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1.
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
2.
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
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.
Janine R. Clemmons 《Behavioral ecology and sociobiology》1997,40(4):243-251
In a variety of avian species, vocalizations used to stimulate gaping in nestlings during feeding share similar features
such as broad frequency range, multiple spectral components, and sudden onset. It is currently not understood what functional
significance, if any, these acoustic features have for close-range communication. One example of such a vocalization is the
“squawk” of the black-capped chickadees (Parus atricapillus). The present study analyzes the significant features of the squawk by observing the response of chickadee nestlings to field
playbacks of natural and computer-modified squawks. Of the features tested, frequency range appears most critical, but responses
to frequency ranges change with age, such that low frequencies are most stimulating around the time of hatching but cease
to elicit gaping after 5 days posthatch. Aperiodic stimuli and computer-modified squawks with gradual onsets tend to be less
stimulating than natural squawks at some ages, but these differences are not significant at any age. The functional significance
of the broad frequency range of the squawk is discussed, including the possible role of accommodating shifting frequency preferences
related to ontogenetic changes in auditory sensitivity and elaboration of the vocal repertoire.
Received: 16 January 1996 / Accepted after revision: 28 December 1996 相似文献
5.
Bertrand Schatz Jean-Paul Lachaud Guy Beugnon 《Behavioral ecology and sociobiology》1997,40(6):337-349
According to the weight and size of their prey, Ectatomma ruidum workers can employ different recruitment systems (solitary hunting, cooperative hunting and group hunting with recruitment)
when mastering and retrieving prey items from short distances from the nest. Prey size determined the backwards entry typically
adopted by this species, while prey weight determined the predatory strategy selected. After a common initial sequence (search
for prey, detection, localization), predatory sequences varied in terms of the type of approach, the site of seizure, the
reaction after stinging and the type of transport. Nevertheless, irrespective of prey weight and size, seizure was preferentially
oriented towards the head and prey were always stung. Short-range recruitment and mass recruitment without trail laying were
elicited by a large range of heavy prey (> 2.5 times the weight of an individual worker). According to the mortality risk
associated with each prey, hunters exhibited a “prudent” stinging posture associated with an increase in the duration of the
subsequent phase of waiting for prey immobilization. The overall time of capture was positively correlated with the weight
of the prey. When collective hunting strategies were involved, E. ruidum colonies matched the number of recruited hunters to the size and weight of the prey. Compared to solitary hunting strategies,
for short food–nest distances, this graded recruitment appeared to enhance the energetic benefits derived by this species
from the use of recruitment systems: the higher the number of workers involved in the recruitment process, the greater the
energetic benefits obtained. The exhibition or absence of trail laying behavior in the recruitment responses displayed by
E. ruidum workers is discussed in relation to their involvement in scavenging or predatory behavior.
Received: 27 June 1996 / Accepted after revision: 3 March 1997 相似文献
6.
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
7.
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
8.
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
9.
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
10.
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
11.
Female mallard mating preferences for multiple male ornaments 总被引:3,自引:1,他引:3
K. E. Omland 《Behavioral ecology and sociobiology》1996,39(6):353-360
Mating preferences were studied in captive wild-stock female mallards. Independent observers scored ornament brightness for
the bill and eight plumage areas of male mallards on a scale of 1 to 6. Ornament scores were generally positively correlated
with each other as indicated by univariate correlations and principal component analysis. Males with higher bill scores were
significantly more likely to obtain pairings. None of eight individual plumage ornaments were significant predictors of pairing
success, but males with higher average plumage scores had significantly higher pairing success. Males that completed the molt
first were also significantly more likely to be paired. Thus females may have paid some attention to plumage brightness. Stepwise
multiple regression produced a model that included only bill and molt, both of which contributed a similar degree (r
2 = 0.39); plumage ornaments and size measurements did not enter the model. These results are interpreted in light of hypotheses
for the evolution of multiple ornaments, and phylogenetic plumage patterns in dabbling ducks.
