Measuring the Earth...

Have you ever seen an inchworm?  They come in all sorts of colors and sizes.  Some are incredibly cryptic—wanting you to believe that they are part of that leaf or stem or twig.  These little guys are moth larvae and belong to the family Geometridae, which means “earth measurer” (I think that name is awesome).The Geometrids are a large moth family (over 35,000 species have been described). 

An inchworm scoots along in that characteristic way because it has the six normal insect legs near the front of its body and two to three pairs of prolegs near the back of its body.  To move, it first grabs the substrate with the true legs (in the front) while pulling the back of its body forward.  Then it grabs the substrate with the prolegs (in the back) while extending the front of the body forward.  It’s pretty neat to watch.  Inchworms also have a survival strategy of standing erect and very very still when disturbed—it works because they can easily be mistaken for a twig or piece of leaf.

Despite the cuteness of the little inchworms, the adult Geometer moths are sort of boring and ugly although some do have an intricate wavy pattern across the four pairs of wings.   Like many moths that fly at night, they have tympanal organs that help them hear (and hopefully avoid) ecolocating bats that are trying to eat them.

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"Teaching a child not to step on a caterpillar is as valuable to the child as it is to the caterpillar."

-Bradley Millar