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671.
Julien G. A. Martin Matthew B. Petelle Daniel T. Blumstein 《Behavioral ecology and sociobiology》2014,68(9):1531-1538
Multiple mating and multiple paternity in polytocous species have been mostly studied from an adaptive (i.e., cost–benefit) perspective. Disease, time, energy, and the risk of injuries are well-known costs of multiple mating, yet from both male and female perspectives, a number of genetic and non-genetic benefits have also been identified. The effects of environmental conditions and individual-specific behavior, however, are much less well understood. Using a long-term study on yellow-bellied marmots (Marmota flaviventris), we evaluated the impacts of environmental variation, social structure, female body mass, and female docility (a personality trait) on the occurrence of multiple paternity. Multiple paternity was influenced by environmental constraints, social constraints, a female’s personality, and her body mass at emergence from hibernation. Personality and mass effects were detected only when environmental or social conditions were favorable. Our results suggest that multiple paternity is mainly limited by the opportunity to have access to multiple mates and is influenced by costs or mate choice because heavier females were more likely to have litters with multiple sires than smaller ones. Future studies in other species might benefit from considering environmental constraints when studying multiple paternity. 相似文献
672.
Yin Qi Daniel W. A. Noble Yayong Wu Martin J. Whiting 《Behavioral ecology and sociobiology》2014,68(12):2035-2042
In lizards, males are predicted to sprint faster and run for longer than females by virtue of higher testosterone levels and differences in morphology. Consequently, escape behaviour is also predicted to be associated with sex and locomotor performance, yet these links have rarely been explored. Here, we tested whether escape behaviour is associated with locomotor performance in the toad-headed agama, Phrynocephalus vlangalii, and whether it is sex-dependent. This species is also characterized by elaborate tail displays, which we examined as a potential pursuit-deterrent signal. Tail waves were performed by a very small proportion (2/58, 3 %) of individuals during predatory trials, suggesting that tail signalling functions exclusively in a social context. To understand the relationships between sex, escape behaviour and performance, we first measured escape behaviour (flight initiation distance, flight distance—measured differently compared to previous studies of lizard escape behaviour, and refuge use) in the field before measuring maximal sprint speed and endurance on the same individuals in the laboratory. Flight initiation distance did not differ between the sexes and was unrelated to performance capacity (maximal endurance and sprint speed) but was positively related to body size with larger individuals fleeing earlier. Males fled farther than females, but flight distance was also unrelated to either endurance or sprint speed. Interestingly, faster females were less likely to enter a refuge than slower females, whereas sprint speed and the probability of taking refuge were unrelated for males. Our results suggest that when males and females are not obviously sexually dimorphic, they are more likely to overlap in escape tactics. 相似文献
673.
Charles Patrick Martin‐Shields 《Disasters》2019,43(3):612-633
Information and communications technology (ICT), primarily mobile telephones and social media, is increasingly important in crisis and disaster response in developing countries. This fact raises an important question: in an information environment that includes traditional media such as radio and television, who are the people that trust information from ICT enough to act on it during a disaster? Drawing on a case study of and original survey data from the island nation of the Independent State of Samoa, this paper yields insights into who uses new technologies, particularly mobile telephones, to make decisions at the local level during crises such as natural disasters, as well as the socio‐political factors that motivate their behaviour. The results add to the growing pool of knowledge on utilisation of ICT and new technologies in developing countries for disaster response, and provide practical information on the social and political factors that lead people to trust different information sources and media. 相似文献
674.
Chloe B. Wardropper Ashley A. Dayer Madeline S. Goebel Victoria Y. Martin 《Conservation biology》2021,35(5):1650-1658
The coronavirus (COVID-19) pandemic is affecting the environment and conservation research in fundamental ways. Many conservation social scientists are now administering survey questionnaires online, but they must do so while ensuring rigor in data collection. Further, they must address a suite of unique challenges, such as the increasing use of mobile devices by participants and avoiding bots or other survey fraud. We reviewed recent literature on online survey methods to examine the state of the field related to online data collection and dissemination. We illustrate the review with examples of key methodological decisions made during a recent national study of people who feed wild birds, in which survey respondents were recruited through an online panel and a sample generated via a project participant list. Conducting surveys online affords new opportunities for participant recruitment, design, and pilot testing. For instance, online survey panels can provide quick access to large and diverse samples of people. Based on the literature review and our own experiences, we suggest that to ensure high-quality online surveys one should account for potential sampling and nonresponse error, design survey instruments for use on multiple devices, test the instrument, and use multiple protocols to identify data quality problems. We also suggest that research funders, journal editors, and policy makers can all play a role in ensuring high-quality survey data are used to inform effective conservation programs and policies. 相似文献
675.
