Antlions and Vesta

November 06, 2011

Dawn

Photographer: Tommy Hornbeck; NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Summary Author: Tommy Hornbeck

NASA's Dawn spacecraft has recently arrived near the asteroid Vesta and has been taking detailed photos of Vesta's rocky surface. These photos show high plateaus, cliffs, rock strewn, valleys, and thousands of craters (see photo at right). The photo on the left, however, was taken a little closer to Earth; actually in my backyard near Nevada, Missouri. It shows half a dozen trails and traps cleverly constructed by antlions or doodle-bugs. Antlions are found worldwide, commonly in arid and sandy habitats. The adult stage is a winged creature that resembles a dragonfly -- one species has a wingspan that may reach 6 in (15 cm). The female antlion will bury her eggs in soft sand where they hatch into the larva stage -- it's larva that are responsible for the trails and craters. Any unsuspecting ant that wanders near one of the craters is trapped by the slippery slope and falls to the bottom where the antlion awaits, hidden under a bit of sand. The larva eventually make a cocoon of sand and fine silk (pupal stage), and after about a month an adult antlion will emerge, dry it's wings and be off again. We may not be likely to find life on Vesta, but my backyard is literally crawling with it. Photo on left taken on September 1, 2011.
  
Photo details: Left - Nikon D80 camera; 1.5 second exposure; f/11; ISO 100. More details about the image on the right are available here