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141.
Efficient cooperation in eusocial insect colonies requires effective communication, and there is abundant evidence of non-volatile
chemicals playing a role in regulating reproduction within colonies. In contrast, there have been fewer studies investigating
the role of volatile chemicals. This study investigated the potential role of volatile chemicals in regulating queen reproduction
either by directly inhibiting queen reproduction or by honestly signalling queen fecundity to workers. We tested this using
multiple queen colonies of the ant (Leptothorax acervorum) from a functionally monogynous population where one queen monopolizes all reproduction. Nine colonies, each with an established
laying queen, were split to produce two colony fragments—one containing the reproducing queen (group 1) and one containing
only previously non-reproducing queens (group 2). Each group was separated by a fine wire mesh preventing physical contact,
but allowing volatile chemical contact. In each group 2 fragment, we found that a single formerly non-reproductive queen commenced
reproduction and that the rate of egg laying and maximum number of eggs recorded did not significantly differ between groups
1 and 2, results that do not support volatile chemicals as playing a role in regulating queen reproduction. Instead, our findings
suggest that physical contact is necessary to maintain functional monogyny. 相似文献
142.
Smith MJ Flowers TH Cowling MJ Duncan HJ 《Journal of environmental monitoring : JEM》2003,5(2):359-362
The use of underwater optical sensors to monitor pollution and climate change processes has led to the development of robust instruments able to be deployed in lakes and seas for months at a time. However, despite this improvement in their durability they are subject to biofouling on their optical ports resulting in erroneous readings. The use of hydrogel coatings containing the cationic surfactant benzalkonium chloride (BAC) has been shown to prevent the development of biofouling for up to 12 weeks in the marine environment. In this study the use of hydrogel coatings in the freshwater environment was less successful with fouling visible at 2 weeks. In both field and laboratory studies a rapid initial loss of BAC from the hydrogel film was observed. The loss is a combination of diffusive and mass flow but the period from 12 to 50 h appeared to fit to diffusion kinetics and a diffusion coefficient of 7.3 x 10(-8) cm2 s(-1) (13 degrees C) was calculated, an order of 10 times greater than that found in seawater. Subsequently the rate of loss of the residual BAC, for which a diffusion coefficient of 5.7 x 10(-10) cm2 s(-1) (15 degrees C) was measured, was too low to prevent the early stages of biofouling. 相似文献
143.
Mark K. Greco Dorothee Hoffmann Anne Dollin Michael Duncan Robert Spooner-Hart Peter Neumann 《Die Naturwissenschaften》2010,97(3):319-323
Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species
are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social
bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic
radioentomology, that stingless bee workers (Trigona carbonaria) immediately mummify invading adult small hive beetles (Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast
to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification
in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and
their parasites. 相似文献