For insects in Europe, climate change has led to habitat change. In the past couple of decades, for example, Mediterranean butterfly and dragonfly species have been found flying around places previously off limits to them—new new northern climes such as Germany.
Now a study in Nature Communications finds a colorful reason for the northern expansion. As northern Europe warms, the light-colored butterflies and dragonflies typically found in the Mediterranean find themselves able to survive in the newly warmer north, and to even outcompete their darker-colored rivals. [Dirk Zeuss et al, Global warming favours light-coloured insects in Europe]
Lighter colors reflect sunlight while dark colors absorb it and heat up. Hence chocolate ice cream melts in the sun faster than vanilla. Lighter-colored insects thus function well in warmer climates. They don’t overheat as easily and can stay active longer, giving them a leg up—well, six legs up—in our warming world.
The researchers say this migration of insects shows that climate change isn’t something that’s coming—it’s already happening. And it could drastically affect which insects up end up where. Which will in turn affect us.
[The above text is a transcript of this podcast.]
[Scientific American is part of Nature Publishing Group.]