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51.
Sanna Ojalammi 《Anthrozo?s》2018,31(2):233-246
These days zoos often claim that their main objective is the promotion of nature conservation and that they strive to educate their visitors about animals and nature conservation. But how do zoo visitors themselves perceive this emphasis on conservation education? In order to determine how Helsinki Zoo visitors perceive nature conservation during their visit, we undertook a qualitative analysis of 75 structured situational interviews and five autoethnographical visits. Our results show that there was only a limited understanding of nature conservation among the zoo visitors. Their perception follows the typical framing of nature conservation in zoos: conservation projects that embrace captive breeding, in-situ conservation collaboration, and the reintroduction of those species. Moreover, in the Helsinki Zoo case these perceptions may have been influenced by the fact that the zoo did not give concrete advice on how the visitors themselves can contribute to conservation, except in terms of donating money. Framing nature conservation in such ways distances it from visitors’ everyday lives. 相似文献
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Henry R. Scharf Mevin B. Hooten Ryan R. Wilson George M. Durner Todd C. Atwood 《Biometrics》2019,75(3):810-820
The analysis of animal tracking data provides important scientific understanding and discovery in ecology. Observations of animal trajectories using telemetry devices provide researchers with information about the way animals interact with their environment and each other. For many species, specific geographical features in the landscape can have a strong effect on behavior. Such features may correspond to a single point (eg, dens or kill sites), or to higher dimensional subspaces (eg, rivers or lakes). Features may be relatively static in time (eg, coastlines or home‐range centers), or may be dynamic (eg, sea ice extent or areas of high‐quality forage for herbivores). We introduce a novel model for animal movement that incorporates active selection for dynamic features in a landscape. Our approach is motivated by the study of polar bear (Ursus maritimus) movement. During the sea ice melt season, polar bears spend much of their time on sea ice above shallow, biologically productive water where they hunt seals. The changing distribution and characteristics of sea ice throughout the year mean that the location of valuable habitat is constantly shifting. We develop a model for the movement of polar bears that accounts for the effect of this important landscape feature. We introduce a two‐stage procedure for approximate Bayesian inference that allows us to analyze over 300 000 observed locations of 186 polar bears from 2012 to 2016. We use our model to estimate a spatial boundary of interest to wildlife managers that separates two subpopulations of polar bears from the Beaufort and Chukchi seas. 相似文献
54.
Relative male and female contributions to the supercooling point of their offspring in Microvelia reticulata (Heteroptera: Veliidae) 下载免费PDF全文
Cold hardiness is a key life history trait in temperate and polar ectothermic species, as it affects survival during overwintering, but its evolution is poorly understood. While many studies of cold hardiness in insects have shown differences between species, populations or developmental stages, data on the relative contribution of individual genotypes to cold hardiness are scarce and mainly limited to drosophilid fly species. We used a sib‐analysis (paternal half‐sib/full‐sib breeding design) to estimate the relative contributions of parental generation to the supercooling point (SCP) of the offspring of a heteropteran non‐model insect species, Microvelia reticulata (Heteroptera: Gerromorpha: Veliidae). We found that parent identity affected significantly SCP values of their offspring. Magnitudes of estimated sire and dam variance components were similar but the distributions of individual contributions to SCP differed between sires and dams, which points to sex‐specific genetic or parental effects on SCP in this species. The animal model failed to find a realistic estimate of heritability (h2) of SCP, suggesting that the underlying genetics of SCP in M. reticulata can not be characterized by purely additive effects. 相似文献
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Understanding the mechanisms of inhibitors of translation termination may inform development of new antibacterials and therapeutics for premature termination diseases. We report the crystal structure of the potent termination inhibitor blasticidin S bound to the ribosomal 70S?release factor 1 (RF1) termination complex. Blasticidin S shifts the catalytic domain 3 of RF1 and restructures the peptidyl transferase center. Universally conserved uridine 2585 in the peptidyl transferase center occludes the catalytic backbone of the GGQ motif of RF1, explaining the structural mechanism of inhibition. Rearrangement of domain 3 relative to the codon-recognition domain 2 provides insight into the dynamics of RF1 implicated in termination accuracy. 相似文献
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动物胃肠道微生物对生产性能提高具有重要的作用,因此营养、微生物组与生产表型的互作研究已经成为国际研究热点。综述了2016年动物胃肠道微生物组学研究取得的十项重要成果,这些成果通过组学方法,研究了瘤胃纤维分解菌和尿素分解菌的功能基因多样性,揭示了微生物群落与日粮营养素、宿主基因型、环境的互作关系,阐明了反刍动物生产表型相关的瘤胃微生物种类和功能;首次构建猪肠道微生物组参考基因集,解析猪全肠道黏膜微生物组成,阐明了猪增重相关肠道微生物种类。这十大亮点成果将为国内动物营养学家开展动物胃肠道微生物组学研究提供参考。 相似文献
57.
