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1.
Previous experiences can play a significant role in determining future behaviors. Winner and loser effects, where the outcome
of previous aggressive encounters influences the behavioral approach to and outcomes of future conflicts, have been documented
in many taxa and illustrate this phenomenon. These effects are prevalent in species that interact frequently because modulation
of these potentially costly social interactions may influence fitness. Stalk-eyed flies of the dimorphic species Teleopsis dalmanni engage in frequent fights over food resources, as well as over access to harems of females, with larger males typically prevailing
when size disparities exist. However, whether and how prior experience influences fighting decisions and outcomes remains
unexplored. To test for winner and loser effects in stalk-eyed flies, sexually mature flies were paired in size-mismatched
dyads to establish winning and losing experiences. After their first contest, the flies were paired with size-matched individuals
and allowed to interact. We determined whether an initial winning or losing experience significantly altered the outcome probabilities
in the second size-matched encounter. Initial winning experience did not significantly affect the second interaction, providing
no evidence for a winner effect. However, initial losers were significantly more likely to lose a subsequent interaction which
provides evidence for a loser effect in stalk-eyed flies. In addition, smaller males experienced an increased probability
of losing their second interaction regardless of prior winning or losing experience. This effect was not seen in large males.
Our data suggest that the loser effects we observed, which were more pronounced in small males, could result from the energetic
costs of fighting that they were less able to absorb than large males. 相似文献
2.
The elongated eye span of male Diopsid flies is a sexually selected character that scales positively with body size. Previously,
the duration of agonistic contests was found to increase as rival body size and eye span disparities decreased. Hence, along
with its role in mate choice, eye span seems to facilitate mutual assessment of rival size. However, such results are also
expected in the absence of rival assessment, when each individual persists according to its own size-dependent internal threshold.
Here, we reanalyze these contests to distinguish between these two hypotheses using two measures of size: body length and
eye span. Mutual assessment predicts that contest duration should increase with loser size and decrease with winner size.
In contrast, our results were more consistent with self-assessment: We found a positive relationship between loser size and
contest duration, whereas winner size did not affect contest duration. Thus, flies did not appear to assess the size of their
rivals, indicating that the mutual assessment function of eye span elongation may be less important than previously suspected.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Camila Zatz Rachel M. Werneck Rogelio Macías-Ordóñez Glauco Machado 《Behavioral ecology and sociobiology》2011,65(5):995-1005
Intense male–male competition for females may drive the evolution of male morphological dimorphism, which is frequently associated
with alternative mating tactics. Using modern techniques for the detection of discontinuous allometries, we describe male
dimorphism in the Neotropical harvestman Longiperna concolor, the males of which use their elongated, sexually dimorphic legs IV in fights for the possession of territories where females
lay eggs. We also tested three predictions related to the existence of alternative mating tactics: (1) if individuals with
relatively longer legs IV (majors) are more likely to monopolize access to reproductive resources, they are expected to remain
close to stable groups of females more than individuals with relatively shorter legs IV (minors) do; (2) if minors achieve
fertilization by moving between territories, they are expected to be less faithful to specific sites; and (3) majors should
be observed in aggressive interactions more often. We individually marked all the individuals from a population of Longiperna during the reproductive season and recorded the location of each sighting for males and females as well as the identity of
males involved in fights. Majors were more likely to have harems, and large majors were even more likely to do so. Majors
were more philopatric and all males involved in fights belonged to this morph. These results strongly suggest that the mating
tactic of the majors is based on resource defense whereas that of the minors probably relies on sneaking into the territories
of the majors and furtively copulating with females. 相似文献
4.
Kevin J. Delaney J. Andrew Roberts George W. Uetz 《Behavioral ecology and sociobiology》2007,62(1):67-75
Male signaling behaviors are often studied in a single context but may serve multiple functions (e.g., in male–male competition
and female mate choice). We examined the issue of dual function male signals in a wolf spider species Schizocosa ocreata (Hentz) that displays the same species-specific signaling behaviors in both male–male and male–female contexts. These signaling
behaviors have been described as either aggression or courtship according to the context observed. We tested the possibility
of dual functions by comparing the relationship between behaviors and outcome of male–male contests (winner/loser) and male–female
mating encounters (mating success). Frequency, rate, and mean duration of signaling behaviors did not vary with outcome of
male–male contests, which appears instead to be based upon relative size and body mass. Winners of contests had significantly
greater body mass than losers, and greater mass relative to opponents was significantly associated with probability of winning.
