Graduate School of Agriculture, Kagawa University, Kagawa, Japan.
Faculty of Agriculture, Okayama University, Okayama, Japan.
Biol Lett. 2020 Dec;16(12):20200601. doi: 10.1098/rsbl.2020.0601. Epub 2020 Dec 23.
Tonic immobility and escape are adaptive anti-predator tactics used by many animals. Escape requires movement, whereas tonic immobility does not. If anti-predator tactics relate to weapon size, males with larger weapons may adopt tonic immobility, whereas males with smaller weapons may adopt escape. However, no study has investigated the relationship between weapon size and anti-predator tactics. In this study, we investigated the relationship between male weapon size and tonic immobility in the beetle . The results showed that tonic immobility was more frequent in males with larger weapons. Although most studies of tonic immobility in beetles have focused on the duration, rather than the frequency, tonic immobility duration was not affected by weapon size in . . Therefore, this study is the first, to our knowledge, to suggest that the male weapon trait affects anti-predator tactics.
强直静止和逃避是许多动物用来适应防御捕食者的策略。逃避需要运动，而强直静止则不需要。如果防御策略与武器大小有关，那么具有较大武器的雄性可能会采用强直静止，而具有较小武器的雄性可能会采用逃避。然而，目前还没有研究调查武器大小与防御策略之间的关系。在这项研究中，我们调查了雄性武器大小与甲虫强直静止之间的关系。结果表明，具有较大武器的雄性出现强直静止的频率更高。虽然大多数关于甲虫强直静止的研究都集中在持续时间上，而不是频率上，但在 中，强直静止的持续时间并没有受到武器大小的影响。因此，这项研究是我们所知的第一个表明雄性武器特征影响防御策略的研究。
