fishes spawning during evening crepuscular periods have not been overtly deterred 

 by the potential threat of predation. Alternatively, the adaptive pressures 

 favoring zygote survival may have been more influential in molding the diel 

 timing of reproduction than factors affecting survival of the parents (e.g., 

 predation) while spawning during the evening crepuscular period. 



ACKNOWLEDGMENTS 



We are grateful for the stimulating conversation and help received from 

 our fellow aquanaut, William Hamilton III, both underwater and topside. The 

 study was made possible by the tireless support of the HYDROLAB personnel, Bill 

 and Joan Schane, Barry Walden, Rod Catanach, and Joe Langersdorf, and support 

 divers, Scott Grace and Don Morris. Valerie Paul, Stacy Tighe, and Nancy Wolf 

 greatly aided in the field observations. We also received generous support 

 from the West Indies Laboratory, for which we are grateful. We thank Marjorie 

 Reaka and William McFarland for their thoughtful reviews of this paper. This 

 research was funded by a NOAA HYDROLAB (NULS 80-1) grant to S. Neudecker and by 

 an OPER grant from the Institute of Ecology, University of California at Davis, 

 to William Hamilton, S. Neudecker, and P. Ward. 



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