Search results for "SUCCESS"
showing 10 items of 983 documents
Investigating the influence of climate changes on rodent communities at a regional-scale (MIS 1-3, southwestern France).
2016
25 pages; International audience; Terrestrial ecosystems have continuously evolved throughout the Late Pleistocene and theHolocene, deeply affected by both progressive environmental and climatic modifications, aswell as by abrupt and large climatic changes such as the Heinrich or Dansgaard-Oeschgerevents. Yet, the impacts of these different events on terrestrial mammalian communities arepoorly known, as is the role played by potential refugia on geographical species distributions.This study examines community changes in rodents of southwestern France between50 and 10 ky BP by integrating 94 dated faunal assemblages coming from 37 archaeologicalsites. This work reveals that faunal distributi…
Height predicts jealousy differently for men and women
2008
Because male height is associated with attractiveness, dominance, and reproductive success, taller men may be less jealous. And because female height has a curvilinear relationship with health and reproductive success (with average-height females having the advantages), female height may have a curvilinear relationship with jealousy. In Study 1, male height was found to be negatively correlated with self-reported global jealousy, whereas female height was curvilinearly related to jealousy, with average-height women reporting the lowest levels of jealousy. In Study 2, male height was found to be negatively correlated with jealousy in response to socially influential, physically dominant, and…
Variation in Great Tit Nest Mass and Composition and Its Breeding Consequences: A Comparative Study in four Mediterranean Habitats
2013
Bird nests are structures whose properties affect breeding performance. Thus, the vast majority of bird species build their own characteristic nests, selecting appropriate materials to do so. However, in habitats where the availability of "ideal" materials is low, some ability to use alternative ones would be necessary, even at the cost of having breeding success reduced. The Great Tit (Parus major) breeds under widely different environmental conditions. Its nests are althought to be composed mainly of moss, although very few studies have quantified nest composition. Our target here was describing Great Tit nest mass and composition in four different Mediterranean habitats, and exploring th…
Across and Within-Forest Effects on Breeding Success in Mediterranean Great TitsParus major
2010
Forest type and habitat structure can have profound effects on different aspects of avian life histories. These effects may, however, strongly differ across and within forests that vary in vegetation composition and structure, especially when an ancient forest has been replaced by a new forest. To test for these differences in effect, we studied Great Tit Parus major life-history traits (280 first clutches) in two Mediterranean evergreen forests during 2005–07: an ancient Holm Oak Quercus ilex and a reforested pine forest. A comparison between forests revealed that females breeding in the Holm Oak forest started laying one week later, and produced larger clutches and broods both at hatching…
Nestling growth and mortality of Pied Flycatchers Ficedula hypoleuca in relation to weather and breeding effort
1996
The growth pattern and mortality of young Pied Flycatchers Ficedula hypoleuca were studied to focus on the mechanisms and constraints behind the widely studied optimization of clutch size. The clutch sizes were modified, and the growth and survival of chicks from different clutch sizes were monitored along with the prevailing weather during the nestling period to detect the effect of weather on reproductive success. The weather conditions during the feeding period of the nestlings varied within a season as well as between breeding seasons. The prevailing weather markedly affected both the growth rate and the survival of chicks, yet, the effects of weather on growth were not greater in enlar…
Limitation of Reproductive Success by Food Availability and Breeding Time in Pied Flycatchers
1998
Seasonal variation in reproductive success is a common phenomenon in many taxa. In birds, the costs and benefits associated with alternative breeding dates cause variation in clutch size, which is a main cause of seasonal decline in reproductive success. An immediate cause for this might be seasonal variation in the environment, or alternatively, but not mutually exclusively, date-independent differences in the parental/territory quality of early and late parents. The predictions of these hypotheses on seasonal reduction of reproductive success were tested by manipulating the hatching date and the amount of food during the nestling period of Pied Flycatchers (Ficedula hypoleuca). Delay in t…
Observed heterospecific clutch size can affect offspring investment decisions.
2011
Optimal investment in offspring is important in maximizing lifetime reproductive success. Yet, very little is known how animals gather and integrate information about environmental factors to fine tune investment. Observing the decisions and success of other individuals, particularly when those individuals initiate breeding earlier, may provide a way for animals to quickly arrive at better breeding investment decisions. Here we show, with a field experiment using artificial nests appearing similar to resident tit nests with completed clutches, that a migratory bird can use the observed high and low clutch size of a resident competing bird species to increase and decrease clutch size and egg…
REPRODUCTIVE SUCCESS OF EURASIAN TREECREEPERS,CERTHIA FAMILIARIS,LOWER IN TERRITORIES WITH WOOD ANTS
1999
Few studies have considered the effects of interspecific competition between distantly related taxa on the reproductive success of individuals. We compared the food supply, laying date, clutch size, and breeding success of a small double-brooded passerine bird, the Eurasian Treecreeper (Certhia familiaris) between territories with or without col- onies of red wood ants (Formica rufa group) during four years. Both the wood ants and Eurasian Treecreepers forage on tree trunks and utilize the same food resources. It has been shown that the wood ants are able to depress the available food supply for the treecreepers and interfere with their foraging behavior. We found that food abundance was lo…
Polygyny and Breeding Success of Pied Flycatchers Nesting in Natural Cavities
1990
Many hole-nesting passerine birds accept, or even prefer, nest boxes. Hence most of our knowledge about the breeding biology, population dynamics, life-history evolution and so forth of such species comes from nest box studies. This, in some cases, might lead to erroneous conclusions. For example, breeding density in nest box areas may often be much higher than in the natural situation (e.g. von Haartman, 1971), possibly leading to unnatural density dependent effects. Furthermore, the use of nest boxes may reduce predation risks (e.g. Nilsson 1975, 1984 a,b, Moller 1989), while the routine procedure of cleaning boxes after each breeding season may reduce the number of parasites, thus affect…
Effect of Incubation Body Mass on Reproductive Success and Survival of Two European Diving Ducks: A Test of the Nutrient Limitation Hypothesis
1997
The nutrient limitation hypothesis postulates that variation in nutrient reserves during egg laying and incubation are important predictors of future reproductive success of female waterfowl. We tested one component of this hypothesis in two European diving ducks, Common Pochard (Aythya ferina) and Tufted Duck (Aythya fuligula), relating body masses of incubating females to subsequent nest success, and to duckling and adult survival. We based our analyses on 3,224 Common Pochards and 1,812 Tufted Ducks captured and weighed during the last two weeks before ducklings hatched at Engure Marsh, Latvia, in 1978-1993. Adult (ASY) females from successful nests weighed significantly more than those …