Overall, signaling rates were much higher in male–female interactions than in male–male contests and were higher for males
that successfully mated than for those that did not mate. Mean duration of some male displays was also greater for males that
successfully mated. However, male size was not associated with probability of mating. Taken together, results suggest an intersexual
selection context for the current function of male signals in these wolf spiders and that increased display vigor is associated
with male mating success. 相似文献
5.
Reproductive trade-offs from mating with a successful male: the case of the tephritid fly Anastrepha obliqua 总被引:2,自引:1,他引:1
Diana Perez-Staples Martín Aluja Rogelio Macías-Ordóñez John Sivinski 《Behavioral ecology and sociobiology》2008,62(8):1333-1340
In lekking species, females may become sperm-limited when mating with sexually successful males, and this may be exacerbated
by a poor male diet. Polygynous males may also be limited by the amount of accessory gland products (AGPs) they can transmit
to females, which in turn may influence the females’ refractory period and longevity. Here, we tested the effect of male mating
history, larval and adult diet on copula duration, mating intervals, female fecundity, fertilisation success, life span and
likelihood to remate using sexually successful males of the lekking tephritid fly Anastrepha obliqua. Flies originated from either a native or exotic host fruit and were protein-fed or deprived. Male diet and larval host influenced
copula duration, while the time elapsed between matings was affected by the interaction of mating order and male adult diet.
Female fecundity was not influenced by female position in mating order or protein inclusion into the male diet. However, mating
order and male larval diet influenced female fertilisation success. Importantly, as males mated successively they were less
able to induce a refractory period on females, as the last females to mate with a male were more likely to remate and had
slightly longer life spans than the first females to mate with males. These results might be attributed to a decrease in male
AGPs with increasing male mating frequency. We discuss the role of conditional expression of male mating frequency with respect
to A. obliqua’s life history, the trade-off that females face when mating with a successful male, the effect of larval diet on adult sexual
performance and the possibility for sexual conflict to occur due to high male mating rates and fitness costs to females. 相似文献
6.
Leeann T. Reaney Jean M. Drayton Michael D. Jennions 《Behavioral ecology and sociobiology》2011,65(2):217-225
Body size strongly predicts fighting behaviour and outcome in many species, with the larger opponent usually winning contests. However, recent fighting experience can have a strong influence on the establishment of dominance hierarchies, with recent winners being more likely to win subsequent contests, while recent losers are more likely to lose. Recent fighting experience therefore has the potential to modify the effect of body size in determining contest behaviour and outcome. Here, we investigate whether recent fighting experience weakens the role of body size in predicting contest behaviour in the black field cricket, Teleogryllus commodus. We compared the role of body size in determining contest outcome during initial non-physical encounters and escalated aggressive physical encounters (grapples), as well as the probability of escalation occurring, in contests involving either a naïve or experienced smaller male against a naïve larger male. We found that recent fighting experience only affected contest outcome during non-physical encounters. Once a contest had escalated into grappling, the effect of previous wins and losses was no longer apparent and body size strongly predicted contest outcome. Thus, once males can directly assess their opponent's fighting ability, recent fighting experience did not alter the effect of body size on contest behaviour and outcome. 相似文献
7.
Randy Thornhill 《Behavioral ecology and sociobiology》1992,30(5):357-363
Summary Fluctuating asymmetry (FA) is defined as small, random deviations from bilateral symmetry in a generally perfect bilaterally symmetrical morphological trait. FA in forewing length affects the outcomes of interspecific contests for food items (dead arthropods) between two species of Japanese scorpionflies, Panorpa nipponensis and P. ochraceopennis, in nature. FA differences between same-sex contestants are more important than either body size or ownership of food in determining the outcomes of interspecific contests; for both sexes, winners statistically significantly more often have relatively low FA. Two condition-dependent mating tactics are used by the males of each species: (a) a male may defend a dead-arthropod nuptial gift, or (b) a male without such an arthropod may wait near a male with one. In both tactics, males release long-distance sex pheromones. Groups of pheromone-releasing males are made up of one male with a nuptial gift and his satellites; the males in a group may be conspecifics or heterospecifics. Males that lose contests for nuptial gifts often become satellites of the contest winners whether or not winners are conspecific. Satellite males have statistically significantly greater FA than males with nuptial gifts in heterospecific male display groups. Satellite males mate infrequently and briefly compared to resource-holding males. Satellites of heterospecific males copulate with conspecific females displaced from nuptial gifts by the resource-holding males of the other species. In both species, the largest and smallest individuals have the greatest FA, and intermediate-sized individuals have the least; this same pattern often occurs in other animals. 相似文献
8.