Jane M. Reid 《Proceedings. Biological sciences / The Royal Society》2012,279(1747):4652-4660
The evolutionary forces that underlie polyandry, including extra-pair reproduction (EPR) by socially monogamous females, remain unclear. Selection on EPR and resulting evolution have rarely been explicitly estimated or predicted in wild populations, and evolutionary predictions are vulnerable to bias due to environmental covariances and correlated selection through unmeasured traits. However, evolutionary responses to (correlated) selection on any trait can be directly predicted as additive genetic covariances (covA) with appropriate components of relative fitness. I used comprehensive life-history, paternity and pedigree data from song sparrows (Melospiza melodia) to estimate covA between a female''s liability to produce extra-pair offspring and two specific fitness components: relative annual reproductive success (ARS) and survival to recruitment. All three traits showed non-zero additive genetic variance. Estimates of covA were positive, predicting evolution towards increased EPR, but 95% credible intervals overlapped zero. There was therefore no conclusive prediction of evolutionary change in EPR due to (correlated) selection through female ARS or recruitment. Negative environmental covariance between EPR and ARS would have impeded evolutionary prediction from phenotypic selection differentials. These analyses demonstrate an explicit quantitative genetic approach to predicting evolutionary responses to components of (correlated) selection on EPR that should be unbiased by environmental covariances and unmeasured traits. 相似文献
58.
Ya. N. Shoikhet V. I. Kiselev E. V. Zaitsev I. B. Kolyado B. Yu. Konovalov S. Bauer B. Grosche W. Burkart 《Radiation and environmental biophysics》1999,38(3):207-210
A registry of the rural population in the Altai region exposed to fallout from nuclear tests at the Semipalatinsk test site
(STS) was established more than four decades after the first Soviet nuclear explosion on August 29, 1949. Information about
individuals living in an exposed and a control area was collected using all available local sources, such as kolkhoz documentation, school registries, medical treatment records and interviews with residents. As a result, a database comprising
an exposed group of 39 179 individuals from 53 Altai region villages, 6769 external and 3303 internal controls was compiled.
For several settlements, effective dose estimates reached the level of 1.5 Sv, while the average effective dose estimate in
the exposed group was 340 mSv. Dosimetric data, vital status information and health records gathered at rayon and village
medical facilities are held in the registry. Cause-of-death information for deceased residents is obtained from death registration
forms archived at the Altai region vital statistics office. At present, a follow-up of approximately 40% of the population
exposed in 1949 has been done. More will be added by searching for migrants to the larger towns of the Altai region, i.e.
Barnaul, Rubtsovsk and Biisk. In order to assess the influence of radiation exposure, analytical studies with a case-control
design for stomach and lung cancer are currently being prepared. The number of known cases is sufficient to detect an odds
ratio of 1.5 at the 95% confidence level. Epidemiological studies in populations affected by fallout from STS may be equally
important to the atomic bomb survivors’ study for the direct quantification of radiation effects. The range of exposure rates
experienced will extend the acute high-dose-rate findings from Hiroshima/Nagasaki towards acute and protracted lower exposures,
which are more relevant for radiation protection issues.
Received: 3 March 1999 / Accepted in revised form: 8 June 1999 相似文献
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