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Name: billy
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 2000-2001

What triggers a grasshopper to become a locust?

In the movie the Exorcist, James Earl-Jones explains to Richard Burton that when there are a lot of grasshoppers together the "rubbing of the wings" between each other triggers this transformation.

Is this Accurate? If so, what exactly happens to cause this transformation in color and behavior?


Grasshoppers and locusts, assuming normal usage of the words, are different species. You might want to consult a good insect text to see the comparisons/contrasts.

Thanks for using NEWTON!

Ric Rupnik

Huh? I'm sorry, I haven't seen the movie the Exorcist, but this confirms my opinion that one should never pay much attention to any "science" in movies. Grasshoppers and locusts are completely different insects and one never becomes the other. The movie is fiction.

J. Elliott

Grasshoppers do not become locusts. However, locusts are closely related to grasshoppers in both niche and appearance. The movie is incorrect, except for one idea. Locust do not become gregarious unless there is an external stimulus. They can live independent lives, however, it has been discovered that individuals that are gregarious (groupings) can, by rubbing legs, turn independent nymphs into crowd lovers. They change color and behave with the mob!

Steve Sample

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