Hanne & Jens Eriksen / Buck's horn groundsel {Senecio glaucus} in bloom amongst rocks, Ras Al Khaimah, United Arab Emirates

Hanne & Jens Eriksen / Buck's horn groundsel {Senecio glaucus} in bloom, Ras Al Khaimah, UAE

Doug Wechsler / Male Tiger swallowtail {Papilio glaucus} feeding on Buddleia flowers, Pennsylvania, USA.

Doug Wechsler / Tiger swallowtail butterfly (Papilio glaucas) feeding. Philadelphia, USA

Doug Wechsler / Tiger swallowtail butterfly, Virginia USA

Gerry Ellis / Tiger Swallowtail (Papilio glaucus) butterfly perching on pink flowers, North America