Bottoms Up
A Blue Dasher assuming a handstand-like position (called the obelisk posture) that some dragonflies and damselflies assume to prevent overheating on sunny days. The abdomen is raised until its tip points at the sun, minimizing the surface area exposed to solar radiation. Male Blue Dashers (Pachydiplax longipennis) assume an obelisk-like posture while guarding their territories or during conflicts with other males, displaying the blue pruinescence on their abdomens to best advantage. However, both females and males will raise their abdomens at high temperature and lower them again if shaded. This behavior can be demonstrated in the laboratory by heating captive Blue Dashers with a 250 watt lamp, and has been shown to be effective in stopping or slowing the rise in their body temperature. (Wikipedia)
Uploaded on May 18, 2009