Understanding the mechanisms and determinants of conflict resolution is of great theoretical and practical importance because
the outcome of contests between males over limited resources such as mates, territories, and food has profound fitness consequences.
Despite the large literature on the theory of conflict resolution, relatively few empirical studies explicitly test predictions
related to contest structure for these models. In sexually dimorphic species of stalk-eyed flies (Diopsidae), males engage
in characteristic aggressive interactions over both females and food resources. We used sequential analysis of aggressive
interactions between dyads of male stalk-eyed flies to investigate patterns of escalation, behavioral matching, and physical
contact in order to distinguish between three common models of conflict resolution: the sequential assessment model, the cumulative
assessment model, and the energetic war of attrition. Stalk-eyed flies were shown to engage in both low- and high-intensity
behaviors during interactions with patterns of escalation and no de-escalation. Aggressive interactions did not demonstrate
behavioral matching between winners and losers. Stalk-eyed flies also escalated to behaviors that included physical contact
without injuries. Our results provide support for the sequential assessment model based on patterns of escalation with no
de-escalation, behavioral mismatching, and behaviors which include physical contact but no injuries. 相似文献
9.
A. D. Tucker H. I. McCallum C. J. Limpus K. R. McDonald 《Behavioral ecology and sociobiology》1998,44(2):85-90
We compared natal dispersals of freshwater crocodiles (Crocodylus johnstoni) against the prediction of male dispersal bias for a polygynous mating system. The crocodiles inhabited a linear series of
pools and we calculated the net distances from natal pools to recapture locations some 12–18 years later, at maturity. Philopatry
was assessed in terms of adult social distances. A female social distance was 0.46 pools and a male social distance was 1.0
pool. By these criteria, both sexes showed low levels of philopatry (7–12%). However, individuals of both sexes dispersed
from the natal site long before they were sexually mature. Divergence in dispersal patterns by sex occurred after the maturity
threshold, as males dispersed two to three times farther than females. Intrasexual competition by males is resolved by a size-based
hierarchy. The displacement of small males from local mating access is a probable cause of the longer dispersals undertaken
by males. Competition, rather than inbreeding avoidance, is driving dispersal in this population of freshwater crocodiles.
Received: 8 May 1998 / Accepted after revision: 26 June 1998 相似文献
10.
Although external sexually dimorphic traits are commonly found in males of combtooth blenny species, little is known about
the benefit they can convey to male mating success. Indeed, while female preferences for large males have been demonstrated
in some species, the possible role played by dimorphic ornaments has been neglected. We now report on the tentacled blenny,
Parablennius tentacularis, a species where males are characterized by bulb glands on the anal fin and both sexes exhibit a dark spot on the dorsal
fin and orbital tentacles. Males are territorial, make nests in empty bivalve shells, and provide solitary parental care for
the eggs. Using morphometric analysis and field collected data on male and female external features, nest characteristics
and number of eggs in the nests, we have assessed the development of dimorphic traits in both sexes and male mating success.
The results reveal that orbital tentacles of males are more developed and more variable in size than those of females. Larger
males exhibit longer orbital tentacles and larger anal glands but do not necessarily occupy larger nests. Male mating success
is significantly correlated with the inner nest surface area and with orbital tentacle size but not with body size. These
results provide support for a primary role of male ornaments in enhancing blenny male mating success and are discussed in
the context of mate choice for direct and indirect benefits. 相似文献
11.
