- Checkerspots (Melitaeini, Nymphalidae, Lepidoptera) are usually considered a textbook example of aposematic butterflies and several studies on Nearctic species confirm this.
- The responses of the avian predator, the great tit (Parus major L., Paridae, Passeriformes), to five species of Palaearctic checkerspots and one control palatable ringlet (Aphantopus hyperanthus L., Satyrinae, Nymphalidae, Lepidoptera) were observed.
- None of the tested checkerspots was attacked more often than the control palatable ringlet, which suggests that birds originating from the wild had no previous bad experiences with them. Nonetheless, certain tested butterfly species (Melitea didyma, Esper; Melitea aurelia, Nickerl, and probably Melitea athalia, Rottemburg; Melitaeini, Nymphalidae, Lepidoptera) elicited some aversion in great tits (a long time handling them, a small portion of the body eaten, and some discomfort after ingestion).
- Larvae of commonly eaten species (Melitea diamina, Lang; Euphydryas aurinia, Rottemburg; Melitaeini, Nymphalidae, Lepidoptera) feed on plants containing secoiridoids (in contrast to the earlier mentioned protected species, which feed mostly on plants containing iridoid glycosides); therefore the efficiency of secoiridoids in the chemical protection of butterflies is discussed.