Large libellulid dragonflies often fly higher than smaller libellulids. We hypothesized that this size-related pattern in flight height might be caused by aggressive displacement. We tested this hypothesis by using a 30 m “dragonfly zip-line” to reel dead dragonfly decoys of four species of different sizes (Erythemis simplicicollis, Libellula incesta, Pachydiplax longipennis, and Perithemis tenera) along…
Interpretations of behavioural visual cues, based on human perception of colour, may mislead because of the difference in our visual range compared to other animals. Investigations into ultraviolet (UV) reflectance have shown that this can be an important mode of communication in many animals. The present study focused on 10 species of British Odonata. Digital