Is death–feigning adaptive? Heritable variation in fitness difference of death–feigning behaviour

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 271; no. 1554; pp. 2293 - 2296
• Main Authors: Miyatake, T., Katayama, K., Takeda, Y., Nakashima, A., Sugita, A., Mizumoto, M.
• Format: Journal Article
• Language: English
• Published: England The Royal Society 07.11.2004
• Subjects: Adaptation, Biological - physiology; Animals; Anti-Predator Behaviour; Artificial Selection; Beetles; Behavior, Animal - physiology; Coleoptera; Death; Deception; Defence; Ecological competition; Female; Female animals; Genetic inheritance; Hasarius adansoni; Immobility; Insect behavior; Male; Natural selection; Observation; Predation; Predators; Predatory Behavior - physiology; Quantitative Genetics; Salticidae; Selection, Genetic; Spiders; Spiders - physiology; Tenebrionidae; Thanatosis; Tribolium - physiology; Tribolium castaneum
• ISSN: 0962-8452; 1471-2954
• DOI: 10.1098/rspb.2004.2858

The adaptation of death-feigning (thanatosis), a subject that has been overlooked in evolutionary biology, was inferred in a model prey-and-predator system. We studied phenotypic variation among individuals, fitness differences, and the inheritance of death-feigning behaviour in the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Two-way artificial selections for the duration of death-feigning, over 10 generations, showed a clear direct response in the trait and a correlated response in the frequency of death-feigning, thus indicating variation and inheritance of death-feigning behaviour. A comparison of the two selected strains with divergent frequencies of death-feigning showed a significant difference in the fitness for survival when a model predator, a female Adanson jumper spider, Hasarius adansoni Audouin (Araneomophae: Salticidae), was presented to the beetles. The frequency of predation was lower among beetles from strains selected for long-duration than among those for short-duration death-feigning. The results indicate the possibility of the evolution of death-feigning under natural selection.