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121.
Female control of offspring paternity in a western population of red-winged blackbirds (Agelaius phoeniceus) 总被引:9,自引:0,他引:9
E. M. Gray 《Behavioral ecology and sociobiology》1996,38(4):267-278
Extra-pair copulations, which occur when individuals that have formed social relationships to breed copulate outside their
pairbond, now are recognized as an important component of reproductive success in many species. In situations where both males
and females benefit from extra-pair copulations without incurring much risk, an inevitable conflict arises between pairbonded
mates. In this study I investigated the conflict of interest between male and female reproductive strategies in a western
population of red-winged blackbirds (Agelaius phoeniceus). Female red wings in this population initiate extra-pair copulations, which resulted in a 35% rate of extra-pair fertilization.
Females initiated the majority (78%) of extra-pair copulations away from their nesting territory where pairbonded individuals
typically copulate, and females that engaged in extra-pair copulations spent a significantly greater amount of time off the
marsh during peak fertilization compared to females that did not. In addition, females that nested in areas with a large number
of potential extra-pair partners produced significantly more extra-pair fertilized young compared to females that nested on
marshes with few male neighbors. Males’ strategies to protect paternity were limited primarily to patrolling territory boundaries
and to opportunistically preventing extra-pair copulations off the marsh when they were visible. In this population females
appear to use behavioral means to control nestling paternity, which in turn directly affected their mate’s reproductive success,
and males were restricted to using strategies that were largely ineffective at preventing the threat of extra-pair paternity.
Received: 23 December 1994/Accepted after revision: 17 December 1995 相似文献
122.
Raphaël Boulay Abraham Hefetz Xim Cerdá Séverine Devers Wittko Francke Robert Twele Alain Lenoir 《Behavioral ecology and sociobiology》2007,61(10):1531-1541
Models based on the kin selection theory predict that in social hymenopterans, queens may favor a lower investment in the
production of sexuals than workers. However, in perennial colonies, this conflict may be tuned down by colony-level selection
because of the trade off between colony survival and reproductive allocation. In this study, we present a survey of sexual
production in colonies of Aphaenogaster senilis, a common species of ant in the Iberian Peninsula. Similar to most species that reproduce by fission, males were found in
large excess compared to gynes (172:1). Sexuals were more likely to be found in queenless than in queenright (QR) field colonies.
However, we also found a few gynes and numerous males in very large QR colonies. We compared these data with those available
in the literature for A. rudis, a congeneric species from North America that has independent colony founding. The sex ratio in this species was only five
males for each female, and sexuals were mostly found in QR nests, irrespective of colony size. We confirmed queen inhibition
of sexual production in A. senilis in laboratory experiments and provide evidence that this inhibition is mediated by a nonvolatile pheromone. To seek the potential
source of such a queen pheromone, we analyzed the secretions of two conspicuous exocrine glands, the Dufour’s and postpharyngeal
glands (DG and PPG, respectively) in both queens and workers. Both secretions were composed of hydrocarbons, but that of DG
also contained small quantities of tetradecanal and hexadecanal. The hydrocarbon profile of the DG and PPG showed notable
caste specificity suggesting a role in caste-related behavior. The PPG secretions also differed between colonies suggesting
its role in colony-level recognition. We suggest that in A. senilis, there are two modes of colony fission: First, in very large colonies, gynes are produced, probably because of the dilution
of the queen pheromone, and consequently one or more gynes leave the mother colony with workers and brood to found a new nest.
This is beneficial at the colony level because it avoids the production of costly sexuals in small colonies. However, because
the queen and workers have different optima for sexual production, we hypothesize that queens tend to overproduce the pheromone
to delay their production. This in turn may drive workers to leave the mother colony during nest relocation and to produce
sexuals once they are away from the queen’s influence, creating a second mode of colony fission. 相似文献
123.
Troy G. Murphy 《Behavioral ecology and sociobiology》2007,61(6):911-918
Both males and females of many avian species maintain elaborate plumage traits, and elaborate monomorphic plumage may convey
adaptive benefits to one or both sexes as inter- or intraspecific signals. Both sexes of the turquoise-browed motmot (Eumomota superciliosa) are elaborately plumed with long racket-tipped tail. I investigated whether the racketed tail functions as a sexually selected
signal in one or both sexes by testing the predictions that males and/or females with the largest tails have: (1) greater
pairing success, (2) greater reproductive performance (clutch-initiation date, clutch size, and hatching success), and (3)
greater reproductive success. Yearling males with longer denuded rachises (wires) on the central tail feathers had greater
pairing success. In addition, adult males with longer wires paired with females who laid larger clutches, had greater hatching
success independent of clutch size, and fledged more young. There was no relationship between female tail plumage and pairing
success, reproductive performance, or fledgling success. These results are consistent with the hypothesis that male tail plumage
functions as a mate choice or status signal, but that the tail of the female does not function in a sexually selected context.
I discuss alternative hypotheses for the evolutionary maintenance of the elaborate female tail plumage. 相似文献
124.
