildl Dis ; 49(4): 1009-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24502731

RESUMO

In 2009, an outbreak of white nodular cutaneous lesions was detected in one of only two known breeding colonies of the critically endangered southern bentwing bat (Miniopterus schreibersii bassanii), at Naracoorte, South Australia. Necropsies were conducted on 10 euthanized bats in September 2009. In October 2009, 123 bats were examined under anesthesia, with skin biopsies collected from 18 affected bats. Prevalence of skin lesions was 45.2%. The prevalence among males was three times greater than among females. The majority of lesions examined histologically were granulomas, typically centered on a nematode. A single lesion had epidermal hyperplasia with intracytoplasmic inclusions consistent with a pox virus; pox virions were identified on electron microscopy. Nematodes dissected from frozen lesions were identified morphologically as Riouxgolvania beveridgei, previously described in the eastern bentwing bat (Miniopterus schreibersii oceanensis). The factors contributing to this apparent disease emergence and outbreak remain undetermined. Lesions consistent with white nose syndrome were not identified.


Assuntos
Quirópteros , Surtos de Doenças/veterinária , Nematoides/classificação , Infecções por Nematoides/veterinária , Dermatopatias Parasitárias/veterinária , Animais , Feminino , Masculino , Infecções por Nematoides/epidemiologia , Dermatopatias Parasitárias/epidemiologia , Dermatopatias Parasitárias/parasitologia , Austrália do Sul/epidemiologia
3.
Mycologia ; 103(5): 959-68, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21642344

RESUMO

The fungal diversity in areas accessible and not accessible to tourists at UNESCO World Heritage-listed Naracoorte Caves was investigated with culture-dependent and culture-independent techniques for assistance in cave management protocol development. The caves were selected based on tourist numbers and configurations: Stick Tomato (open, high numbers), Alexandra (lockable openings, high numbers) and Strawhaven (control; no access). Culture-based survey revealed Ascomycota dominance irrespective of sampling area with Microascales (Trichurus sp.) being most frequently isolated. Some Hypocreales-like sequences belonging to Fusarium sp., Trichoderma sp. and Neonectria sp. (Stick Tomato) were cultured only from areas not accessible to tourists. These orders also were detected by DGGE assay irrespective of sampling area. The predominance of Ascomycota (especially Microascales) suggested their important ecological roles in these caves. Culture-independent analysis showed higher Shannon fungal diversity values (from ITS-based DGGE profiles) in tourist-accessible areas of these caves than in inaccessible areas with the fungal community banding patterns being substantially different in Stick Tomato Cave. Further investigations are needed to determine the cause of the differences in the fungal communities of Stick Tomato Cave, although cave-related factors such as use, configuration and sediment heterogeneity might have contributed to these differences.


Assuntos
Cavernas/microbiologia , Ecossistema , Fungos/genética , Fungos/isolamento & purificação , Consórcios Microbianos/genética , Filogenia , Microbiologia do Solo , Ascomicetos/isolamento & purificação , Austrália , Biodiversidade , DNA Fúngico/análise , Fusarium/isolamento & purificação , Reação em Cadeia da Polimerase , Trichoderma/isolamento & purificação
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