干旱区生态环境知识资源中心

Salivary water loss during seed busking was examined in two rodent species, deer mice (Peromyscus maniculatus) and Great Basin pocket mice (Perognathus parvus), feeding on four species of seeds (lodgepole pine [Pinus contorta], antelope bitterbrush [Purshia tridentata], Jeffrey pine [Pinus jeffreyi], and sunflower [Helianthus annuus]). Great Basin pocket mice a. desert-adapted species, lost little or no salivary water while hushing seed Deer mice, however, lost significant quantifies of salivary water to all four seed species. This apparently occurred as moist surfaces of the lips and tongue contacted the hygroscopic seed coats during seed manipulation and husking. Relatively small or hygroscopic seed such as those of lodgepole pine and antelope bitterbrush, impose a greater relative cost in salivary water loss to deer mice than do larger seeds. Heteromyid rodents appear to have specialized lips that isolate the moist surfaces of the mouth from seeds. Fur-lined cheek pouches and specialized dips may assist these rodents to persist in arid environments by solving the problem of salivary water loss to the seeds they handle and store.