In a groundbreaking study, National Geographic Explorer Rosser demonstrated how hybridization could lead to the evolution of new species. The research revealed that the two parental species of H. elevatus had remained distinct for around two million years, but a DNA mishmash occurred approximately 180,000 years ago during a global ice age when the Amazonian rainforest served as a biodiversity refugium.
Scientists have long sought to find an animal species that originated from two parental species combining their genomes, with mules being an example of a hybrid. The discovery of the hybrid species and its two parental species in the rainforests of South America is significant. If Charles Darwin had explored further inland when the HMS Beagle docked in Lima in 1835, he would have encountered these species as well.
David Lohman, a professor at the City College of New York, who was not involved in the study, praised the findings, stating 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 in that they consume flower pollen, which they use to produce cyanogenic glycosides that make them distasteful to predators. They display bright, high-contrast aposematic coloration that signals their unpalatability to potential threats. This study highlights the importance of understanding how genetic mixing can lead to new and unique species adaptations and survival strategies in different environments over time.