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1.
J. Soltis R. Thomsen K. Matsubayashi O. Takenaka 《Behavioral ecology and sociobiology》2000,48(3):195-202
Infanticide was observed for the first time in a wild, non-provisioned troop of Japanese macaques on Yakushima Island, Japan.
Eight adult resident males attacked unweaned infants in the pre- and early mating season, and one infanticide was observed
directly. These attacks were not consistent with the social pathology, side effect of male aggression, cannibalism, or the
resource defense hypothesis, but were generally consistent with the sexual-selection hypothesis. First, most male attackers
had risen in dominance rank because several high-ranking males had left the troop. Second, in 78% of cases, male attackers
had not previously been observed to mate with the mothers of victims. Moreover, analysis of subject animal DNA showed that
males did not attack their own offspring. The two mothers who lost their unweaned infants, however, were not subsequently
observed to mate. In fact, almost no mating behavior was observed in the troop. This was most likely due to a poor fruiting
year. Resumption of mating by females who lost their infants may have been inhibited by an intervening environmental variable
which suppressed female reproductive function. These observations contribute to a growing body of evidence which suggests
that sexually selected infanticide can occur in seasonally breeding, multi-male, multi-female primate groups. Female Japanese
macaques are known to mate with multiple males. We found evidence that female mating with multiple males inhibits contact
aggression towards their infants. Adult males attacked infants eight times more often when they had not previously mated with
the mother.
Received: 2 September 1999 / Received in revised form: 27 April 2000 / Accepted: 3 May 2000 相似文献
2.
Relatedness, polyandry and extra-group paternity in the cooperatively-breeding white-browed scrubwren (Sericornis frontalis ) 总被引:3,自引:0,他引:3
Linda A. Whittingham Peter O. Dunn Robert D. Magrath 《Behavioral ecology and sociobiology》1997,40(4):261-270
We used DNA fingerprinting to examine the genetic parentage and mating system of the cooperatively breeding white-browed
scrubwren, Sericornis frontalis, in Canberra, Australia. Our analyses revealed a remarkable variety of mating tactics and social organization. Scrubwrens
bred in pairs or multi-male groups that consisted of a female and two or more males. Females were always unrelated to the
pair male or alpha (dominant) male. Among multi-male groups we found three different mating tactics. Firstly, when alpha and
beta (subordinate) males were unrelated, they usually shared paternity in the brood. This resulted in both males gaining reproductive
benefits directly. Secondly, when beta males were not related to the female but were related to the alpha males, beta males
sired offspring in some broods. In this situation, beta males gained reproductive benefits both directly and potentially indirectly
(through the related alpha male). Thirdly, when beta males were related to the female or both the female and alpha male, they
remained on their natal territory and did not sire any offspring. Thus beta males gained only indirect reproductive benefits.
Overall, when group members were related closely, the dominant male monopolized reproductive success, whereas when the members
were not related closely the two males shared paternity equally. This positive association between monopolization of reproduction
and relatedness is predicted by models of reproductive skew, but has not been reported previously within a single population
of birds. Other cooperatively breeding birds with both closely related and unrelated helpers may show a similar variety of
mating tactics. Finally, we found that extra-group paternity was more common in pairs (24% of young) than in multi-male groups
(6%), and we discuss three possible reasons for this difference.
Received: 21 May 1996 / Accepted after revision: 14 December 1996 相似文献
3.
Patrick J. Weatherhead 《Behavioral ecology and sociobiology》1997,40(3):151-158
Using data from a 6-year paternity study of red-winged blackbirds, I tested the hypotheses that increased nesting synchrony
should either promote extra-pair mating by increasing the advantage of extra-pair mating to females, or decrease extra-pair
mating by constraining males from seeking extra-pair copulations. Contrary to these hypotheses, the occurrence of extra-pair
paternity did not vary with nesting synchrony over the breeding season, or vary with the number of synchronous nests within
territories or within marshes, or with nesting order on territories. However, for nearly all nests with extra-pair young,
there were fewer females synchronous with that nest on the cuckolder's territory than on the territory of the cuckolded male.