Andrew E. Derocher Magnus Andersen Øystein Wiig Jon Aars 《Behavioral ecology and sociobiology》2010,64(6):939-946
We assessed the role of size, mass, and age in mating and non-mating polar bears (Ursus maritimus) at Svalbard, Norway, during the spring breeding season. The ratio of male to female mass, in male-female pairs, ranged from
1.00 to 3.02 ([`(x)] = 1.99 \overline x = 1.99 ) indicating that mating males were larger than mating females but with substantial variation. Paired males were older than
unpaired males and male mass was related to age. However, males paired with females were not significantly different in body
mass from those males caught alone. Wounds and scars resulting from fights between males began at about 6 years of age and
peaked at about 17 and 20 years of age, respectively. The frequency of broken canines in males, presumably due to increased
male-male conflicts, increased with age but showed little increase in females. The wide range of male size in male-female
pairs and the age-related signs of injury suggest that male polar bears engage in both scramble competition and contest competition
for access to breeding females. The mating system of polar bears is variable but is best described as female defense polygyny
or serial monogamy. 相似文献
12.
We provide evidence that male lizards can use chemosensory cues to identify individual females and probably therefore maintain
long-term associations with these females in the wild. In the laboratory, males preferentially followed the scent trail of
their vitellogenic female “partner” rather than that of another vitellogenic female. Our 5-year field study of the small viviparous
scincid lizard (Niveoscincus microlepidotus) in alpine Tasmania showed that sexually mature males and females commonly formed “pairs” for long periods (on average 29 days).
These pairs occurred primarily during the mating season, always involved one adult male and one adult female, and usually
involved vitellogenic rather than gravid females. Our laboratory experiments suggest that a significant factor in maintaining
those prolonged partnerships is male scent trailing of partners.
Received: 28 October 1997 / Accepted after revision: 28 May 1998 相似文献
13.
Kevin A. Judge Janice J. Ting Jonathan Schneider Mark J. Fitzpatrick 《Behavioral ecology and sociobiology》2010,64(12):1971-1979
Both resource-holding potential (RHP) and experience in aggressive contests are known to affect future aggressive behaviour. However, few studies have examined the effects of mating experience on agonistic behaviour, despite the fact that dominant males usually acquire more matings. We investigated the effect of mating experience on male aggressive behaviour including the relationship between RHP and fighting success in the fall field cricket, Gryllus pennsylvanicus. We formed pairs of size- and age-matched males that varied in RHP (relative weapon size) and conducted two experiments. In the first, we varied male mating experience by allowing one male in a pair to either be (a) ‘mated’: court, be mounted and copulate with a virgin female or (b) ‘experienced’: court, be mounted, but prevented from copulating. The second experiment varied postcopulatory experience where the male was allowed (‘contact’) or prevented from (‘no-contact’) continued contact with his recent mate. Following treatment, experimental males engaged in an aggressive contest with the naïve size- and age-matched male. In our first experiment, we found that mated and experienced males were equally likely to escalate contests to combat with a naïve opponent, but mated males were less likely than experienced males to win. There was no effect of mating on the relationship between RHP and fighting success. In our second experiment, we found no effect of maintaining contact with the female on the tendency to escalate or the probability of winning. As in the first experiment, males with relatively larger heads again won more fights and this relationship was unaffected by male experience. These results suggest that mating is itself detrimental to male success in aggressive contests, but that this effect is not sufficient to eliminate the effect of RHP on fighting success. 相似文献
14.
Parental investment, potential reproductive rates, and mating system in the strawberry dart-poison frog, Dendrobates pumilio 总被引:1,自引:0,他引:1
We studied the effect of relative parental investment on potential reproductive rates (PRRs) to explain sex differences in
selectivity and competition in the dart-poison frog Dendrobates pumilio. We recorded the reproductive behavior of this species in a Costa Rican lowland rainforest for almost 6 months. Females spent
more time on parental care than males, and `time out' estimates suggest that PRRs of males are much higher than than those
of females, rendering females the limiting sex in the mating process. Males defended territories that provide suitable calling
sites, space for courtship and oviposition, and prevent interference by competitors. Male mating success was highly variable,
from 0 to 12 matings, and was significantly correlated with calling activity and average perch height, but was independent
of body size and weight. Estimates of opportunity for sexual selection and variation in male mating success are given. The
mating system is polygamous: males and females mated several times with different mates. Females were more selective than
males and may sample males between matings. The discrepancy in PRRs between the sexes due to differences in parental investment
and the prolonged breeding season is sufficient to explain the observed mating pattern i.e., selective females, high variance
in male mating success, and the considerable opportunity for sexual selection.
