EPOW - Ecology Picture of the Week

Lubber With a Lesson

Lubber Grasshopper (Agriacris magnifica), Family Romaleidae
Mindo, Ecuador

Explanation:  Strikingly patterned is this lubber grasshopper!  I found this beauty in a subtropical forest outside the town of Mindo in Ecuador, along the Pacific Slope west of the peak of the Andes Mountains.  What lesson could this little fellow hold for us?

And to begin, yes, it is a little fellow.  It is a male.  And it is little.  Unlike most other grasshoppers, males of this species typically are about one-third the size of their more plainly-patterned green female mates.  So Lesson Number One is that this species exhibits sexual dimorphism (males and females appear different) in pattern, coloration, and body size.  If you didn't know better, you'd swear they're different species.

And what about the pattern on this male?  It seems to serve at least two purposes ... maybe more. First, notice how the green of its legs, sides of the wings, top of the head, and top of its pronotum all nicely match the color of the vegetation upon which it has chosen to alight.  He blends right in.  This is a nice example of camouflage.  Lesson Two.

If it was only all green, it would be like the female, and would be happy being only camouflaged to avoid its predators.  But ... it is strikingly patterned with a broad strip of green bordered by maroon eyes, sides of the pronotum, and antennae, and big spots of yellow on the side.  Why?  Because this serves as disruptive coloration that breaks up the body outline, making it much tougher to spot by its usually-visually-oriented predators such as forest birds.  Lesson Three.

So here is a remarkable example of a wonderful and uncommon combination of both camouflage and disruptive coloration rolled into one package.  Together, these add to an overall crypsis -- that is, how a creature can escape detection.  Lesson Four.

Such combination is not a particularly common occurrence in the animal world, even among other species of grasshoppers (although this lubber grasshopper we encountered in an earlier EPOW episode sports a red dorsal racing stripe that helps break up the body outline and may also serve as disruptive coloration).

How might have this combination of camouflage and disruptive coloration evolved?  What extra function might it play beyond being just green and camouflaged in its forest environment?  Well, when this gent mates, he will alight upon the back of a female; perhaps the disruptive coloration adds that extra bit of crypsis needed to hide from sharp-eyed predators so he can finish the job.

And, at that ... lesson plan over.