This “advantage” of a synchrony difference was less pronounced for older males that cuckolded younger males, particularly
when the two males were not neighbors. Collectively, these results suggest that breeding synchrony affects extra-pair mating
by affecting mate guarding, but that breeding synchrony alone can not be used to predict which females are more likely to
engage in extra-pair mating, nor with which extra-pair males they will mate. Understanding why extra-pair mating by older
males is less affected by breeding synchrony may explain much about both the proximate and ultimate causes of extra-pair mating
in red-winged blackbirds.
Received: 7 June 1996 / Accepted after revision: 25 November 1996 相似文献
4.
Sexual cohabitation as mate-guarding in the leaf-curling spider Phonognatha graeffei Keyserling (Araneoidea, Araneae) 总被引:1,自引:1,他引:1
The leaf-curling spider Phonognatha graeffei incorporates a twisted leaf into the central hub of its orb-web that is used as a retreat. This species is unusual among orb-weaving
spiders because males cohabit in the leaf retreat with both immature and mature females, mating with the former shortly after
the female molts. Cohabitation appears to be a form of mate-guarding because cohabiting males respond agonistically to rival
males that venture onto the web, and their behaviour depends upon the reproductive status of the female; males defending immature
females are more aggressive than those defending virgin, adult females. Males copulate with previously mated females for significantly
longer than with virgin females. Females may cannibalise cohabiting males, which occurs independently of whether the female
has been deprived of food. Females that cannibalise a single male do not have a higher fecundity than non-cannibalistic females.
Received: 2 February 1996 / Accepted after revision: 27 October 1996 相似文献
5.
The evolution of non-maternal caretaking among anthropoid primates: do helpers help? 总被引:5,自引:0,他引:5
Non-maternal infant care among nonhuman primates has frequently been investigated from the perspective of the caretaker.
Here we examine whether allocaretaking behavior provides direct reproductive benefits to mothers. Comparative analyses that
control for the effects of allometry and phylogeny reveal that allocaretaking behavior correlates with relatively fast infant
growth and reproduction, but is not associated with the production of large infants. These results are consistent with those
from studies of other taxa; primate helpers appear to increase the reproductive success of female breeders. In addition, our
findings contrast with those derived from traditional allometric analyses and underscore the importance of controlling for
the potentially confounding effects of phylogeny in comparative analyses.
Received: 28 May 1996 / Accepted after revision: 16 November 1996 相似文献
6.
We estimated the cost to females of the lekking butterfly Coenonympha pamphilus of visiting males on leks instead of taking off and soliciting courtship from males passing them outside leks, as occurs
in the non-lekking congener C. tullia. We followed released virgin females of C. pamphilus in the field until they mated. We estimated the time they lost by remaining perched and not approaching males that passed
them, and observed how often and at what distance virgin females were passed by males in the field. We then calculated how
much faster these females would have been detected if they had taken off and approached these males, using probabilities of
detection as a function of passing distance derived from field observations on C. tullia females. C. pamphilus females on average lost 201 min by not approaching males on their way to leks. To estimate what this time loss meant in terms
of fitness, we measured how the age at mating affected fecundity. Using field measures of fecundity and mortality, the time
loss translated into an average 2.8% reduction in fecundity as a best estimate, and an average 1.3% reduction in fecundity
as a lower estimate. This fitness cost is larger than has been reported earlier for a lekking bird, but is probably too small
to eliminate the possibility of indirect benefits of mating with males on leks.
Received: 15 August 1996 / Accepted after revision: 24 January 1997 相似文献
7.
Correlates of extra-pair fertilization success in hooded warblers 总被引:13,自引:0,他引:13
Bridget J. M. Stutchbury W. H. Piper D. L. Neudorf S. A. Tarof Judith M. Rhymer G. Fuller R. C. Fleischer 《Behavioral ecology and sociobiology》1997,40(2):119-126
We examined correlates of extra-pair fertilization (EPF) success in the hooded warbler (Wilsonia citrina), a species where females pursue extra-pair matings. The good genes hypothesis predicts that females choose extra-pair mates
with morphological or behavioral traits that reflect differences in male genetic quality. EPFs were common, as 35.3% (42/119)
of broods contained extra-pair young (EPY) and 26.7% (95/356) of nestlings were the result of EPFs. There was a strong skew
in male EPF success which increased the variance in annual male mating success 2–3 fold. However, male morphology did not
predict EPF success, as extra-pair males were not older or larger than the males they cuckolded. Likewise, there were no significant
correlations between the proportion of extra-pair young in a brood and male size or age. The good genes hypothesis predicts
that high-quality males will be consistently preferred as genetic mates, but the number of young sired by a male with his
social mate was not consistent from one year to the next. There was a significant negative correlation between female age
and proportion of EPY produced, which could result if older females obtain higher-quality social mates. We found no strong
evidence that females choose extra-pair mates for good genes, but females may use behavioral rather than morphological cues
to assess relative male quality.