Received: 9 June 1998 / Received in revised form: 27 March 1999 / Accepted: 3 April 1999 相似文献
15.
To understand the evolution of weapons, we must understand both their functions and relative importance compared to body size
in determining fighting success. Many decapod crustaceans develop disproportionately large chelipeds for their body size and
use them as a weapon in agonistic interaction. There are, however, examples where weapons are merely signals of resource holding
potential (RHP) and the RHP is actually determined by body size. We investigated the function and relative efficacy of body
size and major cheliped size in male–male contests for females in the hermit crab Diogenes nitidimanus. Contests over females took two forms: (1) males preemptively guarded females and opponents did not fight with the guarding
male. Cheliped size contributed significantly to the settlement of these contests and probably functioned as a visual signal
for the opponents. (2) Guarding males engaged in physical combat with an opponent. In these cases, both body and cheliped
sizes affected contest outcomes. The effect size for cheliped size was as strong, or stronger, than that for body size. These
results suggest that large chelipeds have evolved as a true weapon and are effective in escalated fights for resources. Therefore
they are also efficient visual signals for settling contests with only display. Our results are a rare example that clearly
demonstrate that weapons are a more important determinant of fights than body size when both body and weapon size affect resource
acquisition. 相似文献
16.
Katrin Brauch Keith Hodges Antje Engelhardt Kerstin Fuhrmann Eric Shaw Michael Heistermann 《Behavioral ecology and sociobiology》2008,62(9):1453-1466
In a wide variety of species, male reproductive success is determined by contest for access to females. Among multi-male primate
groups, however, factors in addition to male competitive ability may also influence paternity outcome, although their exact
nature and force is still largely unclear. Here, we have investigated in a group of free-ranging Barbary macaques whether
paternity is determined on the pre- or postcopulatory level and how male competitive ability and female direct mate choice
during the female fertile phase are related to male reproductive success. Behavioural observations were combined with faecal
hormone analysis for timing of the fertile phase (13 cycles, 8 females) and genetic paternity analysis (n = 12). During the fertile phase, complete monopolisation of females did not occur. Females were consorted for only 49% of
observation time, and all females had ejaculatory copulations with several males. Thus, in all cases, paternity was determined
on the postcopulatory level. More than 80% of infants were sired by high-ranking males, and this reproductive skew was related
to both, male competitive ability and female direct mate choice as high-ranking males spent more time in consort with females
than low-ranking males, and females solicited copulations mainly from dominant males. As most ejaculatory copulations were
female-initiated, female direct mate choice appeared to have the highest impact on male reproductive success. However, female
preference was not directly translated into paternity, as fathers were not preferred over non-fathers in terms of solicitation,
consortship and mating behaviour. Collectively, our data show that in the Barbary macaque, both sexes significantly influence
male mating success, but that sperm of several males generally compete within the female reproductive tract and that therefore
paternity is determined by mechanisms operating at the postcopulatory level. 相似文献
17.
We examined the mating behaviour of the New Zealand ocypodid crab Macrophthalmus hirtipes in the laboratory between February and June 1998. This species has a discrete breeding season. Mating and moulting were not
linked and only intermoult females with mobile gonopore opercula were attractive to males. Allometry and compatibility of
gonopods and gonopores of different-sized crabs was investigated. Under laboratory conditions, the opercula of intermoult
females remained mobile on average for 11.4 d, but the duration of receptivity did not appear to be under female control.
The operational sex ratio in the laboratory fluctuated greatly, but was always male-dominated. During the period of opercular
mobility, females mated many times with several different males. Matings in the absence of burrows were relatively short (mean
duration = 23 min, max. = 122 min) and the mating behaviour of M. hirtipes lacked courtship and mate-guarding. Males used a search-intercept method to acquire mates, with very low levels of intrasexual
competition. There was no evidence of mate preference in M. hirtipes, and males spent just as long mating with ovigerous females as with non-ovigerous ones. Although M. hirtipes has ventral-type spermathecae, as do several other ocypodid crabs, it is unclear whether this promotes last-male sperm precedence.
