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31.
Jutta Gutberlet 《Waste management (New York, N.Y.)》2010,30(2):171-173
32.
Assisting the genetic parents in the rearing of young, a widespread phenomenon in many birds and mammals, is usually regarded
as an altruistic or mutualistic behavior. Infant handling by females other than the mother is also common in many primates,
but due to high within- and between-species variation and limited knowledge about fitness consequences there is no consensus
about its evolutionary and functional significance. Analysis of female infant-handling patterns and its reproductive consequences
in three groups of semifree-ranging Barbary macaques revealed that nulliparous females significantly more often handled infants
than parous females, but infant handling experience did not affect survival of their own first live-born offspring. Females
interacted preferentially with closely related infants, but infant handling frequency improved neither infant survival nor
maternal fecundity. Reciprocation of infant handling by mothers was rare. Although “aunting to death” occurred in the population,
the hypothesis that infant handling serves to reduce the fitness of competitors was not supported. Limited evidence suggests
that females at least sometimes use infants as strategic tools in the course of alliance formation. In concert with this poor
evidence for a functional basis of the behavior, several lines of evidence support the hypothesis that infant handling evolved
as a non-adaptive by-product of a strong selection for mother-offspring bonding. (1) Rates of infant handling were highest
among females that experienced early infant loss. (2) Females caring for infants or yearlings of their own handled other infants
significantly less often than females without dependent offspring. (3) Infant handling by females was most prevalent during
the infants’ first month of life. (4) Both “aunting to death” and a successful adoption occurred irrespective of kinship relations.
Although the by-product hypothesis appears to be the only one able to explain all results of this study, the apparent rarity
of infant handling in non-female-bonded species suggest that kin selection is a possible alternative explanation for the evolution
of female infant-handling in primates.
Received: 30 December 1995/Accepted after revision: 10 May 1996 相似文献
33.
Jeffrey G. Holmquist Jutta Schmidt-Gengenbach Sylvia A. Haultain 《Environmental management》2013,52(6):1474-1486
Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass (Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat (Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage. 相似文献
34.
In a field study, soils of four conventional free-range and organic broiler runs were analyzed for N and P concentrations in the years 2000 and 2001. Zones of different use intensity by broilers were identified on the free runs and mean zonal nutrient contents were compared with each other. Intensity of use by birds and spatial distribution of soil nutrient concentrations were found to be related to each other. Fecal N input by broilers resulted in accumulation of soil mineral nitrogen (N(min)) contents down to a 90-cm sampling depth. In highly frequented "hot spots," plant requirement as defined by the German "N-Basis-Sollwert" (110 kg/ha N(min)) for grassland was exceeded in all four cases. This implies an increased environmental risk of ammonia volatilization and nitrate leaching. Fecal P input by broilers resulted in accumulation of plant-available and thus mobile soil P (phosphorus extracted with calcium-acetate-lactate [P(CAL)] and phosphorus extracted with water [P(w)]) in the most intensely used zones. In these areas, soil P contents exceeded 90 mg/kg P(CAL) (upper limit of soil test P defined in Germany for optimum plant yield) by as much as 217 mg/kg, which indicates an enhanced risk of P loss from the soil via runoff or leaching. The conclusion might be drawn that, with regard to nutrient loss from free-run soils, intensive indoor production in a closed system may be more environmentally neutral than conventional free-range or organic production. However, to put this into perspective, the scope of the environmental risk connected with spatially limited point accumulation of nutrients should be considered. Furthermore, an environmental evaluation must also account for the fate and environmental effects of the broiler litter produced inside the broiler house. 相似文献
35.
36.
Recent investigations have indicated that animals are able to use chemical cues of predators to assess the magnitude of predation
risk. One possible source of such cues is predator diet. Chemical cues may also be important in the development of antipredator
behaviour, especially in animals that possess chemical alarm substances. Tadpoles of the common toad (Bufo bufo) are unpalatable to most vertebrate predators and have an alarm substance. Tadpoles of the common frog (Rana temporaria) lack both these characters. We experimentally studied how predator diet, previous experience of predators and body size
affect antipredator behaviour in these two tadpole species. Late-instar larvae of the dragonfly Aeshna juncea were used as predators. The dragonfly larvae were fed a diet exclusively of insects, R. temporaria tadpoles or B. bufo tadpoles. R. temporaria tadpoles modified their behaviour according to the perceived predation risk. Depending on predator diet, the tadpoles responded
with weak antipredatory behaviour (triggered by insect-fed predators) or strong behaviour (triggered by tadpole-fed predators)
with distinct spatial avoidance and lowered activity level. The behaviour of B. bufo in predator diet treatments was indistinguishable from that in the control treatment. This lack of antipredator behaviour
is probably related to the effective post-encounter defenses and more intense competitive regime experienced by B. bufo. The behaviour of both tadpole species was dependent on body size, but this was not related to predator treatments. Our results
also indicate that antipredator behaviour is largely innate in tadpoles of both species and is not modified by a brief exposure
to predators.
