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81.
Benjamin D. Charlton Ronald R. Swaisgood Zhang Zhihe Rebecca J. Snyder 《Behavioral ecology and sociobiology》2012,66(6):969-974
Although androgen-dependant traits are predicted to signal overall male quality, no study has examined the response of a nonhuman animal to variation in a known acoustic cue to male androgen levels (steroid hormones that are key drivers of male sexual behaviour). Here, we use a single-speaker approach to present male and female giant pandas with re-synthesised male bleats representing callers with high and low androgen levels. Our results revealed that male and female giant pandas had significantly greater-looking responses, spent more time pacing, and were faster to respond to playbacks of bleats simulating high androgen males. When we analysed the sexes separately, a slightly different response pattern was revealed: whereas males and females still had significantly greater-looking responses and were faster to respond to bleats simulating high androgen males, only male giant pandas tended to spend more time pacing. These findings suggest that vocal cues to male androgen levels are functionally relevant to male and female giant pandas during the breeding season, and constitute the first demonstration that a nonhuman animal could be using a vocal signal to assess male hormonal state. We go on to discuss the ecological relevance of signalling androgen levels in this species’ sexual communication and the possible application of our results to conservation breeding. 相似文献
82.
The biochemical response of wild sticklebacks collected in Autumn 2005 at seven stations in the North of France was studied using a set of complementary biomarkers. Here, data on biotransformation of xenobiotics, oxidative stress exposure and damages, neurotoxicity and endocrine disruption are provided. All the sites are characterized by a specific response pattern that allows distinguishing sampling locations. Moreover, these responses are in accordance with data on existing environmental pressures and the chemical analysis of metals performed in surface water. The assessment of individual responses is completed by fish population disturbance monitoring. Based on these measurements, the investigated sites are characterized by different levels of disturbance. This study argues for a multi-parametric approach of aquatic ecosystem contamination based on association between chemical, biochemical and ecological endpoints and provides a testimony of the usefulness of stickleback for this purpose. 相似文献
83.
Kirstin Dow Benjamin K. Haywood Nathan P. Kettle Kirsten Lackstrom 《Regional Environmental Change》2013,13(6):1235-1244
To examine the factors that support adaptation within a regional and sectoral context, this article explores five climate-sensitive sectors in North and South Carolina (Forestry, Government Administration, Tourism, Water Management, and Wildlife Management) and the role of partnerships, collaborations, and networks in facilitating climate adaptation and related activities. Drawing from 117 online questionnaires and interviews with sector leaders across the Carolinas, the article highlights several key functions of networks in regard to supporting adaptation—intra-sector information sharing; monitoring, data collection, and research; and education and outreach. Furthermore, the analysis examines how climate networks in the region have facilitated the development of bonding, bridging, and linking social capital while also noting factors that have constrained the growth and success of both intra- and cross-sector collaboration. Although no formal, or discrete, state or regional cross-sector climate change network exists in the Carolinas, climate adaptations and capacity-building efforts have been supported by ad hoc and decentralized networks, emerging collegial partnerships within and across sectors, and collaborative efforts to pool expertise and resources. The role of different forms of social capital within these networks is discussed in the context of a contentious political environment where support for activities designed to address climate change is limited. These findings enhance our understanding of the social factors and relational processes that shape and influence capacity to adapt to climate change. 相似文献
84.
Benjamin M. Sleeter Tamara S. Wilson Christopher E. Soulard Jinxun Liu 《Environmental monitoring and assessment》2011,173(1-4):251-266
We present the first comprehensive multi-temporal analysis of land-cover change for California across its major ecological regions and primary land-cover types. Recently completed satellite-based estimates of land-cover and land-use change information for large portions of the United States allow for consistent measurement and comparison across heterogeneous landscapes. Landsat data were employed within a pure-panel stratified one-stage cluster sample to estimate and characterize land-cover change for 1973?C2000. Results indicate anthropogenic and natural disturbances, such as forest cutting and fire, were the dominant changes, followed by large fluctuations between agriculture and rangelands. Contrary to common perception, agriculture remained relatively stable over the 27-year period with an estimated loss of 1.0% of agricultural land. The largest net declines occurred in the grasslands/shrubs class at 5,131 km2 and forest class at 4,722 km2. Developed lands increased by 37.6%, composing an estimated 4.2% of the state??s land cover by 2000. 相似文献
85.
86.
Razafimahefa Ravo M. Ludwig-Begall Louisa F. Diallo Mamadou Amadou Dewals Benjamin G. Vanderplasschen Alain Nivelles Olivier Deketelaere Caroline Mauroy Axel Thiry Etienne 《Food and environmental virology》2021,13(4):493-506
Food and Environmental Virology - Human noroviruses impose a considerable health burden globally. Here, a flow cytometry approach designed for their detection in biological waste and food samples... 相似文献
87.
Linking landscape development intensity within watersheds to methyl-mercury accumulation in river sediments 总被引:1,自引:0,他引:1
An indicator of the disturbance of natural systems, the landscape development intensity (LDI) index, was used to assess the potential for land-use within watersheds to influence the production/accumulation of methyl-mercury (MeHg) in river sediments. Sediment samples were collected from locations impacted by well-identified land-use types within the Mobile-Alabama River Basin in Southeastern USA. The samples were analyzed for total-Hg (THg) and MeHg concentrations and the obtained values correlated to the calculated LDI indexes of the sampled watersheds to assess the impact of prevalent land use/land cover on MeHg accumulation in sediments. The results show that unlike THg, levels of MeHg found in sediments are impacted by the LDI indexes. Overall, certain combinations of land-use types within a given watershed appear to be more conducive to MeHg accumulation than others, therefore, pointing to the possibility of targeting land-use practices as potential means for reducing MeHg accumulation in sediments, and ultimately, fish contamination. 相似文献
88.
Numerous studies have focussed on the relationship between female choice and the multiple exaggerated sexual traits of males.
However, little is known about the ability of males to actively enhance specific components of their display in response to
the loss of one component. We investigated the capacity of male satin bowerbirds (Ptilonorhynchus violaceus) to respond to the loss of one of their sexual signals by performing an experiment in which we removed decorations at their
bowers. We found that males compensated for decoration loss by increasing bower construction behaviour and decreasing their
latency to bower painting. These results are novel because they suggest that males can assess the quality of their own display
and make decisions about how to augment their displays. We discuss these results in the context of previous studies of mate
choice in satin bowerbirds, as both of the supplementary behaviours we observed are known correlates of male mating success. 相似文献
89.
90.
D. Alan Hansen Eric S. Edgerton Benjamin E. Hartsell John J. Jansen Navaneethakrishnan Kandasamy 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1460-1471
Abstract This paper presents an overview of a major, long-term program for tropospheric gas and aerosol research in the southeastern United States. Building on three existing ozone (O3)-focused research sites begun in mid-1992, the Southeastern Aerosol Research and Characterization Study (SEARCH) was initiated in mid-1998 as a 7-year observation and research program with a broader focus including aerosols and an expanded geographical coverage in the Southeast. The monitoring network comprises four urban-rural (or urban-suburban) site pairs at locations along the coast of the Gulf of Mexico and inland, including two moderately sized and two major urban areas (Pensacola, FL; Gulfport, MS; Atlanta, GA; and Birmingham, AL). The sites are equipped with an extensive suite of instruments for measuring particulate matter (PM), gases relevant to secondary O3 and the production of secondary aerosol particles, and surface meteorology. The measurements taken to date have added substantially to the knowledge about the temporal behavior and geographic variability of tropospheric aerosols in the Southeast. Details are presented in four papers to follow. 相似文献