实验检验东方田鼠学习能力的性别差异

东方田鼠选择从禾本科植物叶片的不同部位采食会引起食物摄入率的巨大差异,这项具有明显的认知和学习行为的觅食活动是否存在性别差异。在由带两片叶的新鲜马唐茎秆配置的密集食物斑块上,测定东方田鼠觅食马唐叶片的行为序列、过程及参数,检验其在学习能力上的性别差异。结果表明,雌鼠和雄鼠的觅食决定时间尽管均随觅食学习天数的增加而减小,但雌鼠的觅食决定时间显著地高于雄鼠的;雌鼠和雄鼠均由从对叶片部位无差别选择和采食转向偏爱从叶片基部采食。学会这项采食技能后,雌鼠从叶片基部采食的选择指数显著地高于雄鼠的;二者的摄入率均随觅食学习天数的增加极显著地增大,但雌鼠的摄入率却极显著地高于雄鼠的。研究结果充分验证了提出的假设:雄鼠较雌鼠能更快地习得从禾本科植物叶片的基部采食和收获食物;但当二者习得这项采食技艺后,雌鼠较雄鼠能获得更高的食物摄入率;同时也说明,新建立的评价小型植食性哺乳动物认知和学习能力的实验方法,具有可靠的有效性和实用性。

Tests of sex differences in learning abilities of reed voles (Microtus fortis)

Sex differences in animals can have a significant impact on their cognitive processes as well as their behavior. In the case of reed voles (Microtus fortis), their feeding behavior, specifically the consumption of different parts of grass leaves, plays a crucial role in determining their food intake rates during foraging. However, the extent to which learning and cognitive processes vary between genders in this foraging behavior remains unclear. To bridge this knowledge gap, our study focused on investigating gender-specific learning and selection patterns of different leaf parts during the foraging process of reed voles, leveraging their inherent cognitive behavioral abilities. To ensure unbiased assessment of cognitive ability, we took measures to prevent prior exposure of the experimental individuals to objects resembling the stems and leaves of crabgrass (Digitaria sanguinalis) plants. In our experiments, we focused on concentrated food patches of crabgrass, each containing two fresh leaves per stalk. Meticulous measurements were conducted to capture the sequence, processes, and parameters of vole foraging behavior. Our findings revealed several noteworthy insights. Firstly, the decision time for foraging decreased as the experimental days progressed for both female and male voles. However, the females consistently exhibited significantly longer decision times compared to males on each experimental day. Over time, both female and male voles exhibited a transition from random feeding across the three parts of the leaves to a clear preference for feeding on the leaves at the base. Notably, once the foraging skill was acquired, females demonstrated a significantly higher selection index for feeding on the leaves at the base compared to males. Furthermore, as the experimental days advanced, both female and male voles increased their food intake rates. However, the intake rates of females were found to be significantly higher than those of males. These findings support the hypothesis put forth in our study, indicating the presence of a gender gap in the cognition and learning capability of reed voles. Additionally, our results highlight that males acquire the foraging skill of feeding on the base part faster during the experimental process. However, once both females and males acquired this foraging skill, females surpassed males in achieving higher intake rates. Overall, this paper sheds light on the underlying cognitive abilities of reed voles and contributes to our understanding of gender differences in cognition and learning among small herbivorous mammals. Moreover, it demonstrates the reliability, effectiveness, and practicality of the newly established experimental method for evaluating cognitive and learning abilities in this species.