Patch Utilization by Three Species of Chilean Rodents Differing in Body Size and Mode of Locomotion

摘要: Predation risk influences differentially the foraging decisions of rodent spe- cies with different morphologies (body size and locomotion type). Explanations for patterns have been derived largely from behavior heteromyid rodents, there is a lack information regarding other groups morphologies. Nevertheless, explanations are thought to be applicable groups. In order study generality hypotheses about effect morphology on ecology, I investigated Chilean sigmodontine rodents (Muridae) in laboratory, experimentally manipulating nocturnal illumination (a surrogate pre- dation risk) food distribution. Three coexisting species matorral were compared: two quadrupeds, one large body (Phyllotis darwini) another small (Abrothrix olivaceus), bipedal escape (Oligoryzomys longicaudatus). The did not differ patch utilization consumption response distributions. However, was an overall significant consumption. When higher, A. olivaceus P. darwini increased transportation refuge decreased total They also significantly number trips between refuge. showed most cautious behavior. 0. longicaudatus insensitive conditions illumination. It argued that quadrupedal seem confer higher sensitivity Bipedality may less vulnerability predation, show facultative central-place foraging, diminishing possible greater potential risk. Former behaviors under as general previously assumed. This emphasizes need consider particular features system investigation.