for National Geographic News
A butterfly species from South America has been revealed as nature's answer to Frankenstein's monster, scientists say.
New research shows the insect was originally created from two different butterflies in an evolutionary process many biologists didn't think possible.
The scientists arrived at this conclusion by successfully re-creating the butterfly in the lab, using "second-hand parts" from two related species.
Animals are thought usually to evolve in the opposite manner, when a single species gradually splits into two over many generations.
The team behind the discovery describes how it re-created the black, red, and yellow Heliconius heurippa butterfly in tomorrow's issue of the journal Nature.
Researchers say their creation reveals a process called hybrid speciation, in which the genes of two existing species combine to produce a third.
The study suggests hybridization may be more important to the evolution of new animals than had previously been thought.
Hybrids such as the mule, a cross between a donkey and a horse, are sterile. But the team says the butterfly hybrid brought together a combination of genes that allowed it to breed and there be considered a new species.
Evolution and Sex
Found in the high-altitude cloud forests of Venezuela and Colombia, H. heurippa was believed to be a hybrid because its wing patterns look like a mixture of two other Heliconius butterflies, scientists say.
(Learn about Colombian cloud-forest ecosystems.)
The insect has yellow markings from one species and red from the other, they explain.
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