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911.
Kenneth J. Howard Philip M. Johns Nancy L. Breisch Barbara L. Thorne 《Behavioral ecology and sociobiology》2013,67(10):1575-1585
In many termite taxa, colonies occupying the same nesting resource can meet, interact, and merge with unrelated conspecific neighbors. Because proto-termite ancestors likely also co-inhabited resources and experienced interactions with neighboring conspecific families, extant species that form fused colony units may offer fundamental clues to explaining the origins of eusociality in Isoptera, particularly if both original families retain the potential for reproduction. We allowed entire colonies of Zootermopsis nevadensis (Archotermopsidae) to interact, merge, and develop in the lab, then used genetic markers to determine the family of origin of reproductives, soldiers, and helpers. Persisting and new members of all castes arose from both original colonies and in some cases were hybrids of the two original lineages. We also measured the frequency of mixed-family colonies in natural settings. Ten out of 30 field sampled colonies contained mixed families, demonstrating that interactions and fusions are common in nature. We discuss the implications of our findings as a model system for understanding the evolution of eusociality in termites, highlighting the importance of ecological circumstances impacting direct, indirect, and colony-level fitness. 相似文献
912.
Lesley Rickards Juan Brown Angela Hibbert Philip Woodworth Andrew J. Plater 《Journal of Coastal Conservation》2013,17(3):691-693
In this Comment we refer to our strong reservations concerning the paper by Powell et al. J Coast Conserv, (2012) recently published on the Online First web site of the Journal of Coastal Conservation. The paper makes a number of comments on data obtained from the Permanent Service for Mean Sea Level (PSMSL) and British Oceanographic Data Centre (BODC) which are incorrect or misleading. In addition, some of their comments on sea-level science in general need to be challenged and corrected. 相似文献
913.
Michael P. Harris Francis Daunt Maria I. Bogdanova José J. Lahoz-Monfort Mark A. Newell Richard A. Phillips Sarah Wanless 《Marine Biology》2013,160(11):2877-2889
Miniature geolocator loggers (Global Location Sensing, GLS) that provide daily locations of birds have revolutionised the study of winter ecology and migration patterns of seabirds. A long-term study of ringing recoveries and analyses of heavy metals and pollutants in tissues of Atlantic puffins Fratercula arctica from the Isle of May, south-east Scotland, suggested that this population wintered mainly within the North Sea. However, deployment of GLS devices over the 2007/2008 winter showed that many breeding birds made major excursions into the east Atlantic. This winter was the second of two when survival was extremely low (survival in 2006/2007 and 2007/2008 was 0.696 and 0.695, respectively, compared to the average of 0.922 over the period 1984/1985–2005/2006). These low rates of survival suggested that the unexpected use of the Atlantic might have been associated with unusually poor conditions in the North Sea as indicated by very low breeding success in 2007. Survival rate returned to previous levels in 2008/2009 providing the opportunity to test whether higher survival was associated with birds remaining in the North Sea, or whether movements into the Atlantic are a feature of this population unrelated to survival. Accordingly, geolocators were deployed over the 2009/2010 winter when adult survival was subsequently established to be high (0.913). We found greater support for the hypothesis that winter distribution is not associated with survival. Thus, 8 (40 %) of 20 individuals followed in 2009/2010 went into the Atlantic, a rate not significantly different from 11 (58 %) of the 19 followed in the 2007/2008 winter. Indeed, birds actually spent longer in the Atlantic and used a wider variety of areas in 2009/2010, although the time spent away from the colony was significantly shorter than in 2007/2008. Since our data were from individuals that survived, remaining in or moving out of the North Sea can both be successful strategies during winters when the population as a whole shows either high or low survival rates. Unfortunately, we do not know where birds that died had gone, and hence, the relative survival of birds that did or did not move into the Atlantic. Determining the link between survival and wintering area for any seabird remains a formidable challenge and will have to await the development of technologies that can determine both where and when birds die. 相似文献
914.
915.
Most studies examining escape behaviour have considered single approaches and single fleeing responses; few have considered how organisms’ response is influenced by persistent pursuit. We explored fleeing behaviour of two grasshopper species to test whether they modified escape behaviour when approached repeatedly. Schistocerca alutacea did not increase flight initiation distance (FID) upon repeated approach but fled farther. Psinidia fenestralis increased its FID on the second approach but decreased its flight distance over successive escapes. Both species showed a bimodal pattern of flight direction, either flying directly away or flying perpendicular to the direction of the observer’s approach. Neither species showed a significant pattern of flight direction or change in flight direction with successive escapes. Most (88 %) P. fenestralis initially landed on sand, but after repeated approaches an increasing proportion landed in grass and hid. Both species therefore changed escape behaviour with persistent pursuit but used different tactics, suiting their flight ability or camouflage, and optimised habitat use. Three grasshopper species have now been examined for responses to repeated approach by predators and all show different tactics supporting escape decision theory. Our results emphasise the variety of escape responses across species and how the dynamic nature of escape responses vary according to an animal’s situation. Rather than single optimum escape options, each grasshopper species shows a range of responses, which vary with risk from persistent predators. Although grasshoppers provide an excellent model, it would be profitable to examine responses of a range of species according to levels of predation risk. 相似文献
916.
Rajasekharan Reshmy Bahuleyan Arun Karthika Madhavan Aravind Philip Eapen Sindhu Raveendran Binod Parameswaran Kumar Awasthi Mukesh Pandey Ashok 《Environmental science and pollution research international》2023,30(4):8977-8986
Environmental Science and Pollution Research - The use of jackfruit peel as a source for natural and fully biodegradable “nanocellulose” (NC) for the production of bioplastics with... 相似文献
917.
