Some Like it Hot

It's not easy for Britain's Large Blue Butterfly to find just the right setting in which to thrive. It can't be too cold, and it can't be too hot. But by monitoring the butterflies carefully, and adjusting factors like the length of local grass, researchers have found they can protect the endangered insects.

It seems that the Large Blue Butterfly, also known as Maculinea arion, has a symbiotic relationship with a particular species of ant. But the ant is only available when the soil is at a particular temperature. Too hot or too cold, and the ants disappear. When the ants leave, the Large Blue Butterfly population declines and, finally, disappears.

Scientists discovered this process one summer when an epidemic occurred among Britain's wild rabbits. Wild rabbits nibble meadow grasses, keeping them effectively mowed to a particular height. Without the rabbits, the grasses grew — creating an extra-cool microenvironment. The sensitive ants, exposed to higher temperatures, were unable to survive. The butterflies, deprived of the ants that had once fed them, starved. Soon, the entire butterfly population had disappeared — and scientists had to reintroduce the species from populations in Scandinavia.

Now that scientists understand the complex and delicate balance between grasses, ants and butterflies, they'll be able to maintain just the right ecosystem for the large blue butterfly. By studying similar interactions among insects and their environment, they hope, they'll be able to do the same for other endangered species.

Photo Credit: Maculinea arion, by Paolo Mazzei (source: Wikipedia Commons)