地熊蜂蜂群发育性状评价及其饲料花粉配比优化

【目的】为了明确熊蜂蜂群发育过程中具有代表性的性状指标及其饲料花粉最优配比。【方法】以山杏Armeniaca sibirica花粉、山柳Salix caprea花粉和油菜Brassica rapa花粉为原料,通过{3,3}混料设计得到7种配比的混合花粉,分析不同混合花粉对地熊蜂Bombus terrestris(L.)无王工蜂群的产卵前时间、幼虫拖出数、幼虫总数量、幼虫总重量、蛹总数量、蛹总重量、雄蜂出房时间、出房雄蜂数量和雄蜂出生重9个蜂群性状指标的影响,使用主成分分析对蜂群性状指标进行综合评价,并通过混料回归模型预测熊蜂蜂群饲养过程中的最优花粉配比。【结果】地熊蜂无王工蜂群发育过程的9个性状指标可以归纳为幼虫发育、蛹发育、成蜂发育、蜂群发育周期4类评价因子,其中幼虫总数量、蛹总重量、雄蜂出生重、产卵前时间和雄蜂出房时间是5个主要性状指标;以蜂群主要性状指标为评价依据,得出蜂群饲养过程中最优花粉配比:当以油菜花粉单独饲喂蜂群时蜂群产卵前时间短、幼虫总数量最多、蛹总重量最大,当山杏花粉、山柳花粉和油菜花粉以1︰1.5︰1.5比例饲喂蜂群时雄蜂出房时间最短,当山柳花粉和油菜花粉以3︰1比例饲喂蜂群时雄蜂出生重最大。【结论】明确了地熊蜂无王工蜂群发育过程中的重要性状指标和饲料花粉最优配比,为进一步研究商品化熊蜂群不同发育阶段的营养需求奠定了基础。     

Thermoregulation dynamics in commercially reared colonies of the bumblebee Bombus terrestris

Thermoregulation, that is, the active control of temperature, is key to ensure proper brood development in both wild and captive bumblebee nests. In this study, thermoregulation dynamics were assessed relative to colony age and ambient temperature using commercially reared Bombus terrestris L. (Hymenoptera, Apidae, Bombus) colonies. We observed a positive relationship between brood and nest temperatures in response to ambient temperature. Thermoregulation investment (by either brooding or fanning) was lowest at brood surface temperatures between 33 and 34 °C and ambient temperatures between 28 and 32 °C. Brood temperature was less stable and thermoregulation investment higher in younger colonies, especially at lower ambient temperatures. Furthermore, queens initiated colonies sooner and colonies developed faster when kept at an ambient temperature of 29 °C as compared to 24 °C. Our results suggest that ambient temperatures are ideally kept between 29 and 31 °C.     

Regulation of queen-worker conflict in bumble-bee (Bombus terrestris) colonies

In annual colonies of bumble-bees overt queen-worker conflict is limited to a distinct 'competition phase' (CPh). In unmanipulated Bombus terrestris colonies, the queen's switch to male production (the 'switch point', SP) accounted for only-22% of the variation in the onset of the CPh. In some colonies, the CPh even began before the SP. The CPh was more strongly correlated with the transition in queen production (r=0.79). Replacing the queen eggs with male eggs or doubling the number of workers in young colonies resulted in a significantly earlier onset of the CPh and a significantly earlier transition to queen production. Replacing queen eggs with female eggs did not have this effect. These manipulations did not affect the timing of the queen's switch from female to male production. These findings show that the mechanism underlying the queen-worker conflict in insect societies is more complex than previously appreciated. The onset of queen-worker conflict cannot be attributed simply to a single factor such as the queen's switch to male production or a decrease in queen inhibition. Rather, multiple cues are important.     

