Astraptes fulgerator是一种中大型的蝴蝶，是一种栖居于南美至北阿根廷的常见蝴蝶，普遍发现于都市庭院和热带雨林中。人类对于这个种的认知始于1775年，它们之前被认为是同一种。
在2004年10月1日的Proceedings of the National Academy of Sciences中，Hebert等人报道说，他们和宾州大学的Daniel Janzen等人合作，Hebert等人分析了哥斯达黎加的480个弄蝶样本，但是藉由先进的DNA编码分析，发现这些种其实具有基因歧异性，分属10个不同的品种，而且和它们选择的食物息息相关。
由于多达六个种居住在同一块土地上，所以显示这些蝴蝶中有生殖隔离的特性。由于蝴蝶的外观上十分相近，之间的差别相当轻微，所以只归因于一般微小的歧异性，这项发现对于生物多样性的维持有更大的涵义。
这项研究结果引起了一个有趣的问题，有多少野生动物也和者种蝴蝶一样，外观相似，但却是有生殖隔离的不同品种？
我们也许会哀叹植物或动物在某个地方绝种，但却庆幸还好牠们仍存在于地球上的其它地方，但事实上，这些物种可能已经真正消失了，存在于他处的物种其实是不同的物种。
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DNA Barcoders Nab New Species
Biologists dream of hand-held DNA scanners that could tell an ecologist in the field whether or not an organism is a new species. That dream is a long way from fruition, but two new tests of a molecular technique called DNA barcoding suggest that it will become a powerful tool for cataloging the diversity of life.
Hidden diversity.
Barcoding allows biologists to identify new butterfly species that have remarkably similar adult forms.
With species going extinct faster than they can be identified by traditional methods, a group of taxonomists has been developing DNA barcoding to speed up their work. The method focuses on DNA in the energy-generating mitochondria inside cells. Unlike DNA in the nucleus of cells, mitochondrial DNA evolves quickly. Unique changes will accumulate after two populations stop interbreeding, allowing biologists to tell whether two closely related organisms should be considered separate species.
Backers of this approach, including the authors of the new studies, have teamed up to form the Consortium for the Barcoding of Life. To standardize their efforts, they've agreed to use the 648 DNA letters of a mitochondrial gene called COI as the barcode marker. Their ultimate goal is to catalog the COI sequence of every species on Earth. But before that can happen, biologists have to make sure the technique is reliable.
The new work suggests that it is. A team led by Mark Stoeckle, a molecular ecologist at Rockefeller University in New York City, barcoded 260 bird species known to reproduce in the United States. Their results, published in the 28 September issue of the Public Library of Science, Biology, show that differences in the sequence of the COI gene are about 18 times greater between species than within species. Beyond demonstrating that DNA barcoding can distinguish known bird species, they found that four unknown bird species appear to be improperly lumped in with other species.
In a similar study, Daniel Janzen, an evolutionary biologist at the University of Pennsylvania in Philadelphia, and colleagues sequenced mitochondrial DNA from nearly 500 specimens of the tropical skipper butterfly preserved at the Smithsonian National Museum of Natural History in Washington, D.C. DNA barcoding of the specimens reveal 10 species within the tropical skipper group, a classification that had eluded naturalists because the adult forms of the butterflies are so similar, the team reports online this week in the Proceedings of the National Academy of Sciences.
Barcoding provides a relatively rapid tool in a field in which "time is an enormous enemy," says Daniel Brooks, an evolutionary biologist at the University of Toronto in Canada. But Brooks cautions that the traditional methods are needed to confirm the designations found by barcoding.
