1980] 
Hook & Matthews — Biology of Oxebelus 
35 
from 3.7% to 14.5%; Senotainia sp. was the predominant parasite, 
but Metopia sp. was also recorded. Ants {Solenopsispergandei Forel 
and Conomyrma sp.) were nest predators, with 13.5% cell mortality 
due to Solenopsis recorded at one site. Records of male association 
with nesting females are summarized from the literature. The idea is 
developed that the effect of a male’s presence and activity in reducing 
mortality from cleptoparasitism supersedure has been an important 
factor in the evolution of male nest guarding and female’s toleration 
of interference due to repeated copulation attempts. 
Acknowledgements 
This work was supported by a grant awarded to R. W. Matthews 
by the Edward John Noble Foundation in conjunction with the 
American Museum of Natural History. Special thanks to J. T. 
Woods and staff for their support on the island: J. E. Gillaspy for the 
use of unpublished information; R. J. Gagne, L. Knutson, W. N. 
Mathis, G. C. Steyskal, F. C. Thompson, A. S. Menke and D. R. 
Smith of the I.I.I.P.I., USDA, for determination of prey specimens, 
cleptoparasitic flies, wasps and ants. R. M. Bohart of the University 
of California at Davis assisted in wasp determinations. J. W. Krispyn 
helped with the field work and preparation of the manuscript and D. 
J. Peckham and G. C. Eickwort critically reviewed the manuscript. 
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