In a study published in the journal Nature, lead author Rosser of the National Geographic Explorer team revealed how hybridization can lead to the evolution of new species. The research found that two parental species of H. elevatus had remained distinct for around two million years until a DNA mishap occurred approximately 180,000 years ago during a global ice age when the Amazonian rainforest served as a biodiversity refugium.
This discovery is significant as it confirms what many scientists have long sought to find – an animal species that originated from two parental species combining their genomes. Mules are an example of a hybrid. This finding would have been missed by Charles Darwin if he had not explored further inland when the HMS Beagle docked in Lima in 1835, as these species were also found in the rainforests of South America.
David Lohman, a professor at City College of New York who was not involved in the study, praised the findings and stated that the researchers had demonstrated a phenomenon in nature that many had hypothesized but few had proven. Lohman is part of a team that recently constructed the most comprehensive butterfly tree of life.
Heliconius butterflies are unique as they consume flower pollen and use it to produce cyanogenic glycosides which make them distasteful to predators. They display bright high-contrast aposematic coloration which signals their unpalatability to potential threats.