The reproductive trade-off hypothesis predicts that the investment made in current reproduction determines the breeders’ future fitness as a consequence of intra-or inter-generational reproductive costs. Long-lived species are expected to favour their own reproductive value at the expense of their offspring, hence incurring in inter-generational costs, whereas short-lived species are expected to invest in the current breeding attempt even at the expense of their own survival, thus incurring in intra-generational costs. We tested whether intensity of current reproductive effort has intra-or inter-generational costs in a short-lived bird, the blue tit Parus caeruleus, with a brood size manipulation experiment. We expected more intra-generational (parental reproduction and/or survival) than inter-generational (offspring quality and survival) reproductive costs. We found that parental effort, measured as the hourly rate of parental visits to nests, increased gradually with experimental manipulation. Brood size manipulation resulted in a gradual increase in the number of fledglings per nest from reduced to increased treatments. We found an effect of the manipulation on the probability of making a second clutch, with adults rearing enlarged broods being less likely to undertake such a second reproduction during the season compared to those rearing control or decreased broods. We found no evidence of other reproductive costs; neither as adult weight after manipulation, apparent parental local survival, apparent offspring local survival or local recruitment. Although the results seem to support the a priori expectations, alternative explanations are discussed.Communicated by M. Soler 相似文献
125.
Satoshi Awata Hiroyuki Munehara Masanori Kohda 《Behavioral ecology and sociobiology》2005,58(5):506-516
It is suggested that some fish of the genus Julidochromis, substrate-brooding Tanganyikan cichlids with biparental care, breed cooperatively with helpers. We studied the social system of J. ornatus in the wild and analysed genetic parentage using microsatellites. Within the studied population three patterns of social system were identified: monogamous pairs (61%, 44 of 72 groups), pairs with helpers (29%, 21), and polygamous harems with helpers (controlled by either a large female or large male owner; 10%, 7). In cooperatively breeding groups, the number of helpers at each nest ranged from 1 to 6 (median 1), and male helpers were more numerous than female helpers. In both sexes, the body size was different among individuals of different social status (harem owner > breeder > helper). Helpers and harem owners of both sexes exhibited brood defence although its frequency was low. The molecular analysis revealed that (1) the helpers were mostly unrelated to dominant breeders, (2) many helpers of both sexes contributed genetically to the next generations, (3) male helpers had high siring success (41% of young in total), and (4) large young unrelated to group members were detected at 30% of observed nests, which may be due to breeder (or helper) replacements and immigration of young. We discuss the implications of these results for understanding the complex social system of this species, especially the low reproductive skew in comparison with other cooperatively breeding cichlids. 相似文献
126.
Natsuko Ito Kondo Daisei Yamanaka Yuya Kanbe Yoko Kawate Kunitake Masahiro Yoneda Koji Tsuchida Koichi Goka 《Die Naturwissenschaften》2009,96(4):467-475
The European bumblebee, Bombus terrestris, is an invasive eusocial species whose distribution is expanding greatly beyond its native range because numerous colonies
are imported to or locally produced in non-native countries for pollination of agricultural crops. Closely related species
exist in Japan where the unrestricted import and use of B. terrestris has resulted in the establishment of wild colonies. Laboratory studies previously showed that B. terrestris and Japanese native species can copulate and produce fertilized eggs. Although these eggs do not hatch, the interspecific
mating can cause a serious reproductive disturbance to native bumblebees. In this study, we determined the frequencies of
interspecies mating between B. terrestris males and native bumblebee queens in the wild on the islands of Hokkaido and Honshu by analyzing the DNA sequences of spermatozoa
stored in spermathecae of native queens. We found that 20.2% of B. hypocrita hypocrita queens and 30.2% of B. hypocrita sapporoensis queens had spermatozoa of B. terrestris males in their spermathecae. Given that a Bombus queen generally mates only once in her life, such high frequencies of interspecific mating with B. terrestris pose serious threats to the populations of native bumblebees in Japan. 相似文献
127.
Michael J. L. Magrath Peter Santema Karen M. Bouwman Dušan M. Brinkhuizen Simon C. Griffith Naomi E. Langmore 《Behavioral ecology and sociobiology》2009,63(5):661-672
Reproductive success within populations often varies with the timing of breeding, typically declining over the season. This
variation is usually attributed to seasonal changes in resource availability and/or differences in the quality or experience
of breeders. In colonial species, the timing of breeding may be of particular importance because the costs and benefits of
colonial breeding are likely to vary over the season and also with colony size. In this study, we examine the relationship
between timing of breeding and reproductive performance (clutch size and nest success) both within and between variable sized
colonies (n = 18) of fairy martins, Petrochelidon ariel. In four of these colonies, we also experimentally delayed laying in selected nests to disentangle the effects of laying
date and individual quality/experience on reproductive success. Within colonies, later laying birds produced smaller clutches,
but only in larger colonies. The general seasonal decline in nest success was also more pronounced in larger colonies. Late
laying birds were generally smaller than earlier laying birds, but morphological differences were also related to colony size,
suggesting optimal colony size also varies with phenotype. Experimentally delayed clutches were larger than concurrently produced
non-delayed clutches, but only in larger colonies. Similarly, delayed clutches were more likely to produce fledglings, particularly
later in the season and in larger colonies. We suggest that the reduced performance of late breeding pairs in larger colonies
resulted primarily from inexperienced/low quality birds preferring to settle in larger colonies, possibly exacerbated by an
increase in the costs of coloniality (e.g., resource depletion and ectoparasite infestations) with date and colony size. These
findings highlight the importance of phenotype-related differences in settlement decisions and reproductive performance to
an improved understanding of colonial breeding and variation in colony size. 相似文献
128.