Received: 31 May 1996 / Accepted after revision: 17 October 1996 相似文献
8.
Ellen J. Censky 《Behavioral ecology and sociobiology》1997,40(4):221-225
Mate choice by females has been documented in a variety of taxa. Female mate choice in species lacking male resource control
or paternal care might occur if preferred males provide protection from harassment. Female mate choice was investigated in
a natural population of the non-territorial lizard Ameiva plei (Teiidae). Consort pairs were allowed to form naturally. Consort males were significantly larger than non-consort males.
After removal of consort males, the “abandoned” female's reaction to the first male who approached her was recorded. Females
rejected all small males. Female preference for large males was significantly higher than preference for small males. Large
males may be better equipped to guard the females from harassment and behavior of large males is less harassing than behavior
of small males, thereby affording the female increased foraging time.
Received: 21 June 1996 / Accepted after revision: 28 December 1996 相似文献
9.
A molecular genetic analysis of social structure, dispersal, and interpack relationships of the African wild dog (Lycaon pictus ) 总被引:7,自引:0,他引:7
Derek J. Girman M. G. L. Mills Eli Geffen Robert K. Wayne 《Behavioral ecology and sociobiology》1997,40(3):187-198
The African wild dog is a highly social, pack-living predator of the African woodland and savannah. The archetypal wild dog
pack consists of a single dominant breeding pair, their offspring, and non-breeding adults who are either offspring or siblings
of one of the breeding pair. Non-breeding adults cooperate in hunting, provisioning and the protection of young. From these
observations follows the prediction that the genetic structure of wild dogs packs should resemble that of a multigenerational
family, with all same-sexed adults and offspring within a pack related as sibs or half-sibs. Additionally, a higher kinship
between females from neighboring packs should be evident if females tend to have small dispersal distances relative to males.
We test these predictions through analysis of mitochondrial DNA control region sequences and 14 microsatellite loci in nine
wild dog packs from Kruger National Park, Republic of South Africa. We show that as predicted, African wild dog packs generally
consist of an unrelated alpha male and female, subdominant close relatives, and offspring of the breeding pair. Sub-dominant
wild dogs occasionally reproduce but their offspring rarely survive to 1 year of age. Relatedness influences the timing and
location of dispersal events as dispersal events frequently coincide with a change in pack dominance hierarchy and dispersers
often move to areas with a high proportion of close relatives.
Received: 22 February 1996 / Accepted after revision: 16 November 1996 相似文献
10.
José L. Tella Manuela G. Forero José A. Donázar Juan J. Negro Fernando Hiraldo 《Behavioral ecology and sociobiology》1997,40(4):253-260
We examined the causes, costs and benefits of adoption in the altricial lesser kestrel Falco naumanni. Specifically, we tested the intergenerational conflict hypothesis, proposed to explain adoption in some birds. Adoptions
involved 76% of the nests and 51% of the nestlings at a mean age of 25 days (12 days before fledging). Nest-switching nestlings
were not in poorer body condition, more parasitized or younger than their siblings, and body condition and prey delivery rates
of their parents did not differ from those of other parents. In the foster nest, adopted nestlings did not benefit from higher
feeding rates or a prolongation of the nestling period. They did not have fewer nest-mates or achieve higher rank within the
new brood. Thus, adopted nestlings did not improve their body condition and survival. Adult lesser kestrels seemed unable
to finely discriminate beween their own and alien chicks. Foster parents bore the cost of an increase of prey delivery rates,
although it did not affect their survival or subsequent reproductive performance. Therefore, our results do not support the
intergenerational conflict hypothesis, and suggest that adoption in this species is non-adaptive. Traditionally, the lesser
kestrel bred in cliffs where movement among nest-sites was restricted. Nowadays, about half of the colonies are in tiled roofs
which facilitate nest-switching by nestlings. The high rate of adoptions may thus be explained as reproductive errors associated
with the recent occupation of a new breeding habitat.
