Understanding why social relationships vary among conspecifics is central to studies of animal behaviour. For many species, patterns of space use provide important insights into social behaviour. To characterize the social organization of the highland tuco-tuco (Ctenomys opimus), we used visual observations and radiotelemetry to quantify spatial relationships among adults in a population at Laguna de los Pozuelos, Jujuy Province, Argentina. Specifically, we sought to confirm anecdotal reports that these subterranean rodents are social, meaning that adults share burrow systems and nest sites. Our data indicate that the animals live in spatially distinct groups, although the number of individuals per group varies markedly. Although these relationships were robust with regard to location (above vs. below ground) and type of data (visual vs. telemetry), some groups identified during the daytime fissioned during the night. We suggest that the population of C. opimus at Pozuelos is facultatively social, meaning that individuals display predictable, adaptive differences in social relationships with conspecifics. More generally, our findings add to the growing number of subterranean species of rodents recognized as social, thereby generating new opportunities for comparative studies of these animals aimed at assessing the causes and consequences of variation in social organization.

中文翻译：

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地下啮齿动物，高地土库－土库（Ctenomys opimus）的兼性社会

了解动物之间的社会关系为何不同对于动物行为的研究至关重要。对于许多物种而言，空间利用方式为人们的社会行为提供了重要的见识。刻画高地土库族的社会组织（Ctenomys opimus），我们使用视觉观察和无线电遥测技术来量化阿根廷胡胡伊省拉古纳·德·洛斯·波祖埃洛斯人口中成年人之间的空间关系。具体而言，我们试图确认传闻，即这些地下啮齿类动物是社会性的，这意味着成年鼠具有洞穴系统和巢穴。我们的数据表明，这些动物生活在空间上不同的群体中，尽管每组中的个体数量明显不同。尽管这些关系在位置（高于地面还是低于地面）和数据类型（视觉还是遥测）方面很稳健，但在白天发现的一些小组在晚上裂变了。我们建议C. opimus的人口在Pozuelos的学校是兼职性的，这意味着个人在具有种名的社会关系中表现出可预测的，适应性的差异。更广泛地说，我们的发现增加了被认为是社会性的地下啮齿动物的数量，从而为这些动物的比较研究提供了新的机会，旨在评估社会组织变化的原因和后果。