Too hard to swallow: A secret secondary defence of an aposematic insect

Lu Yi Wang, Wen San Huang, Hsin Chieh Tang, Lung Chun Huang, Chung Ping Lin*


研究成果: 雜誌貢獻期刊論文同行評審

24 引文 斯高帕斯(Scopus)


Anti-predator strategies are significant components of adaptation in prey species. Aposematic prey are expected to possess effective defences that have evolved simultaneously with their warning colours. This study tested the hypothesis of the defensive function and ecological significance of the hard body in aposematic Pachyrhynchus weevils pioneered by Alfred Russel Wallace nearly 150 years ago. We used predation trials with Japalura tree lizards to assess the survivorship of 'hard' (mature) versus 'soft' (teneral) and 'clawed' (intact) versus 'clawless' (surgically removed) weevils. The ecological significance of the weevil's hard body was evaluated by assessing the hardness of the weevils, the local prey insects, and the bite forces of the lizard populations. The existence of toxins or deterrents in the weevil was examined by gas chromatography-mass spectrometry (GC-MS). All 'hard' weevils were instantly spat out after being bitten once and survived attacks by the lizards. In contrast, the 'soft' weevils were chewed and subsequently swallowed. The results were the same regardless of the presence or absence of the weevil's tarsal claws. The hardness of 'hard' Pachyrhynchus weevils was significantly higher than the average hardness of other prey insects in the same habitat and the mean bite forces of the local lizards. The four candidate compounds of the weevil identified by GC-MS had no known toxic or repellent functions against vertebrates. These results reveal that the hardness of aposematic prey functions as an effective secondary defence, and they provide a framework for understanding the spatio-temporal interactions between vertebrate predators and aposematic insect prey.

期刊Journal of Experimental Biology
出版狀態已發佈 - 2018 1月

ASJC Scopus subject areas

  • 生態學、進化論、行為學與系統學
  • 生理學
  • 海洋科學
  • 動物科學與動物學
  • 分子生物學
  • 昆蟲科學


深入研究「Too hard to swallow: A secret secondary defence of an aposematic insect」主題。共同形成了獨特的指紋。