Received: 3 May 1996 / Accepted after revision: 19 January 1997 相似文献
11.
Ornamentation predicts reproductive success in female pipefish 总被引:5,自引:0,他引:5
Anders Berglund Gunilla Rosenqvist Patricia Bernet 《Behavioral ecology and sociobiology》1997,40(3):145-150
In the sex-role reversed pipefish Syngnathus typhle females compete for access to males and males are choosy. Females develop a temporary ornament when competing over mates
with other females and when performing nuptial dances with males. This ornament is an amplification of the normal striped
pattern in these fishes. We here show experimentally that (1) the contrast of this normal pattern forecasts the extent to
which the ornament is shown, (2) contrast and ornamentation honestly signal female quality (egg numbers), (3) contrast and
ornamentation accurately predict female mating success, (4) contrast is a phenotypically plastic trait specifically exaggerated
under situations of female – female competition, and (5) neither contrast nor ornament are energetically expensive to the
females (i.e., they are independent of short-term nutritional status). Hence, as predicted in sex-role reversed species, ornament
design is constrained by costs to female fecundity: an energetically demanding ornament would impair on a female's ability
to produce eggs. The type of ornament described here is the expected one, costly for reasons other than being energetically
expensive to produce.
Received: 4 April 1996 / Accepted after revision: 27 October 1996 相似文献
12.
Reproductive dominance and differential ovicide in the communally breeding burying beetle Nicrophorus tomentosus 总被引:4,自引:0,他引:4
Michelle Pellissier Scott 《Behavioral ecology and sociobiology》1997,40(5):313-320
Communal breeding can be characterized by the division of reproduction among cooperating individuals and, if the distribution
of reproduction is inequitable, by the mechanisms for achieving skewed reproductive success. The burying beetle (Nicrophorus tomentosus) is a facultative communal breeder. Unrelated adults, especially females, provide extensive parental care to broods of mixed
parentage. The frequency and degree of reproductive skew between two females were examined experimentally. On medium-size
carcasses, the proportion of eggs attributed to each female was not significantly different from random in 42% of the broods,
skewed in 42% and not shared in 16%. Although reproduction was usually skewed in favor of the larger female, the relative
sizes of the two females did not predict the degree of skew. On large carcasses, the proportion of eggs attributed to each
female was not different from random in 87% of the broods and weakly skewed in 13%. Several mechanisms for biasing reproductive
success were investigated. Females increase the proportion of their offspring in the brood by committing differential ovicide.
Secondly, burying and preparing a carcass cooperatively stimulates ovarian development of the larger female and slows it for
the smaller female, reducing or delaying oviposition by the subordinate. Thirdly, larger females are more likely to be dominant
and are more fecund than smaller females.
Received: 20 July 1996 / Accepted after revision: 30 November 1996 相似文献
13.
Carola Borries Kristin Launhardt Cornelia Epplen Jörg T. Epplen Paul Winkler 《Behavioral ecology and sociobiology》1999,46(5):350-356
Hypotheses about the evolution of gregariousness and social organisation in primates are based on ecological explanations
as well as on social factors such as conspecific threat (especially infanticide by males). The social explanation fits well
with the conditions found in strepsirrhine primates and furthermore explains why infanticide in anthropoid primates living
in one-male groups mainly occurs when the resident male (protector) is replaced. However, whether it likewise fits to the
conditions in multimale groups will depend on the role of resident males as infant protectors, which has rarely been examined.
We investigated long-term data of wild Hanuman langurs (Presbytis entellus) inhabiting a forest near the village of Ramnagar (southern Nepal). Twenty-two eye-witnessed attacks on infants by males
were analysed in connection with male residency, paternity (DNA analyses) and sexual behaviour. Adult males played a major
role in infant defence (65%). Only the genetic father or males who had been residents when the infant was conceived were observed
to protect infants. Males who immigrated after a female had conceived may later attack her infant and were never observed
to defend it. lt seems that the males took only copulations with potentially fertile females but not with pregnant females
as clues for paternity. In the light of these results it seems likely that the risk of infanticide is an important determinant
in female-male associations even in anthropoid primate multimale groups.
Received: 22 December 1998 / Received in revised form: 30 April 1999 / Accepted: 1 May 1999 相似文献
14.
