InsectNet forum

I'm a psychology student in Turkey, recently i am working on rattus norvegicus (brown rat), we have some experiments going on right now. But we are planning to do some research about insects, for that we are planning to build an insect lab. The conditions and equipments of this lab, we got that under control. But here is the thing: Which insect species should we work on? We need an insect that's harmless and no-poisinous. We will observe their behaviors and then examine their nervous system. Right now i'm thinking about these species:

Rhagoletis pomonella, delia antiqua, tenebrio molitor. We thought about crickets but im not sure about that. Anybody help?