Comparison of flight behaviors among laboratory and field strains in Tribolium castaneum (Coleoptera: Tenebrionidae) using a simple method to measure flight ability

Abstract Most insects can fly. The acquisition of flight is a factor that allows insects to prosper on Earth. On the other hand, in the same species and population, individual differences in flight ability may occur. Flight ability can vary due to geographical conditions and cumulative rearing. Investigating these changes in flight performance is important for understanding dispersal polymorphism and the evolution of flight performance. Thus, in the present study, the flight behaviors between cumulative rearing and field strains and changes in flight behaviors between strains of the red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae), which is distributed around the world were compared . Tribolium castaneum is a worldwide pest of stored grains. Its body length is about 3–4 mm. Previous studies have investigated the influence of environmental and physiological factors on the flight of this species, but no studies have examined individual differences or polymorphism in flight behaviors within this species. In this study, we developed a simple apparatus that can quantify the flight behavior of this species. The experimental apparatus was set up as a double structure with two different size containers. This apparatus was able to assess the flight activity of insects by counting individuals in a big container because insects transfer to the big container only by flight. Moreover, upward flight ability was possible to be assessed by the apparatus adding the barrier. Then, the flight behavior was compared between strains of this species that have been bred in the laboratory for more than 45 years and several strains of this species collected in the field. The results showed no variation in flight activity between strains, but flying ability was higher in strains originating from warmer regions. Here, we discussed the variations in flight behavior of T. castaneum .