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81.
Informational constraints can be an important limitation on the accuracy of recognition. One potential constraint is the use
of recognition information from the same sources in multiple discriminatory contexts. Worker wood ants, Formica fusca, discriminate eggs based on their maternal sources of origin in two main contexts: recognition of eggs laid by nestmate versus
non-nestmate queens and recognition of worker-laid versus queen-laid eggs. We manipulated the experience of F. fusca workers in laboratory colonies to both worker-laid and queen-laid eggs by transferring eggs between colonies in order to
investigate whether these two contexts of egg discrimination are independent. Experience of non-nestmate queen-laid eggs significantly
increased worker acceptance of both familiar (18% accepted) and unfamiliar (10%) queen-laid eggs compared to control workers
without experience of eggs other than those laid by their own colony’s queen (2%). In contrast, worker acceptance of worker-laid
eggs was not affected by variation in the egg experience of workers (14% in workers from control colonies exposed only to
eggs from their own colony’s queen versus 19% and 17% in workers from colonies which had received eggs laid by either a non-nestmate
queen or nestmate workers, respectively). Our results suggest that these two recognition contexts do not strongly constrain
each other and are different in their ontogeny. In particular, worker-laid eggs are universally discriminated against by workers
from colonies with a queen whatever the egg experience of the workers, while non-nestmate queen-laid eggs are strongly discriminated
against only by workers without experience of eggs laid by more than one queen. 相似文献
82.
Foundresses of the social wasp Polistes biglumis were tested to see whether they were able to recognize alien eggs experimentally introduced into their own nests. Foundresses
removed alien conspecific reproductive-destined eggs while they accepted worker-destined eggs. The results indicate that social
wasps discriminate among eggs and that they discriminate against alien eggs destined to produce unrelated reproductives. P. biglumis is a strictly solitary founding species, with no reproductive competition within colonies; thus, brood discrimination abilities
could have evolved as a counteradaptation against intra- and inter-specific brood parasitism.
Received: 12 May 2000 / Revised: 15 July 2000 / Accepted 20 July 2000 相似文献
83.
The social environment of many species includes synchronous maturation of siblings in family groups, followed by limited dispersal
of adults from their natal site. Under these conditions, females may experience high encounter rates with same-age siblings
during mate searching, increasing their risk of inbreeding. If inbreeding depression occurs, mating with a sibling is often
considered maladaptive; however, in some contexts, the inclusive fitness benefits of inbreeding may outweigh the costs, favoring
females that tolerate some level of inbreeding depression. We evaluated mating patterns in the treehopper Umbonia crassicornis, a semelparous species in which females encounter same-age siblings during mate searching. A female U. crassicornis that mates with a brother suffers from inbreeding depression. We used a free-choice mating design that offered females simultaneous
mating opportunities with three groups of males: siblings, same-age nonsiblings, and older nonsiblings. These groups represent
the types of males typically encountered by females during mate searching. Our goal was to assess whether mating patterns
were influenced by inbreeding avoidance by evaluating two hypotheses: kin discrimination and age-based mating (older males
cannot be siblings in this species). There was no difference in the proportions of females mating with siblings vs nonsiblings,
suggesting an absence of kin discrimination. However, females mated with a greater proportion of older vs younger males. Given
that females do not avoid siblings as mates despite a cost to inbreeding, our results provide a possible example of inbreeding
tolerance. We also discuss some factors that may have contributed to the mating advantage of older males. 相似文献
84.
Learning is generally predicted not to be important in host discrimination by parasitoids, because the stimuli involved are
less variable than those used in habitat location. However, Anaphes victus (Hymenoptera: Mymaridae), an egg parasitoid of Listronotus oregonensis (Coleoptera: Curculionidae) apparently learns to associate external pheromones with the presence of a conspecific in a host.
In this species, females can reject a parasitized host either after antennal drumming (antennal rejection) or after the insertion
of their ovipositor (sting rejection). When they encountered a series of parasitized hosts, females A. victus learned to associate the presence of the external pheromone with the presence of the internal one. Learning lasted less than
4 h and occurred earlier in a series when the female marking the egg and the one detecting that mark were close relatives.