Influence of inbreeding in the early stages of artificially reared colonies of Bombus terrestris

In the present study on the bumblebee Bombus terrestris, we investigated the influence of inbreeding on queen fitness by comparing diapause survival and egg-laying success of queens mated with nestmate and non-nestmate males. We then compared the early stage of colonies with or without diploid males and analysed colony characteristics to identify a factor predictive of colony outcome. Diapause survival was no different between queens mated with nestmates and non-nestmates, but in the latter case, egg-laying success was significantly higher. Queens mated with nestmates gave rise to a percentage of diploid male colonies (52.6%) compatible with brother–sister coupling. We obtained 18.6% of colonies with diploid males even from queens mated with non-nestmates, indicating that the colonies of origin were in some way related or homozygous at the sex determination loci. There was no difference in the early growth stage between colonies with or without diploid males, except in the number of workers emerging in the first brood, which was significantly higher in the latter. Among diploid male colonies, the number of workers and the male/worker ratio in the first brood was highly variable and was not a good predictor of subsequent colony growth. Out of 49 colonies with diploid males that reached full development, only 11 had a sufficient size to assume that they could survive in the field or, in a commercial breeding, to be suitable for pollination purposes.     

A field experiment on the effect of Nosema bombi in colonies of the bumblebee Bombus terrestris

Abstract 1. Nosema bombi is a microsporidian parasite of bumblebees that is of potentially great ecological and economic importance. Nosema bombi has been shown to have detrimental fitness effects on the bumblebee Bombus terrestris under laboratory conditions. The present study investigates whether N. bombi also has negative fitness effects under natural conditions. 2. A field experiment was conducted with B. terrestris spring queens caught from the wild. In the laboratory these queens were assigned to either infected or control treatment groups. On the emergence of workers, colonies were placed in the field and a number of fitness and life‐history traits were measured. 3. The size of colonies produced by infected queens was significantly smaller than those of control queens. None of the 14 infected colonies produced sexual offspring, whereas four of the 14 control colonies reached the male production stage. Results of the field experiment are in agreement with prior laboratory‐based results, and even imply that such effects are amplified under natural conditions. 4. The evidence suggests that, on entering the colony early, N. bombi has a highly detrimental effect on the fitness of its host. It would seem that this parasite reduces its opportunities to transmit into the next host generation.     

Effects of resource availability and social parasite invasion on field colonies of Bombus terrestris

Abstract.  1. The survival, growth and fecundity of bumblebee colonies are affected by the availability of food resources and presence of natural enemies. Social parasites (cuckoo bumblebees and other bumblebees) can invade colonies and reduce or halt successful reproduction; however, little is known about the frequency of invasion or what environmental factors determine their success in the field.
2. We used 48 experimental colonies of the bumblebee Bombus terrestris , and manipulated both resource availability at the landscape scale and date of colony founding, to explore invasion rates of social parasites and their effect on the performance of host colonies.
3. Proximity to abundant forage resources (fields of flowering oilseed rape) and early colony founding significantly increased the probability of parasite invasion and thus offset the potential positive effects of these factors on bumblebee colony performance.
4. The study concludes that optimal colony location may be among intermediate levels of resources and supports schemes designed to increase the heterogeneity of forage resources for bumblebees across agricultural landscapes.     

The control of nest climate in bumblebee (Bombus terrestris) colonies: interindividual variability and self reinforcement in fanning response

Interindividual variability in response to environmental stimuliis believed to have a major impact on collective behaviors insocial insects. The present study presents a detailed investigationof the variability in individual fanning behavior underlyingthe collective control of nest climate in bumblebee (Bombusterrestris) colonies. Four colonies were repeatedly exposedto increasing temperature and CO₂ levels. The response thresholdof each worker (defined as the mean stimulus intensity at whicha worker responded by fanning) was determined. Temperature responsethresholds of 118 workers and CO₂ response thresholds of 88workers were analyzed. Workers differed in their response thresholds.Some consistently responded to low stimulus intensities, othersconsistently responded to high stimulus intensities. No consistentcorrelation between temperature and CO₂ thresholds was foundwithin individuals. Response thresholds of fanning bees decreasedover successive trials, providing empirical support for theidea of specialization through individual threshold reinforcement.In addition to variability in individual response thresholds,workers of a colony differed in two other parameters of responsiveness:response probability (the probability of responding to a stimulusonce it exceeded an individual's response threshold) and responseduration (the persistency with which fanning was performed oncean individual responded). The results of the present study suggestthat response threshold, response probability and response durationare important independent parameters of individual responsivenessin the collective control of nest climate in bumblebee colonies.     