Martin?OlofssonEmail author Sven?Jakobsson Christer?Wiklund 《Behavioral ecology and sociobiology》2012,66(2):209-215
Morphological and behavioural traits can serve as anti-predator defence either by reducing detection or recognition risks,
or by thwarting initiated attacks. The latter defence is secondary and often involves a ‘startle display’ comprising a sudden
release of signals targeting more than one sensory modality. A suggested candidate for employing a multimodal defence is the
peacock butterfly, Inachis io, which, by wing-flicking suddenly, produces sonic and ultrasonic sounds and displays four large eyespots when attacked. The
eyespots make small birds retreat, but whether the sounds produced thwart predator attacks is largely unknown. Peacocks hibernate
as adults in dark wintering sites and employ their secondary defence upon encounter with small rodent predators during this
period. In this study, we staged predator–prey encounters in complete darkness in the laboratory between wild mice, Apodemus flavicollis and Apodemus sylvaticus, and peacocks which had their sound production intact or disabled. Results show that mice were more likely to flee from sound-producing
butterflies than from butterflies which had their sound production disabled. Our study presents experimental evidence that
the peacock butterfly truly employs a multimodal defence with different traits targeting different predator groups; the eyespots
target birds and the sound production targets small rodent predators. 相似文献
676.
Ingo Schlupp Rüdiger Riesch Michael Tobler Martin Plath Jakob Parzefall Manfred Schartl 《Behavioral ecology and sociobiology》2010,64(11):1849-1855
Female choice can often drive the elaboration of male traits, leading to the evolution of secondary sexual traits. In the
Mexican molly, Poecilia sphenops (Poeciliidae), some males exhibit a mustache-like structure on the upper maxilla, the function of which has not been previously
recognized. The mustache consists of epidermal outgrowths at the edge of the scales that appear to have no sensory function.
Trait expression varies within as well as among populations of P. sphenops, but is not linked to male body size polymorphism. In mate choice experiments, female P. sphenops exhibited a visual mating preference for males with mustaches, suggesting that the trait may be sexually selected. Since
the mating behavior of P. sphenops involves contact of the male’s snout and the female genital region prior to copulation, we hypothesize that the mustache
may also convey tactile signals to the female. 相似文献
677.
Robin C. Puett Andrew B. Lawson Allan B. Clark James R. Hebert Martin Kulldorff 《Environmental and Ecological Statistics》2010,17(3):303-316
Many statistical tests have been developed to assess the significance of clusters of disease located around known sources
of environmental contaminants, also known as focused disease clusters. The majority of focused-cluster tests were designed
to detect a particular spatial pattern of clustering, one in which the disease cluster centers around the pollution source
and declines in a radial fashion with distance. However, other spatial patterns of environmentally related disease clusters
are likely given that the spatial dispersion patterns of environmental contaminants, and thus human exposure, depend on a
number of factors (i.e., meteorology and topography). For this study, data were simulated with five different spatial patterns
of disease clusters, reflecting potential pollutant dispersion scenarios: (1) a radial effect decreasing with increasing distance,
(2) a radial effect with a defined peak and decreasing with distance, (3) a simple angular effect, (4) an angular effect decreasing
with increasing distance and (5) an angular effect with a defined peak and decreasing with distance. The power to detect each
type of spatially distributed disease cluster was evaluated using Stone’s Maximum Likelihood Ratio Test, Tango’s Focused Test,
Bithell’s Linear Risk Score Test, and variations of the Lawson–Waller Score Test. Study findings underscore the importance
of considering environmental contaminant dispersion patterns, particularly directional effects, with respect to focused-cluster
test selection in cluster investigations. The effect of extra variation in risk also is considered, although its effect is
not substantial in terms of the power of tests. 相似文献
678.
