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91.
Elise Huchard Alexandra Alvergne Delphine Féjan Leslie A. Knapp Guy Cowlishaw Michel Raymond 《Behavioral ecology and sociobiology》2010,64(5):769-781
In mammals, fathers are facultative caretakers, and male care is expected to evolve only if it is directed towards related
young. Yet, in several promiscuous primate societies, males seem to care for infants despite a presumably low paternity confidence.
In cercopithecines, cohesive associations (‘friendships’) between a lactating female and an adult male are frequent and provide
the female and her infant with protection against various sources of aggression, including infanticide. However, the benefits
gained by males through such relationships remain unclear, in part, because the relatedness between males and their protected
infants has rarely been examined. Moreover, little is known about the nature of the cues underlying kin discrimination by
males in societies where females mate polyandrously. In this study, we combine behavioural and genetic data from wild chacma
baboons (Papio ursinus) in Namibia to investigate (1) whether males are related to their friend’s infant and (2) whether similarity between the
major histocompatibility complex (MHC) genotype of males and infants (potentially perceived through odour phenotype) favours
the establishment of friendships. We first show that males share close genetic ties with their friend’s infants, most often
by having sired the infant. Secondly, we find that male–infant MHC (Class II–DRB) similarity, in contrast to paternity, does not predict male–infant associations. Overall, our results clarify the nature
of the evolutionary benefits gained by males in these heterosexual associations, which can be considered as true paternal
care. However, the proximate mechanisms underlying paternity recognition remain to be identified. 相似文献
92.
Spatio-temporal patterns in the diversity of demersal fish communities off the south coast of South Africa 总被引:3,自引:0,他引:3
The diversity of ecological communities has been the focus of many studies. Because biodiversity provides several indicators
used in an Ecosystem Approach to Fisheries (EAF) to track changes in fish communities, we investigated the spatial and temporal
patterns in the diversity of some demersal fish communities subjected to varying fishing pressure. Depth and catch rate were
the most important predictors in explaining changes in diversity followed by longitude and survey year. Diversity, as measured
by the various indices except for taxonomic distinctness (∆*), initially declined with increasing depth to about a depth of
80 m, then increased to about 150 m after which it declined. Taxonomic distinctness index (∆*) showed an increase in the taxonomic
heterogeneity of the demersal community below the 300-m isobath. Diversity remained relatively constant with increase in longitude
to around 24°E (which has the lowest diversity) after which it increased. The assessment of the temporal trend in diversity
indicates that survey year has a significant effect on all diversity indices except for ∆*. Diversity increased and dominance
declined with time. This may be result of a decline in the abundance of dominant species or an increase in the abundance less
dominant species, or a combination of both effects. Multivariate analysis of the set of diversity indices showed three groups
of indices: those reflecting species richness (S, Margalef’s d), those measuring mainly taxonomic relatedness (∆*), and those balancing the richness and evenness components of diversity
(J′, H′, λ, ∆, Hill’s N1, and Hill’s N2). The relationship between evenness, catch rate, and size was also investigated. Size classes with highest evenness were
found to have lowest catch rate and vice versa. This highlights the need to consider the size and trophic level of species
when linking diversity to the functioning of ecosystems. 相似文献
93.
Robust ways to meet objectives of environmental conservation and social and economic development remain elusive. This struggle may in part be related to insufficient understanding of the feedbacks between conservation initiatives and social-ecological systems, specifically, the ways in which conservation initiatives result in social changes that have secondary effects on the environments targeted by conservation. To explore this idea, we sampled peer-reviewed articles addressing the social and environmental dimensions of conservation and coded each paper according to its research focus and characterization of these feedbacks. The majority of articles in our sample focused either on the effect of conservation initiatives on people (e.g., relocation, employment) or the effect of people on the environment (e.g., fragmentation, conservation efficacy of traditional management systems). Few studies in our sample empirically addressed both the social dynamics resulting from conservation initiatives and subsequent environmental effects. In many cases, one was measured and the other was discussed anecdotally. Among the studies that describe feedbacks between social and environmental variables, there was more evidence of positive (amplifying) feedbacks between social and environmental outcomes (i.e., undesirable social outcomes yielded undesirable environmental effects and desirable social outcomes yielded desirable environmental effects). The major themes within the sampled literature include conflict between humans and wild animals, social movements, adaptive comanagement, loss of traditional management systems, traditional ecological knowledge, human displacement and risks to livelihoods, and conservation and development. The narratives associated with each theme can serve as hypotheses for facilitating further discussion about conservation issues and for catalyzing future studies of the feedbacks between conservation and social-ecological systems. 相似文献
94.
