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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.
Bryan N. Duncan Yasuko Yoshida Jennifer R. Olson Sanford Sillman Randall V. Martin Lok Lamsal Yongtao Hu Kenneth E. Pickering Christian Retscher Dale J. Allen James H. Crawford 《Atmospheric environment (Oxford, England : 1994)》2010,44(18):2213-2223
We investigated variations in the relative sensitivity of surface ozone formation in summer to precursor species concentrations of volatile organic compounds (VOCs) and nitrogen oxides (NOx) as inferred from the ratio of the tropospheric columns of formaldehyde to nitrogen dioxide (the “Ratio”) from the Aura Ozone Monitoring Instrument (OMI). Our modeling study suggests that ozone formation decreases with reductions in VOCs at Ratios <1 and NOx at Ratios >2; both NOx and VOC reductions may decrease ozone formation for Ratios between 1 and 2. Using this criteria, the OMI data indicate that ozone formation became: 1. more sensitive to NOx over most of the United States from 2005 to 2007 because of the substantial decrease in NOx emissions, primarily from stationary sources, and the concomitant decrease in the tropospheric column of NO2, and 2. more sensitive to NOx with increasing temperature, in part because emissions of highly reactive, biogenic isoprene increase with temperature, thus increasing the total VOC reactivity. In cities with relatively low isoprene emissions (e.g., Chicago), the data clearly indicate that ozone formation became more sensitive to NOx from 2005 to 2007. In cities with relatively high isoprene emissions (e.g., Atlanta), we found that the increase in the Ratio due to decreasing NOx emissions was not obvious as this signal was convolved with variations in the Ratio associated with the temperature dependence of isoprene emissions and, consequently, the formaldehyde concentration. 相似文献