I own a chameleon so I constantly have a store of live crickets to feed her. Those crickets sometimes manage to escape so I wanted a passive way to catch them. The idea is that some sort of bait is placed in the middle to lure the crickets to fall into the trap. Once inside the steep walls prevent the cricket from jumping out. I never had a chance to test this so it may or may not actually work.
The author hasn't provided the model origin yet.