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Lynne A. Isbell Dorothy L. Cheney Robert M. Seyfarth 《Behavioral ecology and sociobiology》1990,27(5):351-358
Summary A decline in the density of trees and the deterioration of the habitat of vervet monkeys (Cercopithecus aethiops) in Amboseli National Park, Kenya, have been accompanied by movement of vervet groups into unfamiliar areas. These home range shifts were documented over a period of 26 months. The largest group moved into the home ranges of neighboring groups and acquired more trees, a resource that had become more limited. The groups whose home ranges were encroached upon did not share their home ranges with the intruders, but instead moved into areas that were unoccupied and had a lower density of trees. The largest group was thus more successful than smaller groups in competition for limited resources. For all but one group, movement into new areas was directly associated with the disappearances of female and immature monkeys. Most of the disappearances were attributable to predation. These results suggest that the cost of predation in unfamiliar areas may contribute to the evolution of philopatry in vervets. However, under unstable conditions, resource competition forces these animals to disperse (in groups) despite the high risk of predation.
Offprint requests to: L.A. Isbell 相似文献
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Julia?FischerEmail author Dawn?M.?Kitchen Robert?M.?Seyfarth Dorothy?L.?Cheney 《Behavioral ecology and sociobiology》2004,56(2):140-148
Free-ranging adult male baboons give loud two-syllable wahoo calls during dawn choruses, interactions between groups, when chasing females, and in aggressive interactions with other males. Previous research has shown that the rate and duration of these contest wahoos are correlated with a males competitive ability: high-ranking males call more often, call at faster rates, and call for longer bouts than do low-ranking males. Here we report that acoustic features of wahoos also reveal information about male competitive ability. High-ranking males give wahoos with higher fundamental frequencies (F0) and longer hoo syllables. Within-subject analyses revealed that, as males fall in rank, the hoo syllables tend to shorten within a period of months. As males age and continue to fall in rank, F0 declines, hoo syllables shorten, and formant dispersion decreases. Independent of age and rank, within bouts of calling F0 declines and hoo syllables become shorter. Because wahoos are often given while males are running or leaping through trees, variation in these acoustic features may function as an indicator of a males stamina. The acoustic features of contest wahoos thus potentially allow listeners to assess a males competitive ability.Communicated by C. Nunn 相似文献
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Contamination of aquatic ecosystems with heavy metals has been receiving increased worldwide attention due to their harmful e ects
on human health and other organisms in the environment. Most of the studies dealing with toxic e ects of metals deal with single
metal species, while the aquatic organisms are typically exposed to mixtures of metals. Hence, in order to provide data supporting
the usefulness of freshwater fish as indicators of heavy metal pollution, it has been proposed in the present study to investigate the
bioaccumulation and depuration of chromium in the selected organs of freshwater fingerlings Cirrhinus mrigala, individually and in
binary solutions with nickel. The results show that the kidney is a target organ for chromium accumulation, which implies that it is also
the “critical” organ for toxic symptoms. The results further show that accumulation of nickel in all the tissues of C. mrigala is higher
than that of chromium. In addition, the metal accumulations of the binary mixtures of chromium and nickel are substantially higher
than those of the individual metals, indicating synergistic interactions between the two metals. Theoretically the simplest explanation
for an additive joint action of toxicants in a mixture is that they act in a qualitatively similar way. The observed data suggest that C.
mrigala could be suitable monitoring organisms to study the bioavailability of water-bound metals in freshwater habitats. 相似文献
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RM. Thirupathi R. Ben Ruben Jiju Antony 《International Journal of Sustainable Engineering》2019,12(2):95-107
Application of appropriate environmentally conscious manufacturing strategies enables the sustainable development of products and processes. Automotive component manufacturers recognise the potential of applying appropriate strategies for attaining Triple Bottom Line benefits. In this context, three strategies such as eco-efficiency, waste minimisation and material efficiency are being applied to minimise environmental impacts associated with the manufacture of automotive products and its associated processes. A case study of an automotive component manufacturing firm has been exemplified. After conducting the study, the potential environmental impact was reduced by 20% and eco-efficiency was improved by 13%. Further, improvements have been observed in terms of overall resource consumption and material efficiency. The overall power consumption was reduced by 18% and weight of the component was reduced by 11%. The study aimed at improving the sustainable performance of product by incorporating green and environmentally friendlier manufacturing practices.
Abbreviations: USEPA: United Nations Environmental Protection Agency; OECD: Organisation for Economic Co-operation and Development; WBCSD: World Business Council for Sustainable Development; Eco-QFD: Environmental Quality Function Deployment; WCED: World Commission on Environment and Development; LCA: Life Cycle Assessment 相似文献
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Silk JB Beehner JC Bergman TJ Crockford C Engh AL Moscovice LR Wittig RM Seyfarth RM Cheney DL 《Behavioral ecology and sociobiology》2010,64(11):1733-1747
Analyses of the pattern of associations, social interactions, coalitions, and aggression among chacma baboons (Papio hamadryas ursinus) in the Okavango Delta of Botswana over a 16-year period indicate that adult females form close, equitable, supportive, and
enduring social relationships. They show strong and stable preferences for close kin, particularly their own mothers and daughters.