Our disappearing past: a GIS analysis of the vulnerability of coastal archaeological resources in California’s Santa Barbara Channel region 总被引:1,自引:0,他引:1
Leslie A. Reeder Torben C. Rick Jon M. Erlandson 《Journal of Coastal Conservation》2012,16(2):187-197
Coastal archaeological resources around the world often coincide with dense contemporary human populations and a rapidly changing
physical environment. Projected sea level rise and urban expansion during the 21st century threaten to destroy much of our global coastal archaeological heritage. In this study, we adapt an environmental
vulnerability analysis to quantify the threats of modern development and sea level rise on archaeological sites in California’s
Santa Barbara Channel region. Using spatial and statistical techniques, we create a Cultural Resource Vulnerability Index
that combines environmental factors, current and projected urban footprints, and archaeological site positioning. We illustrate
the importance of this method for targeting threatened archaeological sites for mitigation and salvage research. In the process,
we highlight the significance of coastal archaeological sites for helping better understand contemporary environmental and
cultural issues, underscoring the need to preserve or salvage these sites for their significant research value. 相似文献
95.
96.
Jolyon Leslie 《Disasters》1986,10(3):163-171
In December 1982 the central highlands of the Yemen Arab Republic suffered an earthquake that caused extensive damage to traditional buildings in the area. In the aftermath of the relief effort for victims of the disaster, a project was set up to provide local builders with simple information about the means of strengthening homes. This education programme has now been running for almost three years. This report describes the activities of the project, and assesses some of the issues that emerge from this kind of education work, and the methods that have been used. 相似文献
97.
Scott MJ Brandt CA Bunn AL Engel DW Eslinger PW Miley TB Napier BA Prendergast EL Nieves LA 《Environmental management》2005,35(1):84-98
The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks. 相似文献
98.
99.
Timothy J. Barrett Sandra M. Brasfield Leslie C. Carroll Meghan A. Doyle Michael R. van den Heuvel Kelly R. Munkittrick 《Environmental monitoring and assessment》2015,187(5):305
Small-bodied fishes are more commonly being used in environmental effects monitoring (EEM) studies. There is a lack of understanding of the biological characteristics of many small-bodied species, which hinders study designs for monitoring studies. For example, 72 % of fish population surveys in Canada’s EEM program for pulp and paper mills that used small-bodied fishes were conducted outside of the reproductive period of the species. This resulted in an inadequate assessment of the EEM program’s primary effect endpoint (reproduction) for these studies. The present study examined seasonal changes in liver size, gonad size, and condition in seven freshwater and estuarine small-bodied fishes in Atlantic Canada. These data were used to examine differences in reproductive strategies and patterns of energy storage among species. Female gonadal recrudescence in all seven species began primarily in the 2-month period in the spring before spawning. Male gonadal development was concurrent with females in five species; however, gonadal recrudescence began in the fall in male three-spined stickleback (Gasterosteus aculeatus) and slimy sculpin (Cottus cognatus). The spawning period for each species was estimated from the decline in relative ovary size after its seasonal maximum value in spring. The duration of the spawning period reflected the reproductive strategy (single vs multiple spawning) of the species. Optimal sampling periods to assess reproductive impacts in each species were determined based on seasonal changes in ovary size and were identified to be during the prespawning period when gonads are developing and variability in relative gonad size is at a minimum. 相似文献
100.