Prairie Dog Food Preference and the Photosynthetic Pathway-Selective Herbivory Hypothesis

Abstract

Black-tail prairie dogs (Cynomys ludovicianus) at the Tulsa Zoological <br /><br />Park were offered diets consisting of C3 and C4 plant species under conditions of <br /><br />controlled food species abundance and availability, in order to test whether the <br /><br />photosynthetic pathway-selective herbivory hypothesis is predictive of foraging <br /><br />behavior. The C4 species tested were Setaria italica, Zea mays, Eragrostis curvula, <br /><br />and Salsola kali. The C3 species tested were Arachis hypogea, Daucus carota, <br /><br />Helianthus annus, and Lactuca sativa. Four experiments were performed. I. Each <br /><br />food was presented separately to test whether C. ludovicianus would eat each <br /><br />species. II. All four C3 species were presented simultaneously to test for preferences <br /><br />within the C3 plant food group. III. All four C4 species were presented simulta- <br /><br />neously to test for preferences within the C4 food group. IV. Finally, all four C3 <br /><br />and all four C4 species were presented simultaneously to test for preferences <br /><br />between C3 and C4 food groups. Data demonstrated that prairie dogs have sig- <br /><br />nificant food preferences within both the C3 and C4 species groups tested. However, <br /><br />predictions of the photosynthetic pathway-selective herbivory hypothesis were <br /><br />not met. No statistical preference for either C3 or C4 species existed.