Females also form strong attachments to unrelated females who are close to their own age and who are likely to be paternal
half-sisters. Although absolute rates of aggression among kin are as high as rates of aggression among nonkin, females are
more tolerant of close relatives than they are of others with whom they have comparable amounts of contact. These findings
complement previous work which indicates that the strength of social bonds enhances the fitness of females in this population
and support findings about the structure and function of social bonds in other primate groups. 相似文献
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Lead is a widespread element and one of the persistent and cumulative pollutants of the environment. The present study deals with the bioaccumulation of lead and the influence of chelating agents, meso 2,3-dimercaptosuccinic acid (DMSA), D-Penicillamine and CaNa2EDTA in reducing the concentration of lead on the selected organs of Catla catla fingerlings for both acute and chronic exposures by using ICP-AES. It is inferred from the present findings that there was a correlation between environmental conditions and the heavy metal contents of the fish. The highest concentration of lead is found in kidney tissues and the lowest in muscle tissues. The accumulation pattern of lead in the selected organs of Catla catla is: kidney > liver > gill > brain > muscle. Also, it has been found that the treatment of chelating agents, DMSA, D-Penicillamine and CaNa2EDTA reduces the concentration of lead significantly for both acute and chronic exposures. The results also show that DMSA is the most effective chelator of lead in reducing the body burden of C. catla fingerlings. The observed data further indicate that C. catla could be suitable for monitoring organisms to study the bioavailability of water-bound metals in freshwater habitats. 相似文献
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Input of trichloroacetic acid into the vegetation of various climate zones--measurements on several continents 总被引:2,自引:0,他引:2
Weissflog L Krüger G Elansky N Putz E Pfennigsdorff A Seyfarth KU Nüchter M Lange C Kotte K 《Chemosphere》2003,52(2):443-449
Trichloroacetic acid (TCA, CCl(3)COOH) is a phytotoxic chemical. Although TCA salts and derivates were once used as herbicides to combat perennial grasses and weeds, they have since been banned because of their indiscriminate herbicidal effects on woody plant species. However, TCA can also be formed in the atmosphere. For instance, the high-volatile C(2)-chlorohydrocarbons tetrachloroethene (TECE, C(2)Cl(4)) and 1,1,1-trichloroethane (TCE, CCl(3)CH(3)) can react under oxidative conditions in the atmosphere to form TCA and other substances. The ongoing industrialisation of Southeast Asia, South Africa and South America means that use of TECE as solvents in the metal and textile industries of these regions in the southern hemisphere can be expected to rise. The increasing emissions of this substance--together with the rise in the atmospheric oxidation potential caused by urban activities, slash and burn agriculture and forest fires in the southern hemisphere--could lead to a greater input/formation of TCA in the vegetation located in the lee of these emission sources. By means of biomonitoring studies, the input/formation of TCA in vegetation was detected at various locations in South America, North America, Africa, and Europe. 相似文献
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T. J. Bergman J. C. Beehner D. L. Cheney R. M. Seyfarth P. L. Whitten 《Behavioral ecology and sociobiology》2006,59(4):480-489
To date, research on testosterone and behavior has focused on individuals, even when studying social behaviors that necessarily
involve multiple participants. Here, we explore male responses to other males of different dominance ranks and testosterone
levels in a population of wild baboons. In chacma baboons (Papio hamadryas ursinus) of the Okavango Delta, a male’s testosterone is related to his rank trajectory and, therefore, the threat he poses to other
males. To examine the effects of testosterone and rank on male–male interactions, we used playback experiments to measure
how a target male responded to the simulated approach of another male, scoring responses by whether or not the subject moved
away from the speaker in the first minute. High testosterone subjects did not move away from the speaker more often than low
testosterone subjects, but high testosterone callers elicited a move more often than low testosterone callers. When the combined
testosterone of the subject and caller was high, moves were most common. The rank relationship between subject and caller
did not predict moves, but the effect of combined testosterone on moving was most pronounced in adjacently ranked males. Adjacently
ranked, high testosterone males are the most likely to be competing for each others’ rank, and our experiments on these dyads
elicited the most moves. Both behavioral and experimental observations indicate that testosterone may be more important than
the rank relationship in predicting the outcome of male–male interactions. Furthermore, combined information on the testosterone
of both males was the best predictor of results, highlighting the utility of dyadic analyses when relating testosterone to
behavior. 相似文献