I'm serious. My girlfriend asked me this question, and I can't stop thinking about it. 
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I'm serious. My girlfriend asked me this question, and I can't stop thinking about it. 
YES they do ! If your really serious, as they are going to the bathroom so to speak, you can sometimes hear that sound.

Tell your girlfriend I have never heard one burp though, LOL 
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Eve / PHEve
cool thanks. i'll be sure to listen for my lizards to burp too. does carbonated water help? (just kidding)
shifty is my monitor's name. he's a punk
Yes thats how mine warns me hes gonna take a dump on my shoulder.Or to let me know he just made a mess in his cage and that I better clean it up soon because it smells really bad.
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