Louise Mair Eduardo Amorim Monira Bicalho Thomas M. Brooks Vincente Calfo Renata de T. Capellão Colin Clubbe Marianne Evju Eduardo P. Fernandez Gláucia C. Ferreira Frank Hawkins Randall R. Jiménez Lucas S. B. Jordão Magni Olsen Kyrkjeeide Nicholas B. W. Macfarlane Bianca C. Mattos Pablo H. A. de Melo Lara M. Monteiro Eimear Nic Lughadha Nina Pougy Domitilla C. Raimondo Trine Hay Setsaas Xiaoli Shen Marinez Ferreira de Siqueira Bernardo B. N. Strassburg Philip J. K. McGowan 《Conservation biology》2023,37(1):e14046
The successful implementation of the Convention on Biological Diversity's post-2020 Global Biodiversity Framework will rely on effective translation of targets from global to national level and increased engagement across diverse sectors of society. Species conservation targets require policy support measures that can be applied to a diversity of taxonomic groups, that link action targets to outcome goals, and that can be applied to both global and national data sets to account for national context, which the species threat abatement and restoration (STAR) metric does. To test the flexibility of STAR, we applied the metric to vascular plants listed on national red lists of Brazil, Norway, and South Africa. The STAR metric uses data on species’ extinction risk, distributions, and threats, which we obtained from national red lists to quantify the contribution that threat abatement and habitat restoration activities could make to reducing species’ extinction risk. Across all 3 countries, the greatest opportunity for reducing plant species’ extinction risk was from abating threats from agricultural activities, which could reduce species’ extinction risk by 54% in Norway, 36% in South Africa, and 29% in Brazil. Species extinction risk could be reduced by a further 21% in South Africa by abating threats from invasive species and by 21% in Brazil by abating threats from urban expansion. Even with different approaches to red-listing among countries, the STAR metric yielded informative results that identified where the greatest conservation gains could be made for species through threat-abatement and restoration activities. Quantifiably linking local taxonomic coverage and data collection to global processes with STAR would allow national target setting to align with global targets and enable state and nonstate actors to measure and report on their potential contributions to species conservation. 相似文献
918.
Khandelwal Kapil Nanda Sonil Boahene Philip Dalai Ajay K. 《Environmental Chemistry Letters》2023,21(5):2619-2638
Environmental Chemistry Letters - The rising issues of global warming due to the rapid use of fossil fuels are calling for sustainable energies such as dihydrogen, thereafter named... 相似文献
919.
The fate of manure nutrients in beef cattle (Bos taurus) feedlots is influenced by handling treatment, yet few data are available in western Canada comparing traditional practices (fresh handling, stockpiling) with newer ones (composting). This study examined the influence of handling treatment (fresh, stockpiled, or composted) on nutrient levels and mass balance estimates of feedlot manure at Lethbridge, Alberta, and Brandon, Manitoba. Total carbon (TC) concentration of compost (161 kg Mg(-1)) was lower (P < 0.001) than stockpiled (248 kg Mg(-1)), which was in turn lower (P < 0.001) than fresh manure (314 kg Mg(-1)). Total nitrogen (TN) concentration was not affected by handling treatment while total phosphorus (TP) concentration increased with composting at Lethbridge. The percent inorganic nitrogen (PIN) was lower (P < 0.01) for compost (5.1%) than both fresh (24.7%) and stockpiled (28.9%) manure. Composting led to higher (P < 0.05) dry matter (DM) losses (39.8%) compared to stockpiling (22.5%) and higher (P < 0.05) total mass (water + DM) losses (65.6 vs. 35.2%). Carbon (C) losses were higher (P < 0.01) with composting (66.9% of initial) than with stockpiling (37.5%), as were nitrogen (N) losses (46.3 vs. 22.5%, P < 0.05). Composting allowed transport of two times as much P as fresh manure and 1.4 times as much P as stockpiled manure (P < 0.001) on an "as is" basis. Our study looked at one aspect of manure management (i.e., handling treatment effects on nutrient concentrations and mass balance estimates) and, as such, should be viewed as one component in the larger context of a life cycle assessment. 相似文献
920.
Andrzej Bytnerowicz Dan Cayan Philip Riggan Susan Schilling Philip Dawson Mary Tyree Lynn Wolden Robert Tissell Haiganoush Preisler 《Atmospheric environment (Oxford, England : 1994)》2010,44(5):678-687
Combustion emissions and strong Santa Ana winds had pronounced effects on patterns and levels of ambient ozone (O3) in southern California during the extensive wildland fires of October 2007. These changes are described in detail for a rural receptor site, the Santa Margarita Ecological Reserve, located among large fires in San Diego and Orange counties. In addition, O3 changes are also described for several other air quality monitoring sites in the general area of the fires. During the first phase of the fires, strong, dry and hot northeasterly Santa Ana winds brought into the area clean continental air masses, which resulted in minimal diurnal O3 fluctuations and a 72-h average concentration of 36.8 ppb. During the second phase of the fires, without Santa Ana winds present and air filled with smoke, daytime O3 concentrations steadily increased and reached 95.2 ppb while the lowest nighttime levels returned to ~0 ppb. During that period the 8-h daytime average O3 concentration reached 78.3 ppb, which exceeded the federal standard of 75 ppb. After six days of fires, O3 diurnal concentrations returned to pre-fire patterns and levels. 相似文献