ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    ISSN: 1432-0762
    Keywords: Key words Polyandry ; Multiple mating ; Apis ; Behavioral dominance ; Microsatellites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using four polymorphic microsatellite loci, we found that four Apis andreniformis queens collected in Thailand each mated at least 10–20 times, producing an average relatedness, g ww, of workers of 0.30 ± 0.007, and an average effective number of matings of 9.1 ± 2.2. The degrees of polyandry and intra-colonial genetic relatedness in A. andreniformis are similar to those in A. mellifera, slightly more than in A. florea, and up to 6 times less than in A. dorsata. We argue that while presently favoured hypotheses for the evolution of polyandry in monogynous social insects may adequately explain the evolution of up to five or six matings, they are inadequate to explain the extreme polyandry (10–60 matings) observed in Apis. One alternative possibility is that colony fitness is a non-additive function of the fitness of individual subfamilies. Such behavioral over-dominance may mean that queen fitness is increased by high levels of polyandry, which increase the probability of desirable combinations of worker genotypes occurring in one colony. The special attributes of honey bees which may lead to behavioral over-dominance include colony aggregation (which may increase the incidence of disease), and frequent long-distance migration.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1432-0762
    Keywords: Key words Worker policing ; Laying workers ; Anarchy ; Apis mellifera ; Kin selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  In anarchistic honey-bee colonies, many workers’ sons are reared despite the presence of the queen. Worker-laid eggs are normally eaten by other workers in queenright colonies. Workers are thought to discriminate between queen-laid and worker-laid eggs by the presence or absence of a queen-produced egg-marking pheromone. This study compared the survival of three classes of eggs (worker-laid eggs from anarchistic colonies, worker-laid eggs from non-anarchistic queenless colonies, and queen-laid eggs) in both queenright normal colonies and queenright anarchistic colonies, in order to test the hypothesis that anarchistic workers evade policing by laying more acceptable eggs. As expected, few worker-laid eggs from non-anarchistic colonies survived more than 2 h. In contrast, worker-laid eggs from anarchistic colonies had much greater acceptability, which in some trials equalled the acceptability of queen-laid eggs. Anarchistic colonies were generally less discriminatory than normal queenright colonies towards worker-laid eggs, whether these originated from anarchistic colonies or normal queenless colonies. This indicates that the egg-removal aspect of the anarchistic syndrome involves both worker laying of eggs with greater acceptability and reduced discriminatory behaviour of policing workers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2014-03-22
    Description: The epigenetic mark of DNA methylation, the addition of a methyl (CH 3 ) group to a cytosine residue, has been extensively studied in many mammalian genomes and, although it is commonly found at the promoter regions of genes, it is also involved in a number of different biological functions. In other complex animals, such as social insects, DNA methylation has been determined to be involved in caste differentiation and to occur primarily in gene bodies. The role of methylation in nonsocial insects, however, has not yet been explored thoroughly. Here, we present the whole-genome DNA methylation profile of the nonsocial hymenopteran, the jewel wasp ( Nasonia vitripennis ). From high-throughput sequencing of bisulfite-converted gDNA extracted from male Nasonia thoraces, we were able to determine which cytosine residues are methylated in the entire genome. We found that an overwhelming majority of methylated sites (99.7%) occur at cytosines followed by a guanine in the 3' direction (CpG sites). Additionally, we found that a majority of methylation in Nasonia occurs within exonic regions of the genome (more than 62%). Overall, methylation is sparse in Nasonia , occurring only at 0.18% of all sites and at 0.63% of CpGs. Our analysis of the Nasonia methylome revealed that in contrast to the methylation profile typically seen in mammals, methylation is sparse and is constrained primarily to exons. This methylation profile is more similar to that of the social hymenopteran species, the honey bee ( Apis mellifera ). In presenting the Nasonia methylome, we hope to promote future investigation of the regulatory function of DNA methylation in both social and nonsocial hymenoptera.
