Gender difference in unconditioned and conditioned predator fear responses in Smith's zokors (Eospalax smithii)

Risk taking is imperative for the survival and fitness of animals since they constantly face innumerable threats from various sources. Indeed, the ability of the individual to balance between the costs and benefits of various options and adopt a wise decision is critical for the well-being of the animal. In the current study, we investigated gender differences in risk taking and decision making in male and female Smith's zokors (Eospalax smithii), a subterranean rodent species, in the defensive withdrawal apparatus (DWA) under novel, predator and conditioned contexts. Under novel context, males showed more exploratory and less hiding behavior than females especially during the first half of the testing session. However, under predator and conditioned contexts, non-significant sexually dimorphic behavioral differences were observed. Nevertheless, analysis of the performance of each gender separately across the three contexts revealed that males showed strong aversion to the predator and conditioned contexts. By contrast, females did not significantly vary their behavioral responses when exposed to the predator and conditioned cues. Our results suggest that males are more inclined to indulge in riskier exploratory activities while females may be regarded as risk-aversive. The current findings highlighted the functional significance of the trade-off between risk and exploration in the natural environment such that male and female zokors differed in how they gather and process information during risky confrontations that ultimately elicit significant variations in their decision-making and coping strategies to dangerous events. (C) 2018 Published by Elsevier B.V.