Scientists said on Wednesday they have created a distinctive red and yellow butterfly in the laboratory by interbreeding two different species in a way similar to what they believe has occurred in nature.
The laboratory hybrid is nearly identical to a wild species of butterfly in Colombia known as Heliconius heurippa.
"We recreated the evolutionary steps that may have given rise to Heliconius heurippa, a hybrid butterfly species, in the lab," said Jesus Mavarez, of the Smithsonian Tropical Research Institute in Panama City, Panama.
Animal hybrids are thought to be very rare because they are less able to survive. The mule for example, a hybrid between a donkey and a horse, is sterile so it is an evolutionary dead end. But some hybrids survive and establish new species.
The achievement by Mavarez and researchers in Colombia and Britain, which is reported in the journal Nature, suggests animal hybrids could be more common than previously thought.
The scientists began their experiments after noticing that Heliconius heurippa's distinct wing pattern was similar to two other species of butterfly.
After interbreeding the two types, they found the laboratory hybrid was very similar to the wild species.
The scientists said the colour pattern on the wing of Heliconius heurippa, which is a mating cue, makes it unattractive to members of their parents' species but attractive to each other.
Scientists suggest that similar rapid species creation could help to explain puzzling groups of closely related species such as Darwin's finches and cichlid fish. The finding is yet another challenge to the charge from creationists that evolutionary biologists are unable to explain large scale evolutionary shifts that result in new species.
The old biological dogma is that speciation, the process by which a new species forms, happens when two populations of the same species become separated for millennia by a new mountain range or a change in a river's course, for example.
In their separate environments, the two diverge genetically and cannot mate when they come back together again. "The orthodoxy up to now is that it mostly has a destructive role," said George Turner, a professor of evolutionary biology at the University of Hull, England.
"That's how species sometimes come to an end when they collapse into each other and all their unique adaptations are all mashed up together."
But Chris Jiggins at the University of Edinburgh, Scotland, and his colleagues were able to recreate butterflies with the same characteristics as Heliconius heurippa after just three generations of breeding in the lab between two related parent species H. melpomene and H. cydno.
Source: China Daily