Synchronising anti-predator behaviour in the red flour beetle Tribolium castaneum

In many animals, a phenomenon is often observed in which behaviour depends on population density and many individuals within the group synchronise their state of behaviour to some extent, and theoretical studies have suggested that this synchronisation phenomenon is adaptive for predation avoidance. Moreover, death-feigning behaviour (DF) has been observed as an anti-predator strategy in many animals. There are large individual differences in the duration of DF, and the optimal duration of DF often varies depending on the situation. Therefore, although it is expected that prey may synchronise with others around them for an optimal DF duration, there are few experimental studies testing this hypothesis. This study investigated whether DF duration varies with and without other individuals, and whether it synchronised with the DF duration of other individuals, in the red flour beetle Tribolium castaneum. This study used populations with genetically longer (L-population) and shorter (S-popu..., Insect and culture
A stock culture of T. castaneum, in laboratories for more than 30 years, was used in this study. The beetles were reared on a mixture of wholemeal enriched with yeast in an incubator maintained at 25℃ under a 16:8 h (light: dark) photoperiod (lights on at 7:00; lights off at 23:00). Distinct morphological characters of the abdomen were used in sex determination of beetles at the pupal stage. Then, single-sex groups were stored in a dish (diameter 90 mm, height 15 mm) until experiments were performed. The focal individuals in each treatment were randomly collected from this stock culture.
Selected populations for the duration of death feigning
L-population with long DF duration and S-population with short DF duration in T. castaneum were established by a previous study (Miyatake et al., 2004), and these selection regimes have been maintained for over 30 generations (Matsumura and Miyatake, 2018). More details of this selection were described in previous studies (Matsum..., , # Synchronising anti-predator behaviour in the red flour beetle Tribolium castaneum

**Description of the data and file structure**

A *T. castaneum* stock culture, maintained for over 30 years, was used. Beetles were reared on yeast-enriched wholemeal at 25℃ under a 16:8 h light-dark photoperiod. Sex was determined at the pupal stage by abdominal morphology, and single-sex groups were stored until experiments.

L- and S-populations with long and short death feigning (DF) durations were established and maintained for over 30 generations (Miyatake et al., 2004; Matsumura and Miyatake, 2018). Despite 20 years, the populations still show large differences in DF duration.

In phase I, DF duration was measured in virgin beetles (21–35 days old) using a stick stimulus, recording immobility duration. On the next day, beetles were placed in plastic containers with food for three treatments: alone, cohabitation with L-population, and cohabitation with S-p

**File:** Synchronising_anti-predator_b...