水生动物的争胜行为

同种动物个体相遇争斗的行为称为争胜行为。这是一种典型的社会行为,广泛存在于各类水生动物中,其目的是确定优势(统治)地位和从属关系。该文针对争胜行为的表现形式、影响因素、以及发生机制进行了综述,分析了争胜行为的研究现状及发展趋势,以期为水生动物争胜行为的研究提供借鉴和参考,并为促进我国水产养殖业的发展提供理论依据。     

Agonistic displays in the rock bass,Ambloplites rupestris

Agonistic encounters between pairs of adult rick bass, Ambloplites rupestris were observed and the behaviour and changes in coloration of the dominant and subordinate individuals analysed. Dominance coloration involved the establishment of a high degree of visual contrast, whereas subordinate coloration made the animals darker and their coloration less striking, thus perhaps serving a protective function.     

Sex ratio variation in the bumblebee Bombus terrestris

Patterns of sex allocation in bumblebees have been enigmaticand difficult to interpret in either a Fisherian context orin a kin-selection perspective. We gathered data on severalhundred laboratory-reared colonies of the bumblebee Bombus terrestrisand analyzed sex allocation as a function of diapause durationand a series of variables describing colony development. Ouranalyses addressed both sex allocation patterns across differentcohorts of laboratory colonies reared at different times andsex allocation patterns across individual colonies within thesecohorts. We used path analysis to test a hypothetical modellinking a sequence of colony-development variables to the crucialreproductive parameters at the end of the colony life cycle.We show that (1) population-wide patterns of sex allocationshow equal investment in the sexes and are thus consistent withqueen control, but not with worker control. (2) A significantpart of the colony-level and cohort-specific variation in sexallocation is related to the hibernation conditions of foundingqueens: Queens with longer than average winter diapause producelarger cohorts of first and second brood workers, switch tohaploid eggs early, and produce colonies that raise mostly malesand few new queens and vice versa. (3) Colony-level sex allocationis significantly related to the time span between the switchpoint (date of first haploid egg laid by the queen) and thecompetition point (date of first haploid egg laid by one ofthe workers): the longer this period, the more male biased thesex ratio. (4) The breeding constraints of an annual life cycle,the short reproductive season, and the presumably high premiumon early produced males imply that bumblebee workers have norealistic options to capitalize on their relatedness asymmetrytoward the different kinds of reproductive brood by biasingthe sex ratio.     

Acrosome morphogenesis in Lumbricus terrestris

Summary Acrosome morphogenesis commences in the juxtanuclear cytoplasm at the posterior end of spermatids of Lumbricus terrestris. A dense rod-shaped structure and the Golgi apparatus together participate first in forming an acrosome vesicle that contains the acrosome granule, and somewhat later shape the conical base of the acrosome in the cytoplasm beneath the vesicle. Cytoplasmic flow may account for the migration of the immature acrosome to the apical surface of the nucleus of the spermatid. Manchette microtubules play a key role in the final modelling of the acrosome. Sheathed by the manchette the acrosome elongates to 3–4 times its pre-attachment length. The conical base of the acrosome then extends anteriorly to enclose the acrosome vesicle. A dense rod emerging from the rod-shaped granule occupies an indentation of the base of the acrosome vesicle. The mature acrosome of Lumbricus is an extremely complex structure about 5–7 microns long and is bounded by the plasmalemma of the spermatozoon.This study was supported by a research training grant GM-00582-07 from the Public Health Service.     

Parvalbumin-immunoreactive material in the earthworm, Lumbricus terrestris

Parvalbumin-like material was localized using an immunoeytochcmieal method, in neurons of the central nervous system and in cells intermingled in the skin of the earthworm. Lumbricus terreslris L. Parvalbumin-immunoreactive material was found in the cytoplasm of perikarya and neutrites, not in the nucleoplasm. In contrast to vertebrates, Lumbricus musculature did not contain parvalbumin-immunoreactive material.     

