228 
Psyche 
[Vol. 93 
difficult to explain. Condensation for overwintering might serve 
important social functions. Alternatively, a tantalizing suggestion 
based on laboratory data is that nest survivorship in winter is a 
function of resident queen number (Herbers 1986b). If the same 
relation holds in nature, then nests subunits may have higher survi- 
vorship in concert than they would alone. Whatever the proximate 
and ultimate causes, the seasonal cycle in polydomy deserves closer 
scrutiny. 
Acknowledgments 
This study was supported by grants from the National Academy 
of Sciences and the National Science Foundation (DEB 82-02361 
and BSR-85 16639). 
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