## Monday, August 1, 2011

### Monarch Butterfly Caterpillar

Do you know what this monarch butterfly caterpillar is doing?
 Monarch Butterfly Caterpillar
﻿   The caterpillar is sabotaging the milkweed's defense system by "bleeding" the leaf's main vein.  The caterpillar quickly notches the stem, and the milkweed's toxic, sticky latex bleeds off.  This reduces the chance of the caterpillar getting its jaws gummed up by the latex, or poisoned by too much of the milkweed's toxins.
After cutting off the flow of latex, the caterpillar turned around and began feeding on the tip of the leaf.  Of course, the caterpillar is still ingesting some of the milkweed's toxins, but those toxins are sequestered and used for the caterpillar's (and later the butterfly's) own chemical defense.

Here is another example of a monarch caterpillar sabotaging the milkweed's chemical defenses by "bleeding off" the latex.  Notice the notched stem near the main stalk.
I think a caterpillar that can deliberately hamper the chemical defenses of the milkweed and also utilize the toxins for its own protection is remarkable.  Marvelous.
That is only one of the things that is transpiring in the milkweed patch.

#### 1 comment:

1. Oh wow. That really is fascinating. My guess about what he was doing was waaay off base.