نتایج جستجو برای: apis mellifera
تعداد نتایج: 10249 فیلتر نتایج به سال:
There is growing concern about declines in pollinator species, and more recently reservations have been expressed about mismatch in plant-pollinator synchrony as a consequence of phenological change caused by rising temperatures. Long-term changes in honeybee Apis mellifera phenology may have major consequences for agriculture, especially the pollinator market, as well as for honey production. ...
Most models of animal choice behaviour assume that desirable but unavailable options, such as a high quality, but inhabited nest sites, do not influence an individual's preferences for the remaining options. However, experiments suggest that in mammals, the mere presence of such 'phantom' alternatives can alter, and even reverse, an individual's preferences for other items in a choice set. Phan...
Biological patterns are often constructed via a combination of mechanisms including self-organization, templates and recipes. Our understanding of self-organization is becoming increasingly clear, yet how multiple mechanisms work together and what selective advantage they confer over simpler mechanisms is poorly understood. Honeybee (Apis mellifera) combs exhibit a pattern of brood at the botto...
Foraging by honeybee workers was investigated from the moment of the first foraging flight until death. To minimise the influence of factors other than senescence the foragers were trained to collect food from an artificial flower close to their hive. During each foraging trip the workers repeatedly visited an artificial flower, collecting one microlitre of 50% sugar solution per visit. During ...
Nine different genetic families of honey bees (Apis mellifera L.) were compared using summed z-scores (phenotypic values) and a modified selection index (Imod). Imod values incorporated both the phenotypic scores of the different traits and the economic weightings of these traits, as determined by a survey of commercial Ontario beekeepers. Largely because of the high weight all beekeepers place...
Social insects use both environmental and heritable (genetic) recognition cues when discriminating between nestmates and non-nestmates. In honeybees, Apis mellifera, both types of recognition cues are used, although their relative importance depends upon context, experimental design and environmental factors. Our aim in this study was to investigate which cues honeybees use to discriminate betw...
An aqueous extract of royal jelly from Apis mellifera produced hypoglycemia when injected into larvae of Manduca sexta. Application of specific radioimmunoassay to the partially-purified extract showed that royal jelly contains several insulin-like peptides, the major immunoreactive component of which has an apparent mol. wt similar to that of bovine insulin. These results suggest the existence...
Until recently, only three species of Varroa mites had been recorded: Varroa jacobsoni, V. underwoodi and V. rindereri. Of these, V. jacobsoni had received the most attention from researchers, primarily because it was believed to have switched host from the Asian bee (Apis cerana) to the European honey bee (A. mellifera) some 40-50 years ago, then spread to become a serious parasite of A. melli...
Predator-prey relationships between sympatric species allow the evolution of defense behaviors, such as honeybee colonies defending their nests against predatory wasps. We investigated the predator-prey relationship between the honeybee (Apis mellifera ligustica) and the European wasp (Vespula germanica) by evaluating the effectiveness of attack and defense behaviors, which have coevolved in th...
Axis formation is a key step in development, but studies indicate that genes involved in insect axis formation are relatively fast evolving. Orthodenticle genes have conserved roles, often with hunchback, in maternal anterior patterning in several insect species. We show that two orthodenticle genes, otd1 and otd2, and hunchback act as maternal anterior patterning genes in the honeybee (Apis me...
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