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991.
Daniel Aguilera-Olivares Camila Burgos-Lefimil Wara Melendez Luis Flores-Prado Hermann M. Niemeyer 《Chemoecology》2016,26(5):163-172
Nestmate recognition is a necessary capacity for the occurrence of discrimination between nestmate and non-nestmate individuals. In one-piece nesting termites, which nest and forage in a single piece of wood, nestmate recognition is poorly studied mainly because the probability of encountering exogenous individuals is low in comparison with separate-piece nesting termites. Previous work described that production of soldiers of Neotermes chilensis, a one-piece nesting termite, increased when the risk of invasion of their colony increased, for example when neighboring colonies were present in the same nesting substrate and members of different colonies met when digging galleries. If soldiers are to fulfill their defensive role under these circumstances, they should show nestmate recognition ability; moreover, based on work on other social insects, such nestmate recognition should be based on cuticular compounds (CC). Bioassays were performed in which a soldier of N. chilensis was confronted with a nestmate or non-nestmate primary reproductive, pseudergate or another soldier, and in which a soldier was confronted with untreated and with CC-deprived dead primary reproductives. The results showed that soldiers were indeed more aggressive toward non-nestmates than nestmates for all castes, and that this discrimination was mediated mainly by qualitative (simple matching coefficient) and quantitative (Renkonen index) differences in CC. 相似文献
992.
993.
Benjamin F. Clark Joshua J. Amiel Richard Shine Daniel W. A. Noble Martin J. Whiting 《Behavioral ecology and sociobiology》2014,68(2):239-247
The ability of an animal to acquire, process and learn from information in their environment is thought to be fundamental to fitness. We currently have a poor understanding of the learning ability of young animals within the first few months of their life, the types of learning they use and the extent of their learning ability. Furthermore, an animal’s developmental environment, such as nest incubation temperature, may profoundly influence motor and cognitive skills. We first tested the ability of hatchling three-lined skinks (Bassiana duperreyi) incubated at ‘hot’ and ‘cold’ temperatures to solve an instrumental (motor) task before assessing their ability to learn colour associations in a multi-stage instrumental task, with a choice reversal. While 53 (88.3 %) lizards successfully completed the training phase, 14 (46.7 %) of the ‘hot’ incubated and none of the ‘cold’ incubated lizards successfully completed the instrumental task. Thirteen of these lizards rapidly learnt to discriminate colours, and this culminated in eight individuals successfully completing a choice reversal. Hatchling B. duperreyi demonstrated surprisingly rapid learning, and these results highlight the potentially important role of cognition during development and ultimately, in fitness. 相似文献
994.
Animals adopt different strategies to communicate by means of sound in noisy environments. Some animals increase, while others decrease, their vocal activity in the presence of interference. Anuran amphibians from diverse latitudes exhibit both kinds of responses. Recent studies have shown that males of Batrachyla taeniata and Batrachyla antartandica from the temperate austral forest do not call in response to the presentation of advertisement calls of sympatric congeneric species, but their responsiveness to other kinds of interference has not been tested. To explore the diversity in responsiveness to acoustic intrusion in a single species, we exposed males of B. taeniata to prolonged prerecorded natural abiotic noises of wind, creek, and rain and to a band-pass noise centered at 2,000 Hz, at 67 dB sound pressure level (SPL). The subjects drastically increased their call rate when exposed to all four sounds. Frogs also responded by augmenting their vocal activity to exposures of band-pass noise at increasing intensities (55–79 dB SPL). The increase in vocal activity in response to noise is strong relative to those of other anurans from the temperate forest studied previously under similar exposures. These results reveal a remarkable activation of vocal response to acoustic interference of continuous abiotic noise, which would allow compensating for limitations in the active communication space under background sounds. This strategy contrasts with the decrease in vocal output amid interference from heterospecific signals reported formerly for this frog, a tactic that would restrict energy expenditure to relevant acoustic competition with conspecifics. 相似文献
995.
Political drivers of epidemic response: foreign healthcare workers and the 2014 Ebola outbreak 下载免费PDF全文
This study demonstrates that countries responded quite differently to calls for healthcare workers (HCWs) during the Ebola epidemic in West Africa in 2014. Using a new dataset on the scale and timing of national pledges and the deployment of HCWs to states experiencing outbreaks of the virus disease (principally, Guinea, Liberia, and Sierra Leone), it shows that few foreign nations deployed HCWs early, some made pledges but then fulfilled them slowly, and most sent no HCWs at all. To aid understanding of such national responses, the paper reviews five theoretical perspectives that offer potentially competing or complementary explanations of foreign government medical assistance for international public health emergencies. The study systematically validates that countries varied greatly in whether and when they addressed HCW deployment needs during the Ebola crisis of 2014, and offers suggestions for a theory‐driven inquiry to elucidate the logics of foreign interventions in critical infectious disease epidemics. 相似文献
996.
Kyle G. Horton Benjamin M. Van Doren Heidi J. Albers Andrew Farnsworth Daniel Sheldon 《Conservation biology》2021,35(6):1777-1786
Near-term ecological forecasting has the potential to mitigate negative impacts of human modifications on wildlife by directing efficient action through relevant and timely predictions. We used the U.S. avian migration system to highlight ecological forecasting applications for aeroconservation. We used millions of observations from 143 weather surveillance radars to construct and evaluate a migration forecasting system for nocturnal bird migration over the contiguous United States. We identified the number of nights of mitigation required to reduce the risk of aerial hazards to 50% of avian migrants passing a given area in spring and autumn based on dynamic forecasts of migration activity. We also investigated an alternative approach, that is, employing a fixed conservation strategy based on time windows that historically capture 50% of migratory passage. In practice, during both spring and autumn, dynamic forecasts required fewer action nights compared with fixed window selection at all locations (spring: mean of 7.3 more alert days; fall: mean of 12.8 more alert days). This pattern resulted in part from the pulsed nature of bird migration captured in the radar data, where the majority (54.3%) of birds move on 10% of a migration season's nights. Our results highlight the benefits of near-term ecological forecasting and the potential advantages of dynamic mitigation strategies over static ones, especially in the face of increasing risks to migrating birds from light pollution, wind energy infrastructure, and collisions with structures. 相似文献
997.