P. Jivoff 《Behavioral ecology and sociobiology》1997,40(3):175-185
In many species, post-copulatory mate guarding prevents other males from mating with the guarded female. In crabs, males
stay with their mates to protect the female from predators because, in some species, mating occurs when she is soft and vulnerable
after molting. I tested the relative roles of sperm competition and predation on the duration of the post-copulatory association
in the blue crab, Callinectes sapidus. Unpaired females suffered greater predation mortality than paired females and males stayed with the female longer in the
presence of predators than in their absence, suggesting that the post-copulatory association protects females during their
vulnerable period. However, the association may also occur in blue crabs because of sperm competition since spermathecal contents
of females in the field indicate that 12.4% mated twice. Females experimentally mated with two males contained both males
ejaculates and each ejaculate had access to the unfertilized eggs, suggesting that the size of a male's ejaculate influences
his fertilization rate in a multiply-mated female. Males stayed longest in response to a high risk of sperm competition. Longer
post-copulatory associations allowed the first male's ejaculate to harden into a type of sperm plug, which limited the size
of a second inseminator's ejaculate in a non-virgin female as compared with a virgin. Males passed larger ejaculates in the
presence of rivals and when previous ejaculates were in the female spermathecae, another response to sperm competition. Larger
ejaculates may need longer post-copulatory associations before a more effective sperm plug forms. Large males stayed with
the female longer, which is consistent with their ability to pass larger ejaculates than small males and suggests that there
may be costs to minimizing the duration of the post-copulatory association. In the field, associations last long enough to
protect the female during her vulnerable phase and may ensure that the guarding male fertilizes the most eggs in the female,
even if she remates. Thus, the post-copulatory association protects female blue crabs from additional inseminators as well
as from predators.
Received: 23 January 1996 / Accepted after revision: 9 November 1996 相似文献
15.
Past reproductive success affects future habitat selection 总被引:4,自引:0,他引:4
Paul V. Switzer 《Behavioral ecology and sociobiology》1997,40(5):307-312
Correlational studies have shown that an individual's past reproductive success often increases its breeding site fidelity
(i.e., the tendency to return to a previously occupied location), suggesting that individuals use their reproductive experience
to assess habitat quality. However, the causality of the relationship between reproductive success and site fidelity is still
uncertain. In a field experiment, the effect of mating success on site fidelity was isolated from potential confounding variables
in a territorial dragonfly, the eastern amberwing (Perithemis tenera). The experiment controlled for site quality, intrinsic characteristics of males, previous territorial experience at the
site, arrival order, and territorial evictions. Males that were prevented from mating were much more likely to change sites
the following day than control males that were allowed to mate. This result was not affected by age, the amount of time a
male spent on the site, or mortality. These results imply that individuals use their own reproductive success to assess the
quality of the habitat. The benefit to an individual of using its reproductive success to determine habitat quality is discussed
relative to other sources of information.
Received: 31 May 1996 / Accepted: 31 January 1997 相似文献
16.
Common goldeneyes adjust maternal effort in relation to prior brood success and not current brood size 总被引:3,自引:0,他引:3
Parental investment theory predicts that parental effort should be related to the reproductive value of the current brood.
This depends on both the number of young and the survival prospects of each of them. Thus parents may provide more care to
larger broods either because of (1) the direct effect of brood size per se on reproductive value (the “brood size” hypothesis)
or because (2) past mortality, reflected in current brood size, predicts future mortality of the brood and hence its reproductive
value (the “brood success” hypothesis). Earlier studies have not attempted to distinguish between these alternatives. We tested
the hypotheses in the precocial, nidifugous common goldeneye Bucephala clangula, a species with uniparental female care. Maternal effort was measured as the time spent by the female in rearing the brood.
We found that brood size itself is not associated with maternal effort, but that females modify their maternal effort according
to the mortality already experienced by the brood, supporting the prediction of the brood success hypothesis. We also found
that brood mortality varied considerably between broods and that previous mortality predicts future mortality within broods,
basic assumptions of the brood success hypothesis.
Received: 30 January 1996 / Accepted after revision: 27 October 1996 相似文献
17.
