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Walter Klingmüller 《Die Naturwissenschaften》1981,68(3):120-127
Examples for genetic engineering are the transfer of nuclei between cells of higher animals and the introduction of heterologous DNA into bacteria by means of plasmids. The former approach will help to establish new ways in animal breeding, the latter provides bacterial cells that produce proteins of medical importance. The moral justification of related studies in man is still open, but the possible risks of gene technology can be coped with by adhering to proper safety regulations. 相似文献
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Paula C. Díaz Christoph Grüter Walter M. Farina 《Behavioral ecology and sociobiology》2007,61(10):1589-1597
Floral scents are important information cues used to organize foraging-related tasks in honeybees. The waggle dance, apart
from encoding spatial information about food sources, might facilitate the transfer of olfactory information by increasing
the dissipation of volatiles brought back by successful foragers. By assuming that food scents are more intensive on specific
body parts of returning foragers, i.e., the posterior legs of pollen foragers and mouthparts of nectar foragers, we quantified
the interactions between hive mates and foragers during dances advertising different types of food sources. For natural sources,
a higher proportion of hive mates contacted the hind legs of pollen dancers (where the pollen loads were located) with their
heads compared to non-pollen dancers. On the other hand, the proportion of head-to-head contacts was higher for non-pollen
foragers during the waggle runs. When the food scent was manipulated, dancers collecting scented sugar solution had a higher
proportion of head-to-head contacts and a lower proportion around their hind legs compared to dancers collecting unscented
solution. The presence of food odors did not affect in-hive behaviors of dancers, but it increased the number of trophallaxes
in-between waggle runs (i.e., during circle phases). These results suggest that the honeybee dance facilitates the olfactory
information transfer between incoming foragers and hive mates, and we propose that excitatory displays in other social insect
species serve the same purpose. While recent empirical and theoretical findings suggested that the colony level foraging benefits
of the spatial information encoded in the waggle dance vary seasonally and with habitats, the role of the dance as a compound
signal not only indicating the presence of a profitable resource but also amplifying the information transfer regarding floral
odors may be important under any ecological circumstances. 相似文献