    Electronic ISSN: 2160-1836
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2018-10-04
    Description: The haplodiploid system of sex determination of Hymenoptera acts as an exaptation for species to evolve novel forms of asexual reproduction including thelytoky (clonal offspring of the mother). During normal reproduction in Hymenoptera, three of the four products of meiosis that are present in newly-laid eggs are lost as polar bodies, while the remaining pronucleus either develops as a haploid male or fuses with a sperm nucleus to produce a diploid zygote. In contrast, in thelytokous reproduction, which is uncommon but taxonomically widespread, two of the four products of meiosis fuse, as if one acted as a sperm. Queenless workers of Apis mellifera capensis , a subspecies of honey bee from South Africa, routinely reproduce thelytokously. Unmated A. m. capensis queens can also be induced to lay thelytokously by narcosis with carbon dioxide, but mated queens are never thelytokous. We artificially inseminated A. m. capensis queens using CO 2 narcosis. Up to 1/3 of offspring workers carried two maternal alleles and an allele of one father whereas no three-allele progeny were seen in control queens of the arrhenotokous (unfertilized eggs result in males) subspecies A. m. scutellata . Flow cytometry of three-allele individuals revealed that they were triploid and arose from the fertilization of a thelytokous fusion nucleus. We then reared six queens from a narcotized A. m. capensis queen and determined the ploidy of the offspring queens based on microsatellites. One of the five daughters was triploid. Following artificial insemination, this queen produced unfertilized thelytokous diploid eggs at high frequency, and unfertilized triploid eggs at much lower frequency. If fertilized, thelytokous diploid eggs were non-viable, even though triploidy in itself does not impede normal development. In contrast, when the rarer triploid eggs were fertilized, a proportion developed into viable tetraploids. Our study highlights the extraordinary developmental flexibility of haplo-diploid systems.
    Electronic ISSN: 2160-1836
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2014-05-09
    Description: Eusocial insects undoubtedly evolved from solitary ancestors, but how this occurred is not well established. The Ground Plan hypothesis suggests that gene networks that once regulated the oviposition and foraging phases of an ancestral solitary insect’s life cycle have been co-opted to establish the queen–worker dimorphism in extant eusocial insects; queens permanently express genes that were once expressed during the oviposition phase, whereas workers express genes that were once associated with foraging. An extension of the Ground Plan hypothesis, the Reproductive Ground Plan-forager hypothesis, proposes that foraging specialization by worker honey bees for either pollen or nectar is controlled by the same reproductive gene networks. According to the Reproductive Ground Plan-forager hypothesis, workers with more ovarioles forage early in life and specialize in pollen collection. Here we find that among workers of a highly reproductive honey bee subspecies, Apis mellifera capensis , there is a positive correlation between ovariole number and age at onset of foraging, and no association between ovariole number and foraging preference, thus contradicting key aspects of the Reproductive Ground Plan-forager hypothesis. We also find a negative association between ovariole number and ovary activation, suggesting that high ovariole number is not directly related to reproductive potential as previously assumed.
    Print ISSN: 1045-2249
    Electronic ISSN: 1465-7279
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2015-01-14
    Print ISSN: 0018-067X
    Electronic ISSN: 1365-2540
    Topics: Biology
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2007-09-12
    Print ISSN: 0018-067X
    Electronic ISSN: 1365-2540
    Topics: Biology
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2014-07-23
    Print ISSN: 0018-067X
    Electronic ISSN: 1365-2540
    Topics: Biology
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2015-12-30
    Description: Worker sterility is a defining characteristic of eusociality. The existence of the sterile worker caste remains a fundamental question for evolutionary biology as it requires the existence of genes that reduce personal reproduction. Currently, little is known about the proximate mechanisms underpinning worker sterility. Studies into a mutant "anarchistic" strain (in which workers can activate their ovaries) of honey bee, Apis mellifera , identified a list of candidate genes that regulate ovary activation. We quantified the expression of the four most promising candidate genes ( Anarchy , Pdk1 , S6k , and Ulk3 ) in nonactivated and activated ovaries of wild-type workers. Ovarian expression of Anarchy , a peroxisomal membrane protein, predicts the ovary state of workers with 88.2% accuracy. Increased expression of Anarchy in the ovary is strongly associated with suppression of oogenesis and its expression is sensitive to the presence of the queen. Therefore, Anarchy satisfies key criteria for a "gene underlying altruism". When we knocked down expression of Anarchy in the ovary using RNA interference (RNAi) we altered the expression of Buffy , a gene that regulates programmed cell death. Whole-mount multiplex fluorescent in situ hybridization (mFISH) shows Anarchy transcripts localize to degenerating oocytes within the ovary. Our results suggest that Anarchy is involved in the regulation of oogenesis through programmed cell death. The evolution of facultative worker sterility most likely occurred when the conserved mechanism of programmed cell death was co-opted to regulate ovary activation. Anarchy may therefore be the first example of a gene that has evolved through kin selection to regulate worker sterility.
    Print ISSN: 0737-4038
    Electronic ISSN: 1537-1719
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2017-08-23
    Print ISSN: 0018-067X
    Electronic ISSN: 1365-2540
    Topics: Biology
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...