Despite broad scientific consensus that sustainable use of wildlife can enhance conservation efforts, ethical concerns have led some community groups to oppose use of wild animals. Voicing those concerns is legitimate, but underlying philosophical bias should not influence science-based analysis and interpretation. We argue that philosophical biases are common in the scientific literature on trade in wildlife. The critically important case of bias surrounding the use of reptile leathers for luxury fashion illustrates the problem. Based on analysis of official seizures of fashion products made from wildlife, a recent study inferred that criminal activity (as inferred by noncompliance with regulations) was common and increasing and, hence, that authorities needed to adopt more stringent restrictions on the trade. In fact, the conclusions of that study are artifacts of pseudoreplication (e.g., multiple counts of single violations) and biased sampling (e.g., focus on companies with high rates of error) and run directly opposite to actual patterns in the data. As a proportion of overall trade, rates of noncompliance are exceptionally low (<0.4%), are declining, and result primarily from paper-work errors rather than criminal intent (e.g., such errors are more frequent for goods shipped by government authorities than by the commercial fashion industry). The recommendation by the study authors to prohibit the international trade in wildlife-based fashion products is imperiling a sustainable trade that can benefit biodiversity and people's livelihoods by providing financial incentives for conservation of species and habitats. This example offers a warning of the dangers of basing research on the wildlife trade on ethical or philosophical positions rather than objective evaluations of evidence. 相似文献
998.
Laura Thomas-Walters Amy Hinsley Daniel Bergin Gayle Burgess Hunter Doughty Sara Eppel Douglas MacFarlane Wander Meijer Tien Ming Lee Jacob Phelps Robert J. Smith Anita K. Y. Wan Diogo Veríssimo 《Conservation biology》2021,35(2):483-491
The dominant approach to combating the illegal wildlife trade has traditionally been to restrict the supply of wildlife products. Yet conservationists increasingly recognize the importance of implementing demand-side interventions that target the end consumers in the trade chain. Their aim is to curb the consumption of wildlife or shift consumption to more sustainable alternatives. However, there are still considerable knowledge gaps in understanding of the diversity of consumer motivations in the context of illegal wildlife trade, which includes hundreds of thousands of species, different uses, and diverse contexts. Based on consultation with multiple experts from a diversity of backgrounds, nationalities, and focal taxa, we developed a typology of common motivations held by wildlife consumers that can be used to inform conservation interventions. We identified 5 main motivational categories for wildlife use: experiential, social, functional, financial, and spiritual, each containing subcategories. This framework is intended to facilitate the segmentation of consumers based on psychographics and allow the tailoring of interventions—whether behavior change campaigns, enforcement efforts, or incentive programs—to the specific context in which they will be used. Underlining the importance of consumer research and collaborating with local actors is an important step toward promoting a more systematic approach to the design of demand reduction interventions. 相似文献
999.
Paul M. Bradley Celeste A. Journey Julie D. Kirshtein Mary A. Voytek Pierre J. Lacombe Thomas E. Imbrigiotta Francis H. Chapelle Claire J. Tiedeman Daniel J. Goode 《补救:环境净化治理成本、技术与工艺杂志》2012,22(2):21-32
Significant microbial reductive dechlorination of [1,2 14C] cis‐dichloroethene (DCE) was observed in anoxic microcosms prepared with unamended, fractured rock aquifer materials, which were colonized in situ at multiple depths in two boreholes at the Naval Air Warfare Center (NAWC) in West Trenton, New Jersey. The lack of significant reductive dechlorination in corresponding water‐only treatments indicated that chlororespiration activity in unamended, fractured rock treatments was primarily associated with colonized core material. In these unamended fractured rock microcosms, activity was highest in the shallow zones and generally decreased with increasing depth. Electron‐donor amendment (biostimulation) enhanced chlororespiration in some but not all treatments. In contrast, combining electron‐donor amendment with KB1 amendment (bioaugmentation) enhanced chlororespiration in all treatments and substantially reduced the variability in chlororespiration activity both within and between treatments. These results indicate (1) that a potential for chlororespiration‐based bioremediation exists at NAWC Trenton but is limited under nonengineered conditions, (2) that the limitation on chlororespiration activity is not entirely due to electron‐donor availability, and (3) that a bioaugmentation approach can substantially enhance in situ bioremediation if the requisite amendments can be adequately distributed throughout the fractured rock matrix. © 2012 Wiley Periodicals, Inc.* 相似文献
1000.
The addition of extraneous devices (such as night vision goggles) to the helmet assembly has created a new safety hazard for the aviator. The additional mass and misplaced center of gravity (cg) associated with these devices poses the threat of neck injury during ejection, windblast, parachute opening, and other high-G maneuvers. Computer biodynamic simulations using the Articulated Total Body model shows that additional mass has very little effect on head injury scales, head/neck torques, and flexion angles. On the other hand, any combination of cg offset or initial head rest position that causes the head/helmet assembly cg to be anterior of the head/neck joint results in significant head rotation, head torques, and head injury scale values. 相似文献