Thomas Artiss Wesley M. Hochachka Kathy Martin 《Behavioral ecology and sociobiology》1999,46(6):429-434
For several species of birds, high rates of male vigilance are correlated with high rates of female foraging. This relationship
is thought to ultimately result in higher reproductive success for females paired with highly vigilant males. However, previous
research has not examined the behavioural mechanism that produces the correlation between male vigilance and rates of female
foraging. Foraging females may take advantage of vigilance that males are using for other purposes. Alternatively, the purpose
of male vigilance may be to increase females' ability to forage. We examined these alternatives by testing whether vigilance
preceded or followed bouts of female foraging more often than would occur by chance alone, using simultaneous behaviour observations
of pre-incubation pairs of white-tailed ptarmigan (Lagopus leucurus). Our results indicate that each member of a pair may influence the behaviour of the other. Females were more likely to initiate
foraging bouts after males became vigilant than if their mate remained non-vigilant. Moreover, non-vigilant males were more
likely to become vigilant if their mate was foraging than if she was engaged in some other activity. Despite the possibility
that a sexual conflict exists as each member of a pair attempts to maximize its fitness, both sexes behave as though a major
role of male vigilance is to enhance female foraging opportunities.
Received: 3 May 1999 / Received in revised form: 14 June 1999 / Accepted: 16 June 1999 相似文献
679.
Conservation tillage can reduce soil loss; however, the residual herbicides normally used to control weeds are often detected in surface runoff at high levels, particularly if runoff-producing storms occur shortly after application. Therefore, we measured losses of alachlor, atrazine, linuron, and metribuzin from seven small (0.45-0.79-ha) watersheds for 9 yr (1993-2001) to investigate whether a reduced-input system for corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] production with light disking, cultivation, and half-rate herbicide applications could reduce losses compared with chisel and no-till. As a percentage of application, annual losses were highest for all herbicides for no-till and similar for chisel and reduced-input. Atrazine was the most frequently detected herbicide and yearly flow-weighted concentrations exceeded the drinking water standard of 3 microg L(-1) in 20 out of 27 watershed years that it was applied. Averaged for 9 corn yr, yearly flow-weighted atrazine concentrations were 26.3, 9.6, and 8.3 microg L(-1) for no-till, chisel, and reduced-input, respectively. Similarly, flow-weighted concentrations of alachlor exceeded the drinking water standard of 2 microg L(-1) in 23 out of 54 application years and in all treatments. Thus, while banding and half-rate applications as part of a reduced-input management practice reduced herbicide loss, concentrations of some herbicides may still be a concern. For all watersheds, 60 to 99% of herbicide loss was due to the five largest transport events during the 9-yr period. Thus, regardless of tillage practice, a small number of runoff events, usually shortly after herbicide application, dominated herbicide transport. 相似文献
680.
Marta Lisli Giannichi Yoni Gavish Timothy R. Baker Martin Dallimer Guy Ziv 《Conservation biology》2020,34(1):148-157
Offset schemes help avoid or revert habitat loss through protection of existing habitat (avoided deforestation), through the restoration of degraded areas (natural regrowth), or both. The spatial scale of an offset scheme may influence which of these 2 outcomes is favored and is an important aspect of the scheme's design. However, how spatial scale influences the trade-offs between the preservation of existing habitat and restoration of degraded areas is poorly understood. We used the largest forest offset scheme in the world, which is part of the Brazilian Forest Code, to explore how implementation at different spatial scales may affect the outcome in terms of the area of avoided deforestation and area of regrowth. We employed a numerical simulation of trade between buyers (i.e., those who need to offset past deforestation) and sellers (i.e., landowners with exceeding native vegetation) in the Brazilian Amazon to estimate potential avoided deforestation and regrowth at different spatial scales of implementation. Allowing offsets over large spatial scales led to an area of avoided deforestation 12 times greater than regrowth, whereas restricting offsets to small spatial scales led to an area of regrowth twice as large as avoided deforestation. The greatest total area (avoided deforestation and regrowth combined) was conserved when the spatial scale of the scheme was small, especially in locations that were highly deforested. To maximize conservation gains from avoided deforestation and regrowth, the design of the Brazilian forest-offset scheme should focus on restricting the spatial scale in which offsets occur. Such a strategy could help ensure conservation benefits are localized and promote the recovery of degraded areas in the most threatened forest landscapes. 相似文献