This behavior could be adaptive because antennal rejection is faster than sting rejection.
Received: 11 March 1997 / Accepted after revision: 30 August 1997 相似文献
85.
Assisting the genetic parents in the rearing of young, a widespread phenomenon in many birds and mammals, is usually regarded
as an altruistic or mutualistic behavior. Infant handling by females other than the mother is also common in many primates,
but due to high within- and between-species variation and limited knowledge about fitness consequences there is no consensus
about its evolutionary and functional significance. Analysis of female infant-handling patterns and its reproductive consequences
in three groups of semifree-ranging Barbary macaques revealed that nulliparous females significantly more often handled infants
than parous females, but infant handling experience did not affect survival of their own first live-born offspring. Females
interacted preferentially with closely related infants, but infant handling frequency improved neither infant survival nor
maternal fecundity. Reciprocation of infant handling by mothers was rare. Although “aunting to death” occurred in the population,
the hypothesis that infant handling serves to reduce the fitness of competitors was not supported. Limited evidence suggests
that females at least sometimes use infants as strategic tools in the course of alliance formation. In concert with this poor
evidence for a functional basis of the behavior, several lines of evidence support the hypothesis that infant handling evolved
as a non-adaptive by-product of a strong selection for mother-offspring bonding. (1) Rates of infant handling were highest
among females that experienced early infant loss. (2) Females caring for infants or yearlings of their own handled other infants
significantly less often than females without dependent offspring. (3) Infant handling by females was most prevalent during
the infants’ first month of life. (4) Both “aunting to death” and a successful adoption occurred irrespective of kinship relations.
Although the by-product hypothesis appears to be the only one able to explain all results of this study, the apparent rarity
of infant handling in non-female-bonded species suggest that kin selection is a possible alternative explanation for the evolution
of female infant-handling in primates.
Received: 30 December 1995/Accepted after revision: 10 May 1996 相似文献
86.
在采用未确知聚类评价模型进行多指标分级评价时,常采用置信度识别准则作为待测对象的属性识别,该准则中置信度的取值由人为取定,当置信度取值不同时,得到的分级判定结果往往出现差异,甚至产生完全不同的判定结果。通过距离判别的思想将未确知聚类理论中的置信度识别准则进行改进,并运用到岩爆烈度的分级预测中。根据岩爆发生的主要影响因素,选取岩石单轴抗压强度σ_c、单轴抗拉强度σ_t、最大切应力σ_θ及岩石的弹性变形能指标W_(et)为岩爆主要影响因子。并以σ_c/σ_1、σ_θ/σ_c、W_(ey)为岩爆烈度等级评价因子,建立未确知测度模型,以距离判别改进后的属性识别方法进行分级预测,并与原置信度识别准则得到的判别结果进行分析和比较。为验证改进模型的实用性,以贵州开磷集团马路坪矿区为例,采用改进的未确知聚类模型对其岩爆烈度等级进行预测分析。结果表明,预测结果与实际情况基本吻合,证明采用改进后的未确知测度模型的判别结果不仅消除了由于置信度取值不同造成的判别结果误差,降低了人为主观因素的影响,而且具有较高的判别准确性和可行性。 相似文献
87.
《组织行为杂志》2017,38(1):124-151
The Workplace Intergenerational Climate Scale (WICS) is designed to measure employees' attitudes and perceptions about workers of different ages in the workplace. In Study 1, an initial 18‐item measure was developed, reflecting five subscales: Intergenerational Contact, Workplace Intergenerational Retention, Positive Intergenerational Affect, Workplace Generational Inclusiveness, and Lack of Generational Stereotypes. Scores on the five WICS subscales were linked to workplace mentoring, opinions about older workers, and job satisfaction. In Study 2, the WICS items and subscales were further refined, and subscale relationships with similar constructs were explored via structural equation modeling. In Study 3, a more occupationally diverse sample was used to support criterion, incremental, discriminant, and external validity. Evidence supports the use of the WICS as a valid and reliable multidimensional measure of an organization's intergenerational climate. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
88.
