Here's why:
* Vulnerability: Their bellies are exposed and vulnerable, so they feel less secure when someone touches them there.
* Grooming: Guinea pigs groom themselves and each other, so touching their bellies can feel strange and potentially invasive to them.
* Individual preferences: Some guinea pigs might be more tolerant of belly rubs than others.
Instead of trying to rub their bellies, focus on:
* Back scratches: This is usually a safe and enjoyable experience for guinea pigs.
* Chin scratches: Many guinea pigs love to have their chins scratched.
* Gentle head strokes: This can help them relax and feel safe.
Always be gentle and respectful when interacting with your guinea pig. If they seem uncomfortable or tense, stop what you're doing and give them space.