Quality-indicating sexually selected traits may have their honesty maintained by their costs or by an inherent “revealing”
nature. Long tails in birds are usually considered to be costly “handicaps”, but may have additional potential as revealing
indicators through the incidence of breakage. Magpies Pica pica with unbroken and less abraded tails paired earlier, but did not nest or fledge young earlier than pairs with tails in poorer
condition. Pairs mated assortatively by tail quality, and magpies with very broken tails remained unmated. Pairs in which
both members had almost undamaged tails fledged more offspring than pairs with poorer tails. Tail quality did not correlate
with the extent of any habitat type in the territory. Tail damage thus honestly indicated a magpie's reproductive potential,
and the data are consistent with its having a role in mate choice, as a revealing element of tail morphology.
Received: 28 March 1996 / Accepted after revision: 9 December 1996 相似文献
18.
Lack of kin recognition in swarming honeybees ( Apis mellifera ) 总被引:2,自引:0,他引:2
Honeybee colonies reproduce by colony fission and swarming. The primary swarm leaves the nest with the mated mother queen.
Further “after-swarms” can leave the nest. These are composed of virgin queens and sister workers. Since all workers in the
primary swarm have the same relationship to the mother queen, kin recognition cannot have any effect on the worker distribution
in the swarm. Because of polyandry of the mother queen, the after-swarm is composed of super- and halfsister workers of the
virgin queen. In this case kin recognition might affect swarm composition if workers increase their inclusive fitness by preferentially
investing in a supersister queen. The distribution of workers in the mother colony, the primary and the after-swarm was analyzed
using single-locus DNA fingerprinting in two colonies of the honeybee (Apis mellifera). The colonies were composed of 21 and 24 worker subfamilies because of multiple mating of the queen. The subfamily distribution
in the mother colonies before swarming was significantly different from the subfamily frequencies in the primary swarm. This
indicates different propensities for swarming in the various subfamilies. The subfamily distribution was also significantly
different between the mother colony and the after-swarm. There was however no significant difference between the subfamily
composition of the primary and the after-swarm. The average effects of kin recognition on the distribution of the subfamilies
in the two after-swarms were less than 2%. We conclude that colony-level selection sets the evolutionary framework for swarming
behaviour.
Received: 22 May 1996 / Accepted after revision: 2 November 1996 相似文献
19.
Russell C. Titus C. Ray Chandler Ellen D. Ketterson Val Nolan Jr. 《Behavioral ecology and sociobiology》1997,41(3):165-169
Frequency of singing by birds may vary with reproductive stage in ways that reflect variation in the functions of song in
intersexual and intrasexual communication. In dark-eyed juncos (Junco hyemalis) high-amplitude song is produced only by males. To investigate the function of this song, we tested whether fertility of
females affected singing by their mates or by neighboring males. Using focal observations, song censuses, and radiotracking
data, we determined whether song production varied between and among periods when females were fertile and non-fertile. Our
findings show that males do not increase song production when their mates are fertile, nor do they increase song production
when neighboring females are fertile. These results suggest that male juncos do not signal their intent to defend territories
(or mates) more when females are fertile and that they do not use song to advertise to specific potential participants in
extra-pair fertilizations.
Received: 13 February 1997 / Accepted after revison: 2 May 1997 相似文献
20.
D. A. Westcott 《Behavioral ecology and sociobiology》1997,40(4):235-242
Interactions between males on leks may play an influential role in lek formation and the regulation of lek size. In this
paper I present the results of a playback experiment that simulated de novo settlement at sites adjacent to currently existing display territories of the ochre-bellied flycatcher, Mionectes oleagineus. In the study population, males displayed both solitarily and at small leks. A large proportion of males held no display
territory at all. A stranger's song was played to both solitary and lekking males from 10 m outside their territorial boundaries.
In separate playbacks, lekking males were also played neighbour's song. Both lekking and solitary territorial males reacted
to the playback by decreasing their song rate, approaching the playback speaker and, on occasion, attacking the model. Solitarily
displaying males responded more aggressively to playback of stranger's song than did lek males. Lek males were able to distinguish
between their neighbour's and a stranger's song and did so irrespective of whether it was played from the neighbour's territory
or from outside the lek. In addition to distinguishing between neighbours and strangers, lek males modified their responses
to these different playbacks depending on where the playback originated. These results suggest that male-male interactions
can be influential in structuring leks. In M. oleagineus, interactions between males are aggressive and act to limit rather than augment lek size.
Received: 6 March 1996 / Accepted after revision: 9 December 1996 相似文献