Received: 18 December 1995 / Accepted after revision: 22 September 1996 相似文献
12.
Multiple-queen (polygyne) colonies of the introduced fire ant Solenopsis invicta present a paradox for kin selection theory. Egg-laying queens within these societies are, on average, unrelated to one another,
and the numbers of queens per colony are high, so that workers appear to raise new sexuals that are no more closely related
to them than are random individuals in the population. This paradox could be resolved if workers discriminate between related
and unrelated nestmate sexuals in important fitness-related contexts. This study examines the possibility of such nepotism
using methods that combine the following features: (1) multiple relevant behavioral assays, (2) colonies with an unmanipulated
family structure, (3) multiple genetic markers with no known phenotypic effects, and (4) a statistical technique for distinguishing
between nepotism and potentially confounding phenomena. We estimated relatedness between interactants in polygyne S. invicta colonies in two situations, workers tending egg-laying queens and workers feeding maturing winged queens. In neither case
did we detect a significant positive value of relatedness that would implicate nepotism. We argue that the non-nepotistic
strategies displayed by these ants reflect historical selection pressures experienced by native populations, in which nestmate
queens are highly related to one another. The markedly different genetic structure in native populations may favor the operation
of stronger higher-level selection that effectively opposes weaker individual-level selection for nepotistic interactions
within nests.
Received: 28 June 1996 / Accepted after revision: 6 October 1996 相似文献
13.
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
14.
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
15.
Seasonally breeding predators, which are limited in the time available for provisioning young at a central location, and
by the fasting abilities of the young, are likely to maximize energy delivery to the young by maximizing the rate of energy
delivery averaged over the whole period of investment. Reduction in food availability or increased foraging costs will alter
the optimal behavior of individuals. This study examined the behavioral adaptations of a diving predator, the Antarctic fur
seal, to increased foraging costs during lactation. One group of mothers (n=5, treatment) was fitted with additional drag to increase the cost of transport in comparison with a control group (n=8). At the scales of the individual dives, the treatment group made more shorter, shallower (< 30 m) dives. Compensation for
slower swimming speeds was achieved by diving at a steeper angle. Overall, diving behavior conformed to several specific theoretical
predictions but there were also departures from theory, particularly concerning swimming speed during diving. Diving behavior
appears to be adjusted to maximize the proportion of time spent at the bottom of dives. At the scale of diving bouts, no difference
was observed between the treatment and control groups in terms of the frequency and duration of bouts and there was also no
difference between the two groups in terms of the proportion of time spent diving. At the scale of complete foraging cycles,
time taken to return to the pup was significantly longer in the treatment group but there was no difference in the rate of
delivery of energy (measured from pup growth rate) to the pups in each group. Since mothers in the treatment group did not
use significantly more body reserves, we conclude that behavioral adjustments at the scale of individual dives allowed mothers
in the treatment group to compensate for the additional foraging costs. Pup growth rate appears to be less sensitive to the
foraging conditions experienced by mothers than foraging trip duration.
Received: 14 June 1996 / Accepted after revision: 16 November 1996 相似文献
16.
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
17.
Testosterone stress does not increase asymmetry of a hormonally mediated sexual ornament in a lizard
José P. Veiga Alfredo Salvador Pilar López José Martin 《Behavioral ecology and sociobiology》1997,41(3):171-176
The theory that fluctuating asymmetry is sensitive to both environmental and genetic stress is gaining acceptance among evolutionary
biologists. Most empirical work has focused on ornamental traits on the assumption that they are more susceptible to stress.