The role of burrows in modifying the mating behaviour of M. hirtipes in the field remains to be established.
Received: 7 January 2000 / Accepted: 5 June 2000 相似文献
18.
Functions of the major cheliped in pagurid hermit crabs have been studied in fights for shells. The major cheliped often shows
sexual size dimorphism, suggesting that sexual selection favors the development of the male major cheliped. The function of
the major cheliped in male–male competition was examined in Pagurus nigrofascia collected from April to June 2009 on the intertidal rocky shore in southern Hokkaido, Japan (41°N, 140°E). Sexual size dimorphism
of the major cheliped was observed, and precopulatory guarding males had larger major chelipeds than solitary ones. Guarding
males used the major cheliped to deter intruders during competitive interactions. Males without a major cheliped were disadvantaged
even if they were larger than opponents and had ownership. Cheliped size affected the outcomes of contests between similar
sized males. This suggests that the male major cheliped in P. nigrofascia protects mates from competitors and, consequently, enhances male mating success. Sexual selection may favor the development
of the major cheliped in male pagurids. 相似文献
19.
The genetic mating system of a sex-role-reversed pipefish (Syngnathus typhle): a molecular inquiry 总被引:4,自引:0,他引:4
Adam G. Jones Gunilla Rosenqvist Anders Berglund John C. Avise 《Behavioral ecology and sociobiology》1999,46(5):357-365
In the pipefish Syngnathus typhle as in other species of Syngnathidae, developing embryos are reared on the male's ventral surface. Although much laboratory
research has been directed toward understanding sexual selection in this sex-role-reversed species, few studies have addressed
the mating behavior of S. typhle in the wild, and none has capitalized upon the power of molecular genetic assays. Here we present the first direct assessment
of the genetic mating system of S. typhle in nature. Novel microsatellite loci were cloned and characterized from this species, and employed to assay entire broods
from 30 pregnant, field-captured males. Genetic analysis of 1340 embryos revealed that 1–6 females (mean = 3.1) contributed
to each brooded clutch, the highest rate of multiple maternity yet documented in any pipefish. Evidence of multiple mating
by females was also detected. Thus, this population of S. typhle displays a polygynandrous mating system, a finding consistent with previous field and laboratory observations. Our results,
considered together with similar studies of other syngnathid species, provide preliminary support for the hypothesis that
the genetic mating system is related to the evolution of sexual dimorphism in the fish family Syngnathidae.
Received: 19 January 1999 / Received in revised form: 15 April 1999 / Accepted: 9 May 1999 相似文献
20.
Alternative reproductive tactics and male-dimorphism in the horned beetle Onthophagus acuminatus (Coleoptera: Scarabaeidae) 总被引:6,自引:0,他引:6
Douglas J. Emlen 《Behavioral ecology and sociobiology》1997,41(5):335-341
Adult dung beetles (Onthophagus acuminatus) exhibit continuous variation in body size resulting from differential nutritional conditions experienced during larval development.
Males of this species have a pair of horns that protrude from the base of the head, and the lengths of these horns are bimodally
distributed in natural populations. Males growing larger than a threshold body size develop long horns, and males that do
not achieve this size grow only rudimentary horns or no horns at all. Previous studies of other horned beetle species have
shown that horned and hornless males often have different types of reproductive behavior. Here I describe the mating behaviors
of the two male morphs of O. acuminatus during encounters with females. Females excavate tunnels beneath dung, where they feed, mate and provision eggs. Large, horned
males were found to guard entrances to tunnels containing females. These males fought with all other males that attempted
to enter these tunnels. In contrast, small, hornless males encountered females by sneaking into tunnels guarded by other males.
In many instances, this was accomplished by digging new tunnels that intercepted the guarded tunnels below ground. Side-tunneling
behavior allowed sneaking males to enter tunnels beneath the guarding male, and mate with females undetected. Both overall
body size and relative horn length significantly affected the outcome of fights over tunnel ownership. These results suggest
that alternative reproductive tactics may favor divergence in male horn morphology, with long horns favored in males large
enough to guard tunnels, and hornlessness favored in smaller males that adopt the “sneaking” behavioral alternative.
Received: 12 October 1996 / Accepted after revision: 8 August 1997 相似文献