New Alaskan butterfly with antifreeze in its blood tells tales about climate change

A newly identified Alaskan butterfly, which is thought to be a hybrid of two ancient species that possibly mated prior to the last ice age, could be a valuable messenger for scientists studying climate change, according to a leading lepidopterist (butterfly boffin).

But that’s not its only trick.

Butterflies are cold-blooded creatures (although they have hemolymph in  place of the claret-coloured liquid you might typically associate with blood), which means that they are unable to generate enough heat within their own bodies to stay alive, and therefore rely on the sun to warm them up.

Essentially, they’re solar powered. Which is why you see them perched on leaves with their wonderful wings spread—they’re not simply showing off, they’re catching some rays. And that’s all well and good, unless you’re a butterfly that lives in the arctic region, like the newly discovered Oeneis Tanana, which hangs out in the spruce and aspen forests of the Tanana-Yukon River Basin in Alaska. Then you have to come up with something special, such as the ability to produce your own brand of antifreeze.

Alaska has a temperature range that can lurch from 35°C in midsummer to −60°C in the depths of January, so it presents some serious challenges to all its inhabitants. Like many other animals of the extreme north, the butterfly hibernates to see out the worst of the winter. And, so its hemolymph doesn’t turn to ice whilst its asleep, the clever little creature produces a substance that works exactly the same way as antifreeze does in a car.

Unsurprisingly, Oeneis Tanana is a rather lonely species. It is thought to be the only butterfly unique to Alaska, although there are at least two other existent species of arctic butterfly. University of Florida lepidopterist Dr Andrew Warren, who was the lead author on the new paper that appeared in the Journal of Research on the Lepidoptera, has suggested that the new butterfly could actually be a hybrid of its cousins, the White-veined Arctic (Oeneis bore) and the Chryxus Arctic (Oeneis chryxus), and that it may have inherited the best features of each, enabling it to survive in such testing conditions. Such successful hybridisation is ultra rare in nature.

Butterflies are excellent indicators of climate change, and Dr Warren believes the species could help scientists studying changes in the sensitive arctic ecosystem. ‘This is a region where the permafrost is already melting and the climate is changing,’ he said.