In Litchfield National Park near Batchelor, Northern Territory, Australia, you can find two unusual species of termites. Amitermes meridionalis and Amitermes laurensis colonies build their mounds in elongated wedge-shaped forms. Usually these mounds are aligned along a magnetic north-south axis.
Why? To find out, one researcher nudged a few with his off-road vehicle. This tilted the mound out of alignment. The interior temperature of mound rose significantly.
So by building their mounds on a north-south axis, the termites increased the amount of surface area directly exposed to the sunlight as the sun travels from east to west across the sky and thus increased the rate of heat loss. Aligning their construction in this fashion keeps their mounds cooler.
-via Amusing Planet