Tucson Botanical Gardens (Butterfly Magic at the Gardens)
Canon Powershot sx100is
Heliconius heurippa (Hybrid Speciation)
A graceful little butterfly called Heliconius heurippa lives in a small region of Columbia, just east of the Andes. Many other Heliconius (or passion-vine) butterflies live in South and Central America. Of particular interest is H. melpomene. Its wide range includes that of H. heurippa. The two butterflies have the same hindwing color, and they also share an orange streak across the forewing.
Scientists were also struck by the similarity between H. heurippa and another species, H. cydno. These two species share the same white streak across the wing. It does not live alongside H. heurippa, though. Its range stops at the western side of the Andes.
H. heurippa almost looks like a simple combination of the other two species. A team of scientists who study the butterfly wondered if that indeed was the case. Perhaps, they speculated, a population of H. cydno became isolated on the eastern side of the Andes from the other butterflies of its species. The isolated butterflies mated with the H. melpomene around them. Instead of merging with the other species, the butterflies became distinctive hybrids with an appearance all their own. They were attracted to their own appearance, while the original two species continued to be attracted to theirs. The hybrids became a new species: H. heurippa