Interchange of Grooming and Agonistic Support in Chimpanzees

We investigated the temporal relationship between grooming given and agonistic support received in a group of chimpanzees at Chester Zoo, U.K. We compared grooming levels the day before a conflict-with-support to those the day before a conflict-without-support and to baseline to investigate whether individuals groom potential supporters in anticipation of the need for support. We also compared grooming and aggression levels the day after conflicts-with-support to levels the day after conflicts-without-support and to baseline levels to determine whether chimpanzees reward individuals that support them or punish those that do not. Finally, we compared grooming and aggression levels the day after conflicts-with-unsuccessful-solicitations-for-support to those the day after conflicts-with-support and to baseline to examine the behavioral consequences of not providing support when an individual had solicited but did not receive it. Future recipients of support groomed future supporters more the day before receiving support, compared to the day before conflicts-without-support, indicating that grooming increased the likelihood of support. The relationship between prior grooming and support held true only for aggressor and not victim support and is consistent with behavior expected if chimpanzees anticipated the need for agonistic support and groomed their supporter the day before to increase the likelihood of support. We found evidence of a system of reward and punishment. Individuals experienced significantly lower rates of aggression after conflicts in which they provided support than at baseline and after conflicts in which they did not provide support. The finding was true only for aggressor support. We found no evidence that chimpanzees punished individuals whom or that they unsuccessfully solicited with aggression or a reduction in grooming. However, solicitors groomed individuals that they solicited for support significantly more after unsuccessful solicitations than after individuals provided support (but with no difference from baseline), indicating that individuals may attempt to recement their relationship after an unsuccessful solicitation. The findings are consistent with a mechanism of calculated interchange in chimpanzees.     

Occurrence of ceramide-glycanase in the earthworm, Lumbricus terrestris

We have detected the presence of ceramide-glycanase in the earthworm, Lumbricus terrestris. We have also devised a simple method for the preparation of this enzyme from the earthworm. This enzyme cleaved the linkage between the ceramide and the glycan chain in LacCer, GbOse3Cer, GbOse4Cer, GbOse5Cer, GM3, GM2, GM1 and GD1a. By using tritium-labeled GM2 as substrate, the optimum pH of this enzyme was found to be between pH 4 and 4.5. In the earthworm, the ceramide-glycanase was mainly found in the muscle. The intestine was found to contain a very low level of this enzyme. Because of their easy availability, earthworms should become a convenient source for the preparation of ceramide-glycanase.     

Heritability of sperm length in the bumblebee Bombus terrestris

Sperm length is highly variable, both between and within species, but the evolutionary significance of this variation is poorly understood. Sexual selection on sperm length requires a significant additive genetic variance, but few studies have actually measured this. Here we present the first estimates of narrow sense heritability of sperm length in a social insect, the bumblebee Bombus terrestris. In spite of a balanced and straightforward rearing design of colonies, and the possibility to replicate measurements of sperm within single males nested within colonies, the analysis proved to be complex. Several appropriate statistical models were derived, each depending on different assumptions. The heritability estimates obtained ranged from h ² = 0.197 ± 0.091 to h ² = 0.429 ± 0.154. All our estimates were substantially lower than previous estimates of sperm length heritability in non-social insects and vertebrates.     

Sex-differences in the Agonistic Behavior of Spiny-mice (Acomys cahirinus)

Observations of 8 groups each containing three adult spiny mice (Acomys cahirinus) revealed that instances of chasing and physical displacement were quite common, while fighting and biting were rarely observed. The relationships between the most frequent behavioral categories were presented in a correlation matrix. In a second, study, ♀♀ tested in their home cages were dominant over ♂♂ In the ♂♂ home cages, however, no differences in the frequency of ♀ vs. ♂ aggression were observed. More instances of aggression were observed in the cages of the ♀♀ than in the cages of the ♂♂.