Heliconius melpomene, the postman butterfly, common postman or simply postman, is a brightly colored butterfly found throughout Central and South America. It was first described by Carl Linnaeus in his 1758 10th edition of Systema Naturae. Its coloration coevolved with a sister species H. erato as a warning to predators of its inedibility; this is an example of Müllerian mimicry. H. melpomene was one of the first butterfly species observed to forage for pollen, a behavior that is common in other groups but rare in butterflies. Because of the recent rapid evolutionary radiation of the genus Heliconius and overlapping of its habitat with other related species, H. melpomene has been the subject of extensive study on speciation and hybridization. These hybrids tend to have low fitness as they look different from the original species and no longer exhibit Müllerian mimicry. Heliconius melpomene possesses ultraviolet vision which enhances its ability to distinguish subtle differences between markings on the wings of other butterflies. This allows the butterfly to avoid mating with other species that share the same geographic range. Description The postman butterfly is predominately black with either red or yellow stripes across the forewings. The postman butterfly has large long wings (35–39 mm). It is poisonous and the red patterns on its wings are an example of aposematism. They look similar to H. erato. Two features found on the underside help to distinguish H. erato from H. melpomene—H. erato has four red dots where the wing attaches to the thorax while H. melpomene has three and the yellowish-white stripe on the underside reaches the margin of the hindwing in H. erato but ends before reaching the margin in H. melpomene. There are many morphs of this butterfly throughout Central and South America. The geographical variation in patterns has been studied using linkage mapping and it has been found that the patterns are associated with a small number of genetic loci called genomic "hotspots". Hotspot loci for color patterning have been found homologous between co-mimics H. erato and H. melpomene, strengthening evidence for parallel evolution between the two species, across morph patterns. Geographic range and habitat Heliconius melpomene is found from Central America to South America, especially on the slopes of the Andes mountains. It most commonly inhabits open terrain and forest edges, although it can also be found near the edges of rivers and streams. It shares its range with other