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91.
Phukuntsi Metlholo A. Du Plessis Morne Dalton Desiré L. Jansen Raymond Sauther Michelle L. Cuozzo Frank P. Kotze Antoinette 《Primates; journal of primatology》2021,62(4):667-675
Primates - The habitats of Galago moholi are suspected to be largely fragmented, while the species is thought to be expanding further into the southernmost fringe of its range, as well as into... 相似文献
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Albert L. Harting Michelle M. Barbieri Jason D. Baker Tracy A. Mercer Thea C. Johanos Stacie J. Robinson Charles L. Littnan Katie M. Colegrove Dave S. Rotstein 《Marine Mammal Science》2021,37(1):235-250
Identifying, assessing, and ranking the impact of individual threats is fundamental to the conservation and recovery of rare and endangered species. In this analysis, we quantify not only the frequency of specific causes-of-death (CODs) among Main Hawaiian Island (MHI) monk seals, but also assess the impact of individual CODs on the intrinsic growth rate, λ, of the MHI population. We used gross necropsy results, histopathology, and other evidence to assign probabilities of 11 COD types to each mortality and then used Monte Carlo sampling to evaluate the influence of each COD on λ. By right censoring realizations involving specific CODs, we were able to estimate λ (and its associated uncertainty) when CODs were selectively removed from influencing survival. Applying the analysis to all known and inferred deaths believed to have occurred 2004–2019, the CODs with the largest influence on λ were anthropogenic trauma, anthropogenic drowning, and protozoal disease. In aggregate, anthropogenic CODs had a larger effect on the growth rate than either natural or disease CODs. Possible bias associated with differential carcass detection, recovery, and COD classification are discussed. 相似文献
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Mette K. Schiønning Martha Gosch Eileen Dillane Michelle Cronin Mark J. Jessopp 《Marine Mammal Science》2021,37(2):533-545
Recoveries of gray seal (Halichoerus grypus) populations across their eastern Atlantic distribution have led to a steady increase in seal-fishery interactions. Fishers have estimated depredation of salmonids (Salmo spp.) and monkfish (Lophius spp.) as high as 40% and 59% respectively in Ireland. However, empirical evidence for the consumption of these species has been extremely limited due to diagnostic hard part remains not being found in scats or stomach samples. We applied species-specific primers and tested for the presence of monkfish and salmonids in gray seal diet genetically using quantitative polymerase chain reaction (qPCR) on scats. Monkfish occurred in 29.7% of sampled scats, while salmonids occurred in 12.7%. Seasonal and regional variability in occurrence were noted for both species, likely related to the migratory behavior of the prey species and proximity of seal haul-outs to aquaculture sites. Traditional hard part analysis of scats, including scats that tested positive for monkfish and salmonid DNA, failed to find any evidence of either species. This study provides important empirical evidence for the consumption of these species in Ireland that can inform management. 相似文献
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Alice Toso Simona Schifano Charlotte Oxborough Krista McGrath Luke Spindler Anabela Castro Lucy Evangelista Vanessa Filipe Maria José Gonçalves Antonio Marques Inês Mendes da Silva Raquel Santos Maria João Valente Iona McCleery Michelle Alexander 《American journal of physical anthropology》2021,176(2):208-222
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Andreas Lackner Robert Sehlke Marius Garmhausen Giuliano Giuseppe Stirparo Michelle Huth Fabian TitzTeixeira Petra van der Lelij Julia Ramesmayer Henry F Thomas Meryem Ralser Laura Santini Elena Galimberti Mihail Sarov A Francis Stewart Austin Smith Andreas Beyer Martin Leeb 《The EMBO journal》2021,40(8)
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Steffen H. Büttner Eric W. Isemonger Michelle Isaacs Deon van Niekerk Rachel E. Sipler Rosemary A. Dorrington 《Geobiology》2021,19(1):35-47
In the geological record, fossil phosphatic stromatolites date back to the Great Oxidation Event in the Paleoproterozoic, but living phosphatic stromatolites have not been described previously. Here, we report on cyanobacterial stromatolites in a supratidal freshwater environment at Cape Recife, South African southern coast, precipitating Ca carbonate alternating with episodes of Ca phosphate deposition. In their structure and composition, the living stromatolites from Cape Recife closely resemble their fossilized analogues, showing phosphatic zonation, microbial casts, tunnel structures and phosphatic crusts of biogenic origin. The microbial communities appear to be also similar to those proposed to have formed fossil phosphatic stromatolites. Phosphatic domains in the material from Cape Recife are spatially and texturally associated with carbonate precipitates, but form distinct entities separated by sharp boundaries. Electron Probe Micro‐Analysis shows that Ca/P ratios and the overall chemical compositions of phosphatic precipitates are in the range of octacalcium phosphate, amorphous tricalcium phosphate and apatite. The coincidence in time of the emergence of phosphatic stromatolites in the fossil record with a major episode of atmospheric oxidation led to the assumption that at times of increased oxygen release the underlying increased biological production may have been linked to elevated phosphorus availability. The stromatolites at Cape Recife, however, form in an environment where ambient phosphorus concentrations do not exceed 0.28 μM, one to two orders of magnitude below the previously predicted minimum threshold of >5 μM for biogenic phosphate precipitation in paleo‐systems. Accordingly, we contest the previously proposed suitability of phosphatic stromatolites as a proxy for high ambient phosphate concentrations in supratidal to shallow ocean settings in earth history. 相似文献