College of Science and Engineering, James Cook University, P. O. Box 6811, Cairns, QLD 4870, Australia; Centre for Tropical Environmental and Sustainability Sciences, James Cook University, P.O. Box 6811, Cairns, QLD 4870, Australia.
College of Science and Engineering, James Cook University, P. O. Box 6811, Cairns, QLD 4870, Australia; Centre for Tropical Environmental and Sustainability Sciences, James Cook University, P.O. Box 6811, Cairns, QLD 4870, Australia.
Behav Processes. 2023 Apr;207:104857. doi: 10.1016/j.beproc.2023.104857. Epub 2023 Mar 11.
Many species show inter-individual variation in exploratory behaviours that are consistent over time, reflecting a personality. Differences in exploration can affect how individuals acquire resources and use their environment. However, few studies have considered whether exploratory behaviours are consistent across developmental life stages, such as when individuals disperse out the natal territory or when they become sexually mature. We therefore investigated the consistency of exploration behaviours towards a novel object and novel environment in a native Australian rodent, the fawn-footed mosaic-tailed rat Melomys cervinipes across development. Individuals were tested in an open field test and novel object test for five trials across four different life stages (pre-weaning, recently weaned, independent juvenile, sexually mature adult). We found that individual mosaic-tailed rats were consistent in their exploration of novel objects over these life stages, as these behaviours were repeatable and did not change across testing replicates. However, how individuals explored novel environments was not repeatable and changed across development, with exploration peaking during the independent juvenile stage. These results suggest that the way an individual interacts with novel objects may be somewhat constrained by genetic or epigenetic effects early in development, whereas spatial exploration could be more flexible to facilitate developmental shifts, such as dispersal. The life stage of an animal should therefore be taken into consideration when assessing personality in different species.
许多物种表现出个体间的探索行为差异，这些差异在时间上具有一致性，反映了个体的性格。探索行为的差异会影响个体获取资源和利用环境的方式。然而，很少有研究考虑探索行为是否在发育的不同阶段保持一致，例如个体从出生地扩散出去或性成熟时。因此，我们研究了澳大利亚本土啮齿动物——赤足鼠在发育过程中对新物体和新环境探索行为的一致性。个体在四个不同的生命阶段（断奶前、最近断奶、独立幼鼠、性成熟成年）的五个试验中进行了开阔地测试和新物体测试。我们发现，个体赤足鼠在这些生命阶段对新物体的探索具有一致性，因为这些行为是可重复的，并且在测试重复中没有变化。然而，个体如何探索新环境是不可重复的，并且随着发育而变化，探索在独立幼鼠阶段达到顶峰。这些结果表明，个体与新物体相互作用的方式可能在发育早期受到遗传或表观遗传效应的一定限制，而空间探索可能更加灵活，以促进如扩散等发育转变。因此，在评估不同物种的个性时，应该考虑动物的生命阶段。
