SHORT COMMUNICATIONS 
interactions with conspecifics. This is not surprising 
as the idea that animals are automatons seeking 
maximal caloric intake is. undoubtedly, naive 
i Pierce and Ollason 1987 provide a critique of 
optimal foraging theory). Most researchers reeog- 
nize anuanced approach is necessary to appreciate 
the variety of selective pressures operating on 
foraging organisms (see Stephens et al. 2007). but 
predictions based on simple assumptions are. for 
better or worse, often the default. Our results 
demonstrate inter- and intra-sexual interactions can 
have a dramatic effect on observed resource use. 
ACKNOWLEDGMENTS 
We thank the students of the Davidson College 2010 
Vertebrate Field Zoology class (Bio 322) for help in 
conducting this experiment (Manelle Abalo, Farced 
Cheema, Emily Copeland. Daniel Councell. Evan F.skew. 
Marion Floyd, Shawna Foley. Alejandro Goiualez-Stcwarl, 
Lucy Medley, Lauren Ivey, Currv Jones. Danielle Jordan. 
Waller Kucera. Ross Lackey, Phil LaTourette. Chris Lima. 
Meagan Madden. Kevin Mangum, Maddy MeCrcery. 
Molly Mon-ill, Samantha Meyers. Tannhya Miranda, Shane 
Purvis. Megan Reilly. Ben RilTe, Jeffrey Roth. Dairy 
Spasova, Gabrielle Wallace. Abbey Webb. Zemis Wilson. 
Colin Wint, and Lynea Wticzak). The manuscript was 
improved by the comments of J. R. BeltholT, C, L, Braun. 
E. L. Cline, and K. A. Turvin. 
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