In tegumentary coloration is a common ornament in nature, and frequently has a hormonal basis. Earlier studies in the lizard
Psammodromus algirus indicate that testosterone induces the development of head nuptial coloration in large males and, at the same time, produces
an increase of the ectoparasite load and higher mortality. Hence, the manipulation of testosterone levels may be a way to
increase ornament expression and simultaneously create conditions that may make symmetrical development difficult. This positive
covariation between character size and symmetry is opposite to that expected in theory for sexually selected traits, so the
predicted elevation of asymmetry due to the treatment cannot be confounded by any intrinsic association between symmetry and
character size. We firstly consider the effect that testosterone supplementation has on two variables that reflect the symmetry
of bilateral throat nuptial coloration in large P. algirus males. Also, we examine whether ornament symmetry is positively associated with reproductive success, a prediction of theory
of sexually selected symmetry. Testosterone treatment did not increase the fluctuating asymmetry of throat coloration. Size
asymmetry increased with character size in individuals with a fragmented colour pattern, but changed suddenly to a highly
symmetric pattern in individuals with non-fragmented coloration. Mirror asymmetry decreased steadily with character size.
These results suggest that the development of coloration on both sides of the throat midline follows a random pattern. Asymmetry
did not correlate with variables that estimated reproductive success, suggesting that asymmetry is not affected by physiological
stress and that this trait is not a sexually selected signal in P. algirus.
Received: 1 July 1996 / Accepted after revision: 4 May 1997 相似文献
18.
Janette Wenrick Boughman 《Behavioral ecology and sociobiology》1997,40(1):61-70
Individually distinctive vocalizations are ubiquitous; however, group distinctive calls have rarely been demonstrated. Under
some conditions, selection should favor calls indicating social group membership in animals that forage in groups. Greater
spear-nosed bats (Phyllostomus hastatus) give calls that appear to facilitate recognition of social group mates who are unrelated. Females give loud broadband (4–18 kHz)
vocalizations termed screech calls when departing on foraging trips and at foraging sites. Screech calls help to establish
foraging groups among social group members, and to maintain contact over the long distances they travel while foraging. I
test two hypotheses about how screech calls may be structured to convey caller identity. Individual calls may be distinct
and group members may learn to recognize each individual's calls and to associate the individual with the social group. Alternatively,
groups may give distinct calls and individuals within groups may share call characteristics. To test these hypotheses I conducted
multivariate acoustic analysis of multiple calls from 28 bats from three social groups. Although the ubiquity of individually
distinctive calls in other taxa makes this result more likely, the results reveal that group calls are highly distinctive.
Individual bats within groups are statistically indistinguishable. Calls appear to decrease slightly in frequency as bats
age. Call convergence among unrelated group mates implies vocal learning in this species.
Received: 28 March 1996 / Accepted after revision: 6 October 1996 相似文献
19.
Carola Borries 《Behavioral ecology and sociobiology》1997,41(3):139-150
In the seasonally breeding langur (Presbytis entellus) population of Ramnagar, South Nepal, where multimale groups prevail, 25 attacks on 11 infants (including one actual killing)
by seven adult males were witnessed in five groups by six observers between 1990 and 1996. Circumstantial evidence also indicates
three additional attempts at infanticide and in seven additional cases infanticide was presumed or likely. Infanticide presumably
accounted for 30.8–62.5% of infant mortality in the first 2 years of life. Most attackers (91.4%) were residents of the infants'
group and had immigrated after the infants had been born (75.0%) or conceived (25.0%). Thus, they were not related to the
victims. The interbirth interval was shortened if an infant died either prior to September of its 1st year of life (mean = 1.2
years), or its 2nd year (mean = 2.0) and even its 3rd year (mean = 2.4). All attackers remained in the group at least until
the next mating season; high-ranking males maintained their dominance rank and lower-ranking males rose in rank. Since rank
and mating success were correlated and rank and reproductive success might be correlated, all attackers had a good chance
of siring the next infant of the victims' mothers and could thus have benefited by their action. Infanticide seems to be a
male reproductive strategy at Ramnagar. Infanticide has never before been reported among seasonally breeding langurs living
at such low densities. This is also the first detailed report of infanticide as a male reproductive strategy in a seasonally
breeding primate population.
Received: 19 December 1996 / Accepted after revision: 7 June 1997 相似文献
20.
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