The primates of Madagascar (Lemuriformes) are unusual among mammals in that polygynous species lack sexual dimorphism, and
females dominate males socially in most species. Moreover, lemur groups are relatively small and characterized by even adult
sex ratios despite the fact that one male should be able to exclude other males from the group. One hypothesis to explain
this combination of behavioral, morphological, and demographic traits (the “lemur syndrome”) postulates that male–male competition
is relaxed and, hence, variance in male reproductive success is low. Reproductive skew theory provides a framework for testing
this and several related predictions about lemur social evolution. Specifically, low reproductive skew is also predicted if
dominant males or adult females make reproductive concessions to subordinates or if the latter group successfully pursues
alternative reproductive tactics. However, suitable data on paternity, demography, and behavior for a conclusive test of these
predictions have not been available in the past. In this paper, we show that male reproductive success in ten groups of Verreaux’s
sifakas (Propithecus verreauxi) was extremely skewed in favor of the dominant male over 9 years. Our genetic analyses also revealed that more than a third
of all groups are effectively harem groups because only one male was unrelated to the resident female(s). In groups with two
or more non-natal males, the dominant sired 91% of 33 infants. Together, males pursuing one of several alternative reproductive
tactics, such as roaming among several groups or immigrating peacefully, sired only 11% of infants. Thus, female sifakas do
not control group composition by offering reproductive opportunities to subordinate males as staying incentives, intrasexual
selection is not relaxed, and dominant males prevail in a tug-of-war over subordinate males. Because male reproductive skew
in sifakas is even more pronounced than in harem-living anthropoids studied to date, intrasexual selection is clearly not
relaxed, and the lemur syndrome is more puzzling than ever. 相似文献
129.
Masashi Kiyota Stephen J. Insley Stacey L. Lance 《Behavioral ecology and sociobiology》2008,62(5):739-746
We conducted a 6-year longitudinal behavioral and genetic investigation of a highly polygynous pinniped, the northern fur
seal (Callorhinus ursinus), to determine the contribution of terrestrial polygyny to male fertilization success and to assess the occurrence of alternative
mating strategies. Genetic samples from 37 adult males, 50 adult females, and 85 pups were collected and genotyped using five
polymorphic microsatellite loci. Pup paternity was assigned using Cervus 2.0 at 99% confidence level. Paternity of 83 pups
(98%) was assigned to terrestrial males who held territories or stayed temporarily in the study area during the breeding season
when fertilization occurred. For 56 pups of which attendance records of their mothers were available, paternity of 45 pups
(80%) was assigned to the associate males in whose territory their mothers stayed during the perioestrus period. In addition
to defending breeding territories, territorial males have often been observed attempting to forcibly abduct adult females
from adjacent territories (female stealing): We observed a total of 95 such cases, in which the stealers had significantly
fewer females than the territorial males from whose territories they stole females. Our results indicate that terrestrial
resource-defense polygyny is the major mating system in this species and that nonassociated paternity occurs mostly as a result
of alternative mating strategies of less successful males. Male northern fur seals thus appear to adopt conditional alternative
strategies that depend on their current social status to maximize their life-time reproductive success. 相似文献
130.
Dominance status influences the fitness of many mammals. Using African striped mice Rhabdomys pumilio, we tested whether (1) dominant females have greater reproductive success than subordinate females, (2) dominant females
influence the reproductive output of subordinate females when they are housed in close proximity, (3) reproductive output
of a female changes in response to the dominance status of her neighbours, and (4) whether prolonged association between individuals
influences the variance in reproductive success between dominants and subordinates (i.e. the ‘dear enemy’ phenomenon). The
size and mass of litters of dominants increased significantly when housed adjacent to subordinates than when housed apart.
The litter size and mass of subordinates remained unchanged, although subordinates spent significantly more time with their
pups when housed close to dominants than when housed apart; time spent with pups by dominants remained unchanged. Moreover,
females modified their reproductive output and behaviour in relation to the dominance status of their neighbours. Following
prolonged association, dominants still had greater reproductive success, but now, the time spent with pups decreased in subordinates.
We suggest that dominants adopt a strategy to increase the reproductive value of their litter, whereas subordinates adopt
a pup defence strategy. These strategies are flexible and are influenced by the dominance status and period of association
between neighbours, so that females could maximize their fitness in response to varying social conditions. 相似文献