Leonardo?DapportoEmail author Cristina?Pansolli Stefano?Turillazzi 《Behavioral ecology and sociobiology》2004,56(4):315-321
Various studies indicate that cuticular hydrocarbons (CHCs) act as cues for nestmate recognition in paper wasps and other social insects. A recent study showed that associative nest foundation in Polistes dominulus is mainly performed by foundresses coming from the same locality. In the present study, we induced future foundresses of P. dominulus collected in two different localities to hibernate in the laboratory in aggregates of individuals from the same or different localities. After 2 months of hibernation, foundresses from different localities but from the same experimental cluster did not show any preference to associate, at the time of nest foundation, with individuals coming from the same original locality. The cuticular chemical profiles of individuals from the mixed hibernation clusters were quite similar and significantly different from those of individuals which hibernated with other foundresses from the same locality. These findings suggest that, in this species, mechanisms other than nestmate chemical recognition play a major role in the spring association of gynes during the foundation of a new nest.Communicated by R.F.A. Moritz 相似文献
89.
No evidence for the work-conflict hypothesis in the eusocial naked mole-rat (Heterocephalus glaber ) 总被引:1,自引:0,他引:1
The work-conflict hypothesis (Reeve 1992) postulates that in eusocial naked mole-rat (Heterocephalus glaber) colonies there is potential conflict between the breeding female and her non-breeding colony mates over how much aid they
provide in support of her reproduction. Non-breeders may withhold aid either because they are hopeful reproductives and/or
because they have less to gain in terms of inclusive fitness. Breeding females should, therefore, preferentially direct aggression
in the form of shoving (prolonged pushes usually involving nose-to-nose contact) towards large (hopeful reproductives) and
less related non-breeders to incite them to provide aid. This study tested the following predictions of the work-conflict
hypotheses. (1) There is kin bias in the shove rate of breeding females and work rates of non-breeders; (2) Shoving activates
work in non-breeders. We found no evidence to suggest that the breeding female shove rate and the amount of colony maintenance
activities performed by non-breeders is influenced by relatedness. Body size was a better predictor of work rate and shove
rate; large animals were shoved more and worked less. Furthermore, shoving did not affect the work rate of non-breeders and
rarely incited activity in inactive mole-rats. Individual mole-rats were also more likely to be shoved when already active
than when resting in the nest. These results suggest that shoving by the breeding female may have functions other than the
incitement of activity, such as the reproductive suppression of non-breeders.
Received: 17 January 1996 / Accepted after revision: 21 September 1996 相似文献
90.
Sofia?A.?Wahaj Russell?C.?Van Horn Toni?L.?Van Horn Rachel?Dreyer Ryan?Hilgris Jessica?Schwarz Kay?E.?HolekampEmail author 《Behavioral ecology and sociobiology》2004,56(3):237-247
We examined patterns of affiliation, association, and aggression to inquire whether spotted hyenas (Crocuta crocuta) can distinguish among various groups of maternal and paternal siblings. If so, and if these animals conform to predictions of kin selection theory, then behavioral interactions among hyenas should vary with relatedness. We also considered familiarity-based recognition and phenotype matching as mechanisms hyenas might use to recognize kin. Patterns of affiliative behavior indicated that hyenas favored full-sibling littermates over half-sibling littermates or any other group of half-siblings. Rates of dyadic aggression generally did not vary with kinship. Hyenas associated more closely with half-sibling littermates than with non-littermate half-siblings, and hyenas affiliated more with maternal half-siblings than with paternal half-siblings, suggesting that familiarity-based cues might mediate discrimination among these sibling classes. In addition, operation of a phenotype-matching mechanism was suggested by the preference hyenas demonstrated during affiliative interactions for full- over half-sibling littermates, and by their lack of preference in these interactions for half-sibling littermates over non-littermate half-siblings. Phenotype matching was also suggested by our observation that paternal half-siblings cooperated more, and fought less, than did non-kin. Our data indicate that hyenas can discriminate among various types of siblings, that their social behavior conforms to predictions of kin selection theory, and that they recognize kin using mechanisms of both familiarity and phenotype matching.Communicated by S. Alberts 相似文献