As a mound building species, digging is an intrinsic behavior of the red imported fire ants, Solenopsis invicta Buren. In this study, digging behavior of S. invicta was studied using sand as a digging substrate. When the group is small, grouped ants often had a significantly higher digging amount per individual than an ant in solitary, indicating that social facilitation occurred among ants. However, with ant numbers increased further, the digging amount per ant decreased, indicating digging inhibition took place. Ants preferentially dug the sand treated with worker body extracts and more ants were found in the treatment at the end of experiment. The body extract significantly increased the percentage of ants that exhibited digging behavior. These results indicate that chemical cues may play a role in social facilitation of digging behavior in red imported fire ants; however, these data can't explain the social inhibition observed in this experiment. The mechanisms behind the social facilitation, social inhibition and their transition require further investigation. This article is protected by copyright. All rights reserved.

中文翻译：

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红火蚁 Solenopsis invicta 挖掘行为的社会促进和抑制证据

红火蚁Solenopsis invicta Buren作为一种筑丘种，挖土是红火蚁的固有行为。在这项研究中，使用沙子作为挖掘基材研究了 S. invicta 的挖掘行为。当群体较小时，成群的蚂蚁每只蚂蚁的挖掘量往往显着高于单独的蚂蚁，表明蚂蚁之间发生了社会促进。然而，随着蚂蚁数量的进一步增加，每只蚂蚁的挖掘量减少，表明发生了挖掘抑制。蚂蚁优先挖用工人尸体提取物处理的沙子，并且在实验结束时发现更多的蚂蚁在处理中。身体提取物显着增加了表现出挖掘行为的蚂蚁的百分比。这些结果表明，化学线索可能在红火蚁挖掘行为的社会促进中发挥作用；然而，这些数据并不能解释在这个实验中观察到的社会抑制。社会促进、社会抑制及其转变背后的机制需要进一步研究。本文受版权保护。版权所有。