Example of Müllerian mimicry: toxic (as sequestering cardiac glycosides) monarch (Danaus plexippus) and toxic as well (as sequestering the salicylic acid) viceroy (Limenitis archippus, also shown in this collection) evolved resemblance in colour and pattern on wings, jointly making stronger warning to predators that avoid them as inedible.
Danaus plexippus Monarch
Male. Dorsal view.
Canada, Ontario, Upper Stony Lake.