Received: 22 August 1996 / Accepted after revision: 31 January 1997 相似文献
37.
Summary In the course of a long-term study on social organization of semi-free-ranging Barbary macaques (Macaca sylvanus) at Affenberg Salem, genealogical and cross-genealogical rank relations of adult and adolescent females in three social groups were studied. Female rank was highly dependent on maternal rank, but the process of rank acquisition was also affected by age/size differences between members of different families. Mother-daughter rank reversal was rare, but all old, postreproductive matriarchs were outranked by their adult daughters. Contrary to findings of other studies on macaques, younger sisters seldom outranked older sisters. There was no genealogy with a strict age-inversed hierarchy among adult sisters as described for rhesus and Japanese macaques. Rank reversals between sisters were more frequent in genealogies with old or dead matriarchs, in large clans, and in dyads with an age difference of more than 1 year, indicating that demographic variables influence intra-genealogical dominance relations. It is suggested that close, long-lasting relationships between sisters and mothers and doughters impede rank reversals. Previous evolutionary models of female dominance relations in primates that explain rank relations among sisters as a function of their reproductive value or as a strategy of the mother to maintain her own status are not supported by the data. The results of this and other studies indicate that rank reversal between sisters is not as universal for Old World monkeys, or even macaques, as frequently proposed. 相似文献
38.
Summary New data on the secondary sex ratio in semi-free-ranging Barbary macaques at Salem confirm the observation that the offspring of high-ranking females in this colony are biased towards sons while the offspring of low-ranking females are biased towards daughters. Analysis of interbirth intervals yielded no consistent differences in the relative costs of rearing male and female offspring for either high- or low-ranking females. Survivorship to adulthood of male and female offspring born to mothers of all rank classes was remarkably high, and there was no indication that juvenile females of low-ranking mothers face any greater risk. Daughters of high- and low-ranking mothers showed no substantial differences in reproductive success, while mating and probably reproductive success of sons seemed to be dependent on maternal rank, at least at the beginning of their reproductive career. The results suggest that variation in sex ratio does increase parental fitness.
Offprint requests to: A. Paul 相似文献
39.
Jutta Haider 《Environmental Communication: A Journal of Nature and Culture》2016,10(4):473-491
This article studies environmental information as it circulates in social media, specifically in personal blogs and microblogs. It rests on a thematic analysis of a selection of Swedish language, personal, everyday life environment blogs active during 2011 and 2012 and the social media applications connected to these blogs. Gibson's concept of affordances and Foucault's notion of governmentality are brought together to examine how material and technological affordances of social media and the structures of governmentality work together to engender a type of information on environmentally friendly living that is rooted in the conditions of the Web, together with a view of society which is structured around choice and individual responsibility. The article argues that information is woven into the texture of the social on every level, including everyday life practices, and hence social media, as tools in such practices, contribute to shaping the way in which information on environmentally friendly living is articulated, shaped, and filled with meaning. 相似文献
40.
Jutta Geldermann Robert Gabriel Otto Rentz 《Environmental science and pollution research international》1999,6(2):115-121
The burning of kerosene in jet turbines is investigated for two reference flights with a Boeing 747-400 and an Airbus A320-200,
representing the typical Lufthansa planes for long and middle distance. The ecological evaluation is performed by Life Cycle
Assessment (LCA). Formation of condensation trails, which is a specific environmental impact caused by air traffic, has to
be considered in addition to established LCA impact categories. Based on the ecological assessment, an improvement assessment
is performed. Environmental performance of diesel fuel during the combustion in car engines is analysed based on available
publications. The relevant parameters for the environmental impact of the combustion of diesel (aromatics content, reduction
of sulphur content, the reduction of the density and raising of the cetane number) are discussed with regard to improvements
of the exhaust qualities of kerosene. A reduction of the aromatics content promises to improve the emission of soot which
should be further investigated. 相似文献