Speciation & Set Trippin'

Scientists have announced a breakthrough, as a Butterfly unlocks evolution secret.

Given our planet's rich biodiversity, "speciation" clearly happens regularly, but scientists cannot quite pinpoint the driving forces behind it.

Now, researchers studying a family of butterflies think they have witnessed a subtle process, which could be forcing a wedge between newly formed species.

The team, from Harvard University, US, discovered that closely related species living in the same geographical space displayed unusually distinct wing markings.

These wing colours apparently evolved as a sort of "team strip", allowing butterflies to easily identify the species of a potential mate.

This process, called "reinforcement", prevents closely related species from interbreeding thus driving them further apart genetically and promoting speciation.

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The Harvard team made the discovery while studying the butterfly genus Agrodiaetus, which has a wide ranging habitat in Asia.

The females are brown while the males exhibit a variety of wing colours ranging from silver and blue to brown.

Dr Kandul and his colleagues found that if closely related species of Agrodiaetus are geographically separate, they tend to look quite similar. That is to say, they do not display a distinctive "team strip".

But if similarly closely related species are living side-by-side, the researchers noticed, they frequently look strikingly different - their "teams" are clearly advertised.

This has the effect of discouraging inter-species mating, thus encouraging genetic isolation and species divergence.

"This butterfly study presents evidence that the differences in the male's wing colouration is stronger [when the species share a habitat] than [when they do not]," said the speciation expert Axel Meyer, from Konstanz University in Germany.

"This pattern would therefore support the interpretation that it was brought about by reinforcement, hence natural selection."

There is still no word yet, on how much speciation is responsible for Crips and Bloods, Norteños and Sureños, or even power ties, toupees, and Camaros.